In this experiment carried out on Caribbean chili pepper plants(Capsicum chinensis),the bio-insecticide azadirachtin in combination with an NPK fertilizer proved to have a greater lethal impact on the larvae of Aedes ...In this experiment carried out on Caribbean chili pepper plants(Capsicum chinensis),the bio-insecticide azadirachtin in combination with an NPK fertilizer proved to have a greater lethal impact on the larvae of Aedes albopictus than each substance on its own.This synergistic effect is noticeably important when both inputs are sprayed directly on the leaves of the plant(foliar application).While the plants treated with azadirachtin or NPK alone cause a 33.6%and 36.4%mortal-ity respectively of the Ae.albopictus larvae,the combination of the two inputs induces a 74.4%mortality on the mosquito larvae.To account for this synergistic effect phenomenon inside the plant,the azadirachtin+NPK combination most likely interacts with the capsaicinoid compounds naturally produced by the plant.Not only does this study carried out on azadirachtin reveal major results but the methodology itself offers a most interesting approach on how to boost the agricultural inputs within the plants.As a matter of fact,this research axis demands developing since the control of pests harmful to men has been dramatically lacking insecticide molecules acting on new targets over the past three decades.展开更多
The cultivation of fruit trees generally requires a nursery phase during which the young seedlings are monitored and treated to improve their ability to adapt to the environment. This leads to the production of seedli...The cultivation of fruit trees generally requires a nursery phase during which the young seedlings are monitored and treated to improve their ability to adapt to the environment. This leads to the production of seedlings that are used to create orchards. It consists of four essential steps or operations: 1) The germination phase of the seeds in germinators for the production of rootstocks;2) Transplanting into pots or bags;3) Fertilisation in order to obtain seedlings of a satisfactory vigour (stem diameter) ready for grafting. The nursery phase requires a good understanding and mastery of plant regeneration and fertilisation techniques. In Cameroon, the demand for avocado (Persea americana) fruits is increasing, but the supply is not keeping up with this demand. After a summary monograph on the production practices of avocado seedlings in the Yaounde area, this work aims to optimise the aforementioned three steps in order to obtain seedlings of sufficient sizes for grafting. Three factors are considered in this study: 1) The substrate (Substrate), whose effects are evaluated by the germination rate (GR), the daily average germination (DAG) and the root volume of seedlings (RootV). 2) The transplanting date (TransD), determined by considering three dates including 40 (Trans40), 65 (Trans65) and 75 (Trans75) days after sowing, and 3) Fertilisation using biological fertilisers, evaluated by testing four fertilisation levels, Fert1 (10 gr of 20-10-10 plus 10 gr fowl droppings), Fert2 (Acaulospora tuberculata), Fert3 (Gigaspora margarita) and Fert4 (Mixed mycorrhizal strains of Gigaspora margarita and Acaulospora tuberculata). This third factor is evaluated by growth parameters including leaf area (LeafA), chlorophyll index (ChlorInd), gain in Plant height (GainPltH) and plant diameter (GainPltD). The trial took place in the First Seed company, a seed production unit located in the Simbock district of Yaounde for the field phase, and the Biological Control Laboratory of the Institute of Agricultural Research for Development (IRAD), Nlolbisson, Yaounde. Two trials were conducted, the first with the objective of determining the best substrate with a completely randomized block design in 2 replications, three substrates/replication. The second trial was done with a factorial design (Split plot) with three replicates, the main factor being the Transplanting Date (TransD) and the second factor the biological fertilizer. Data were separated using least significant difference at 5% treshhold. Results indicate a highly significant effect of substrate on RootV (p = 5.00E-03). This effect translated by an increase of 49.42% and 19.53% of root volume on sawdust respectively to sand and soil. Sawdust (100%) and soil (98%) affect germination by 8 days reduction over sand and the germination rate on these two substrates is higher than the one on sand (92%). The early transplanting (TransD40) allows a better growth of the seedlings in terms of stem length and the collar diameter. The only observation variable that stands out for the early nursery stage fertilisation is leaf area, which shows significant differences between the 4 fertilisation formulae tested. The chlorophyll index and leaf area are also strongly correlated with the seedling growth parameters. Our results show that the early transplanting stage (40 days after planting) combined with a germination on white sawdust should be proposed to reduce the production cycle of grafted seedlings in association with early application of biofertilisers or organic fertilizer.展开更多
This study, which took place around the Boumba-Bek National Park (BBNP) in Cameroon, was based on identifying and characterizing stakeholders in forest resources management, as well as determining the relationships be...This study, which took place around the Boumba-Bek National Park (BBNP) in Cameroon, was based on identifying and characterizing stakeholders in forest resources management, as well as determining the relationships between them, with the goal of encouraging collaborative forest resources management. Purposive sampling was adopted, in which focus group discussions, key informant interviews, semi-structured interviews, and snowball sampling were used for data collection. Focus group discussions were conducted with a total of 20 local associations involved in forest and wildlife management, Bantu traditional councils and the Baka community. Key informant interviews were conducted with local and international NGOs, forest exploitation and Sport hunting (Safari) enterprises and local public administrations that had working rapports with village communities around the BBNP. Information was generally sought on the role of stakeholders in forest management, in terms of use, protection, policy enforcement, challenges encountered in their activities and their relationships with other stakeholders. Actor linkage matrix was used to establish the relationships between different stakeholders. The identified stakeholder groups included the local community, State, international and local NGOs, economic operators (forest exploitation and sport hunting enterprises), and also the rules guiding their activities. Conflicts were rife between the community and the other stakeholders with regard to resource accessibility and use, whereas intra-community conflicts mostly resulted from cases of corruption and embezzlement linked to benefits sharing. Cases of collaboration among all the stakeholders were mostly related to anti-poaching patrols and setting of forest concession limits. There is a need to bring all stakeholders on the same platform, such as in a consultation workshop, to get their perceptions on building trust, conflict resolution and genuine collaboration in resources management.展开更多
Plant biofertilization involves introducing compounds containing living mi-croorganisms into the coating medium to sustainably enhance plant production and soil health. This is a complex process that undergoes multipl...Plant biofertilization involves introducing compounds containing living mi-croorganisms into the coating medium to sustainably enhance plant production and soil health. This is a complex process that undergoes multiple stages of development before yielding a final product. The final biofertilizer is used by legumes-protein-rich crops in symbiosis with rhizobia to enable biological nitrogen fixation increasing natural soil fertility. This study aims to determine the optimal formulation of a rhizobial biofertilizer to improve the performance of soybean (Glycine max L. cv. Docko). To this end, soybean seeds obtained from IRAD were coated with different formulations derived from locally sourced materials. Palm kernel oil was used as an adhesive in one group, while corn powder served as an adhesive in another. The coated seeds were then sown in the field. The results indicate that the combination of pigeon pea powder + sugarcane molasses, with palm kernel oil as an adhesive, produced the best nodulation (nitrogen fixation). This formulation also led to significant improvements in growth (+350%) and total nitrogen content (+1100%) compared to the bacterial broth inoculum control (B0) (P ≤ 0.01). These findings represent a significant advancement in improving nitrogen-fixing bacterial inoculants and enhancing soil fertility for the sustainable cultivation of soybeans in this tropical soil.展开更多
A 4 MeV RF linear accelerator for electron beam irradiation applications has been developed at the PBP-CMU Electron Linac Laboratory,Thailand.The system has been reengineered using a decommissioned medical linear acce...A 4 MeV RF linear accelerator for electron beam irradiation applications has been developed at the PBP-CMU Electron Linac Laboratory,Thailand.The system has been reengineered using a decommissioned medical linear accelerator.The main components include a thermionic DC electron gun,an RF linear accelerator,a beam diagnostic chamber,and a beam exit window for electron beam irradiation.Therefore,reengineering must be performed based on the characteristics of the electron beam and its dynamics throughout the system.In this study,the electron beam current density emitted from the cathode was calculated based on the thermionic emission theory,and the result was used to produce the electron beam distribution in the gun using CST Studio Suite^(■)software.The properties of the electron beam and its acceleration in the linear accelerator and downstream diagnostic section were studied using the ASTRA electron beam dynamics simulation code,with the aim of producing an electron beam with an average energy of 4 MeV at the linear accelerator exit.The transverse beam profile and electron deposition dose in the ambient environment were calculated using Geant4 Monte Carlo simulation software to estimate the beam performance for the irradiation experiments.The parameters studied can be used as guidelines for machine operation and future experimental plans.展开更多
Chronic obstructive pulmonary disease(COPD)is a respiratory condition characterized by several symptoms.The pathogenesis of COPD is complex and involves multiple factors.A fantastic drug from traditional Chinese medic...Chronic obstructive pulmonary disease(COPD)is a respiratory condition characterized by several symptoms.The pathogenesis of COPD is complex and involves multiple factors.A fantastic drug from traditional Chinese medicine,Isodon Suzhouensis(ISZ)is a perennial herb belonging to the Labiaceae family.It has the functions of resolving phlegm,removing stasis,promoting blood circulation and eliminating qi stagnation.ISZ has been found to possess great potential against COPD.Present study is focused on identifying micro RNA(mi RNA)biomarkers for COPD and determining the role of ISZ leaf extract in regulating the disease through mi RNA expression in serum exosomes.The Sprague Dawley(SD)rats were randomly divided into control group,COPD group and COPD+ISZ group.After the establishment of the model,the rats were sacrificed,and the results were compared with the control group.Then the total RNA of rat serum was extracted and identified by nanoparticle tracker.Finally,high-throughput screening and sequencing were performed to screen mi RNAs with significant differential expression.Then,different databases were used to figure out the possible target genes,and their functions were assessed by employing Gene Ontology(GO)as well as Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses.The sequencing results were then further verified by q RT-PCR.The results pointed out that these 17 differentially expressed mi RNAs may have the potential of diagnostic and prognostic biomarkers against COPD.Interestingly,it was also found that ISZ leaf extract may regulate the occurrence of COPD by affecting the expression of mi RNAs.This study identified the biomarkers of COPD and clarified the mechanism of the treatment of COPD by ISZ leaf extract,which is helpful to improve the level of early diagnosis and treatment of COPD.展开更多
Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has...Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has focused on developing or improving THz sources,detectors,and applications.At the PBP-CMU Electron Linac Laboratory(PCELL)of the Plasma and Beam Physics Research Facility in Chiang Mai University,high-intensity THz radiation has been generated in the form of coherent transition radiation(TR)and investigated since 2006 for electron beams with energies ranging from 8 to 12 MeV.In this study,we investigate and optimize the coherent TR arising from short electron bunches with energies ranging from 8 to 22 MeV using an upgraded linear-accelerator system with a higher radio-frequency(RF)power system.This radiation is then transported from the accelerator hall to the experimental room,in which the spectrometers are located.Electron-beam simulations are conducted to achieve short bunch lengths and small transverse beam sizes at the TR station.Radiation properties,including the radiation spectrum,angular distribution,and radiation polarization,are thoroughly investigated.The electron-bunch length is evaluated using the measuring system.The radiation-transport line is designed to achieve optimal frequency response and high transmission efficiency.A radiation-transmission efficiency of approximately 80-90%can be achieved with this designed system,along with a pulse energy ranging from 0.17 to 0.25μJ.The expected radiation spectral range covers up to 2 THz with a peak power of 0.5-1.25 MW.This coherent,broadband,and intense THz radiation will serve as a light source for THz spectroscopy and THz time-domain spectroscopy applications at the PCELL in the near future.展开更多
In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to g...In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction（GGE） biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley（YaRV）, China. Four traits（cotton lint yield, fiber length, lint breaking tenacity, micronaire） and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments： a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none.展开更多
Highly weathered soils are distributed in the humid and wet-dry tropics, as well as in the humid subtropics. As a result of strong weathering, these soils are characterized by low activity clays, which develop variabl...Highly weathered soils are distributed in the humid and wet-dry tropics, as well as in the humid subtropics. As a result of strong weathering, these soils are characterized by low activity clays, which develop variable surface charge and related specific properties. Surface reactions regarding base exchange and soil acidification, heavy metal sorption and mobility, and phosphorus sorption and availability of the tropical highly weathered soils are reviewed in this paper.Factors controlling surface reactivity towards cations and anions, including ion exchange and specific adsorption processes, are discussed with consideration on practical implications for rational management of these soils. Organic matter content and pH value are major basic factors that should be controlled through appropriate agricultural practices, in order to optimise favorable effects of colloid surface properties on soil fertility and environmental quality.展开更多
Severalα-glucosidase inhibitory constituents were isolated from the methanolic extract of the leaves of Quercus phillyraeoides A.Gray(Q.phillyraeoides)using a bioassay-guided fractionation technique.Further separatio...Severalα-glucosidase inhibitory constituents were isolated from the methanolic extract of the leaves of Quercus phillyraeoides A.Gray(Q.phillyraeoides)using a bioassay-guided fractionation technique.Further separation and purification of the methanol-soluble fraction led to the isolation of constituents with moderate and strong inhibitory activities againstα-glucosidase:α-sitosterol-d-glucoside(1)and condensed tannin fractions(2,3,4,5,and 6).Compound 1 and fractions 2-6 had inhibitory concentration(IC50)values againstm-glucosidase from Saccharomyces cerevisiae of 118.8,2.79,2.78,3.10,2.60,and 3.14μg/mL,respectively,while quercetin as the standard had an IC50 value of 4.80mg/mL.Furthermore,the significant antioxidant activities were evaluated using several assays,such as the DPPH radical scavenging,hydrogen peroxide radical scavenging,reducing power,andβ-carotene-linoleate bleaching assays,and the results suggested that the isolated constituents showed their possible application for treating the hyperglycemia-induced oxidative stress.The results of the present study showed the potential of Q.phillyraeoides as a rich source of natural antidiabetic medicine.展开更多
This study of the impact of heart rot of <i><span style="font-family:Verdana;">Pericopsis elata</span></i><span style="font-family:Verdana;"> on logging yield was cond...This study of the impact of heart rot of <i><span style="font-family:Verdana;">Pericopsis elata</span></i><span style="font-family:Verdana;"> on logging yield was conducted in Libongo, in three logging concessions of the </span><i><span style="font-family:Verdana;">Société d'Exploitation Forestière et Agricole du Cameroun</span></i><span style="font-family:Verdana;"> (SEFAC). An inventory of 92 </span><i><span style="font-family:Verdana;">P. elata</span></i><span style="font-family:Verdana;"> stumps in four Annual Cutting Areas (AACs) divided among three Forest Management Units (FMUs) distinguished by Minimum Operating Diameter </span><span style="font-family:Verdana;">(MOD) revealed that 22 stumps were rotten. Decay was visible on stumps wit</span><span style="font-family:Verdana;">h a diameter of more than 100 cm with a frequency of occurrence of 23.91%, a percentage of abandonment of 55.20% and a yield of 44.79%. The most important economic loss was revealed on 9 abandoned whole logs that cumu</span><span><span style="font-family:Verdana;">lated a volume of 145.547 m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">. The correlation between the diameter of the</span></span><span style="font-family:Verdana;"> stumps and that of the decay gives a coefficient or correlation rate r = 0.31. The MOD for </span><i><span style="font-family:Verdana;">P. elata</span></i><span style="font-family:Verdana;"> could be 80 cm and covers the biological risk class. The results indicate that </span><i><span style="font-family:Verdana;">P. elata</span></i><span style="font-family:Verdana;"> shows an increasing gradient of decay rate with increasing tree diameter, resulting in a loss of material for larger diameter trees, and consequently a decrease in material yield at processing.</span>展开更多
This study was carried out in the forest reserve of Mbalmayo, Center Region of Cameroon, with the aim to analyze the dynamics of land use/land cover (LULC) changes over the past 30 years. The databases used were made ...This study was carried out in the forest reserve of Mbalmayo, Center Region of Cameroon, with the aim to analyze the dynamics of land use/land cover (LULC) changes over the past 30 years. The databases used were made up of 3 Landsat satellite images (5TM of 1990, 7ETM+ of 2005 and 8OLI of 2020). The satellite images were processed using ArcGIS and Erdas Imagine software. Ethnobotanical surveys were conducted to investigate the relationships between the local population and the forest reserve. The Mbalmayo forest reserve is consisted of seven main land cover namely: mature secondary forest, young secondary forest, savanna, fallows and crops, built, bare soil and water surface. The dynamics of the forest cover undergoes more significant changes between the years 1990-2005 with losses estimate at 4762 ha compared to the years 2005-2020 (2231 ha), with a marked decrease in the area of dense forests. This regression is much more important in dense forest vegetation. The forest cover lost 6993 ha (26.92%) of its surface, which corresponds to an average rate of deforestation of 233.1 ha/year. The survey revealed the need for NTFPs for the Mbalmayo reserve forest populations. Indeed, all respondents agreed that they use non-timber forest products from the forest, mainly for medication (37%), wood (34%) and food (24%). Therefore, it becomes urgent to redefine a management plan for the Mbalmayo forest reserve which will define how the forest must be managed in order to avoid the loss of large areas of forests disappearing each year under the human action, which exerts pressure on forest species, thus leading to their possible disappearance.展开更多
Sorghum bicolor is among main staple crops of Chad but it is commonly attacked by Striga hermonthica. Assessment of sorghum varieties for resistance to this weed was carried out during three cropping seasons （2005-2...Sorghum bicolor is among main staple crops of Chad but it is commonly attacked by Striga hermonthica. Assessment of sorghum varieties for resistance to this weed was carried out during three cropping seasons （2005-2008）, in controlled conditions; promising entries （those which fulfilled at least 75% of selection criteria） were evaluated in farmer field in 2008-2009 seasons. There were five sites （Bebedjia, Deli, Bekao, Koudoti and Ndaba）. The objective was to evaluate some sorghum entries for S. hermonthica resistance in farmer field. Sorghum test was composed of four entries in Fisher blocks as experimental designs, with five replications. Among different observed variables, there were striga plant count and weight of sorghum grains. One promising entry was selected at Bebedjia and Ndaba （53）, two at Deli and Koudoti （50 and 53）. No entry was selected at Bekao. Promising entries for the whole Southern zone of Chad were composed of 50 and 53. The best entry was 53 because it was promising in all sites except Bekao.展开更多
An investigation to assess the spatial structure and severity of Pseudocercospora leaf and fruit spot disease (PLFSD) on citrus trees in cocoa-based agroforests was carried out in three contrasting ecological zones in...An investigation to assess the spatial structure and severity of Pseudocercospora leaf and fruit spot disease (PLFSD) on citrus trees in cocoa-based agroforests was carried out in three contrasting ecological zones in southern Cameroon, viz: 1) the humid forest zone, 2) the degraded forest zone, and 3) the forest-savannah transition zone. Two main parameters were investigated viz: 1) the spatial structure of cocoa based agroforests, and 2) the disease severity. In total, the spatial structure of 19 cocoa-based agroforests was analysed using the Ripley K(r) function, meanwhile the collection of epidemiological data that consisted of noting the presence of PLFSD spots on leaves and fruits on 438 citrus trees was used to characterise the severity of the disease. Results showed that, the spatial structure of citrus trees in these agroforests investigated were regular in seven plots, random in nine, and aggregated in three. Aggregated plots presented a significantly higher mean of disease severity on leaves and fruits (28.55 and 30.37 respectively), as compared to randomised (20.91 and 16.32 respectively) and regular plots (16.28 and 14.97 respectively), at P-value < 0.05. These results suggest that the spatial structure of citrus trees in the cocoa-based agroforests studied influences the severity of PFLSD. Proper integrated control measures can therefore be initiated, leading to a considerable reduction of the use of manufactured inputs, and thereby, the cost of production of citrus fruits.展开更多
This study emphasizes the formulation of three types of cookies viz potato flour with date powder and bean milk (PDBM), potato flour with sugar and bean milk (PSBM), and potato flour, sugar, and eggs as control. After...This study emphasizes the formulation of three types of cookies viz potato flour with date powder and bean milk (PDBM), potato flour with sugar and bean milk (PSBM), and potato flour, sugar, and eggs as control. After the substitution, the highest protein content was observed in PDBM (1.78 ± 0.12)% followed by PSBM, (1.35 ± 0.01)% and the lowest was in the control (0.91 ± 0.55)%. Moreover, cookies fortified with date palm powder increased the carbohydrate and fat contents compared to the control and significantly increased the calorific value of PDBM. The formulated cookies were significantly higher (p < 0.05) in iron (39.95 ± 3.00) mg/100 g and zinc (13.65 ± 1.61) mg/100 g in PDBM compared to other cookies. The date palm powder incorporated in cookies significantly increases the darkening of biscuits during cooking. The organoleptic characteristics of PDBM and PSBM were rated overall best when specific parameters were tested. With the shortage of wheat and importation constraints, an alternative provides a great market opportunity for local products like potatoes and beans. In addition, fortifying food products as cookies eaten by all will contribute to a more food and nutrition-secured world.展开更多
The purpose of the study was to establish the structure of monitored animal farms and determine reproductive parameters of Sahelian goats in the Guera Region, in Central Chad. Data were collected through longitudinal ...The purpose of the study was to establish the structure of monitored animal farms and determine reproductive parameters of Sahelian goats in the Guera Region, in Central Chad. Data were collected through longitudinal survey in 27 observatory farms during three years using goats identified by numbered ear tags. The herds were composed on average of about 71% of females. The age pyramid covering all years showed a significant number of males aged between 0 - 1 year and perceptible fall thereafter. However, some stability was observed in the class of the 2 - 8 years old among females. The frequencies of accumulated kiddings showed that 44% of births occurred in the rainy season against 28% respectively in the cool dry and hot dry seasons. Obtained reproduction parameters were: a sex ratio of 0.51 in favor of males, a kidding interval of 10.6 months with significant differences (P < 0.05) according to the rank of birth, an age at first kidding of 16.5 months for females born in monitoring and an age of 20.3 months for all first-kidding, giving an apparent fertility rate of 145%, a fecundity rate of 116% and an abortion rate of 2%. The composition and structure of herds have highlighted the importance of females to ensure the reproducibility of goat production systems. The determined reproduction parameters are references for actions to improve goat rearing in this area.展开更多
<span style="font-family:Verdana;">In order to contribute to the improvement of the knowledge on the</span><span><span><span style="font-family:;" "="">...<span style="font-family:Verdana;">In order to contribute to the improvement of the knowledge on the</span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> valorization of biochar as a feed additive in livestock, three biochar made from cassava peelings, bean tops and cocoa pods were manufactured. After analyzing their mineral composition, they were incorporated into rations at a rate of 0.8% in order to evaluate their effects on the performance of reproduction and pre-weaning growth in cavy (</span><i><i><span style="font-family:Verdana;">Cavia</span></i><span> <i><span style="font-family:Verdana;">porcellus</span></i><span style="font-family:Verdana;"></span></span></i></span></span><span style="font-family:Verdana;">). The trials were conducted in the Research Unit of Animal Production and Nutrition (URPRONAN) of the University of Dschang, on 96 adult local breed cavy (from the first generation), including 80 females and 16 males aged 4 months and with an average weight of 400 ± 0.25 g. After 2 weeks of adaptation in the rearing boxes at the farm, the females were put in reproduction for a period of 31 days, the animals were divided into 04 batches of 20 females and 4 males. The animals in the control lot were fed a compound feed without biochar (T) while the oth</span><span style="font-family:Verdana;">ers were fed the compound feed containing 0.8% of cassava peel biochar</span><span style="font-family:Verdana;"> (EM), 0.8% of bean tops biochar (FH) and 0.8% of cocoa pod husks biochar (CC) respectively. The results of this study showed that the ash content (26%) and macro-element concentration were higher in the bean husk charcoal compared to the other charcoals and the trace elements were more concentrated in the cassava peel charcoal. The best fertility rate (87.5%) was obtained in </span><span style="font-family:Verdana;">animals receiving the ration containing organic cocoa pod charcoal. The</span><span style="font-family:Verdana;"> highest abortion rate (63.16%) was obtained in the batch of animals receiving the </span><span style="font-family:Verdana;">ration containing organic bean husk charcoal. Pre-weaning mortality rates </span><span style="font-family:Verdana;">were comparable between the different rations. Piglet weights at birth were comparable between the different rations. At weaning, the highest average weight of the kids was recorded with the ration containing the organic bean charcoal (197.25 ± 46.9 g). The highest ADG (4.82 ± 0.74 g/d) and TG (101.25 g) were recorded in the batch of animals receiving the FH ration. Thus, the incorporation of 0.8% of the powder of organic coals seems to have adverse effects on reproductive performance. On the other hand, these coals significantly improve the pre-weaning growth performance in cavy.</span></span>展开更多
Trypanosomosis remains the number one killer of livestock in spite of efforts made to eradicate tsetse flies in the Adamawa plateau of Cameroon. Acetone-baited Laveissière type biconical traps were pitched at 100...Trypanosomosis remains the number one killer of livestock in spite of efforts made to eradicate tsetse flies in the Adamawa plateau of Cameroon. Acetone-baited Laveissière type biconical traps were pitched at 100 meter intervals in strategic geo-referenced positions in various ecological niches of the landscape for 5 consecutive days in selected villages in Mayo Rey, Mbere, Vina and Faro et Deo divisions. All 493 tsetse flies captured in sites other than Mboula wereG. morsitans submositans.Measurement of different morphometric characters on the wings of each individual fly was undertaken using the Du Jardin package. The data was processed and analysed by “Permutaciones, Analisis Discriminante (PAD)” and “Bootstraps, Analisis en Componentes principales”. The three major sampling sites on the plateau yielded similar results as demonstrated by the neighbour joining tree of Mahalanobis distances but tests using PAD showed the differences between group means to be significant展开更多
The effects of climate change have had a major impact on forage availability in the Sahel and Saharan regions of Chad in recent years. This has led to the migration of farmers in search of long-distance grazing, thus ...The effects of climate change have had a major impact on forage availability in the Sahel and Saharan regions of Chad in recent years. This has led to the migration of farmers in search of long-distance grazing, thus impacting the potential of the animals to produce good quality milk and meat. It is with this in mind that this study was conducted on the knowledge of feeding practices of animals in the provinces of Wadi-Fira and West-Ennedi (Chad) during the lean period. More specifically, it is a question of collecting some information on the plants consumed by the animals and the way in which the breeders formulate the food ration of their herds in times of deficit. It emerges from this investigation that the herds of animals in the province of Wadi-Fira faced with forage deficit and adapted by consuming the leaves, fruits and seeds of certain tropical plants such as Capparis decidua, Ziziphus mauritiana, Balanites aegyptiaca, Acacia tortilis, Boscia senegalensis, Salvadora percica and Tribulis terristris to compensate for food shortages. This same observation was made in the province of West-Ennedi, since this area is desert with annual precipitation of 150 mm. Natural pasture is only available around water points (ouadis and oasis) in a small area with a high number of herds. Thus, the herds also face a drastic lack of grazing during the deficit periods. However, they adapt by consuming the leaves, fruits and seeds of plants such as Bauhinia sp., Boscia senegalenis, Acacia tortilis, Tribulis terristris, Boscia angustifolia, Bicoma tomentosa, Blepharis linarifolia and Aristida funiculata during lean periods to meet their food requirements. The formulation of the feed ration for animals differs from one area to another. It is mainly based on residues from cereals such as millet (Panicum miliaceum) and sorghum (Sorghum bicolor).展开更多
The Sudanian-Sahelian zone of the Far-North Cameroon faces an extreme climate challenge resulting in increased vulnerability to erosion, soil degradation, and the effects of climate change, impacting soil fertility an...The Sudanian-Sahelian zone of the Far-North Cameroon faces an extreme climate challenge resulting in increased vulnerability to erosion, soil degradation, and the effects of climate change, impacting soil fertility and agricultural yields. The objective of this study was to analyze agricultural practices, challenges related to climate change and soil degradation, as well as the solutions adopted by farmers to address these issues. To achieve this, 600 farmers from the six departments of the region were interviewed. The results highlight the significant impact of climatic conditions on soil health, agricultural activities, and food security. Farmers identified various indicators of soil degradation, including agricultural yields, bioindicator plants, plant growth, soil fauna, and root density. The main causes of soil degradation are associated with practices such as deforestation, intensive agriculture, the use of chemical fertilizers and pesticides, overgrazing, and the effects of climate change. The impacts of this degradation are multiple, including soil fertility loss, reduced agricultural yields, deforestation, reduced biodiversity, income loss, water resource pollution, and food insecurity. In response to these challenges, farmers have adopted sustainable soil management practices, including crop rotation, intercropping, fallowing, the use of organic fertilizers, and the adoption of conservation agriculture. To effectively address these challenges, concerted collaboration between farmers, civil society organizations, and government authorities is imperative to develop sustainable and effective solutions against soil degradation in the region.展开更多
文摘In this experiment carried out on Caribbean chili pepper plants(Capsicum chinensis),the bio-insecticide azadirachtin in combination with an NPK fertilizer proved to have a greater lethal impact on the larvae of Aedes albopictus than each substance on its own.This synergistic effect is noticeably important when both inputs are sprayed directly on the leaves of the plant(foliar application).While the plants treated with azadirachtin or NPK alone cause a 33.6%and 36.4%mortal-ity respectively of the Ae.albopictus larvae,the combination of the two inputs induces a 74.4%mortality on the mosquito larvae.To account for this synergistic effect phenomenon inside the plant,the azadirachtin+NPK combination most likely interacts with the capsaicinoid compounds naturally produced by the plant.Not only does this study carried out on azadirachtin reveal major results but the methodology itself offers a most interesting approach on how to boost the agricultural inputs within the plants.As a matter of fact,this research axis demands developing since the control of pests harmful to men has been dramatically lacking insecticide molecules acting on new targets over the past three decades.
文摘The cultivation of fruit trees generally requires a nursery phase during which the young seedlings are monitored and treated to improve their ability to adapt to the environment. This leads to the production of seedlings that are used to create orchards. It consists of four essential steps or operations: 1) The germination phase of the seeds in germinators for the production of rootstocks;2) Transplanting into pots or bags;3) Fertilisation in order to obtain seedlings of a satisfactory vigour (stem diameter) ready for grafting. The nursery phase requires a good understanding and mastery of plant regeneration and fertilisation techniques. In Cameroon, the demand for avocado (Persea americana) fruits is increasing, but the supply is not keeping up with this demand. After a summary monograph on the production practices of avocado seedlings in the Yaounde area, this work aims to optimise the aforementioned three steps in order to obtain seedlings of sufficient sizes for grafting. Three factors are considered in this study: 1) The substrate (Substrate), whose effects are evaluated by the germination rate (GR), the daily average germination (DAG) and the root volume of seedlings (RootV). 2) The transplanting date (TransD), determined by considering three dates including 40 (Trans40), 65 (Trans65) and 75 (Trans75) days after sowing, and 3) Fertilisation using biological fertilisers, evaluated by testing four fertilisation levels, Fert1 (10 gr of 20-10-10 plus 10 gr fowl droppings), Fert2 (Acaulospora tuberculata), Fert3 (Gigaspora margarita) and Fert4 (Mixed mycorrhizal strains of Gigaspora margarita and Acaulospora tuberculata). This third factor is evaluated by growth parameters including leaf area (LeafA), chlorophyll index (ChlorInd), gain in Plant height (GainPltH) and plant diameter (GainPltD). The trial took place in the First Seed company, a seed production unit located in the Simbock district of Yaounde for the field phase, and the Biological Control Laboratory of the Institute of Agricultural Research for Development (IRAD), Nlolbisson, Yaounde. Two trials were conducted, the first with the objective of determining the best substrate with a completely randomized block design in 2 replications, three substrates/replication. The second trial was done with a factorial design (Split plot) with three replicates, the main factor being the Transplanting Date (TransD) and the second factor the biological fertilizer. Data were separated using least significant difference at 5% treshhold. Results indicate a highly significant effect of substrate on RootV (p = 5.00E-03). This effect translated by an increase of 49.42% and 19.53% of root volume on sawdust respectively to sand and soil. Sawdust (100%) and soil (98%) affect germination by 8 days reduction over sand and the germination rate on these two substrates is higher than the one on sand (92%). The early transplanting (TransD40) allows a better growth of the seedlings in terms of stem length and the collar diameter. The only observation variable that stands out for the early nursery stage fertilisation is leaf area, which shows significant differences between the 4 fertilisation formulae tested. The chlorophyll index and leaf area are also strongly correlated with the seedling growth parameters. Our results show that the early transplanting stage (40 days after planting) combined with a germination on white sawdust should be proposed to reduce the production cycle of grafted seedlings in association with early application of biofertilisers or organic fertilizer.
文摘This study, which took place around the Boumba-Bek National Park (BBNP) in Cameroon, was based on identifying and characterizing stakeholders in forest resources management, as well as determining the relationships between them, with the goal of encouraging collaborative forest resources management. Purposive sampling was adopted, in which focus group discussions, key informant interviews, semi-structured interviews, and snowball sampling were used for data collection. Focus group discussions were conducted with a total of 20 local associations involved in forest and wildlife management, Bantu traditional councils and the Baka community. Key informant interviews were conducted with local and international NGOs, forest exploitation and Sport hunting (Safari) enterprises and local public administrations that had working rapports with village communities around the BBNP. Information was generally sought on the role of stakeholders in forest management, in terms of use, protection, policy enforcement, challenges encountered in their activities and their relationships with other stakeholders. Actor linkage matrix was used to establish the relationships between different stakeholders. The identified stakeholder groups included the local community, State, international and local NGOs, economic operators (forest exploitation and sport hunting enterprises), and also the rules guiding their activities. Conflicts were rife between the community and the other stakeholders with regard to resource accessibility and use, whereas intra-community conflicts mostly resulted from cases of corruption and embezzlement linked to benefits sharing. Cases of collaboration among all the stakeholders were mostly related to anti-poaching patrols and setting of forest concession limits. There is a need to bring all stakeholders on the same platform, such as in a consultation workshop, to get their perceptions on building trust, conflict resolution and genuine collaboration in resources management.
文摘Plant biofertilization involves introducing compounds containing living mi-croorganisms into the coating medium to sustainably enhance plant production and soil health. This is a complex process that undergoes multiple stages of development before yielding a final product. The final biofertilizer is used by legumes-protein-rich crops in symbiosis with rhizobia to enable biological nitrogen fixation increasing natural soil fertility. This study aims to determine the optimal formulation of a rhizobial biofertilizer to improve the performance of soybean (Glycine max L. cv. Docko). To this end, soybean seeds obtained from IRAD were coated with different formulations derived from locally sourced materials. Palm kernel oil was used as an adhesive in one group, while corn powder served as an adhesive in another. The coated seeds were then sown in the field. The results indicate that the combination of pigeon pea powder + sugarcane molasses, with palm kernel oil as an adhesive, produced the best nodulation (nitrogen fixation). This formulation also led to significant improvements in growth (+350%) and total nitrogen content (+1100%) compared to the bacterial broth inoculum control (B0) (P ≤ 0.01). These findings represent a significant advancement in improving nitrogen-fixing bacterial inoculants and enhancing soil fertility for the sustainable cultivation of soybeans in this tropical soil.
基金supported by Chiang Mai University for providing infrastructure and the NSRF via the Program Management Unit for Human Resources&Institutional Development,Research and Innovation[grant number B05F650022]for the software CST Studio Suite^(■)2023Financial support for the reengineering and commissioning of the accelerator system was provided by the Thailand Center of Excellence in Physics(ThEP Center),Science and Technology Park Chiang Mai University(CMU STeP)。
文摘A 4 MeV RF linear accelerator for electron beam irradiation applications has been developed at the PBP-CMU Electron Linac Laboratory,Thailand.The system has been reengineered using a decommissioned medical linear accelerator.The main components include a thermionic DC electron gun,an RF linear accelerator,a beam diagnostic chamber,and a beam exit window for electron beam irradiation.Therefore,reengineering must be performed based on the characteristics of the electron beam and its dynamics throughout the system.In this study,the electron beam current density emitted from the cathode was calculated based on the thermionic emission theory,and the result was used to produce the electron beam distribution in the gun using CST Studio Suite^(■)software.The properties of the electron beam and its acceleration in the linear accelerator and downstream diagnostic section were studied using the ASTRA electron beam dynamics simulation code,with the aim of producing an electron beam with an average energy of 4 MeV at the linear accelerator exit.The transverse beam profile and electron deposition dose in the ambient environment were calculated using Geant4 Monte Carlo simulation software to estimate the beam performance for the irradiation experiments.The parameters studied can be used as guidelines for machine operation and future experimental plans.
基金supported by the National Natural Science Foundation of China(82170481,82570069)Anhui Natural Science Foundation(2008085J39 and 2108085MH314)+1 种基金Anhui Province Innovation Team of Authentic Medicinal Materials Development and High Value Utilization(2022AH010080)Suzhou University Joint Cultivation Postgraduate Research Innovation Fund Project(2023KYCX04)。
文摘Chronic obstructive pulmonary disease(COPD)is a respiratory condition characterized by several symptoms.The pathogenesis of COPD is complex and involves multiple factors.A fantastic drug from traditional Chinese medicine,Isodon Suzhouensis(ISZ)is a perennial herb belonging to the Labiaceae family.It has the functions of resolving phlegm,removing stasis,promoting blood circulation and eliminating qi stagnation.ISZ has been found to possess great potential against COPD.Present study is focused on identifying micro RNA(mi RNA)biomarkers for COPD and determining the role of ISZ leaf extract in regulating the disease through mi RNA expression in serum exosomes.The Sprague Dawley(SD)rats were randomly divided into control group,COPD group and COPD+ISZ group.After the establishment of the model,the rats were sacrificed,and the results were compared with the control group.Then the total RNA of rat serum was extracted and identified by nanoparticle tracker.Finally,high-throughput screening and sequencing were performed to screen mi RNAs with significant differential expression.Then,different databases were used to figure out the possible target genes,and their functions were assessed by employing Gene Ontology(GO)as well as Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses.The sequencing results were then further verified by q RT-PCR.The results pointed out that these 17 differentially expressed mi RNAs may have the potential of diagnostic and prognostic biomarkers against COPD.Interestingly,it was also found that ISZ leaf extract may regulate the occurrence of COPD by affecting the expression of mi RNAs.This study identified the biomarkers of COPD and clarified the mechanism of the treatment of COPD by ISZ leaf extract,which is helpful to improve the level of early diagnosis and treatment of COPD.
基金supported by the National Research Council of Thailand(No.NRCT-5-RSA63004-16)Chiang Mai University.S.Pakluea acknowledges scholarship support from the Science Achievement Scholarship of Thailand(SAST).
文摘Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has focused on developing or improving THz sources,detectors,and applications.At the PBP-CMU Electron Linac Laboratory(PCELL)of the Plasma and Beam Physics Research Facility in Chiang Mai University,high-intensity THz radiation has been generated in the form of coherent transition radiation(TR)and investigated since 2006 for electron beams with energies ranging from 8 to 12 MeV.In this study,we investigate and optimize the coherent TR arising from short electron bunches with energies ranging from 8 to 22 MeV using an upgraded linear-accelerator system with a higher radio-frequency(RF)power system.This radiation is then transported from the accelerator hall to the experimental room,in which the spectrometers are located.Electron-beam simulations are conducted to achieve short bunch lengths and small transverse beam sizes at the TR station.Radiation properties,including the radiation spectrum,angular distribution,and radiation polarization,are thoroughly investigated.The electron-bunch length is evaluated using the measuring system.The radiation-transport line is designed to achieve optimal frequency response and high transmission efficiency.A radiation-transmission efficiency of approximately 80-90%can be achieved with this designed system,along with a pulse energy ranging from 0.17 to 0.25μJ.The expected radiation spectral range covers up to 2 THz with a peak power of 0.5-1.25 MW.This coherent,broadband,and intense THz radiation will serve as a light source for THz spectroscopy and THz time-domain spectroscopy applications at the PCELL in the near future.
基金funded by the Jiangsu Agriculture Science and Technology Innovation Fund,China(CX(12)5035)the National Natural Science Foundation of China(30971735)+1 种基金the China Agriculture Research System(CARS-18-20)the Special Fund for Agro-Scientific Research in the Public Interest of China(Impact of Climate Change on Agriculture Production of China,200903003)
文摘In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction（GGE） biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley（YaRV）, China. Four traits（cotton lint yield, fiber length, lint breaking tenacity, micronaire） and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments： a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none.
文摘Highly weathered soils are distributed in the humid and wet-dry tropics, as well as in the humid subtropics. As a result of strong weathering, these soils are characterized by low activity clays, which develop variable surface charge and related specific properties. Surface reactions regarding base exchange and soil acidification, heavy metal sorption and mobility, and phosphorus sorption and availability of the tropical highly weathered soils are reviewed in this paper.Factors controlling surface reactivity towards cations and anions, including ion exchange and specific adsorption processes, are discussed with consideration on practical implications for rational management of these soils. Organic matter content and pH value are major basic factors that should be controlled through appropriate agricultural practices, in order to optimise favorable effects of colloid surface properties on soil fertility and environmental quality.
文摘Severalα-glucosidase inhibitory constituents were isolated from the methanolic extract of the leaves of Quercus phillyraeoides A.Gray(Q.phillyraeoides)using a bioassay-guided fractionation technique.Further separation and purification of the methanol-soluble fraction led to the isolation of constituents with moderate and strong inhibitory activities againstα-glucosidase:α-sitosterol-d-glucoside(1)and condensed tannin fractions(2,3,4,5,and 6).Compound 1 and fractions 2-6 had inhibitory concentration(IC50)values againstm-glucosidase from Saccharomyces cerevisiae of 118.8,2.79,2.78,3.10,2.60,and 3.14μg/mL,respectively,while quercetin as the standard had an IC50 value of 4.80mg/mL.Furthermore,the significant antioxidant activities were evaluated using several assays,such as the DPPH radical scavenging,hydrogen peroxide radical scavenging,reducing power,andβ-carotene-linoleate bleaching assays,and the results suggested that the isolated constituents showed their possible application for treating the hyperglycemia-induced oxidative stress.The results of the present study showed the potential of Q.phillyraeoides as a rich source of natural antidiabetic medicine.
文摘This study of the impact of heart rot of <i><span style="font-family:Verdana;">Pericopsis elata</span></i><span style="font-family:Verdana;"> on logging yield was conducted in Libongo, in three logging concessions of the </span><i><span style="font-family:Verdana;">Société d'Exploitation Forestière et Agricole du Cameroun</span></i><span style="font-family:Verdana;"> (SEFAC). An inventory of 92 </span><i><span style="font-family:Verdana;">P. elata</span></i><span style="font-family:Verdana;"> stumps in four Annual Cutting Areas (AACs) divided among three Forest Management Units (FMUs) distinguished by Minimum Operating Diameter </span><span style="font-family:Verdana;">(MOD) revealed that 22 stumps were rotten. Decay was visible on stumps wit</span><span style="font-family:Verdana;">h a diameter of more than 100 cm with a frequency of occurrence of 23.91%, a percentage of abandonment of 55.20% and a yield of 44.79%. The most important economic loss was revealed on 9 abandoned whole logs that cumu</span><span><span style="font-family:Verdana;">lated a volume of 145.547 m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">. The correlation between the diameter of the</span></span><span style="font-family:Verdana;"> stumps and that of the decay gives a coefficient or correlation rate r = 0.31. The MOD for </span><i><span style="font-family:Verdana;">P. elata</span></i><span style="font-family:Verdana;"> could be 80 cm and covers the biological risk class. The results indicate that </span><i><span style="font-family:Verdana;">P. elata</span></i><span style="font-family:Verdana;"> shows an increasing gradient of decay rate with increasing tree diameter, resulting in a loss of material for larger diameter trees, and consequently a decrease in material yield at processing.</span>
文摘This study was carried out in the forest reserve of Mbalmayo, Center Region of Cameroon, with the aim to analyze the dynamics of land use/land cover (LULC) changes over the past 30 years. The databases used were made up of 3 Landsat satellite images (5TM of 1990, 7ETM+ of 2005 and 8OLI of 2020). The satellite images were processed using ArcGIS and Erdas Imagine software. Ethnobotanical surveys were conducted to investigate the relationships between the local population and the forest reserve. The Mbalmayo forest reserve is consisted of seven main land cover namely: mature secondary forest, young secondary forest, savanna, fallows and crops, built, bare soil and water surface. The dynamics of the forest cover undergoes more significant changes between the years 1990-2005 with losses estimate at 4762 ha compared to the years 2005-2020 (2231 ha), with a marked decrease in the area of dense forests. This regression is much more important in dense forest vegetation. The forest cover lost 6993 ha (26.92%) of its surface, which corresponds to an average rate of deforestation of 233.1 ha/year. The survey revealed the need for NTFPs for the Mbalmayo reserve forest populations. Indeed, all respondents agreed that they use non-timber forest products from the forest, mainly for medication (37%), wood (34%) and food (24%). Therefore, it becomes urgent to redefine a management plan for the Mbalmayo forest reserve which will define how the forest must be managed in order to avoid the loss of large areas of forests disappearing each year under the human action, which exerts pressure on forest species, thus leading to their possible disappearance.
文摘Sorghum bicolor is among main staple crops of Chad but it is commonly attacked by Striga hermonthica. Assessment of sorghum varieties for resistance to this weed was carried out during three cropping seasons （2005-2008）, in controlled conditions; promising entries （those which fulfilled at least 75% of selection criteria） were evaluated in farmer field in 2008-2009 seasons. There were five sites （Bebedjia, Deli, Bekao, Koudoti and Ndaba）. The objective was to evaluate some sorghum entries for S. hermonthica resistance in farmer field. Sorghum test was composed of four entries in Fisher blocks as experimental designs, with five replications. Among different observed variables, there were striga plant count and weight of sorghum grains. One promising entry was selected at Bebedjia and Ndaba （53）, two at Deli and Koudoti （50 and 53）. No entry was selected at Bekao. Promising entries for the whole Southern zone of Chad were composed of 50 and 53. The best entry was 53 because it was promising in all sites except Bekao.
文摘An investigation to assess the spatial structure and severity of Pseudocercospora leaf and fruit spot disease (PLFSD) on citrus trees in cocoa-based agroforests was carried out in three contrasting ecological zones in southern Cameroon, viz: 1) the humid forest zone, 2) the degraded forest zone, and 3) the forest-savannah transition zone. Two main parameters were investigated viz: 1) the spatial structure of cocoa based agroforests, and 2) the disease severity. In total, the spatial structure of 19 cocoa-based agroforests was analysed using the Ripley K(r) function, meanwhile the collection of epidemiological data that consisted of noting the presence of PLFSD spots on leaves and fruits on 438 citrus trees was used to characterise the severity of the disease. Results showed that, the spatial structure of citrus trees in these agroforests investigated were regular in seven plots, random in nine, and aggregated in three. Aggregated plots presented a significantly higher mean of disease severity on leaves and fruits (28.55 and 30.37 respectively), as compared to randomised (20.91 and 16.32 respectively) and regular plots (16.28 and 14.97 respectively), at P-value < 0.05. These results suggest that the spatial structure of citrus trees in the cocoa-based agroforests studied influences the severity of PFLSD. Proper integrated control measures can therefore be initiated, leading to a considerable reduction of the use of manufactured inputs, and thereby, the cost of production of citrus fruits.
文摘This study emphasizes the formulation of three types of cookies viz potato flour with date powder and bean milk (PDBM), potato flour with sugar and bean milk (PSBM), and potato flour, sugar, and eggs as control. After the substitution, the highest protein content was observed in PDBM (1.78 ± 0.12)% followed by PSBM, (1.35 ± 0.01)% and the lowest was in the control (0.91 ± 0.55)%. Moreover, cookies fortified with date palm powder increased the carbohydrate and fat contents compared to the control and significantly increased the calorific value of PDBM. The formulated cookies were significantly higher (p < 0.05) in iron (39.95 ± 3.00) mg/100 g and zinc (13.65 ± 1.61) mg/100 g in PDBM compared to other cookies. The date palm powder incorporated in cookies significantly increases the darkening of biscuits during cooking. The organoleptic characteristics of PDBM and PSBM were rated overall best when specific parameters were tested. With the shortage of wheat and importation constraints, an alternative provides a great market opportunity for local products like potatoes and beans. In addition, fortifying food products as cookies eaten by all will contribute to a more food and nutrition-secured world.
文摘The purpose of the study was to establish the structure of monitored animal farms and determine reproductive parameters of Sahelian goats in the Guera Region, in Central Chad. Data were collected through longitudinal survey in 27 observatory farms during three years using goats identified by numbered ear tags. The herds were composed on average of about 71% of females. The age pyramid covering all years showed a significant number of males aged between 0 - 1 year and perceptible fall thereafter. However, some stability was observed in the class of the 2 - 8 years old among females. The frequencies of accumulated kiddings showed that 44% of births occurred in the rainy season against 28% respectively in the cool dry and hot dry seasons. Obtained reproduction parameters were: a sex ratio of 0.51 in favor of males, a kidding interval of 10.6 months with significant differences (P < 0.05) according to the rank of birth, an age at first kidding of 16.5 months for females born in monitoring and an age of 20.3 months for all first-kidding, giving an apparent fertility rate of 145%, a fecundity rate of 116% and an abortion rate of 2%. The composition and structure of herds have highlighted the importance of females to ensure the reproducibility of goat production systems. The determined reproduction parameters are references for actions to improve goat rearing in this area.
文摘<span style="font-family:Verdana;">In order to contribute to the improvement of the knowledge on the</span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> valorization of biochar as a feed additive in livestock, three biochar made from cassava peelings, bean tops and cocoa pods were manufactured. After analyzing their mineral composition, they were incorporated into rations at a rate of 0.8% in order to evaluate their effects on the performance of reproduction and pre-weaning growth in cavy (</span><i><i><span style="font-family:Verdana;">Cavia</span></i><span> <i><span style="font-family:Verdana;">porcellus</span></i><span style="font-family:Verdana;"></span></span></i></span></span><span style="font-family:Verdana;">). The trials were conducted in the Research Unit of Animal Production and Nutrition (URPRONAN) of the University of Dschang, on 96 adult local breed cavy (from the first generation), including 80 females and 16 males aged 4 months and with an average weight of 400 ± 0.25 g. After 2 weeks of adaptation in the rearing boxes at the farm, the females were put in reproduction for a period of 31 days, the animals were divided into 04 batches of 20 females and 4 males. The animals in the control lot were fed a compound feed without biochar (T) while the oth</span><span style="font-family:Verdana;">ers were fed the compound feed containing 0.8% of cassava peel biochar</span><span style="font-family:Verdana;"> (EM), 0.8% of bean tops biochar (FH) and 0.8% of cocoa pod husks biochar (CC) respectively. The results of this study showed that the ash content (26%) and macro-element concentration were higher in the bean husk charcoal compared to the other charcoals and the trace elements were more concentrated in the cassava peel charcoal. The best fertility rate (87.5%) was obtained in </span><span style="font-family:Verdana;">animals receiving the ration containing organic cocoa pod charcoal. The</span><span style="font-family:Verdana;"> highest abortion rate (63.16%) was obtained in the batch of animals receiving the </span><span style="font-family:Verdana;">ration containing organic bean husk charcoal. Pre-weaning mortality rates </span><span style="font-family:Verdana;">were comparable between the different rations. Piglet weights at birth were comparable between the different rations. At weaning, the highest average weight of the kids was recorded with the ration containing the organic bean charcoal (197.25 ± 46.9 g). The highest ADG (4.82 ± 0.74 g/d) and TG (101.25 g) were recorded in the batch of animals receiving the FH ration. Thus, the incorporation of 0.8% of the powder of organic coals seems to have adverse effects on reproductive performance. On the other hand, these coals significantly improve the pre-weaning growth performance in cavy.</span></span>
文摘Trypanosomosis remains the number one killer of livestock in spite of efforts made to eradicate tsetse flies in the Adamawa plateau of Cameroon. Acetone-baited Laveissière type biconical traps were pitched at 100 meter intervals in strategic geo-referenced positions in various ecological niches of the landscape for 5 consecutive days in selected villages in Mayo Rey, Mbere, Vina and Faro et Deo divisions. All 493 tsetse flies captured in sites other than Mboula wereG. morsitans submositans.Measurement of different morphometric characters on the wings of each individual fly was undertaken using the Du Jardin package. The data was processed and analysed by “Permutaciones, Analisis Discriminante (PAD)” and “Bootstraps, Analisis en Componentes principales”. The three major sampling sites on the plateau yielded similar results as demonstrated by the neighbour joining tree of Mahalanobis distances but tests using PAD showed the differences between group means to be significant
文摘The effects of climate change have had a major impact on forage availability in the Sahel and Saharan regions of Chad in recent years. This has led to the migration of farmers in search of long-distance grazing, thus impacting the potential of the animals to produce good quality milk and meat. It is with this in mind that this study was conducted on the knowledge of feeding practices of animals in the provinces of Wadi-Fira and West-Ennedi (Chad) during the lean period. More specifically, it is a question of collecting some information on the plants consumed by the animals and the way in which the breeders formulate the food ration of their herds in times of deficit. It emerges from this investigation that the herds of animals in the province of Wadi-Fira faced with forage deficit and adapted by consuming the leaves, fruits and seeds of certain tropical plants such as Capparis decidua, Ziziphus mauritiana, Balanites aegyptiaca, Acacia tortilis, Boscia senegalensis, Salvadora percica and Tribulis terristris to compensate for food shortages. This same observation was made in the province of West-Ennedi, since this area is desert with annual precipitation of 150 mm. Natural pasture is only available around water points (ouadis and oasis) in a small area with a high number of herds. Thus, the herds also face a drastic lack of grazing during the deficit periods. However, they adapt by consuming the leaves, fruits and seeds of plants such as Bauhinia sp., Boscia senegalenis, Acacia tortilis, Tribulis terristris, Boscia angustifolia, Bicoma tomentosa, Blepharis linarifolia and Aristida funiculata during lean periods to meet their food requirements. The formulation of the feed ration for animals differs from one area to another. It is mainly based on residues from cereals such as millet (Panicum miliaceum) and sorghum (Sorghum bicolor).
文摘The Sudanian-Sahelian zone of the Far-North Cameroon faces an extreme climate challenge resulting in increased vulnerability to erosion, soil degradation, and the effects of climate change, impacting soil fertility and agricultural yields. The objective of this study was to analyze agricultural practices, challenges related to climate change and soil degradation, as well as the solutions adopted by farmers to address these issues. To achieve this, 600 farmers from the six departments of the region were interviewed. The results highlight the significant impact of climatic conditions on soil health, agricultural activities, and food security. Farmers identified various indicators of soil degradation, including agricultural yields, bioindicator plants, plant growth, soil fauna, and root density. The main causes of soil degradation are associated with practices such as deforestation, intensive agriculture, the use of chemical fertilizers and pesticides, overgrazing, and the effects of climate change. The impacts of this degradation are multiple, including soil fertility loss, reduced agricultural yields, deforestation, reduced biodiversity, income loss, water resource pollution, and food insecurity. In response to these challenges, farmers have adopted sustainable soil management practices, including crop rotation, intercropping, fallowing, the use of organic fertilizers, and the adoption of conservation agriculture. To effectively address these challenges, concerted collaboration between farmers, civil society organizations, and government authorities is imperative to develop sustainable and effective solutions against soil degradation in the region.
