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Occasional Tillage in a Field Established under Conservation Agriculture for Tomato Cropping
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作者 Roberto Botelho Ferraz Branco Bruno Cesar Ananias +2 位作者 Andréia Cristina Silva Hirata Humberto Sampaio de Araújo Jane Maria de Carvalho Silveira 《Agricultural Sciences》 2025年第1期31-47,共17页
The Conservation Agriculture (CA) is a current concept drives to save natural resources for agricultural production based on the minimum soil disturbance or no-tillage, crop rotation and permanent maintenance of straw... The Conservation Agriculture (CA) is a current concept drives to save natural resources for agricultural production based on the minimum soil disturbance or no-tillage, crop rotation and permanent maintenance of straw on soil surface. The increasing in soil density is a problem to achieve great copping yield under CA, so occasional one-time tillage is considered as an alternative to continuous no-tillage. In this way, this experiment was carried out to compare occasional tillage and no-tillage interacting with cover crops in a field established under conservation agriculture. Thus, the experimental treatments were set up by two tillage methods, conventional tillage and no-tillage and two cover crops, white lupin and millet setting in a randomized blocks with split plot design with four replications. The traits evaluated in the research were soil fertility, soil resistance to penetration, soil moisture and tomato agronomic performance. No-tillage was more efficient to preserve soil moisture;however soil fertility, soil resistance to penetration and tomato yield were favored by conventional tillage. Regarding to cover crops white lupin increased the soil K concentration and enhanced the tomato growth. Although occasional tillage had better performance to the soil fertility and tomato yield, we highlighted that CA is the better way to increase soil health and soil and water conservation along the time leading to so desired regenerative agriculture. 展开更多
关键词 No Tillage Crop Rotation Cover Crops Solanum lycopersicum L.
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Feeding amylolytic and fibrolytic exogenous enzymes in feedlot diets:effects on ruminal parameters,nitrogen balance and microbial diversity of Nellore cattle
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作者 Igor Machado Ferreira Hilario Cuquetto Mantovani +12 位作者 Fiorella Viquez-Umana Yury Tatiana Granja-Salcedo Luiz Fernando Costa e Silva Anne Koontz Vaughn Holder James Eugene Pettigrew Arlan Araujo Rodrigues Aline Naime Rodrigues Mateus Jose Inacio de Abreu Saulo Teixeira Rodrigues de Almeida Pedro Marcus Pereira Vidigal Gustavo Rezende Siqueira Flavio Dutra de Resende 《Journal of Animal Science and Biotechnology》 2025年第6期2802-2819,共18页
Background The environmental impact of feedlot operations is a growing concern,as cattle excrete a significant portion of feed nutrients as waste.Exogenous feed enzymes(EFE)have gained interest for their potential to ... Background The environmental impact of feedlot operations is a growing concern,as cattle excrete a significant portion of feed nutrients as waste.Exogenous feed enzymes(EFE)have gained interest for their potential to enhance feed efficiency in ruminants by improving nutrient digestion.However,EFE effects on ruminal parameters have shown inconsistencies,with limited research on nitrogen metabolism and rumen microbiome impacts.Moreover,the synergistic effects of combining different EFEs remain unclear.This study aimed to evaluate the effects of individual and combined EFE products in feedlot diets on ruminal fermentation parameters,nitrogen metabolism,and ruminal microbial communities.Ten rumen-cannulated Nellore steers[543±28.6 kg of body weight(BW)]were distributed in a replicated Latin-square design(5×5)in individual pens.Treatments included:control(CON,no EFE supplementation),amylase[AML,0.5 g/kg of diet dry matter(DM)],xylanase(FBL,0.9 g/kg DM),half dose combination(HD,0.25 g of AML+0.45 g of FBL/kg of DM),and full dose combination(FD,0.5 g of AML+0.90 g of FBL/kg of DM).The experimental period lasted 19 d and included total urine and feces collection(d 15 to 18)and rumen fluid sampling(d 19)at 0,4,8,12,and 16 h post-feeding for ammonia,volatile fatty acids(VFA),pH and microbiome analysis.Results EFE supplemented animals exhibited lower ruminal ammonia concentrations(P=0.040),and higher acetate proportions(P<0.001)compared to the control group.EFE supplementation resulted in reduced nitrogen(N)excretion in feces(P=0.049)and urine(P=0.036),contributing to improved N retention and efficiency(P=0.045).Additionally,EFE products induced shifts in various microbial taxa at family and genera levels(P≤0.10),which may be associated with the changes observed in ruminal fermentation.Conclusions Our findings demonstrate that EFE supplementation enhances nitrogen retention,reduces ruminal ammonia,and alters ruminal fermentation profiles and microbial populations in feedlot cattle.While the expected synergism between amylase and xylanase did not significantly impact rumen fermentation parameters,it did induce shifts in the rumen microbiome.These results suggest that EFE supplementation may be a promising strategy for improving nutrient utilization and potentially reducing the environmental impact of feedlot operations. 展开更多
关键词 Amylolytic enzymes Beef cattle Fibrolytic enzymes Nitrogen metabolism Rumen microbiome
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Assessing the relationship between the rumen microbiota and feed efficiency in Nellore steers 被引量:4
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作者 Déborah Romaskevis Gomes Lopes Márcio de Souza Duarte +8 位作者 Alex J.La Reau Ibrahim Zuniga Chaves Tiago Antônio de Oliveira Mendes Edenio Detmann Cláudia Braga Pereira Bento Maria Eugênia Zerlotti Mercadante Sarah Figueiredo Martins Bonilha Garret Suen Hilário Cuquetto Mantovani 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第4期1645-1661,共17页
Background:Ruminants rely upon a complex community of microbes in their rumen to convert host-indigestible feed into nutrients.However,little is known about the association between the rumen microbiota and feed effici... Background:Ruminants rely upon a complex community of microbes in their rumen to convert host-indigestible feed into nutrients.However,little is known about the association between the rumen microbiota and feed efficiency traits in Nellore(Bos indicus)cattle,a breed of major economic importance to the global beef market.Here,we compare the composition of the bacterial,archaeal and fungal communities in the rumen of Nellore steers with high and low feed efficiency(FE)phenotypes,as measured by residual feed intake(RFI).Results:The Firmicutes to Bacteroidetes ratio was significantly higher(P<0.05)in positive-RFI steers(p-RFI,low feed efficiency)than in negative-RFI(n-RFI,high feed efficiency)steers.The differences in bacterial composition from steers with high and low FE were mainly associated with members of the families Lachnospiraceae,Ruminococcaceae and Christensenellaceae,as well as the genus Prevotella.Archaeal community richness was lower(P<0.05)in p-RFI than in n-RFI steers and the genus Methanobrevibacter was either increased or exclusive of p-RFI steers.The fungal genus Buwchfawromyces was more abundant in the rumen solid fraction of n-RFI steers(P<0.05)and a highly abundant OTU belonging to the genus Piromyces was also increased in the rumen microbiota of highefficiency steers.However,analysis of rumen fermentation variables and functional predictions indicated similar metabolic outputs for the microbiota of distinct FE groups.Conclusions:Our results demonstrate that differences in the ruminal microbiota of high and low FE Nellore steers comprise specific taxa from the bacterial,archaeal and fungal communities.Biomarker OTUs belonging to the genus Piromyces were identified in animals showing high feed efficiency,whereas among archaea,Methanobrevibacter was associated with steers classified as p-RFI.The identification of specific RFI-associated microorganisms in Nellore steers could guide further studies targeting the isolation and functional characterization of rumen microbes potentially important for the energy-harvesting efficiency of ruminants. 展开更多
关键词 Beef cattle ITS1 region Next-generation sequencing RFI Rumen microbiota 16S rRNA gene
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Evaluation of Four Methods for Restoring a Degraded Swamp Forest 被引量:2
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作者 Gisele Mondoni Marconato Rita C. S. Maimoni-Rodella Claudia Mira Attanasio 《Open Journal of Forestry》 2015年第5期500-509,共10页
Swamp Forests occur in permanently wet soils, with specific ecosystem which contributes to the conservation of biodiversity and water resources. However, there are many gaps in knowledge about the restoration of these... Swamp Forests occur in permanently wet soils, with specific ecosystem which contributes to the conservation of biodiversity and water resources. However, there are many gaps in knowledge about the restoration of these forests. The present study was conducted in a degraded wetland in the town of Mineiros do Tietê, located in the state of S?o Paulo, Brazil, in order to test the efficiency of four methods for restoring a Swamp Forest (small mound, acclimated seedling, dry season and conventional tillage), using six forest tree species typical of this type of forest: Calophyllum brasiliense Cambess., Citharexylon myrianthum Cham., Cedrela odorata L., Tapirira guianensis Aubl., Ficus insipida Willd. and Croton urucurana Baill. The least favorable methods for all plant species were: conventional and soil pit tillageindry seasons. Analyzing the plant species individually, the best results in descending order were: Croton urucurana Baill. (acclimated seedling tillage in dry season), followed by Calophyllum brasiliense Cambess. (insmall mounds), Citharexylon mirianthum Cham. (with acclimated seedlings), Ficus insipida Willd. and Tapirira guianensis Aubl. (insmall mounds). Cedrela odorata L. presented low performance in all conditions, probably because it suffered the Hypsipyla grandella Zeller. The results have been successful for the establishment of Swamp Forest restoration strategies. 展开更多
关键词 RESTORATION METHODS ACCLIMATIZATION Soil Water SATURATION RIPARIAN ZONE
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The role of green manure nitrogen use by corn and sugarcane crops in Brazil 被引量:3
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作者 Edmilson José Ambrosano Heitor Cantarella +4 位作者 Gláucia Maria Bovi Ambrosano Fábio Luis Ferreira Dias Fabrício Rossi Paulo Cesar Ocheuze Trivelin Takashi Muraoka 《Agricultural Sciences》 2013年第12期89-108,共20页
Three assays were developed from April 3, 1995 to October 10, 2005. The work with corn was conducted in a greenhouse, using velvet bean (Mucuna aterrima) and sunn hemp (Crotalaria juncea) as green manure with 15N labe... Three assays were developed from April 3, 1995 to October 10, 2005. The work with corn was conducted in a greenhouse, using velvet bean (Mucuna aterrima) and sunn hemp (Crotalaria juncea) as green manure with 15N labeling of either shoots or roots, in two soils with contrasting textural classes. The mineralization of N from legume plants incorporated into the two soils was investigated too. This work included two green manures: velvet bean and sunn hemp, and the common bean (Phaseolus vulgaris) residues. Nitrogen from the velvet bean accounted for a greater proportion of the soil inorganic N;shoots were responsible for most of N accumulated. Common bean residues caused immobilization of inorganic N. The leguminous species added were intensively and promptly mineralized, preserving the soil native nitrogen. One hundred days after emergence of the corn, velvet bean provided higher accumulation of nitrogen in the soil, higher absorption by corn plants and accumulation in the aerial part. The green manure decomposition was more intense in the medium textured soil. In this soil, highest nitrogen losses were also observed. The sugarcane (Saccharum spp.) was cultivated for five years in the field and was harvested three times;15N recovery was evaluated in the first two harvests. The combination of inorganic fertilizer and green manure resulted in higher sugarcane yields than either N source applied separately;however, in the second cutting the yields were higher where sunn hemp was used than in plots with ammonium sulfate. The recovery of N by the first two consecutive harvests accounted for 19% to 21% of the N applied as sunn hemp and 46% to 49% of the N applied as ammonium sulfate. Very little inorganic N was present in the 0-40 cm soil layer with both N sources. 展开更多
关键词 Saccharum spp. Biological Nitrogen Fixation 15N Isotope Technique N-MINERALIZATION Mineral Nitrogen
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The Role of Nitrogen Fertilizers in Sugarcane Root Biomass under Field Conditions 被引量:3
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作者 Rafael Otto Henrique Coutinho Junqueira Franco +4 位作者 Carlos Eduardo Faroni André Cesar Vitti Emídio Cantidio Almeida de Oliveira Renata Alcarde Sermarini Paulo Cesar Ocheuze Trivelin 《Agricultural Sciences》 2014年第14期1527-1538,共12页
Sugarcane is used worldwide for sugar, ethanol and energy production. In Brazil, the shift from burned to unburned harvest systems resulted in increases in nitrogen fertilization rates, which can impact root architect... Sugarcane is used worldwide for sugar, ethanol and energy production. In Brazil, the shift from burned to unburned harvest systems resulted in increases in nitrogen fertilization rates, which can impact root architecture and biomass. The expectation is also an increase in sugarcane biomass. The study hypothesized that high N rates applied to sugarcane fields increases root growth and N stored in roots, promoting higher biomass and N accumulated in shoots. Two experiments were set up in Southeastern Brazil, on a Typic Kandiudox (TK) and Rhodic Eutrudox (RE). Four treatments were studied 1) N application in the plant-cane (0 and 120 kg·ha-1 N) and 2) N application in the ratoon (0 and 150 kg·ha-1 N). The shoot biomass and the root density (by the core method up to 0.6 m) were evaluated over the first ratoon crop cycle, and the N content in those compartments was also examined. There was no carry over effect on N applied at planting in root and shoot biomass in the ratoon crop cycle. At the RE site, the ratoon N fertilization increased root density in the superficial soil layer (0 - 0.2 m) and close to the plants (<0.3 m). The effect of N addition on root biomass, and biomass and N accumulated in shoot was limited in both sites. Increasing N rates in unburned sugarcane fields do not consistently increases root and shoot biomass under Brazilian field conditions. 展开更多
关键词 ROOT System RATOON SHOOT Root: SHOOT RATIO
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Effect of Infestation of <i>Alabama argillacea</i>(Lepidoptera: Noctuidae) at Different Ages of Cotton Plants in Yield
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作者 Marcos Doniseti Michelotto Jacob Crosariol Netto +4 位作者 José Fernando Grigolli Antonio Carlos Busoli Willians Cesar Carrega Everton Luis Finoto Juliana Altafin Galli 《American Journal of Plant Sciences》 2014年第10期1441-1448,共8页
The cotton leafworm is an important defoliating pest of cotton in Brazil, and occurs in all regions where the crop is cultivated. The purpose of this study was to evaluate the effect of larval densities of A. argillac... The cotton leafworm is an important defoliating pest of cotton in Brazil, and occurs in all regions where the crop is cultivated. The purpose of this study was to evaluate the effect of larval densities of A. argillacea after different infestation periods on the yield components of four cotton cultivars. The experiment was carried out in Pindorama, SP, Brazil, in the 2008/2009 growing season. The cultivars IAC-25, DeltaOPAL, Fibermax 966 and Fibermax 993 were artificially infested with A. argillacea larvae at three times (30, 60 and 90 DAE) and four densities (0, 2, 4, and 6 larvae per plant). The average boll weight (g), fiber percentage (%), 100-seed weight (g) and yield (kg·ha-1) were evaluated. With increasing infestation density of A. argillacea, the cotton yield of the cultivars decreased. The presence of larvae significantly reduced the weight of 100 seeds of cultivar Fibermax 966. Initial infestations reduced the boll weight of IAC-25 and DeltaOPAL, while cultivars Fibermax 966 and Fibermax 993 were most affected by late infestations. Early infestation compromised fiber percentage of cultivar DeltaOPAL and late infestations were most harmful to cultivar Fibermax 966. Early A. argillacea infestation reduced the yield of DeltaOPAL, while infestations 60 DAE caused the most damage to IAC-25, and the other cultivars were not affected by the moment of infestation. 展开更多
关键词 GOSSYPIUM hirsutum Cotton Leafworm Cultivars Biotic Stress
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Macauba as Promising Substrate for Crude Oil and Biodiesel Production
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作者 Roseli Aparecida Ferrari Joaquim Adelino de Azevedo Filho 《Journal of Agricultural Science and Technology(B)》 2012年第10期1119-1126,共8页
The preparation of macauba fruits (Acrocomia aculeate (Jacq.) Lodd. ex Martius) both for oil extraction by continuous pressing and biodiesel production were investigated. The fruits and its pulp and kernel were ch... The preparation of macauba fruits (Acrocomia aculeate (Jacq.) Lodd. ex Martius) both for oil extraction by continuous pressing and biodiesel production were investigated. The fruits and its pulp and kernel were characterized for their resulting oils. Experimental design was carried out to study the transesterification of each oil to obtain the concentrations of ethanol and catalyst that would provide the best biodiesel yield. A higher amount of biodiesel was produced from the best conditions to evaluate some characteristics as specified by ANP (National Agency of Petroleum, Natural Gas and Biofuels). The results showed a variation in the fruits composition and different characteristics presented by the pulp and kernel oil. It was possible to define technological steps to obtain oil from the fruits of macauba and find the optimal conditions to biodiesel production, concentration of catalyst 4.42% and 5% and 13.3:1 and 9:1 ethanol:oil molar ratio to kernel oil and pulp oil, respectively. 展开更多
关键词 Acrocomia aculeata oil extraction pulp and kernel oil.
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Damage Caused by Psyllids and Influence of Climatic Factors in Brazilian Accesses of Guava Trees Cultivated in Organic System
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作者 Juliana Altafin Galli Marcos Doniseti Michelotto +2 位作者 Maria Beatriz Bernardes Soares Antonio Lucio Melo Martins Ivan Herman Fischer 《American Journal of Plant Sciences》 2014年第10期1432-1440,共9页
The psyllid (Triozoida sp.) is the primary pest of guava tree in the Central Northern region of S?o Paulo State, Brazil. The variation of climatic factors may influence directly or indirectly the behavior of agricultu... The psyllid (Triozoida sp.) is the primary pest of guava tree in the Central Northern region of S?o Paulo State, Brazil. The variation of climatic factors may influence directly or indirectly the behavior of agricultural pests. The present work had objectives to evaluate the damages caused by psyllid in accesses of guava trees in order to identify materials with potential resistance to pest and the possible correlations of the damage with the meteorological factors, in an orchard of guava conducted in an organic system. Eighty-five guava accesses were evaluated. Each one was analyzed at random 10 leaves containing the symptom of the psyllid attack, through visual range of notes. The averages of the notes were compared by Scott-Knott test at 5% probability. The 25 accesses with the highest average damage of psyllid had the data submitted to correlation (Pearson), with the minimum and maximum temperature (°C), precipitation (mm) and relative humidity (%). Guava accesses used commercially were the most susceptible to the attack of psyllid, compared to the selections, with an emphasis to access “L4P14”, “L7P28” and “L8P32B”, which were the least attacked. The study of correlation between psyllid damages and meteorological factors, must be used the medium temperature, relative humidity and rainfall accumulated in the period of 14 days before the evaluations. There is a positive correlation between minimum temperasture, precipitation and relative humidity with the damage of psyllids in leaves of guava. 展开更多
关键词 Triozoida sp. Psidium guajava Varietal Resistance Temperature PRECIPITATION Relative Humidity
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可持续的不锈钢交通运输建筑设计
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作者 凯瑟琳.胡斯卡 《建筑技艺》 2010年第2期92-101,共10页
引人注目且具可持续性的交通运输建筑设施是当代讲求效率的基础设施建筑中的重要组成部分。除拥有夺目的外观外,经正确选择的不锈钢具有更佳的耐久性,维护要求最少,可长期安全使用并保持安防和交通控制的功能。不锈钢这些特性及其内在... 引人注目且具可持续性的交通运输建筑设施是当代讲求效率的基础设施建筑中的重要组成部分。除拥有夺目的外观外,经正确选择的不锈钢具有更佳的耐久性,维护要求最少,可长期安全使用并保持安防和交通控制的功能。不锈钢这些特性及其内在的可持续性,使其成为世界范围内新建交通设施的重要设计材料。因此,重新审视不锈钢的应用、优点及规格将给设计者以信心,在那些设计使用寿命50年以上的作品中选用不锈钢材料进行设计。 展开更多
关键词 不锈钢 可持续 可循环利用成分 减少热量吸收 屋顶径流
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Physical Dynamics and the Influences of the Environment Built on Subbasins
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作者 Karla Conceicao Pereira Alcindo Neckel +1 位作者 Caliane Christie Oliveira de Almeida Silva Vladimir Stolzenberg Torres 《Journal of Civil Engineering and Architecture》 2018年第1期65-74,共10页
The fields of engineering, architecture and urbanism ought to ponder on constructive changes to be employed in the environment. Environmental vulnerability usually reaches sites with greater abundance of water resourc... The fields of engineering, architecture and urbanism ought to ponder on constructive changes to be employed in the environment. Environmental vulnerability usually reaches sites with greater abundance of water resources that are exposed to contaminable factors, which usually become residential expansion areas, and often extrapolate city boundaries. The general objective of this study is to assess physical characteristics of the subbasins of the Curtume and Agua Preta streams, located in the Paraiba do Sul watershed in the municipality of Pindamonhangaba, in the state of Sao Paulo (SP), Brazil. The current situation regarding this environment, based on soil type and morphometric and physiographic attributes, is specifically sought to be identified. The results show the morphological and physiographic relationships with the hydrological data that determine the natural pattern of the site, associated with anthropic actions that characterize potentialities and vulnerabilities of the area, thus determining environmental dynamics. The results demonstrate that urban sprawl and residential constructions in subbasin conservation areas should occur in a planned and strategic manner, without advancing to water conservation areas. 展开更多
关键词 WATERSHED urban expansion physical analysis environmental conservation.
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Infestation of Diatraea saccharalis(Fabr.)during Five Consecutive Cycles of Sugarcane Crop Succeeding Leguminous Crops
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作者 Edmilson Jose Ambrosano Andre Luiz Lourencao +4 位作者 Elaine Bahia Wutke Fabricio Rossi Fabio Luis Ferreira Dias Silvio Tavares Glaucia Maria Bovi Ambrosano 《Agricultural Sciences》 2015年第1期14-21,共8页
The area cultivated with sugarcane in Brazil is expanding, and increasingly using legumes cover crop in new deployed areas and in those which were reformed. Long-term trials were carried out in Piracicaba, Sao Paulo, ... The area cultivated with sugarcane in Brazil is expanding, and increasingly using legumes cover crop in new deployed areas and in those which were reformed. Long-term trials were carried out in Piracicaba, Sao Paulo, Brazil, to evaluate the effect of leguminous green manure on the natural infestation of Diatraea saccharalis (Fabr.) during five cropping cycles of sugarcane “IAC 87-3396”. This study was carried out from October 1999 to October 2005 in Piracicaba, Sao Paulo, Brazil, at coordinates 22°42''S and 47°38''W, 560 m above sea level, in soil classified as Typic Paleudult. Green manure crops were assigned to five treatments: peanuts (Arachis hypogaea L.) (cultivar “IAC-Tatu” and “IAC-Caiapó”), sunn hemp (Crotalaria juncea L.) (cultivar “IAC 1”) and velvet-bean [Mucuna aterrima (Piper & Tracy) Holland] (cultivar “common”). A treatment without any green manure or weed was used as the control. The previous sugarcane crop was destroyed and the soil was prepared in a conventional way (using plow and harrow) before the leguminous crops were sowed. Thirty days after the sowing, weeds were removed and, 120 days later, the crops were cut and its biomass was deposited on the soil surface without incorporation. Experimental plots comprised five rows of sugarcane, each one measuring 10 m long and spaced 1.40 m apart. The sugarcane was harvested 18 months after biomass deposit, on October 25th, 2001 and its stalks were collected at intervals of approximately 12 months in: 07/09/2002, 08/01/2003, 11/07/2004 and 10/06/2005. At harvest, the masses were determined from a sample of sugarcane, cut from three rows (2 m long) in the center of the plot. The losses caused by the sugarcane borer were estimated by the intensity of the infestation by randomly observing and collecting sugarcane stems from each plot. A great reduction in the number of stalks and in the yield was noted proportionally to the intensity of the infestation of the borer in the sugarcane crop grown after the velvet-bean. The sugarcane-velvet-bean rotation should be regarded considering the intensity of sugarcane borer infestation. No influence of the other green manure crops was observed on the intensity of the infestations. However, the harvest seasons of the sugarcane seemed to influence the borer infestation. 展开更多
关键词 Arachis hypogaea L. Crotalaria juncea L. Mucuna aterrima(Piper&Tracy)Holland Saccharum spp. Sugarcane Borer
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Response of Moderate Pest Resistant and Susceptible Cultivar of Sugarcane to Silicon Application
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作者 Michelle Vilela Jair Campos Moraes +3 位作者 Mariane Coelho Jonas Francoso Terezinha Monteiro dos Santos-Cividanes Roney Sakomura 《American Journal of Plant Sciences》 2014年第26期3823-3828,共6页
In this study, the effects of a silicon (Si) application on the biomass, chlorophyll level and silicon level of sugarcane moderate pest resistance (RB72454) and susceptible (SP801842) cultivars were tested. Investigat... In this study, the effects of a silicon (Si) application on the biomass, chlorophyll level and silicon level of sugarcane moderate pest resistance (RB72454) and susceptible (SP801842) cultivars were tested. Investigations were also carried out to assess the effect of silicon on Diatraea saccharalis infestation. The experiments were conducted in a greenhouse using the treatments consisting moderate pest resistant and susceptible culivar, with or without silicon application. The silicon was applied to the soil around the plants. The experiment was laid in complete randomized design with 4 treatments and 10 replicates. The data were subjected to an analysis of variance, and the averages were compared using the Tukey test (p ≤ 0.05). Significant changes were observed in the fresh and dry masses of the aerial portions and the root system, as well as in the plant chlorophyll and silicon levels. The silicon content increased in the susceptible variety which was significantly equal for moderate resistance variety. Chlorophyll content increased in silicon treated cultivars. Sixty days after the last application, 10 adult D. saccharalis moths were released onto each pot. However, due to the low infestation, the effects of silicon on the insect incidence could not be determined. One can conclude that silicon is beneficial for the growth of the aerial portions of sugarcane and causes a significant increase in chlorophyll levels. 展开更多
关键词 INSECT Diatraea saccharalis Induced Resistance IPM
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Harmonia axyridis Pallas(Coleoptera:Coccinellidae):Biological aspects and thermal requirements
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作者 Tatiana de Oliveira Ramos Terezinha Monteiro dos Santos-Cividanes +1 位作者 Francisco Jorge Cividanes Lais da Conceicao dos Santos 《Advances in Entomology》 2014年第1期42-46,共5页
The aim of this study was to determine the biological aspects and thermal requirements of Harmonia axyridis Pallas (Coleoptera: Coccinellidae) fed daily with Anagasta kuehniella (Zeller) (Lep-idoptera: Pyralidae) eggs... The aim of this study was to determine the biological aspects and thermal requirements of Harmonia axyridis Pallas (Coleoptera: Coccinellidae) fed daily with Anagasta kuehniella (Zeller) (Lep-idoptera: Pyralidae) eggs. Under laboratory conditions, the experiment was carried out in acclimatized chambers set to 18°C, 21°C, 24°C, 27°C, and 30°C. Larvae of H. axyridis were separated, kept in a glass tube, and fed with A. kuehniella eggs. The Asiatic lady beetle adults were separated into 20 couples and kept in plastic cups receiving the same food as the larvae. The length of the larval, pupal, and total biological cycle (from egg to adult) stages declined significantly from 18°C to 27°C, but was stable between 27°C and 30°C. Survival was similar for larvae from the first to the fourth stadium when kept at 18°C, 21°C, and 24°C with a higher total biological cycle survival at 27°C. H. axyridis males presented higher longevity at 18°C and 21°C in comparison to females that had a longer life and a higher fecundity at 24°C and 27°C, respectively. The lower thermal limit for biological cycle development was 12.4°C, and the thermal constant was 243.9 degree-days. 展开更多
关键词 Anagasta kuehniella Biological Control DEGREE-DAYS
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Weed Control Strips Influences on the Rubber Tree Growth
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作者 Caio Doria Guzzo Leonardo Bde Carvalho +2 位作者 Pedro Luis da CAAlves Elaine Cristine Piffer Goncalves Paulo FGiancotti 《American Journal of Plant Sciences》 2014年第8期1059-1068,共10页
Hevea brasiliensis (rubber tree) is the most widely cultivated tree species for producing natural rubber latex whose productivity can be reduced by weeds. Field experiment was carried out during two years to evaluate ... Hevea brasiliensis (rubber tree) is the most widely cultivated tree species for producing natural rubber latex whose productivity can be reduced by weeds. Field experiment was carried out during two years to evaluate the growth of rubber tree plants submitted to different weed control strips (0-weed-free, 50, 100, 150, 200, 250, 300, 350, and 400-(weedy cm) and to determine the critical width of weed control strip during the establishment of rubber tree plantation. Weed community was composed mainly by Urochloa decumbens (90%). The width of the weed control strip influenced on the initial plant growth of rubber trees, reducing the plant height, stem diameter, leaf area, and aboveground dry mass accumulation. In consequence, crop plantation was affected by the width of weed control. The critical width of the weed control strip for establishment of a rubber tree plantation was within 100 cm. 展开更多
关键词 Hevea brasiliensis Urochloa decumbens Weed Control Weed Interference
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Evaluation of growth performances of crossbreds and backcrossbreds with purebreds Nishikigoi and Hungarian carp(Cyprinus carpio)
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作者 Vander Bruno Santos Lucas Rosan Furquim 《Aquaculture and Fisheries》 2025年第3期452-458,共7页
This study aimed to evaluate growth curves among different common carp genotypes,according to fingerling performance and morphometry.Fingerlings selected according to Nishikigoi pattern,either(9.66±1.47)cm in sta... This study aimed to evaluate growth curves among different common carp genotypes,according to fingerling performance and morphometry.Fingerlings selected according to Nishikigoi pattern,either(9.66±1.47)cm in standard length,from crossbred and pure carp,respectively,were cultivated in 8 cages(4 replicates for each genotype),measuring 9 m(3.0 m×2.0 m×1.5 m)each,in a 1500 m^(2)(12 m×125 m)pond at a depth of 1.60 m with 10 fingerlings/m^(3).Fish were fed four times a day at the rate of 5%-7% of biomass with the same specific diet for each growth stage.Forty carp of each genotype(10 fish/cage)were weighed at days 0,60,150,270 and 330 of cultivation.They were weighed and measured for head length,standard length,body height and body width.The Gompertz model was fit for weight×age data for comparison of absolute and relative growth rate,weight and age at the inflection points.The crossbred genotype showed better survival,weight gain and feed conversion compared to pure carp(P<0.05).The final weight estimate at 330 days was 38.45% higher in the crossbred genotype(289.16 g)when compared to the pure carp(208.85 g).The pure genotype presented lower weight(431.60 g),age(559.71 days)and absolute growth rate(1.03 g/day)at the inflection points when compared to the crossbred genotype(587.69 g;559.71 days and 1.46 g/day,respectively).Body morphometric relationships changed with fish growth,and this occurred differently,depending on carp genotype evaluated.From these results,it can be concluded that crossing Nishikigoi with Hungarian carp can be a strategy to improve desirablecharacteristicsinkoi. 展开更多
关键词 Body conformation CROSSING GOMPERTZ Growth rate
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