An inventory of Rhynchophorus species was carried out to determine their diversity, biogeographical variability and morphometrics. A shotgun trapping method was used at nine sites in three districts over a four-month ...An inventory of Rhynchophorus species was carried out to determine their diversity, biogeographical variability and morphometrics. A shotgun trapping method was used at nine sites in three districts over a four-month period, identifying three species: R. quadrangulus, R. phoenicis, R. ferrugineus and a probable variant of R. phoenicis. Of these species, R. phoenicis stands out as the most widespread palm weevil, while the probable variant of R. phoenicis is considered the rarest subspecies in the Maniema region. The color of the head and elytra is a criterion for distinguishing the different species of Rhynchophorus spp. Morphological criteria indicate that the probable subspecies of R. phoenicis is the largest palm weevil in the Maniema region and even globally. It is followed by R. quadrangulus and, by far, by R. phoenicis. The smallest palm weevil in Maniema is R. ferrugineus. Moreover, these criteria reveal that, for all three species identified, the female is generally larger than the male. This study has the merit of extending the distribution of R. ferrugineus from the Maghreb to the central East of the DRC, and highlighting a subspecies of R. phoenicis. Recognition of the sexes on the basis of the shape of the tip of the abdomen (oval in the male and flat in the female) is an additional contribution.展开更多
Smart precision agriculture utilizes modern information and wireless communication technologies to achieve challenging agricultural processes.Therefore,Internet of Things(IoT)technology can be applied to monitor and d...Smart precision agriculture utilizes modern information and wireless communication technologies to achieve challenging agricultural processes.Therefore,Internet of Things(IoT)technology can be applied to monitor and detect harmful insect pests such as red palm weevils(RPWs)in the farms of date palm trees.In this paper,we propose a new IoT-based framework for early sound detection of RPWs using fine-tuned transfer learning classifier,namely InceptionResNet-V2.The sound sensors,namely TreeVibes devices are carefully mounted on each palm trunk to setup wireless sensor networks in the farm.Palm trees are labeled based on the sensor node number to identify the infested cases.Then,the acquired audio signals are sent to a cloud server for further on-line analysis by our fine-tuned deep transfer learning model,i.e.,InceptionResNet-V2.The proposed infestation classifier has been successfully validated on the public TreeVibes database.It includes total short recordings of 1754 samples,such that the clean and infested signals are 1754 and 731 samples,respectively.Compared to other deep learning models in the literature,our proposed InceptionResNet-V2 classifier achieved the best performance on the public database of TreeVibes audio recordings.The resulted classification accuracy score was 97.18%.Using 10-fold cross validation,the fine-tuned InceptionResNet-V2 achieved the best average accuracy score and standard deviation of 94.53%and±1.69,respectively.Applying the proposed intelligent IoT-aided detection system of RPWs in date palm farms is the main prospect of this research work.展开更多
The rice water weevil （RWW） Lissorhoptrus oryzophilus Kuschel （Coleoptera： Curculionidae） is an invasive insect pest office Oryza sativa L. in China. Little is known about the interactions of this weevil with ind...The rice water weevil （RWW） Lissorhoptrus oryzophilus Kuschel （Coleoptera： Curculionidae） is an invasive insect pest office Oryza sativa L. in China. Little is known about the interactions of this weevil with indigenous herbivores. In the present study, adult feeding and population density of the weevil, injury level of striped stem borer Chilo suppressalis （Walker） （Lepidoptera： Pyralidae） and pink stem borer Sesamia inferens （Walker） （Lepidoptera： Noctuidae） to flee, as well as growth status of their host plants were surveyed in a rice field located in Southeastern Zhejiang, China, in 2004 with the objective to discover interspecific interactions on the flee. At tillefing stage, both adult feeding of the weevil and injury of the stem borers tended to occur on larger tillers （bearing 5 leaves） compared with small tillers （bearing 2-4 leaves）, but the insects showed no evident competition with each other. At booting stage, the stem borers caused more withering/dead hearts and the weevil reached a higher density on the plants which had more productive tillers and larger root system; the number of weevils per tiller correlated negatively with the percentage of withering/dead hearts of plants in a hill. These observations indicate that interspecific interactions exist between the rice water weevil and the rice stem borers with negative relations occurring at booting or earlier developmental stages of rice.展开更多
The Central Bank of Nigeria Anchored Borrowers Programme efforts geared towards massive production of cowpea and sustainable food security is challenged with post-harvest losses especially due to insect pest infestati...The Central Bank of Nigeria Anchored Borrowers Programme efforts geared towards massive production of cowpea and sustainable food security is challenged with post-harvest losses especially due to insect pest infestation in storage. So also, chemical method of pest control posed more health and ecological challenges than food insecurity. This work investigated the effect of Piper guineense on cowpea storage weevil at the agronomy laboratory of the Lagos State Polytechnic, Ikorodu. Contact toxicity of P. guineense at 0.2, 0.4, 0.6, 0.8 and 1 g per 20 g of cowpea seeds in test tubes including a control was observed. The treatment materials exhibited significant efficacy from 24 hours after infestation. P. guineense at 1 g concentration significantly reduced the oviposition potential, egg hatching rate, holes and emergence of adult Callosobruchus maculatus on treated seeds. The powders caused chronic toxicity and inhibit development. All the responses were found to be concentration dependent. Increasing rates of P. guineense increased performance. The implication of these results is discussed and recommendations proffered.展开更多
World Food Programme boosts rice productivity in West Africa with Chinese know-how In Bananko,a village in Guinea,LancinéCamara used to worry about the conservation of crops.The villagers store their harvest in b...World Food Programme boosts rice productivity in West Africa with Chinese know-how In Bananko,a village in Guinea,LancinéCamara used to worry about the conservation of crops.The villagers store their harvest in bags or granaries covered with straw.Crops stored in these ways easily became rotten or were attacked by termites,rodents and weevils.In such storage conditions,even seeds were not secure.展开更多
Increasing concern over the amount of insecticide residues in food has encouraged research for ecologically sound strategies to effectively manage stored-product insect pests and protect living organisms and the envir...Increasing concern over the amount of insecticide residues in food has encouraged research for ecologically sound strategies to effectively manage stored-product insect pests and protect living organisms and the environment. Botanicals were evaluated as potential alternatives to control maize weevil, Sitophilus zeamais Motschulsky, in stored sorghum, Sorghum bicolor (L.) Moench. Beetles and moths of stored grain at farm and consumer levels damage 5 - 35% worldwide and >40% in tropical countries. Maize weevil is the most damaging storage insect of sorghum grain. Management of storage insects relies on insecticides that leave residues in food and the environment. Treatments were powders of neem bark, Azadirachta indica;mesquite pods, Prosopis glandulosa;milkweed leaves, Asclepias speciosa;and a check (no botanical powder). Eight newly emerged maize weevils were provided 5 g of Malisor-84 grain treated with three doses of each plant powder. Every 2 days, data were recorded on the number of adults killed by each treatment. Percentage killed was calculated by dose per treatment and compared with the check. Grain loss was calculated based on initial and final weights. LD50 was determined by probit analysis, and associations between variables were assessed by simple linear correlation. Powder of mesquite and milkweed at 0.2 g were more effective than neem or the check in killing S. zeamais (>90%) and reducing grain damage (34 - 35.2%) and weight loss (0.8%). Milkweed at 0.1 g and neem at 0.2 g killed 78.1% of weevils. Neem at 0.05 g was slow acting, resulting in 62.5% dead and more grain damage (59.5%) and weight loss (3.6%). Botanicals at low doses (LD50 = 0.2 - 0.4 g) showed efficacy in controlling maize weevils and are recommended alternatives to guarantee quantity and quality of stored cereal grains.展开更多
Chak-hao,the Forbidden Rice from Manipur,India,is an aromatic,purplish-black rice variety that has been awarded a geographical indication tag to preserve and promote its traditional cultivation in Manipur,India.Althou...Chak-hao,the Forbidden Rice from Manipur,India,is an aromatic,purplish-black rice variety that has been awarded a geographical indication tag to preserve and promote its traditional cultivation in Manipur,India.Although Chak-hao is a hardy landrace with field tolerance to biotic stress,its grains are highly susceptible to storage pest infestations,particularly those caused by the rice weevil(Sitophilus oryzae).This severely compromises its commercial storage quality,as pest damage reduces both nutritional value and quantity.展开更多
The reproductive potential of overwintering boll weevil, Anthonomus grandis grandis （Boheman）, females collected from pheromone traps in September, November and January, fed for 1, 3, and 5 weeks on plant pollens, a...The reproductive potential of overwintering boll weevil, Anthonomus grandis grandis （Boheman）, females collected from pheromone traps in September, November and January, fed for 1, 3, and 5 weeks on plant pollens, and then provided cotton squares, was determined in the laboratory at 27 ~ I^C, 65% RH, and a photoperiod 13 ： 11 （L ： D） h. Duration of pollen feeding by overwintering boll weevils did not significantly influence egg and feeding punctures, or puncture ratios （egg to total punctures） for any of the three months of parent weevil collections when provided cotton squares on a daily basis. However, punctures and puncture ratios are significantly different when comparing mean data between months of boll weevil collections. When boll weevils were provided with cotton squares daily, the pre-ovipositional periods of female parents captured in September, November and January were 5, 9 and 14 days, respectively. The rate of eggs by females was significantly lower during November and January than September. Female parents collected in September produced a significantly higher percentage of eggs yielding adult progeny than those collected in November and January. Life table parameters indicated that net reproductive rate （Ro） of boll weevil females collected in September was 1.2- fold higher than those collected in November and 10.7-fold higher than those collected in January. Except for testes size, no differences in male reproductive parameters were observed during the cotton-free period compared with males captured during mid-cotton （June）. The number of oocytes in the ovarioles and the number of ooeytes containing yolk were significantly lower during September, November and January compared with June. The reproductive potential ofoverwintering boll weevil females collected in different months is an important consideration in determining the success of any control strategy.展开更多
Manglietia ventii is a highly endangered plant species endemic to Yunnan province in China, where there are only five known small populations. Despite abundant flowering there is very low fruit and seed set,and very f...Manglietia ventii is a highly endangered plant species endemic to Yunnan province in China, where there are only five known small populations. Despite abundant flowering there is very low fruit and seed set,and very few seedlings in natural populations, indicating problems with reproduction. The causes of low fecundity in M. ventii are not known, largely because of insufficient knowledge of the species pollination ecology and breeding system. We conducted observations and pollination experiments, and analyzed floral scents to understand the pollinatoreplant interactions and the role of floral scent in this relationship, as well as the species breeding system. Like the majority of Magnoliaceae, M. ventii has protogynous and nocturnal flowers that emit a strong fragrance over two consecutive evenings. There is a closing period(the pre-staminate stage) during the process of anthesis of a flower, and we characterize the key flowering process as an "open-close-reopen" flowering rhythm with five distinct floral stages observed throughout the floral period of this species: pre-pistillate, pistillate, pre-staminate, staminate,and post-staminate. Flowers are in the pistillate stage during the first night of anthesis and enter the staminate stage the next night. During anthesis, floral scent emission occurs in the pistillate and staminate stages. The effective pollinators were weevils(Sitophilus sp.) and beetles(Anomala sp.), while the role of Rove beetles(Aleochara sp.) and thrips(Thrips sp.) in pollination of M. ventii appears to be minor or absent. The major chemical compounds of the floral scents were Limonene, b-Pinene, a-Pinene, 1,8-Cineole, Methyl-2-methylbutyrate, p-Cymene, Methyl-3-methyl-2-butenoate and 2-Methoxy-2-methyl-3-buten, and the relative proportions of these compounds varied between the pistillate and staminate stages. Production of these chemicals coincided with flower visitation by weevils and beetles.The results of pollination experiments suggest that M. ventii is pollinator-dependent, and low seed set in natural populations is a result of insufficient pollen deposition. Thus, conservation of the species should focus on improving pollination service through the introduction of genetically variable individuals and increase in density of reproducing trees.展开更多
Seed hoarders show different hoarding and eating responses towards insect-infested seeds that can affect the fitness of both the seeds and insects. It remains unclear how seed hoarders adopt different strategies in ea...Seed hoarders show different hoarding and eating responses towards insect-infested seeds that can affect the fitness of both the seeds and insects. It remains unclear how seed hoarders adopt different strategies in eating and hoarding infested seeds with and without larvae concealed inside. Here we investigated hoarding and eating responses of Edward＇s long-tailed rats Leo- poldamys edwardsi （scatter hoarders） to weevil infestation of cork oak Quercus variabilis seeds within outdoor enclosures. We provided sound seeds, larvae-emerged seeds, （infested seeds where larvae have emerged） and larvae-concealed seeds （infested seeds with larvae concealed inside） to subjects independently （each seed type presented separately） and in pairwise combina- tions （sound and larvae-emerged seeds; sound and larvae-concealed seeds）. We found that L. edwardsi removed, scatter hoarded and ate fewer larvae-emerged seeds than sound seeds. No difference was found between sound seeds and larvae-concealed seeds. These results suggest that sound and larvae-concealed seeds are more favored by L. edwardsi than larvae-emerged seeds. We posit that not only plants but also insects may benefit from the behavioral responses of hoarders to seed infestation under natural conditions展开更多
Samples of pheromone lures used in boll weevil, Anthonomus grandis （Boheman）, eradication programs are routinely analyzed by Gas Chromatography （GC） to ensure lures are adequately dosed with grandlure, the synthet...Samples of pheromone lures used in boll weevil, Anthonomus grandis （Boheman）, eradication programs are routinely analyzed by Gas Chromatography （GC） to ensure lures are adequately dosed with grandlure, the synthetic aggregation phero- mone produced by male weevils. However, preparation of GC samples is tedious, time consuming, and requires a moderate level of experience. We examined the use of a commercially-available electronic nose （e-nose） for rapidly assessing the grandlure contents of lures. The e-nose was trained to recognize headspace collections of grandlure emitted from new lures and after lures were aged under field conditions for 4 d, 7 d, 10 d, and 14 d. Based on cross-validation of the training set, the e-nose was 82% accurate in discriminating among the different age classes of lures. Upon sampling headspace collections of pheromone from a different set of field-aged lures, the e-nose was 〈50% accurate in discriminating 4 d, 7 d, and 10 d aged lures from the other age classes of lures. However, the e-nose identified new and 14 d aged lure samples with 100% accuracy. In light of these findings, e-nose technology shows considerable promise as an alternative approach for rapidly assessing the initial grandlure contents of lures used in boll weevil eradication programs.展开更多
Objetive: To explore the potential insecticidal, ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora(Syn. Cassia tora) against cowpea weevil(Callosobruchus maculatus).Metho...Objetive: To explore the potential insecticidal, ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora(Syn. Cassia tora) against cowpea weevil(Callosobruchus maculatus).Method: The activities were evaluated using standard protocols.In these bioassays, the cowpea seeds were used directly as an insect feed. The activity of the extract and isolated compounds were tested at concentrations of 100, 200 and 300 μg/mL and compared to neem oil and cinnamaldehyde(as standard positive controls). Phytochemical analysis of the ethyl acetate extract was done through a number of chromatographic techniques and the structures of the isolated compounds were established through comprehensive spectroscopic analysis including 2 D-NMR and ESI-MS studies.Results: Fractionation of the active ethyl acetate extract resulted in the isolation of one known anthraquinone,aurantio-obtusin(1) and a novel compound that was named as cassiatorin(2). Compounds1 and 2 showed comparable insect antifeedant properties with the positive controls while their insecticidal and ovipositor deterrent effects were far superior to the standard controls.Conclusions: It is thus concluded that Senna tora extracts and the isolated compounds(1 and2) may be employed in the postharvest management of stored cowpea seeds and as other crop protectants.展开更多
Callosobruchus maculatus(Fabricius,1775)(Coleoptera:Bruchinae)is a destructive agricultural pest that is harmful to beans worldwide and an important quarantine pest in China.It was divided into two phenotypes based on...Callosobruchus maculatus(Fabricius,1775)(Coleoptera:Bruchinae)is a destructive agricultural pest that is harmful to beans worldwide and an important quarantine pest in China.It was divided into two phenotypes based on polyphenism:normal and flight forms.In this study,we first compared the morphological structures of the compound eyes of the two forms.According to the results of scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(micro-CT),and computer three-dimensional reconstruction,there are no differences in the structures of the compound eyes between the normal and flight forms except for the number of ommatidia.From the internal structure,the compound eyes have a biconvex cornea with open rhabdom and acone eye,crystalline cone directly connected with rhabdom,and no clear zone.It is a kind of apposition eye.Ommatidia facets range in shape from quadrilateral to hexagonal and some irregular shapes.On electroretinograms(ERGs),the normal and flight forms showed different spectral sensitivities:the normal form had the strongest response to ultraviolet light,whereas the flight form had the strongest response to white light.Behavioral assays revealed that the normal and flight forms showed completely opposite phototaxis behaviors;the flight form exhibited positive phototaxis,whereas the normal form exhibited negative phototaxis.This study not only enriches our knowledge on coleopteran compound eyes but also provides a foundation for in-depth research on the photoreceptor mechanisms of compound eyes,which may be useful in pest control management.展开更多
Genetic comparison between Rhynchophorus ferrugineus （Coleoptera： Curculionidae： Rhynchophorinae） and other four Rhynchophorus spp. such as R. bilineatus, R. phoenicis, R. cruentatus and R. palmarum was investigat...Genetic comparison between Rhynchophorus ferrugineus （Coleoptera： Curculionidae： Rhynchophorinae） and other four Rhynchophorus spp. such as R. bilineatus, R. phoenicis, R. cruentatus and R. palmarum was investigated using partial sequences of Cytochrome c oxidase subunit I （COl） mitochondrial gene. The number ofpolymorphic sites ranged from 79 to 102 while the genetic distances ranged from 0.058 to 0.095. The number of polymorphic sites, genetic distances and phylogenetic relationships among R. ferrugineus and the other four tested species revealed that R.ferrugineus was more closely related to R. bilineatus while it was distantly related to R. palmarum. It is possible to rank the five tested species as follows： R.ferrugineus, R. bilineatus, R. phoenicis, R. cruentatus and R. palmarum. The result of this study is the first step of the revision of the uncertain taxonomic status and phylogenetic relationships among the Rhynchophorus genus. Further analysis should be performed using other Rhynchophorus species as well as other molecular markers.展开更多
The Kingdom of Saudi Arabia is one of the leading date producing countries. Unfortunately, this important fruit crop is under great threat from the red palm weevil （RPW） （Rhynchophorus ferrugineus）, which is a hig...The Kingdom of Saudi Arabia is one of the leading date producing countries. Unfortunately, this important fruit crop is under great threat from the red palm weevil （RPW） （Rhynchophorus ferrugineus）, which is a highly invasive pest. Several techniques, including visual inspection, acoustic sensors, sniffer dogs, and pheromone traps have been tried to detect the early stages of a RPW infestation; however, each method has suffered certain logistical and implementation issues. We have applied laser induced breakdown spectroscopy （LIBS） for the early detection of RPW infestation. Through the analysis of the observed LIBS spectra of different infested and healthy samples, we have found presence of Ca, Mg, Na, C, K elements and OH, CN molecules. The spectra also reveal that with the population growth of the pest, the intensity of Mg and Ca atomic lines in LIBS spectra increases rapidly. Similar behavior is observed in the molecular lines of LIBS spectra. The obtained results indicate that the LIBS technique can be used for the early detection of RPW infestation without damaging the date palms.展开更多
The red palm weevil （RPW） Rhynchophorusferrugineus is one of the most invasive insect pests causing massive damage on date palms over the world. Synthetic pyrethroid insecticide beta-cyfluthrin has been evaluated ag...The red palm weevil （RPW） Rhynchophorusferrugineus is one of the most invasive insect pests causing massive damage on date palms over the world. Synthetic pyrethroid insecticide beta-cyfluthrin has been evaluated against developmental stages of RPW under laboratory conditions. These stages were exposed to residual film of the insecticide on transparent cups using a Potter precision laboratory spray tower. Percent mortality of males and females were recorded 0.5, 2.0 and 24 h after treatment. Furthermore, date palm offshoots were infested in mesh house, two months later, offshoots treated with 300 ppm （p.g/mL） beta-eyfluthrin using two methods dipping and injection. Bioassay test showed beta-cyfluthrin at 300 ppm caused 86,7% and 93,3% mortality against males and females after 2 h respectively with LC50 135.74 and 109.4 ppm. By increasing the concentration at 400 ppm, mortality reached 100% against males and females after 24 h, Developmental stages, eggs and larvae were more sensitive toward the insecticide, where at 120 ppm no eggs hatched after 96 h and 86.7% mortality was recorded at 200 ppm against larvae after 30 rain with LC50 93.19 ppm. In addition, dipping method of date palm offshoots in 300 ppm beta-cyfluthrin was a very convenient way to control all RPW stages compared to injection method. So, it possible to recommend this method for treating the date palm offshoots in such insecticide as one of the most important elements of integrated pest management for standardizing insecticide based quarantine protocols.展开更多
The Red Palm Weevil （RPW）, Rhynchophorus ferrugineus （Olivier）, （Coleoptera, Curculionidae, Rhynchophorinae）, is an invasive species that is originated from Southeast Asia. It has invaded Middle East, several co...The Red Palm Weevil （RPW）, Rhynchophorus ferrugineus （Olivier）, （Coleoptera, Curculionidae, Rhynchophorinae）, is an invasive species that is originated from Southeast Asia. It has invaded Middle East, several countries of the Mediterranean Basin, Caribbean （Island of Curacao, Netherland Antilles）, Lebanon and United States of America （Laguna Beach, Orange County, California） during the last three decades where it attacks palm trees. This study investigated the geographical variation among geographic populations of RPW collected from twelve invaded countries using cytochrome b （Cytb） and ITS2 partial sequences. The comparison among the Cytb sequences resulted in three different haplotypes designated as HB 1 to HB3. The three haplotypes were subdivided into two phylogenetic groups according to their geographic positions： （1） the ＂Multi-Continent＂ group containing HB 1 haplotype detected in eight populations belonging to three different Continents such as Africa-Egypt, Asia-Kingdom of Saudi Arabia and Turkey and Europe-Spain, Italy, Greece, Cyprus and France, and （2） the ＂Asian＂ group includes four populations from Iran （harboring HB2 haplotype）, Pakistan, UAE, and Oman （harboring HB3 haplotype）. This mitochondrial pattern of genetic diversity suggests that the tested RPW populations subdivided genetically into different sub-populations under the influence of genetic drift. According to these results we concluded that the twelve studied RPW populations are originating from different source populations in the RPW area of origin.展开更多
The Red Palm Weevil （RPW）, Rhynchophorus ferrugineus （Olivier）, （Coleoptera, Curculionidae, Rhynchophorinae）, is an invasive species that is originated from Southeast Asia. It has.invaded Middle East and several...The Red Palm Weevil （RPW）, Rhynchophorus ferrugineus （Olivier）, （Coleoptera, Curculionidae, Rhynchophorinae）, is an invasive species that is originated from Southeast Asia. It has.invaded Middle East and several countries of the Mediterranean Basin during the last three decades where it attacks palm trees. During the last three decades, multiple introductions of RPW to the Middle East, Europe and Caribbean （Island of Curacao, Netherland Antilles）, Lebanon and United States of America （Laguna Beach, Orange County, California） （USA） have occurred and the RPW is now a serious pest of many palm species. Duration of all life parameters varies significantly where the entire life cycle takes about 45 to 298 days. Different artificial diets were developed and were tested for mass rearing of RPW. Control of RPW is difficult due to the concealed nature of the life cycle of the pest. Integrated Pest Management （IPM） strategy has been applied successfully to deal with RPW problem. The IPM strategy consists of various preventive and curative methods; those methods were categorized in nine categories in this review. The main objective of this work was to review the existing knowledge on RPW＇s different aspects, with an ultimate aim of revealing the actual situation of the research on RPW.展开更多
Knowing the developmental states of stored grain insects, especially for the immature stages hidden in cereal kernel, such as Sitophilus zeamais, could be in favor of monitoring early and controlling effectively. Atla...Knowing the developmental states of stored grain insects, especially for the immature stages hidden in cereal kernel, such as Sitophilus zeamais, could be in favor of monitoring early and controlling effectively. Atlas and scale parameters on different developmental stages of S. zeamais in wheat kernel were captured and described by three-dimensional microscope of super depth of field observation. The four instars of larva, pre-pupa, pupa, new adult, old adult in kernel could be seen by dissecting the infested kernels. The length, height, and width of larva body increased with insect development and centralized the sizes corresponding to the four instars of larva. The length of larva body centralized near 554, 746, 1 462, and 2 147 μm. The height of larva body centralized about 388, 575, 847, and 1 651 μm. The width of larva body centralized near 340, 598, 798, and 1 568 μm. Head capsule width was in same size for each exuviating period, centralized near 203, 317, 535, and 603 μm, and got big sharply with the instar changed. Developmental duration of four larva instars was about 21 days reared in wheat, less than 28 days reared in maize as published. The atlas and description should be helpful for monitoring the S. zeamais development hidden in cereal kernels and designing control strategy.展开更多
Plant diseases generate challenging problems in commercial, agriculture and pose real economic threats to both conventional and organic farming systems. The red palm weevil (Rhynchophorus ferrugineus) (RPW) is one of ...Plant diseases generate challenging problems in commercial, agriculture and pose real economic threats to both conventional and organic farming systems. The red palm weevil (Rhynchophorus ferrugineus) (RPW) is one of the most destructive pests of palms in the world. Nowadays, control methods revolve around treatments based on chemicals, biotechnological systems using semi-chemicals or the development of the sterile insect technique (hardly sustainable at this time) and biological control. Biological control as the use of natural microorganisms, extracted products from microorganisms or genetically improved to resist or eliminate of pathogens. Our aim was to evaluate the entomopathogenicity of indigenous Beauveria bassiana and Metarhizium anisopliae obtained in Gaza strip against larvae and adults of R. ferrugineus in order to identify indigenous strains potentially suitable for Red Palm Weevil biological control. B. bassiana & M. anisopliae were isolated from larvae and adult dead of RPW from different position of Gaza strip. Morphological analysis of the isolated fungi and molecular identification was determined using PCR technique. Also, the efficiency of the isolated fungi were evaluated under lab conditions and optimized as a biological agent. On the anther hand, the ability of treated RPW male to infect females is examined and calculated using Abbott's formula. Our results showed that the B. bassiana and M. anisopliae exhibited a good biological control agent against larvae and adults of RPW. The pathogenicity of the two most virulent isolates and the toxicity assay on larvae showed a highest mortality percentage nearly to 100% by 6 days after spraying the larvae with 3.4 × 108 spores/ml of B. bassiana. The mortality percentage reaches to 90% after spraying the larvae with 3.6 × 108 spores/ml of M. anisopliae. The mortality for the adults treated with pesticide arrives to 50% and the control group 10% at the same time. The results revealed that the infection of the adult males by Entomopathogenic fungi (EPF) can be disseminated into the healthy population, after RPW treatment with B. bassiana and M. anisopliae. Our research concludes that B. bassiana and M. anisopliae locally isolated can be used as biological very effective.展开更多
文摘An inventory of Rhynchophorus species was carried out to determine their diversity, biogeographical variability and morphometrics. A shotgun trapping method was used at nine sites in three districts over a four-month period, identifying three species: R. quadrangulus, R. phoenicis, R. ferrugineus and a probable variant of R. phoenicis. Of these species, R. phoenicis stands out as the most widespread palm weevil, while the probable variant of R. phoenicis is considered the rarest subspecies in the Maniema region. The color of the head and elytra is a criterion for distinguishing the different species of Rhynchophorus spp. Morphological criteria indicate that the probable subspecies of R. phoenicis is the largest palm weevil in the Maniema region and even globally. It is followed by R. quadrangulus and, by far, by R. phoenicis. The smallest palm weevil in Maniema is R. ferrugineus. Moreover, these criteria reveal that, for all three species identified, the female is generally larger than the male. This study has the merit of extending the distribution of R. ferrugineus from the Maghreb to the central East of the DRC, and highlighting a subspecies of R. phoenicis. Recognition of the sexes on the basis of the shape of the tip of the abdomen (oval in the male and flat in the female) is an additional contribution.
基金This research received the support from the Deputyship for Research&Innovation,Ministry of Education in Saudi Arabia through the project number(UB-26-1442).
文摘Smart precision agriculture utilizes modern information and wireless communication technologies to achieve challenging agricultural processes.Therefore,Internet of Things(IoT)technology can be applied to monitor and detect harmful insect pests such as red palm weevils(RPWs)in the farms of date palm trees.In this paper,we propose a new IoT-based framework for early sound detection of RPWs using fine-tuned transfer learning classifier,namely InceptionResNet-V2.The sound sensors,namely TreeVibes devices are carefully mounted on each palm trunk to setup wireless sensor networks in the farm.Palm trees are labeled based on the sensor node number to identify the infested cases.Then,the acquired audio signals are sent to a cloud server for further on-line analysis by our fine-tuned deep transfer learning model,i.e.,InceptionResNet-V2.The proposed infestation classifier has been successfully validated on the public TreeVibes database.It includes total short recordings of 1754 samples,such that the clean and infested signals are 1754 and 731 samples,respectively.Compared to other deep learning models in the literature,our proposed InceptionResNet-V2 classifier achieved the best performance on the public database of TreeVibes audio recordings.The resulted classification accuracy score was 97.18%.Using 10-fold cross validation,the fine-tuned InceptionResNet-V2 achieved the best average accuracy score and standard deviation of 94.53%and±1.69,respectively.Applying the proposed intelligent IoT-aided detection system of RPWs in date palm farms is the main prospect of this research work.
基金Project (No. 2002CB111403) supported by the National Basic Re-search and Development Program (973) of China
文摘The rice water weevil （RWW） Lissorhoptrus oryzophilus Kuschel （Coleoptera： Curculionidae） is an invasive insect pest office Oryza sativa L. in China. Little is known about the interactions of this weevil with indigenous herbivores. In the present study, adult feeding and population density of the weevil, injury level of striped stem borer Chilo suppressalis （Walker） （Lepidoptera： Pyralidae） and pink stem borer Sesamia inferens （Walker） （Lepidoptera： Noctuidae） to flee, as well as growth status of their host plants were surveyed in a rice field located in Southeastern Zhejiang, China, in 2004 with the objective to discover interspecific interactions on the flee. At tillefing stage, both adult feeding of the weevil and injury of the stem borers tended to occur on larger tillers （bearing 5 leaves） compared with small tillers （bearing 2-4 leaves）, but the insects showed no evident competition with each other. At booting stage, the stem borers caused more withering/dead hearts and the weevil reached a higher density on the plants which had more productive tillers and larger root system; the number of weevils per tiller correlated negatively with the percentage of withering/dead hearts of plants in a hill. These observations indicate that interspecific interactions exist between the rice water weevil and the rice stem borers with negative relations occurring at booting or earlier developmental stages of rice.
文摘The Central Bank of Nigeria Anchored Borrowers Programme efforts geared towards massive production of cowpea and sustainable food security is challenged with post-harvest losses especially due to insect pest infestation in storage. So also, chemical method of pest control posed more health and ecological challenges than food insecurity. This work investigated the effect of Piper guineense on cowpea storage weevil at the agronomy laboratory of the Lagos State Polytechnic, Ikorodu. Contact toxicity of P. guineense at 0.2, 0.4, 0.6, 0.8 and 1 g per 20 g of cowpea seeds in test tubes including a control was observed. The treatment materials exhibited significant efficacy from 24 hours after infestation. P. guineense at 1 g concentration significantly reduced the oviposition potential, egg hatching rate, holes and emergence of adult Callosobruchus maculatus on treated seeds. The powders caused chronic toxicity and inhibit development. All the responses were found to be concentration dependent. Increasing rates of P. guineense increased performance. The implication of these results is discussed and recommendations proffered.
文摘World Food Programme boosts rice productivity in West Africa with Chinese know-how In Bananko,a village in Guinea,LancinéCamara used to worry about the conservation of crops.The villagers store their harvest in bags or granaries covered with straw.Crops stored in these ways easily became rotten or were attacked by termites,rodents and weevils.In such storage conditions,even seeds were not secure.
文摘Increasing concern over the amount of insecticide residues in food has encouraged research for ecologically sound strategies to effectively manage stored-product insect pests and protect living organisms and the environment. Botanicals were evaluated as potential alternatives to control maize weevil, Sitophilus zeamais Motschulsky, in stored sorghum, Sorghum bicolor (L.) Moench. Beetles and moths of stored grain at farm and consumer levels damage 5 - 35% worldwide and >40% in tropical countries. Maize weevil is the most damaging storage insect of sorghum grain. Management of storage insects relies on insecticides that leave residues in food and the environment. Treatments were powders of neem bark, Azadirachta indica;mesquite pods, Prosopis glandulosa;milkweed leaves, Asclepias speciosa;and a check (no botanical powder). Eight newly emerged maize weevils were provided 5 g of Malisor-84 grain treated with three doses of each plant powder. Every 2 days, data were recorded on the number of adults killed by each treatment. Percentage killed was calculated by dose per treatment and compared with the check. Grain loss was calculated based on initial and final weights. LD50 was determined by probit analysis, and associations between variables were assessed by simple linear correlation. Powder of mesquite and milkweed at 0.2 g were more effective than neem or the check in killing S. zeamais (>90%) and reducing grain damage (34 - 35.2%) and weight loss (0.8%). Milkweed at 0.1 g and neem at 0.2 g killed 78.1% of weevils. Neem at 0.05 g was slow acting, resulting in 62.5% dead and more grain damage (59.5%) and weight loss (3.6%). Botanicals at low doses (LD50 = 0.2 - 0.4 g) showed efficacy in controlling maize weevils and are recommended alternatives to guarantee quantity and quality of stored cereal grains.
文摘Chak-hao,the Forbidden Rice from Manipur,India,is an aromatic,purplish-black rice variety that has been awarded a geographical indication tag to preserve and promote its traditional cultivation in Manipur,India.Although Chak-hao is a hardy landrace with field tolerance to biotic stress,its grains are highly susceptible to storage pest infestations,particularly those caused by the rice weevil(Sitophilus oryzae).This severely compromises its commercial storage quality,as pest damage reduces both nutritional value and quantity.
文摘The reproductive potential of overwintering boll weevil, Anthonomus grandis grandis （Boheman）, females collected from pheromone traps in September, November and January, fed for 1, 3, and 5 weeks on plant pollens, and then provided cotton squares, was determined in the laboratory at 27 ~ I^C, 65% RH, and a photoperiod 13 ： 11 （L ： D） h. Duration of pollen feeding by overwintering boll weevils did not significantly influence egg and feeding punctures, or puncture ratios （egg to total punctures） for any of the three months of parent weevil collections when provided cotton squares on a daily basis. However, punctures and puncture ratios are significantly different when comparing mean data between months of boll weevil collections. When boll weevils were provided with cotton squares daily, the pre-ovipositional periods of female parents captured in September, November and January were 5, 9 and 14 days, respectively. The rate of eggs by females was significantly lower during November and January than September. Female parents collected in September produced a significantly higher percentage of eggs yielding adult progeny than those collected in November and January. Life table parameters indicated that net reproductive rate （Ro） of boll weevil females collected in September was 1.2- fold higher than those collected in November and 10.7-fold higher than those collected in January. Except for testes size, no differences in male reproductive parameters were observed during the cotton-free period compared with males captured during mid-cotton （June）. The number of oocytes in the ovarioles and the number of ooeytes containing yolk were significantly lower during September, November and January compared with June. The reproductive potential ofoverwintering boll weevil females collected in different months is an important consideration in determining the success of any control strategy.
基金Funding(No.U1302262)to W.B.Sun from the NSFC-Yunnan joint fund on key projectsSurvey and Germplasm Conservation of PSESP in Southwest China(2017e2020,2017FY100100)+1 种基金partly supported by the Young Academic and Technical Leader Raising Foundation of Yunnan Province(2015HB091)the Science and Technology Research Program of Kunming Institute of Botany,the Chinese Academy of Science(KIB2016005)to G.Chen
文摘Manglietia ventii is a highly endangered plant species endemic to Yunnan province in China, where there are only five known small populations. Despite abundant flowering there is very low fruit and seed set,and very few seedlings in natural populations, indicating problems with reproduction. The causes of low fecundity in M. ventii are not known, largely because of insufficient knowledge of the species pollination ecology and breeding system. We conducted observations and pollination experiments, and analyzed floral scents to understand the pollinatoreplant interactions and the role of floral scent in this relationship, as well as the species breeding system. Like the majority of Magnoliaceae, M. ventii has protogynous and nocturnal flowers that emit a strong fragrance over two consecutive evenings. There is a closing period(the pre-staminate stage) during the process of anthesis of a flower, and we characterize the key flowering process as an "open-close-reopen" flowering rhythm with five distinct floral stages observed throughout the floral period of this species: pre-pistillate, pistillate, pre-staminate, staminate,and post-staminate. Flowers are in the pistillate stage during the first night of anthesis and enter the staminate stage the next night. During anthesis, floral scent emission occurs in the pistillate and staminate stages. The effective pollinators were weevils(Sitophilus sp.) and beetles(Anomala sp.), while the role of Rove beetles(Aleochara sp.) and thrips(Thrips sp.) in pollination of M. ventii appears to be minor or absent. The major chemical compounds of the floral scents were Limonene, b-Pinene, a-Pinene, 1,8-Cineole, Methyl-2-methylbutyrate, p-Cymene, Methyl-3-methyl-2-butenoate and 2-Methoxy-2-methyl-3-buten, and the relative proportions of these compounds varied between the pistillate and staminate stages. Production of these chemicals coincided with flower visitation by weevils and beetles.The results of pollination experiments suggest that M. ventii is pollinator-dependent, and low seed set in natural populations is a result of insufficient pollen deposition. Thus, conservation of the species should focus on improving pollination service through the introduction of genetically variable individuals and increase in density of reproducing trees.
基金Acknowledgements We thank X Wang, Y Xiao, G Chen and D Huang for helps with trapping and seed collection. Z Zhang provided comments on an earlier version of this manuscript. We also thank the four anonymous reviewers for critical comments and suggestions. This study was partially funded by the Knowledge Innovation Program of the Chinese Academy of Science （KSCX2-SW-105, KSCX2-SW-103） and the National Natural Science Foundation of China （30800120）.
文摘Seed hoarders show different hoarding and eating responses towards insect-infested seeds that can affect the fitness of both the seeds and insects. It remains unclear how seed hoarders adopt different strategies in eating and hoarding infested seeds with and without larvae concealed inside. Here we investigated hoarding and eating responses of Edward＇s long-tailed rats Leo- poldamys edwardsi （scatter hoarders） to weevil infestation of cork oak Quercus variabilis seeds within outdoor enclosures. We provided sound seeds, larvae-emerged seeds, （infested seeds where larvae have emerged） and larvae-concealed seeds （infested seeds with larvae concealed inside） to subjects independently （each seed type presented separately） and in pairwise combina- tions （sound and larvae-emerged seeds; sound and larvae-concealed seeds）. We found that L. edwardsi removed, scatter hoarded and ate fewer larvae-emerged seeds than sound seeds. No difference was found between sound seeds and larvae-concealed seeds. These results suggest that sound and larvae-concealed seeds are more favored by L. edwardsi than larvae-emerged seeds. We posit that not only plants but also insects may benefit from the behavioral responses of hoarders to seed infestation under natural conditions
文摘Samples of pheromone lures used in boll weevil, Anthonomus grandis （Boheman）, eradication programs are routinely analyzed by Gas Chromatography （GC） to ensure lures are adequately dosed with grandlure, the synthetic aggregation phero- mone produced by male weevils. However, preparation of GC samples is tedious, time consuming, and requires a moderate level of experience. We examined the use of a commercially-available electronic nose （e-nose） for rapidly assessing the grandlure contents of lures. The e-nose was trained to recognize headspace collections of grandlure emitted from new lures and after lures were aged under field conditions for 4 d, 7 d, 10 d, and 14 d. Based on cross-validation of the training set, the e-nose was 82% accurate in discriminating among the different age classes of lures. Upon sampling headspace collections of pheromone from a different set of field-aged lures, the e-nose was 〈50% accurate in discriminating 4 d, 7 d, and 10 d aged lures from the other age classes of lures. However, the e-nose identified new and 14 d aged lure samples with 100% accuracy. In light of these findings, e-nose technology shows considerable promise as an alternative approach for rapidly assessing the initial grandlure contents of lures used in boll weevil eradication programs.
基金The financial assistance from the Swedish International Development Agency for some of the study (travel grant for Valantine Mbatchou)
文摘Objetive: To explore the potential insecticidal, ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora(Syn. Cassia tora) against cowpea weevil(Callosobruchus maculatus).Method: The activities were evaluated using standard protocols.In these bioassays, the cowpea seeds were used directly as an insect feed. The activity of the extract and isolated compounds were tested at concentrations of 100, 200 and 300 μg/mL and compared to neem oil and cinnamaldehyde(as standard positive controls). Phytochemical analysis of the ethyl acetate extract was done through a number of chromatographic techniques and the structures of the isolated compounds were established through comprehensive spectroscopic analysis including 2 D-NMR and ESI-MS studies.Results: Fractionation of the active ethyl acetate extract resulted in the isolation of one known anthraquinone,aurantio-obtusin(1) and a novel compound that was named as cassiatorin(2). Compounds1 and 2 showed comparable insect antifeedant properties with the positive controls while their insecticidal and ovipositor deterrent effects were far superior to the standard controls.Conclusions: It is thus concluded that Senna tora extracts and the isolated compounds(1 and2) may be employed in the postharvest management of stored cowpea seeds and as other crop protectants.
基金funded by the China Postdoctoral Science Foundation(E290D51135)。
文摘Callosobruchus maculatus(Fabricius,1775)(Coleoptera:Bruchinae)is a destructive agricultural pest that is harmful to beans worldwide and an important quarantine pest in China.It was divided into two phenotypes based on polyphenism:normal and flight forms.In this study,we first compared the morphological structures of the compound eyes of the two forms.According to the results of scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(micro-CT),and computer three-dimensional reconstruction,there are no differences in the structures of the compound eyes between the normal and flight forms except for the number of ommatidia.From the internal structure,the compound eyes have a biconvex cornea with open rhabdom and acone eye,crystalline cone directly connected with rhabdom,and no clear zone.It is a kind of apposition eye.Ommatidia facets range in shape from quadrilateral to hexagonal and some irregular shapes.On electroretinograms(ERGs),the normal and flight forms showed different spectral sensitivities:the normal form had the strongest response to ultraviolet light,whereas the flight form had the strongest response to white light.Behavioral assays revealed that the normal and flight forms showed completely opposite phototaxis behaviors;the flight form exhibited positive phototaxis,whereas the normal form exhibited negative phototaxis.This study not only enriches our knowledge on coleopteran compound eyes but also provides a foundation for in-depth research on the photoreceptor mechanisms of compound eyes,which may be useful in pest control management.
文摘Genetic comparison between Rhynchophorus ferrugineus （Coleoptera： Curculionidae： Rhynchophorinae） and other four Rhynchophorus spp. such as R. bilineatus, R. phoenicis, R. cruentatus and R. palmarum was investigated using partial sequences of Cytochrome c oxidase subunit I （COl） mitochondrial gene. The number ofpolymorphic sites ranged from 79 to 102 while the genetic distances ranged from 0.058 to 0.095. The number of polymorphic sites, genetic distances and phylogenetic relationships among R. ferrugineus and the other four tested species revealed that R.ferrugineus was more closely related to R. bilineatus while it was distantly related to R. palmarum. It is possible to rank the five tested species as follows： R.ferrugineus, R. bilineatus, R. phoenicis, R. cruentatus and R. palmarum. The result of this study is the first step of the revision of the uncertain taxonomic status and phylogenetic relationships among the Rhynchophorus genus. Further analysis should be performed using other Rhynchophorus species as well as other molecular markers.
基金supported by King Saud University, Deanship of Scientific Research, College of Science Research Center
文摘The Kingdom of Saudi Arabia is one of the leading date producing countries. Unfortunately, this important fruit crop is under great threat from the red palm weevil （RPW） （Rhynchophorus ferrugineus）, which is a highly invasive pest. Several techniques, including visual inspection, acoustic sensors, sniffer dogs, and pheromone traps have been tried to detect the early stages of a RPW infestation; however, each method has suffered certain logistical and implementation issues. We have applied laser induced breakdown spectroscopy （LIBS） for the early detection of RPW infestation. Through the analysis of the observed LIBS spectra of different infested and healthy samples, we have found presence of Ca, Mg, Na, C, K elements and OH, CN molecules. The spectra also reveal that with the population growth of the pest, the intensity of Mg and Ca atomic lines in LIBS spectra increases rapidly. Similar behavior is observed in the molecular lines of LIBS spectra. The obtained results indicate that the LIBS technique can be used for the early detection of RPW infestation without damaging the date palms.
文摘The red palm weevil （RPW） Rhynchophorusferrugineus is one of the most invasive insect pests causing massive damage on date palms over the world. Synthetic pyrethroid insecticide beta-cyfluthrin has been evaluated against developmental stages of RPW under laboratory conditions. These stages were exposed to residual film of the insecticide on transparent cups using a Potter precision laboratory spray tower. Percent mortality of males and females were recorded 0.5, 2.0 and 24 h after treatment. Furthermore, date palm offshoots were infested in mesh house, two months later, offshoots treated with 300 ppm （p.g/mL） beta-eyfluthrin using two methods dipping and injection. Bioassay test showed beta-cyfluthrin at 300 ppm caused 86,7% and 93,3% mortality against males and females after 2 h respectively with LC50 135.74 and 109.4 ppm. By increasing the concentration at 400 ppm, mortality reached 100% against males and females after 24 h, Developmental stages, eggs and larvae were more sensitive toward the insecticide, where at 120 ppm no eggs hatched after 96 h and 86.7% mortality was recorded at 200 ppm against larvae after 30 rain with LC50 93.19 ppm. In addition, dipping method of date palm offshoots in 300 ppm beta-cyfluthrin was a very convenient way to control all RPW stages compared to injection method. So, it possible to recommend this method for treating the date palm offshoots in such insecticide as one of the most important elements of integrated pest management for standardizing insecticide based quarantine protocols.
文摘The Red Palm Weevil （RPW）, Rhynchophorus ferrugineus （Olivier）, （Coleoptera, Curculionidae, Rhynchophorinae）, is an invasive species that is originated from Southeast Asia. It has invaded Middle East, several countries of the Mediterranean Basin, Caribbean （Island of Curacao, Netherland Antilles）, Lebanon and United States of America （Laguna Beach, Orange County, California） during the last three decades where it attacks palm trees. This study investigated the geographical variation among geographic populations of RPW collected from twelve invaded countries using cytochrome b （Cytb） and ITS2 partial sequences. The comparison among the Cytb sequences resulted in three different haplotypes designated as HB 1 to HB3. The three haplotypes were subdivided into two phylogenetic groups according to their geographic positions： （1） the ＂Multi-Continent＂ group containing HB 1 haplotype detected in eight populations belonging to three different Continents such as Africa-Egypt, Asia-Kingdom of Saudi Arabia and Turkey and Europe-Spain, Italy, Greece, Cyprus and France, and （2） the ＂Asian＂ group includes four populations from Iran （harboring HB2 haplotype）, Pakistan, UAE, and Oman （harboring HB3 haplotype）. This mitochondrial pattern of genetic diversity suggests that the tested RPW populations subdivided genetically into different sub-populations under the influence of genetic drift. According to these results we concluded that the twelve studied RPW populations are originating from different source populations in the RPW area of origin.
文摘The Red Palm Weevil （RPW）, Rhynchophorus ferrugineus （Olivier）, （Coleoptera, Curculionidae, Rhynchophorinae）, is an invasive species that is originated from Southeast Asia. It has.invaded Middle East and several countries of the Mediterranean Basin during the last three decades where it attacks palm trees. During the last three decades, multiple introductions of RPW to the Middle East, Europe and Caribbean （Island of Curacao, Netherland Antilles）, Lebanon and United States of America （Laguna Beach, Orange County, California） （USA） have occurred and the RPW is now a serious pest of many palm species. Duration of all life parameters varies significantly where the entire life cycle takes about 45 to 298 days. Different artificial diets were developed and were tested for mass rearing of RPW. Control of RPW is difficult due to the concealed nature of the life cycle of the pest. Integrated Pest Management （IPM） strategy has been applied successfully to deal with RPW problem. The IPM strategy consists of various preventive and curative methods; those methods were categorized in nine categories in this review. The main objective of this work was to review the existing knowledge on RPW＇s different aspects, with an ultimate aim of revealing the actual situation of the research on RPW.
基金Supported by National Keypoint Research and Invention Program of the Thirteenth(2017YFC1600804)
文摘Knowing the developmental states of stored grain insects, especially for the immature stages hidden in cereal kernel, such as Sitophilus zeamais, could be in favor of monitoring early and controlling effectively. Atlas and scale parameters on different developmental stages of S. zeamais in wheat kernel were captured and described by three-dimensional microscope of super depth of field observation. The four instars of larva, pre-pupa, pupa, new adult, old adult in kernel could be seen by dissecting the infested kernels. The length, height, and width of larva body increased with insect development and centralized the sizes corresponding to the four instars of larva. The length of larva body centralized near 554, 746, 1 462, and 2 147 μm. The height of larva body centralized about 388, 575, 847, and 1 651 μm. The width of larva body centralized near 340, 598, 798, and 1 568 μm. Head capsule width was in same size for each exuviating period, centralized near 203, 317, 535, and 603 μm, and got big sharply with the instar changed. Developmental duration of four larva instars was about 21 days reared in wheat, less than 28 days reared in maize as published. The atlas and description should be helpful for monitoring the S. zeamais development hidden in cereal kernels and designing control strategy.
文摘Plant diseases generate challenging problems in commercial, agriculture and pose real economic threats to both conventional and organic farming systems. The red palm weevil (Rhynchophorus ferrugineus) (RPW) is one of the most destructive pests of palms in the world. Nowadays, control methods revolve around treatments based on chemicals, biotechnological systems using semi-chemicals or the development of the sterile insect technique (hardly sustainable at this time) and biological control. Biological control as the use of natural microorganisms, extracted products from microorganisms or genetically improved to resist or eliminate of pathogens. Our aim was to evaluate the entomopathogenicity of indigenous Beauveria bassiana and Metarhizium anisopliae obtained in Gaza strip against larvae and adults of R. ferrugineus in order to identify indigenous strains potentially suitable for Red Palm Weevil biological control. B. bassiana & M. anisopliae were isolated from larvae and adult dead of RPW from different position of Gaza strip. Morphological analysis of the isolated fungi and molecular identification was determined using PCR technique. Also, the efficiency of the isolated fungi were evaluated under lab conditions and optimized as a biological agent. On the anther hand, the ability of treated RPW male to infect females is examined and calculated using Abbott's formula. Our results showed that the B. bassiana and M. anisopliae exhibited a good biological control agent against larvae and adults of RPW. The pathogenicity of the two most virulent isolates and the toxicity assay on larvae showed a highest mortality percentage nearly to 100% by 6 days after spraying the larvae with 3.4 × 108 spores/ml of B. bassiana. The mortality percentage reaches to 90% after spraying the larvae with 3.6 × 108 spores/ml of M. anisopliae. The mortality for the adults treated with pesticide arrives to 50% and the control group 10% at the same time. The results revealed that the infection of the adult males by Entomopathogenic fungi (EPF) can be disseminated into the healthy population, after RPW treatment with B. bassiana and M. anisopliae. Our research concludes that B. bassiana and M. anisopliae locally isolated can be used as biological very effective.
