Evaluation of the Insecticidal Activity of Powders of Ageratum conyzoide L. Leaves and Roots of Securidaca longepedunculata Fresen on the Germination Rate of Cowpea Infected with Callosobruchus maculatus

Cowpea is a vegetable that contributes to food security in Guinea. Despite its importance, more than 30% of its production is lost between harvesting, storage and consumption. The main cowpea pest is Callosobruchus maculatus. The commonly used control strategy is essentially based on chemicals whose use is toxic, expensive and restrictive. In the search for alternatives to chemical control, this work was undertaken to evaluate the insecticidal potential of Ageratum conyzoid leaf powders and Securidaca longepedunculata roots. Powder toxicity and insecticidal efficacy tests were performed separately on groups of 20 Callosobruchus maculatus using 3 doses of Ageratum conyzoid leaf powders and Securidaca longepedunculata roots in jars each containing 100 g cowpea. The mortality of Callosobruchus maculatus and the impact of powders were noted respectively for 96 h and 4 months after infestation. The germination capacity of the treated seeds was assessed at the start of the study. Doses of 1 and 8 g of Ageratum conyzoides leaf powders and Securidaca longepedunculata roots were applied respectively to every 100 g of cowpea and led to 100% mortality of Callosobruchus maculatus. At these same doses, more than half of the treated seeds were attacked during the 4 months of storage. Germination tests have shown that powders of Ageratum conyzoides leaves and roots of Securidaca longepedunculata have no negative effect on the germination power of cowpea seeds. Therefore, they could be considered as excellent bio-insecticides that socio-professional strata (farmers and warehouse workers) can use in the fight against cowpea insects intended for storage.

Attraction of bruchid beetles Callosobruchus chinensis (L.) (Coleoptera: Bruchidae) to host plant volatiles

Host-plant volatiles play an important role as cues for herbivores in search of resources, mates and oviposition sites in complex environments. Plant volatile-based attractants can be developed for pest monitoring and control. Previously, we indicated that mated female adults of Callosobruchus chinensis showed choice preference behavior toward 2-hexenal and benzaldehyde. Our objective here was to investigate the synergistic effect of host-derived attractive volatiles in attracting C. chinensis under laboratory and field conditions in Shanxi Province, China. We hypothesized that the ratio and concentration of volatiles derived from Vigna radiata play critical roles for C. chinensis in locating this host. Therefore, we collected and identified the volatiles of mungbean by using headspace collection and GC-MS. The effectiveness of different ratios and concentrations of two compounds (2-hexenal and benzaldehyde) that elicit C. chinensis searching behavior were examined in Y-tube olfactometer assays. The combination of 300 μg μL^–1 2-hexenal and 180 μg μL^–1 benzaldehyde loadings exhibited a synergistic effect on attracting C. chinensis (82.35%). Compared to control traps, the adults were significantly attracted to traps baited with blends, and more attraction to females than males was found for blend traps in the field experiments. Our results suggest that blends of this specific concentration and ratio of benzaldehyde and 2-hexenal can be used in traps as attractants for C. chinensis monitoring and control in the field.

Evaluation of the dust and methanol extracts of Garcinia kolae for the control of Callosobruchus maculatus (F.) and Sitophilus zeamais (Mots)

Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Callosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects, none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%-100% whereas in S. zeamais, the mortality ranged from 87.5%-100% and 70%-100% in concentrations of 1 g extract＋3 ml methanol and 1 g extract＋5 ml methanol, respectively, from 24 to 48 h. The least concentration of 1 g extract＋l 5 ml methanol had no significant lethal effect on Sitophilus zeamais.

Chemical Composition and Bioactivity of Lippia adoensis Hochst ex.Walp(Verneneaceae) Leaf Essential Oil Against Callosobruchus maculatus Fabricius(Coleoptera: Chrysomelidae)

Essential oil （EO） of Nigeria-grown Lippia adoensis leaf was analyzed using gas chromatography mass spectrometry （GCMS） and its fumigant and repellent properties against Callosobruchus maculatus were evaluated. Sixteen compounds predominated by monoterpenes were identified. The major compounds were Eucalyptol （28.36%）, α-Terpineol （25.99%）, γ-Terpinene （15.24%）, α-Pinene （5.08%）, 1H-Cyclopropa[a]naphthalene （4.25%） and 1, 3, 6, 10-Dodeeatetraene （3.74%）. Percentage mortality due to fumigant toxicity was dose- and exposure period-dependent. One hour after treatment （HAT）, application of L. adoensis leaf EO at 107 μL· L^-1 air caused significantly （p〈0.05） higher mortality （50.00%） than 0.00% mortality observed at 0-53 μL· L^-1 air, but not significantly （p〉0.05） different from 22.50% observed in 80 μL· L^-1 air. At 3 HAT, application ofL. adoensis EO at 80 μL· L^-1 air caused significantly higher mortality （90.00 %） than mortality observed at 0 μL· L^-1 air. At 6 HAT, application of L. adoensis EO at 53-107 μL· L^-1 air caused significantly higher mortality （100.00 %） than that was observed in the control. The same trend was observed at 12 HAT where 100 % mortality observed in 27-107 μL· L^-1 air was significantly greater than 13.33 % observed in the control. At 3 HAT, percentage repellence was significantly （p〈0.05） affected by doses. Application of EO at 10-30 μL· cm^2 caused class V repellence （86.67%-100%） compared with the control which caused class I repellence （0-20%）.

Combination of Piper guineense Essential Oil with Cowpea Varietal Resistance in Control of Cowpea Seed Beetle, Callosobruchus maculatus Fabricius (Coleoptera： Chrysomelidae： Bruchinae)

To reduce the risks associated with over-dependence on synthetic insecticides and ensure leguminous food security, an experiment was conducted to evaluate the potentials of integrating Piper guineense essential oil （PgEO） with cowpea varietal resistance in the control of cowpea seed beetle, Callosobruehus maculatus Fabricius. Four cowpea varieties （Sokoto, Drum, Oloyin and Gwallam） were studied. Data collected included oviposition, progeny emergence, Reproductive Efficiency （RE） and Percentage Seed Damage （PSD）. At first filial generation, numbers of eggs laid on Oloyin variety treated with 25 μL PgEO per 25 g cowpea seeds （2.15） were significantly （p〈0.05） lower than the values obtained in untreated cowpea （3.61） and hexane-treated seeds （3.07）. C. maculatus RE on Oloyin （33.73） was significantly （p〈0.05） lower than values obtained on other varieties （47.34-54.67） for seeds without PgEO; and were significantly greater than 0.00 observed on Oloyin seeds treated with 50 pL PgEO. PSD on Oloyin （6.63%） was significantly （p〈0.05） lower than the values obtained on Sokoto （10.04%） and Drum （9.79%） for seeds without PgEO, while there was no damage in Oloyin treated with 50 pL PgEO. Significantly （p〈0.05） lower F2 progeny emergence occurred on Oloyin （4.02） and Sokoto （4.71） compared with Drum （9.03） and Gwallam （6.07） from the untreated cowpea seeds. The results implied that application of PgEO to Oloyin gave better protection from infestation of C. maculatus than other varieties. Hence, combination of varietal resistance with PgEO for management ofbruchid could be an effective mean of improving cowpea food security.

Effects of Initial Infestation Levels of Callosobruchus maculatus (F.)(Coleoptera: Chrysomelidae) on Cowpea and Use of Nicotiana tabacum L.Aqueous Extract as Grain Protectant

This study determined the effects of initial infestation of cowpea seeds （Ife brown variety） with different insect densities （0, 2, 4 and 6 pairs per 50 g seeds） of Callosobruchus maculatus （F.） and evaluated the effects of aqueous leaf extract of Nicotiana tabacum L. on C. maculatus in the laboratory. It was observed that adult beetle population increased significantly （p〈0.05） with increase in insect density. The increase in population of beetles and corresponding weight loss of the seeds in different levels of infestation showed that the cowpea variety was susceptible to beetle infestation, emergence and survival of progeny. Significantly more adults emerged on higher infestation compared to lower and no infestation. In Nigeria, Nicotiana tabacum L. is a locally available plant, with known insecticidal properties. The plant leaf extract was easily extracted with water and confirmed its effectiveness as a protective agent for stored cowpea seeds. Experiment was conducted to assess the effects of aqueous extracts ofN. tabacum at 0, 0.1, 0.2 and 0.3 mL＂ 50 g-1 cowpea seeds on C. maculatus. Data was recorded and showed varying levels of effectiveness against C. maculatus. Result showed that seed appearance was dependent on levels of insect population, while N. tabacum aqueous extract exerted effects on survival of C. maculatus. Aqueous leaf extract of N. tabacum probably contained some insecticidal properties which might have significantly conferred beetle mortality and reduced beetle emergence leading to a decrease in seed weight loss.

Growth and Development of Callosobruchus chinensis L.(Coleoptera:Bruchidae) on Different Beans

[ Objective ] The paper was to study the growth and development characteristics of Callosobruchus chinensis L. on different beans, and to explore the resistance of different beans to C. chiaensis. [ Method] The egg hatchability, growth and development of larva and adult of C. chinensis L. on different beans were observed in the laboratory at 30℃. [ Result] All the eight kinds of beans were spawned, but there were differences in egg hatchability among different beans. The egg hatchahility on Vigna radiate was the highest of （78.47 ±6.70） %. After hatching, larvae only drilled into grains of V. radiate, Vigna umbellate, Vicia faba, Pisum sativum and Cicer arietiaum, but there were significant differences in generation survival rate. The generation survival rate on V. radiate was the highest of （68.75 ±9.08）% and that on 1/. faba was the lowest of （26.93± 10.28 ）%. The development duration of C. chinensis on V. radiate was the shortest of （34.78 ± 2.02）d; the intrinsic rate of increase and finite rate of increase were greater of 0. 041 09 and 1. 041 95, respectively. [ Conclusion] A large number of C. chinertsis could be reproduced within a short period if feeding on V. radiate.

Efficacy of Groundnut Oil, Wood Ash, Sand and Some Plants Powders against Callosobruchus chinensis in Cowpea Seeds

This study was conducted under Laboratory of Plant Protection Department, Faculty of Natural Resources and Environmental Studies, University of Kordofan, Elobeid in Sudan, during March-June 2015 to assess the effect of six treatments on germination of cowpea seeds infested by Callosobruchus chinensis Linn., a serious Coleoptera pest which damages cowpea seeds. The agents used were groundnut oil, wood ash, sand, neem leaves powder, Rabal leaves powder and hot pepper powder. In the lab bioassay, the results obtained due to the infestation by C. chinensis showed that there were highly significant differences （P 〉 0.01） in the number of holes per 100 cowpea seeds between the different treatments at intervals of one month, and up to the end of the storage period, the numbers of holes per 100 cowpea seeds were 44, 740, 859, 856, 841 and 892 holes in the treatments, respectively. The germination of seeds treated with groundnut oil was 60%, while it was zero for the other treatments. It was concluded that the groundnut oil made creamy coat on the seeds and prevented the development of eowpea beetle infestation. Hence, it can be used by farmers at local levels to protect seeds for cultivation.

The Role of Seed Coat and Its Pigmentation on the Acceptance of Bambara Groundnut (<i>Vigna subterranea </i>L. Verdc.) Cultivars by the Cowpea Beetle, <i>Callosobruchus maculatus</i>(F.)

Bambara groundnut, Vigna subterranea is an important legume crop that is adaptable to the dry regions of Africa. It is a major source of protein to people in many parts of Africa. One major constraint to increased production of the crop is the incidence of the storage pest Callosobruchus maculatus which causes significant weight loss to seeds in storage. The preference of the cowpea beetle C. maculatus for a particular seed coat colour was determined using four different colour types of bambara groundnut in an arena. The olfactory attractiveness of testa against cotyledon and cotyledon against whole grain was carried out in an olfactometer. Oviposition preference of C. maculatus on the different seed colours was determined. In the arena experiment significantly more of the beetles showed preference for cream and mottled seeds than red and black seeds. Significantly more beetles chose seeds with testa over decorticated seeds as well as whole grain over decorticated seeds. Colour significantly affected the seeds as oviposition sites. Significantly fewer eggs were laid on red and black seeds than cream seeds in both the choice and no choice tests (P < 0.0001). Thus for the purpose of reducing losses of seeds in storage it is advisable to cultivate red- and black-coloured seeds which showed lower acceptability to C. maculatus as oviposition site.

Potential Reproductive Activity of Callosobruchus subinnotatus Pic. （Coleoptera： Bruchinae）, Bambara Groundnut （Vigna subterranea Verd.） Depredator

Callosobruchus subinnotatus Pic. （Coleoptera： Bruchinae） is the most important depredator of Bambara groundnut seeds （Vigna subterranea Verd.） in West Africa. In view of an efficient control of its populations, some of the biological parameters of C. subinnotatus were determined under laboratory conditions （30 ± 2℃; 72 ± 2% HR; 12h： 12h LD）. The results have shown that the mean lifespan of females （11.36±1.85 days） is shorter than that of males （15.14 ±2.4 days）. The female lays 80.83% eggs within the first 6 days after her emergence with a mean fecundity of 121.34 ±27.62 eggs. The means egg fertility, survival and adult emergence rates are respectively 96.19±1.45%, 97.72 ± 1.08% and 94.01± 2.14%. The sex ratio is in favor of males with a mean of 0.845 ± 0.08. The monitoring of adult emergence in connection with their reproductive status showed that the offspring of C. subinnotatus consists of two physiotypes, a reproductive type that appears during the first 8 days of emergence with a short development time （28.35± 3.36 days） and a non reproductive type that appears from the 9th day of emergence with a longer development time （37.92 ± 3.92 days）.

COMPARATIVE BIOLOGY OF TWO GEOGRAPHICAL POPULATIONS OF THE SOUTHERN COWPEA WEEVIL, CALLOSOBRUCHUS CHINENSIS (L.) (COLEOPTERA: BRUCHIDAE) IN SOUTHWEST CHINA

The differences of bionomics and ecologics of the two populations of Callosobruchus chinensis on mung bean (Vigna radiatus) at six constant temperatures ( 20, 25, 28, 30, 32, 35℃) and 75% r. h. were researched. ANOVA showed that temperature affected the developmental period and fertility significantly (P<0.05). T-test indicated there was significant difference of the combined immature stages between the two geographical populations at 25 and 32℃ (P<0.05). The average oviposition between the two geographical populations differed significantly at the same temperature (P<0.05). At 30℃ and 75% r. h., effects of 5 commercially grown legume seeds on development and reproduction of the two geographical populations of Callosobruchus chinensis (L.) were researched. The results showed that broad bean and soybean were more suitable for increase for Xichang population in terms of r m values. The adult weight and diameter of emergency hole of the two populations were also compared. According to the differences in the characteristics of development, reproduction, and damage to host seeds between the two geographical populations, conclusion can be drawn that both are different geographical populations.

Assessment of bone charcoal dusts of six species of mammal for the postharvest control of Callosobruchus maculatus Fabricius(Coleoptera:Chrysomelidae)infestations of cowpea seeds:can the charcoal dust affect seed viability in laboratory and in field?

Objectives:The possibility that bone charcoal dusts of some species of mammal will control the major insect pest of stored cowpea seeds and the implications on seed viability(after pest control process)were investigated in the laboratory at ambient temperature(30±3°C)and relative humidity(70±5%)and in field.Materials and Methods:Standard entomological and agronomical techniques were used.Results:The results showed that at 1.0%w/w dosage,the bone charcoal dusts of Ovis aries and Bos taurus were more effective than permethrin standard insecticide in killing adult Callosobruchus maculatus Fab.infesting cowpea seeds in storage.Bos taurus had a faster action speed than permethrin at 1.0%w/w.At 1.5%w/w of dust,all the species of mammal investigated deterred oviposition considerably in C.maculatus females,whereas only the bone charcoal dusts of O.aries and Sus scrofa were comparable with permethrin in suppressing adult emergence and seed damage;S.scrofa only was comparable with permethrin in reducing larval density.Bone charcoal dusts of O.aries and S.scrofa require chemical and olfactory analyses to know if they might have caused irritation to the insects and disrupted insect circadian rhythm,affecting behaviour and mating activities,adversely.The bone charcoal dusts of the six species of mammal at a highest test dose of 1.5%w/w allowed high seed viability in both laboratory and field.Conclusion:The study recommends the use of bone charcoal dusts of O.aries and S.scrofa at economical-and quality-favourable dose 1.5%w/w for managers seeking to control C.maculatus insect attacking cowpea seeds in storage.The transitive components of the bones,abrasion of the insect epicuticle lipid layer by the charcoal dust,and combustion-related toxic factors were responsible for the insecticidal activities of the bone charcoal dusts of the mammals.

Insecticidal toxicity of two bruchid-resistant cowpea cultivar powders as cowpea seed protectants against Callosobruchus maculatus(Fab.)(Coleoptera:Chrysomelidae)

Toxicity of bruchid-resistant cultivars MIT04K-399-1 and MIT07K-299-92 powders as cowpea protectants against Callosobruchus maculatus(Fab.)was investigated at an ambient temperature of 28±2°C and a relative humidity of 75±5%.Their efficacy was tested at dosage,0.5,1.0,1.5,2.0,2.5,and 3.0 g/20 g of cowpea seeds on adult mortality,oviposition,adult emergence,progeny development,seed damage,weight loss,and Beetle Perforation Index(BPI)by cowpea bruchid.The result showed that toxicity of the bruchid-resistant cowpea cultivar powders on adult bruchid is dosage-and time-dependent.At a dosage of 3.0 g/20 g,cultivars MIT04K-399-1 and MIT07K-299-92 powders achieved 70%and 72.5%lethal effect on adult C.maculatus after 4 days of treatment,respectively.Oviposition and percentage adult emergence of C.maculatus decrease with an increase in powder dosage.Conversely,reduction in progeny development of C.maculatus increases with an increase in powder dosage.The mean number of adult emergence decreased at 2 g/20 g,2.5 g/20 g and 3 g/20 g.The MIT04K-399-1 and MIT07K-299-92 powders significantly affected egg development.The MIT07K-299-92 powder was more effective against oviposition and adult emergence at higher concentrations than MIT04K-399-1 powder,an effect that was not significantly different(P>0.05)from each other.The BPI of 9.1 and 6.2 was recorded on cowpea seeds treated with MIT04K-399-1 and MIT07K-299-92 powders at a dosage of 3 g/20 g,respectively.The fear of residual toxicity on nontargeted organisms is not associated with the use of resistant cowpea cultivars as seed protectant.Subsistence farmers are familiar with the technology involved in the preparation and application of powders as protectants.Integration of bruchid-resistant cowpea cultivars MIT04K-399-1 and MIT07K-299-92 powders into the management of coleopteran pests will ensure availability of viable seeds for future farming in developing nations such as Nigeria.

Chemical Composition of Different Extracts of Conyza bonariensis: Insecticidal and Nematicidal Activities

C. bonariensis (L.) Cronq. known as hairy fleabane was first described in Argentina but it is now widely spread through most warmer regions of Europe, Africa, Asia, the Caribbean and Central America. In this work, a chemical analysis by liquid and gas chromatography coupled with mass spectrometry of the whole plant, aerial part, flowers and roots extracts of C. bonariensis harvested in Togo (West Africa) was carried out. Two acetylenic compounds Lachnophyllum ester and limonene were identified as the main components of essential oils while Lachnophyllum and Matricaria lactones were dominant in chloroform extracts. Based on the plant chemical compositions, essential oils and chloroform extracts were tested on cowpea weevil Callosobruchus maculatus adults which are considered as one of the most cosmopolitan pests of stored beans, and on freshly hatched second-stage juveniles of root-knot nematode Meloidogyne incognita. Results showed that the whole plant essential oil demonstrated an LC50/24h value of 1.75 μL oil/L air on C. maculatus while at 3.91 μL oil/L air, it showed 100% mortality. Furthermore, the plant root chloroform extracts partitioned in diethyl ether-hexane mixture showed the strongest nematicidal activity with an LC50/72h value of 0.47 mg/mL. Our findings suggest that the widely diffused plant C. bonariensis and its acetylenic constituents could be considered as potent botanical insecticidal and nematicidal agents.

极限温度对绿豆象及绿豆种子的影响

对绿豆[Vigna radiata(L.)Wilczek]储藏期间害虫绿豆象(Callosobruchus chinensis L.)各虫态对极限温度的耐受性进行了观察。结果表明,蛹和幼虫耐极限高、低温的能力均大于成虫和卵;蛹是绿豆象最耐低温的虫态,-5℃时完全杀灭蛹需要256 h,-10℃时完全杀灭卵、幼虫、蛹均需32 h,而杀灭成虫仅需8 h,-20℃防治所需时间较短,4 h即可完全防治绿豆象;蛹也是绿豆象最耐高温的虫态;45℃处理下完全杀灭需要32 h,而50℃防治见效较快,4 h即可完全防治绿豆象;极限高温处理对绿豆种子生命力和萌发率均无显著影响。利用极限温度可有效防治绿豆象且对绿豆种子无影响,在保证食品安全、促进绿色储粮等方面有重要的应用价值。

绿豆象的辐照致死效应研究

研究了60Co射线源对绿豆象(Callosobruchus chinensis L.)的致死效果,以探索其用于防治绿豆象的可行性。通过60Co射线对绿豆象卵、幼虫、蛹和成虫进行辐照,辐照剂量为0、20、40、80、160、320 Gy。结果表明,60Co射线辐照对绿豆象卵、幼虫、蛹和成虫的LD50分别为19.16、21.19、31.86、73.27 Gy,表明绿豆象成虫对60Co射线辐照的耐受能力最强。高剂量辐照后绿豆生命力和发芽率都有所降低,但是差异不显著。320 Gy能有效抑制卵的孵化(孵化率0)、蛹的羽化(羽化率7.33%)、造成幼虫(死亡率100%)和成虫的死亡(死亡率90.67%)。建议采用320 Gy的60Co射线辐照作为有效防治绿豆象的参考剂量。

绿豆象在不同豆类上的生长发育研究

在室内30℃恒温条件下,饲养观察了绿豆象(Callosobruchus chinensis L.)在不同豆类的卵孵化率、幼虫和成虫的生长发育历期。结果表明,绿豆象在供试的8种豆粒上均能产卵,但是卵在不同豆类上的孵化率间存在差异。其中,在绿豆上卵孵化率最高,为(78.47±6.70)%。卵孵化后,幼虫仅在绿豆、红小豆、豌豆、蚕豆和鹰嘴豆5种豆粒上蛀入危害,但是世代存活率间存在显著差异,在绿豆上世代存活率最高,为(68.75±9.08)%,蚕豆上的世代存活率最低,为(26.39±10.28)%;绿豆象在绿豆上世代发育历期最短,为34.78±2.02 d,内禀增长率和周限增长率均较大,分别为0.041 09和1.041 95。以绿豆为食物,可以在短时间内繁殖出大量的绿豆象。

四纹豆象在不同豆类上的生长发育研究

在室内温度30℃、相对湿度70%条件下,以绿豆、小豆、豌豆、蚕豆、鹰嘴豆、大豆、多花菜豆和普通菜豆为食料,研究四纹豆象(Callosobruchus maculatus Fabricius)卵、幼虫和成虫的生长发育历期、成活率及成虫繁殖力。结果表明,四纹豆象在供试的8种豆类上均能产卵,但仅在绿豆、小豆、豌豆、蚕豆、鹰嘴豆上能完成其生活史。其中,在蚕豆上卵历期最长,为(5.80±0.85)d,且与在其他豆类上的卵历期存在显著性差异;以小豆为食料的四纹豆象卵孵化率最高,为(73.61±5.24)%,在绿豆上卵孵化率次之,为(72.92±2.08)%,且与豌豆、蚕豆、鹰嘴豆上差异显著;卵孵化后,幼虫仅在绿豆、小豆、豌豆、蚕豆和鹰嘴豆上蛀入为害,在蚕豆上四纹豆象世代发育历期最长,为(47.75±3.50)d,且与在绿豆、小豆、鹰嘴豆上差异显著;四纹豆象在小豆上世代存活率最高,为(59.03±9.39)%,且与绿豆、豌豆、蚕豆和鹰嘴豆4种豆类差异显著,内禀增长率和周限增长率也均较大,分别为0.029 3和1.029 7。

Construction of an integrated map and location of a bruchid resistance gene in mung bean

Bruchid beetle(Callosobruchus chinensis) poses a serious threat to the production and storage of mung bean(Vigna radiata). Mapping bruchid resistance(Br) will provide an important basis for cloning the responsible gene(s) and elucidating its functional mechanism, and will also facilitate marker-assisted selection in mung bean breeding. Here, we report the construction of the genetic linkage groups of mung bean and mapping of the Br1 locus using an RIL population derived from a cross between Berken, a bruchid-susceptible line, and ACC41, a bruchid-resistant line. A total of 560 markers were mapped onto 11 linkage groups,with 38.0% of the markers showing distorted segregation. The lengths of the linkage groups ranged from 45.2 to 117.0 c M with a total coverage of 732.9 c M and an average interval of1.3 c M between loci. Br1 was located on LG9 between BM202(0.7 c M) and Vr2-627(1.7 c M).Based on 270 shared SSR markers, most of the linkage groups were assigned to specific chromosomes. These results should further accelerate the genetic study of this crop.

Fumigant and repellent properties of sesquiterpene-rich essential oil from Teucrium polium subsp,capitatum(L.)

Objective:To test fumigant and repellent properties of sesquiterpene—rich essential oil from Teucrium polium subsp.capitation(L.).Methods:The fumigant toxicity test was performed at(27±1)℃.(65± 5)%relative humidity,and under darkness condition and 24 h exposure time.The chemical composition of the isolated oils was examined by gas chromatography—mass spectrometry.Results:The major compounds were α-cadiuol(46.2%),earyophyllene oxide(25.9%),α muurolol epi(8.1%),cadalene(3.7%) and longiverbenone(2.9%).In all cases,considerable differences in mortality of insect to essential oil vapor were observed in different concentrations and exposure times.Callosobruchus maculatus(C.maculates)(LC_(50)=148.9μL/L air) was more susceptible to the tested plant product than Teucrium castaneum(T.castaneum)(LC_(50)=360.2μL/L ain based on LC_(50)values.In the present investigation,the concentration of 3μ L /mL acetone showed 60% and 52% repellency against T.casteneum and C.maculatus adults,respectively.Conclusions:The results suggests that sesquiterpene—rich essential oils from the tested plant could be used as a potential control agent for stored—product insects.