963 research outputs found
Oviposition and reproductive performance of Habrobracon hebetor (Hymenoptera: Braconidae) on six different pyralid host species
Citation: Ghimire, M., & Phillips, T. (2014) Oviposition and Reproductive Performance of Habrobracon hebetor
(Hymenoptera: Braconidae) on Six Different Pyralid Host Species. Annals of the Entomological Society of America, 107(4), 809-817.
https://doi.org/10.1603/AN14046Habrobracon hebetor Say (Hymenoptera: Braconidae) is a gregarious ecto-parasitoid that attacks larvae of several species of Lepidoptera, mainly pyralid moths infesting stored products. Host quality strongly influences the reproductive success of the parasitoid. In this study, we assessed the reproductive performance of the parasitoid, H. hebetor in a series of laboratory experiments using six different pyralid host species: Indianmeal moth, Plodia interpunctella (Hübner), Mediterranean flour moth, Ephestia kuehniella (Zeller), almond moth, Ephestia cautella (Walker), rice moth, Corcyra cephalonica (Stainton), navel orangeworm, Amyelois transitella (Walker), and greater wax moth, Galleria mellonella L. Experiments were conducted using petri dishes (100 by 15 mm) as experimental arenas at 29 ± 1°C, 65 ± 5% relative humidity, and a photoperiod of 14:10 (L:D) h. Two-day-old H. hebetor females were introduced singly into experimental arenas and given a single host larva every day throughout their lifetime. The numbers of hosts paralyzed and parasitized, numbers of eggs laid each day on each host, egg-to-adult survivorship, and progeny sex ratio were used as parameters for assessing host suitability. Paralysis of hosts by H. hebetor females was significantly affected by host species. H. hebetor paralyzed >95% of the preferred host larvae that were offered and also used ≈90% of those for oviposition. Daily fecundity was highest on G. mellonella (22.1 ± 0.4) and C. cephalonica (21.6 ± 0.3), and lowest on E. cautella (13.4 ± 0.2). The egg-to-adult survivorship and progeny sex ratio were also significantly affected by the host species. The highest percentage of parasitoid survival was on A. transitella (75.7 ± 2.0) and C. cephalonica (75.4 ± 2.5), and lowest on G. mellonella (49.7 ± 4.8). Our studies clearly showed that H. hebetor females can paralyze and lay eggs on several pyralid species, but it cannot necessarily develop and reproduce optimally on all host species that it can paralyze and parasitize
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Bio-mechanical risk factors for uterine prolapse among women living in the hills of west Nepal: A case-control study.
OBJECTIVE:To investigate whether heavy load carrying, wearing a patuka, and body position at work are risk factors for uterine prolapse among Nepali women. METHODS:Community-based case-control study of 448 women (170 cases of uterine prolapse; 278 controls) aged 18-60 years in Kaski district, Nepal was conducted. Women diagnosed with uterine prolapse were cases. Two controls were recruited for each case, frequency-matched by residential area and age. Multivariate logistic regression was used to investigate associations between outcome and exposures. RESULTS:No association of heavy load carrying with uterine prolapse was observed; women who never used a patuka had lower odds of uterine prolapse (odds ratio = 0.18, 95% confidence interval = 0.05-0.71). Women working in a sitting position had higher odds than those working in a standing position (odds ratio = 2.94, 95% confidence interval = 1.74-4.96), as did women who mainly worked in a bending position (odds ratio = 2.45, 95% confidence interval = 1.12-5.34). Housewives were more prone to uterine prolapse than women engaged in farming (odds ratio = 2.13, 95% confidence interval = 1.31-3.47). CONCLUSION:Using a patuka, occupation, and body position during work were all associated with uterine prolapse. No association was found with heavy load carrying, although that might be attributable to the cross-sectional nature of study recruitment
Does program linking with insurance makes agriculture insurance sustainable?
Agriculture insurance is most common forms of risk transfer in agriculture. It is often compulsory for borrowers of agricultural loans in low and middle income countries. This study tries to find out the status of compulsory agriculture insurance in Nepal and its sustainability through answering question “are compulsory agriculture insurance programs making agricultural insurance sustainable? Or we have to think differently for its sustainability. Household survey were conducted using pre-tested semi structured questionnaire in eight districts. Altogether 377 insurer farmers (132 crop and 245 livestock farmers) were selected from the list of target population using simple random sampling technique. Similarly, five cases were selected from the study districts. Result shows that Government of Nepal (GoN) has developed both cost of production and value based insurance products based on farmers demand. Basically, premium rate is fixed as five percent to cost of production based and seven percent to value based insurance for most of crops and livestock. Different governments programs such as youth self-employment program, youth focused program, spring rice promotion program and other grant/subsidy programs under different mega projects of GoN have started to link agriculture insurance with their programs. Insurance has been made mandatory to get such any subsidy support from the government for promoting agriculture insurance simultaneously. However, this study found that this strategy did not adequately work. But if they feel the enterprises is risky and realize the importance of agriculture insurance and can get higher returns from the enterprises, they were willing to participate in agriculture insurance. Most of farmers who participated in government grant program have limited understanding of crop insurance so that they have discontinued insurance after the end of grant/subsidy program. Therefore, it is necessary to revisit the existing provision of grant linked insurance and need to focus more on creating awareness on importance of agriculture insurance for its sustainability
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