The inhibition of molting fluid enzymes of Pod borer,Helicoverpa armigera (Hubner) by an aspartic protease inhibitor: Its effects on insect development

In this study, the inhibition of molting fluid enzymes from Helicoverpa armigera by an aspartic protease inhibitor, Alkalophilic Thermophilic Bacillus Inhibitor (ATBI) purified from Bacillus sp. is reported. The in vitro experiments showed 80% inhibition (IC₅₀= 48 µM) of hemoglobin hydrolyzing and 95% inhibition (IC₅₀= 35 µM) of chitin hydrolyzing activity from molting fluid by ATBI (IC₅₀ value is the ATBI concentration for 50% inhibition of total enzymatic activity). The treatment of H. armigera larvae with 400 µM ATBI recorded 20% larval mortality, 27.77% deformed pupae and 12.22% deformed adults. The LC₅₀ value (Concentration of ATBI calculated to give 50% mortality) calculated for insect population was found to be 330.06 µM. Similarly, significant variations in mean larval and pupal weight, no. of eggs laid per female and percent hatching of eggs were observed at higher concentrations of ATBI. The results may provide the basis for the selection of non-host inhibitors to develop a H. armigera insecticide formulation.     

捕食性瓢虫的体型大小影响其偏好捕食防御性强的猎物吗?（英文）

【目的】尽管瓢虫表现出种间和种内特异性体型大小的变异,但是瓢虫体型大小的变异是否会改变其选择捕食防御性强(即表现出各种防御反应,包括积极躲避捕食、挣脱捕食者或频繁利用防御性化学物质)的猎物,这一问题尚不清楚。本研究中,我们假设不论体型大小,捕食性瓢虫七星瓢虫Coccinella septempunctata(L.)和六斑月瓢虫Menochilus sexmaculatus(Fab.)都将增加其对猎物萝卜蚜Lipaphis erysimi(Kaltenbach)的捕食,只要猎物处于防御性强的龄期,原因是处于防御性强的龄期的猎物体型大且更有活力。【方法】我们将萝卜蚜4龄若虫期作为防御性强的龄期,将2龄若虫期作为防御性弱的龄期,评价七星瓢虫和六斑月瓢虫这两种瓢虫的大型和小型变异体对萝卜蚜的偏好性。【结果】结果表明,六斑月瓢虫的大型和小型雌性变异体更多地捕食防御性弱的萝卜蚜,而七星瓢虫的大型和小型雌性变异体分别对防御性强和防御性弱的萝卜蚜捕食较多。在混合饲料上,七星瓢虫雌性变异体对两类蚜虫的捕食百分比相似,而六斑月瓢虫变异体对防御性弱的萝卜蚜的捕食百分比较高。尽管随着七星瓢虫雌虫体型的增大而对两类猎物的捕食增多,但随着六斑月瓢虫雌虫体型的增大,只对防御性强的蚜虫的捕食量增加。【结论】本研究结果与我们的假设相反,并证明了:(1)小型瓢虫更多地只是捕食防御性弱的猎物,而大型瓢虫选择性地捕食防御性强的猎物;(2)在瓢虫种内和种间,随着捕食者体型的增大,对防御性强的猎物的偏好性增加。可将这些结果用于瓢虫的室内大规模饲养,以提高对萝卜蚜的生物防治。     

Varietal resistance, population dynamics and timing insecticidal application with peak oviposition by Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae) on rice

The flight activity of yellow stem borer Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae) peaked in the months of April-May, May-June, August-September and October. The number of egg masses and the number of adults attracted to light sources were the indicators of S. incertulas flight activity. The rice varieties TKM6, IR22, IR60, IR66 and IR74 were infested at 7, 10, 12 and 16 wk after planting with 5, 10, 20 and 40 neonates of S. incertulas. All varieties except IR66 were susceptible to dead heart damage by S. incertulas. When the rice varieties TKM6, BPIRi2, BPIRi4, IR22, IR36, IR60, IR66 and IR74 were treated with carbofuran insecticide at the time of peak oviposition by S. incertulas in the field, the dead heart damage on all the varieties was significantly reduced in comparison with the untreated plots. Indiscriminate routine insecticidal treatments (fixed schedule) can be replaced by a treat-when-necessary schedule based on the population dynamics of S. incertulas.     

Mapping of stripe rust resistance gene in an <Emphasis Type="Italic">Aegilops caudata</Emphasis> introgression line in wheat and its genetic association with leaf rust resistance

A pair of stripe rust and leaf rust resistance genes was introgressed from Aegilops caudata, a nonprogenitor diploid species with the CC genome, to cultivated wheat. Inheritance and genetic mapping of stripe rust resistance gene in backcross-recombinant inbred line (BC-RIL) population derived from the cross of a wheat–Ae. caudata introgression line (IL) T291-2(pau16060) with wheat cv. PBW343 is reported here. Segregation of BC-RILs for stripe rust resistance depicted a single major gene conditioning adult plant resistance (APR) with stripe rust reaction varying from TR-20MS in resistant RILs signifying the presence of some minor genes as well. Genetic association with leaf rust resistance revealed that two genes are located at a recombination distance of 13%. IL T291-2 had earlier been reported to carry introgressions on wheat chromosomes 2D, 3D, 4D, 5D, 6D and 7D. Genetic mapping indicated the introgression of stripe rust resistance gene on wheat chromosome 5DS in the region carrying leaf rust resistance gene LrAc, but as an independent introgression. Simple sequence repeat (SSR) and sequence-tagged site (STS) markers designed from the survey sequence data of 5DS enriched the target region harbouring stripe and leaf rust resistance genes. Stripe rust resistance locus, temporarily designated as YrAc, mapped at the distal most end of 5DS linked with a group of four colocated SSRs and two resistance gene analogue (RGA)-STS markers at a distance of 5.3 cM. LrAc mapped at a distance of 9.0 cM from the YrAc and at 2.8 cM from RGA-STS marker Ta5DS_2737450, YrAc and LrAc appear to be the candidate genes for marker-assisted enrichment of the wheat gene pool for rust resistance.     

A new genus and three new species of cockroaches (Blattaria: Dictyoptera) from Africa

A new genus Princisaria belonging to family Blaberidae is described from Africa. A key to the African genera of the subfamily Laxatinae is given. Three new species, P. carvalhoi, P. ugandana and P. curta are described.     

沿海拔梯度的表型可塑性影响银胶菊叶甲的取食效率和发育(英文)

【目的】本研究旨在弄清楚生态气候因子是否影响尼泊尔银胶菊Parthenium hysterophorus盛产区中银胶菊叶甲Zygogramma bicolorata成虫后代的形态学测量参数和基础生物学。【方法】 从尼泊尔Kathmandu (24℃, 海拔1 400 m, 温带气候), Chitwan (25℃, 海拔415 m, 热带或亚热带气候)和Mahendranagar (34℃, 海拔229 m, 湿润 亚热带气候)地区采集银胶菊叶甲成虫,在最适室内条件下评估各生态气候区中其F₁代4龄幼虫和雌成虫的取食特征。我们假定在自由取食和最适非生物条件下饲养的后代将不会受到食物和气温的间接影响,不管亲本属于哪一生态气候区,后代利用食物的能力一致。【结果】然而,我们发现,尽管在最适条件下饲养,银胶菊叶甲后代的体型和取食特征与其亲本相似。体型大的亲本(来自Kathmandu地区),其后代体型也大,但是其食物利用效率比体型小的亲本(来自Chitwan 和Mahendranagar地区)所产后代小。这3个生态气候区中,与幼虫相比正在发育的雌成虫均表现出体重增加而食物利用效率降低。【结论】这些发现说明,食物和最适非生物条件的间接影响可能不影响银胶菊叶甲后代的表型可塑性,后代的体型和取食特征与亲本相似。发生的可遗传的变化可能是由于种内的遗传多样性。我们期望这些发现有助于理解气候变化背景下银胶菊叶甲成虫的表型可塑性、分布格局和取食行为。     

Streptomycin- and Penicillin-induced Inhibition of Growth and Pigment Production in Blue-green Algae and Production of Strains of Anacystis nidulans Resistant to these Antibiotics

Relatively low concentrations of streptomycin inhibited thegrowth of Anacystis nidulans and Anabaena variabilis. The productionof chlorophyll, carotenoid, and phycocyanin pigments in thesealgae was significantly but reversibly inhibited by streptomycin.Strains of Anacystis nidulans that are resistant to streptomycinand penicillin were produced by serially subculturing the algain gradually increasing concentrations of the respective antibiotic.These strains seem stable. Evidence which suggests that theresistant strains originate primarily by mutation is presented.     

Natural enemies of Toxoptera aurantii (Boy.) (Homoptera: Aphididae) on cocoa in Ghana

Natural enemies of the black citrus aphid, Toxoptera aurantii (Boy.), on cocoa in Ghana are identified. Biology of some of the natural enemies is followed. Behaviour of the coccinellid and syrphid predators is studied in detail. Effectiveness of the predators in reducing the aphid populations is discussed.     

Witch Hunts, Herbal Healing, and Discourses of Indigenous Ecodevelopment in North India: Theory and Method in the Anthropology of Environmentality

ABSTRACT  In this article, we examine the environmental thought and practice of indigenous peoples living in and around a wildlife sanctuary in North India. Analysis reveals that those religious specialists (such as shamans) who possess knowledge of herbal healing are more committed than other villagers to preventing or mitigating the overharvesting of natural resources. To explain these results, reference is made to a specific juncture of native traditions and modern conditions and in particular to an intersection of local economies with global discourses of "ecodevelopment." Drawing on theories and methods from political ecology and cultural psychology, we present a framework for testing the extent that local actors—in this case, shamanic and herbalist healers—are differently positioned to resist or accommodate state and parastate structures of "environmentality" than are other villagers.