A New Strain of Entomopathogenic Bacillus of the Tea Pest,Eterusia magnifica （Butl.） （Zyganiidae： Lepidoptera） from Darjeeling Foothill Region of India

An entomopathogenic strain of Bacillus sp. was isolated from diseased red slug caterpillars of the leaf-feediug pest of tea, Eterusia magnifica, from the Darjeeling foothill region. Analysis of the bacterimn based on polyphasic approach such as growth phase, biochemical tests, whole body＂ protein, crystal protein profiles along with bioassay （i.e. LC50 and LT50 values） established it as a different strain but close to Bacillus thuringiensis kurstaki （Btk）, the commercial microbial pesticides of lepidopterans. Among biochemical parameters differences were noted between the new strain and Btk in ONPG, lysine decarboxylase, omithin decarboxylase, urease, nitrate reduction, V-P and glucose utilization tests. PAGE analysis of the whole body protein for the new strain recorded a 34 kDa band which was absent in Btk （used as reference）. Crystal protein profile of the newly isolated bacterial strain showed 53 and 49 kDa bands whereas in Btk only 52 kDa band was evident. Although the LC50 values of the new strain and Btk were close, their LT50 values were much different, the new strain showing a lower value than Btk. In light of the above differences and in absence of any report of entomopathogenic bacterial strain of E. magnifica, the isolated strain of Bacillus appeared to be new to science and hence was designated as RS01. The new strain opens up the possibility of its futttre use as microbial pesticide after standardizing its formulation and checking its safety aspects.     

Effect of Host Plants on Development,Fecundity and Enzyme Activity of Spodoptera exigua （Hübner）（Lepidoptera：Noctuidae）

The beet armyworm,Spodoptera exigua (Lepidoptera:Noctuidae),is an economically important pest of crops worldwide,attacking plants from over 20 families including trans-continental agricultural cotton,corn and citrus crops.In this study,performance and subsequent enzyme activity of beet armyworm reared on host plants from five families were investigated.Significant differences were found in development,fecundity and enzyme activity on different host plants.Survival rate was the highest (42.8％) on asparagus lettuce (Lactuca sativar var.asparagina) and the lowest (17.0％) on sweet pepper (Capsicum annuum).Larval duration was the shortest on asparagus lettuce (12.0 d),and was 43.4％ longer on sweet peppers (21.2 d).The activity of acetylcholine esterase (AChE) and carboxylesterase (CarE) in 3rd instar larvae,and soluble carbohydrate and crude protein contents in different host plants were determined.AChE activity was the highest in the larvae feeding on Chinese cabbage (Brassica rapa),but declined by nearly 60％ on maize (Zea mays) seedlings.The ratio of soluble carbohydrate content to crude protein content in host plants was found to have a positive effect on oviposition and a negative correlation with larval duration and life time (from larval to adult stages) of the insect.     

Rice Grain Damage by Combination and Sequence Infestations by the Rice Leaffolder,Cnaphalocrocis medinalis Guenee （Lepidoptera：Pyralidae）, and the White-Backed Rice Planthopper,Sogatella furcifera Horváth （Hemiptera：Delphacidae）

The rice leaffolder （RLF）, Cnaphalocrocis medinalis Guenée （Lepidoptera：Pyralidae）, and the white-backed rice planthopper （WBPH）, Sogatella furcifera Horváth （Hemiptera： Delphacidae）, are major insect pests in China and several other Asian countries. These two pests commonly occur simultaneously or in a temporal sequence. Thus, the investigation of the effect of complex infestations or temporal sequence infestations by these pests on rice yield has a practical signiifcance for the control of these pests. The present study comprised experiments with the following four different variables in potted rice at the tillering stage：single pest species infestation, complex infestation, complete combination infestation and temporal sequence infestation （C. medinalis infestation prior to S. furcifera and S. furcifera infestation prior to C. medinalis）. The results showed that the four infestations resulted in a signiifcant decrease in 1 000-grain weight （1 000GW） and rate of yield loss （RYL） but an increase in blighted grain rate （BGR）, with a signiifcant positive correlation with the infestation density. However, the inlfuences of the complex infestation, complete combination infestation or sequence infestation on the 1 000GW, BGR and RYL were greater than those of the single pest species infestations but did not have addition effects, i.e., the effects of the complex infestation and combination infestation or sequence infestation on the 1 000GW, BGR and RYL were less than the additive effects of the two single pest species infestations at the same densities. In the condition of the same total infestation pressure, no signiifcant differences in the 1 000GW, BGR and RYL were found between C. medinalis infestation prior to S. furcifera and S. furcifera infestation prior to C. medinalis as well as between the sequence infestation and the complex infestation.     

Phylogeny of Limenitidinae Butterflies （Lepidoptera： Nymphalidae） Inferred from Mitochondrial Cytochrome Oxidase I Gene Sequences

The phylogenetic analyses of the subfamily Limenitidinae are performed based on 1471 bp of mtDNA cytochrome oxidase subunit I (C01) gene sequence data which were obtained from 21 individuals spanning 9 genera, along with those of 17species obtained from GenBank, using Apatura iris, Aglais urticae, and Polyura dolon as outgroup species. Although the transitions at the third codon positions of the COI data set were highly saturated, they were still retained for analysis as they contain the majority of the phylogenetic information, and thus, the maximum pasimony (MP) under different weighting schemes and maximum likelihood (ML) trees were reconstructed in this study. The results showed that within this subfamily, the results based on the COI gene sequences are approximately identical to the traditional classification results. However, the clustering of Lexias pardalis and Tanaecia julii within the genus Euthalia as well as the clustering of Phaedyma aspasia within the genus Neptis with weak support are different from that of the current classification scheme made by Chinese scholars. The genus Limenitis is splited into two subelusters in the trees constructed by using MP and ML methods. These results support one of the strongest hypotheses for the tribe relationships within Limenitidinae.     

Spatio-temporal relationships of Clania miniscula （Lepidoptera： Psychidae） and garden spider （Araneae： Araneidae） in sasanqua orchard

Spatio-temporal relationship of the phytophagons Clania miniscula （Butler） and garden spiders was examined through analysis of their niche and distribution as they occur in sasanqua orchard in Southern Anhui, China from June 2003 to May 2004. The dynamic relationships between Clania minuscula and garden spiders were seasonal in time and space. Spatio-temporal niche breadth was high for the two groups, ranging from 0.57 to 0.98; niche overlap was also high between the two groups from 0.76 to 0.96 during the seasons of June 2003 to May 2004. Geostatistical results indicated that Clania minuscula and garden spiders were aggregated during the emergence periods. The pest Clania minuscula was spatially dependent to a range from 33.48 to 46.84 m while spatial dependence from 30.93 to 51.11 m for garden spiders. The correlation analysis of distribution maps further illustrate the distribution of garden spiders always coincided with that of Clania minuscula. These results showed spatio-temporal synchrony of Clania minuscula and garden spiders at different periods. Adequate knowledge of spatio-temporal correlation between Clania minuscula and garden spiders contributed to provide information for biocontrol at different periods in sasanqua orchard.     

Performance and Enzyme Activity of Beet Armyworm Spodoptera exigua （Hübner） （Lepidoptera：Noctuidae） Under Various Nutritional Conditions

We explored the influence of the artificial diets with different protein and glucose contents on larval development, development, fecundity and population growth index of beet armyworm increased with increased nutritional content in the artificial diets; however, when the yeast to cellulose content ratio reached 46.8:53.2, the fecundity and population growth had reached a maximum and additional protein did not yield additional growth. Additionally, 3rd instar beet armyworm larvae fed on different artificial diets had increased enzymatic activities of acetylcholinesterase (ACHE) with the increased nutritional content, but carboxylesterase (CarE) activities did not significantly change under variation in the nutritional content.     

Lethal and Sublethal Effects of Leaves Extracts from Native and Exotic Plants in Southern Brazil against Spodoptera frugiperda （Lepidoptera： Noctuidae） Caterpillars

The caterpillar Spodopterafrugiperda is an important pest of several crops, due to the damage it causes and the difficulty of its control. The method of controlling these pests is through chemical insecticides, which cause adverse effects to the biotic and abiotic environment. The selection of new insecticides that meet the requirements of efficacy, safety, selectivity and those are economically viable, is highlighting the study of mechanisms of plant defense. The present study aimed to verify the insecticide effect of 27 plants in three different types of plants extracts： aqueous, decoction and polypeptide on S. frugiperda. Three plants were chosen for performing sublethal effects bioassays： two plants with the highest corrected mortality （E. pulcherrima and R. simsii） and the other plant （Maytenus ilicifolia （espinheira santa）） with corrected mortality similar to control. In preliminaries bioassays, 25 plants showed corrected mortality less than 50%, according to Abbott＇s formula. R. simsii （azalea） and E. pulcherrima （billed parrot） showed 51% and 68% of corrected mortality, respectively. Only R. simsii aqueous and the three extracts of E. pulcherrima differ significantly from control （P 〈 0.05）. The aqueous extracts and decoction of R. simsii and polypeptide extract of E. pulcherrima reduced the larval period of S. frugiperda, different from control （P 〈 0.05）. The polypeptide extract of R. simsii reduced the pupal period of the target insect. The extracts obtained by decoction, aqueous and polypeptide of E. pulcherrima extracts and decoction of polypeptides and R. simsii affected the fertility and fecundity of S. frugiperda. For the other parameters, there is no significant difference when compared with the control. The results of this study suggest that the extracts obtained by decoction, aqueous and polypeptide of E. pulcherrima and R. simsii can be used to control S. frugiperda. However, the successful search, product starting from extracts of plants depends on the availability of plant and the entire assembly around the detection of bioactive products, in addition to the active ingredients of the chemical synthesis and elucidation of the target site insecticide molecule.     

Development of Sequence Characterized Amplified Region （SCAR） Primers for the Detection of Resistance to Sporisorium reiliana in Maize

Head smut of maize （Zea mays L.）, which was caused by Sporisorium reiliana, occurred in most of the maize growing areas of the world. The purpose of this study was to develop SCAR markers for map-based cloning of resistance genes and MAS. Two sets of BC3 progenies, one （BC3Q） derived from the cross Qi319 （resistance）×Huangzao 4 （susceptible）, the other （BC3M） from Mol7 （resistance）× Huangzao 4 （susceptible）, were generated. Huangzao 4 was the recurrent parent in both progenies. A combination of BSA （bulked segregant analysis） with AFLP （amplified fragment length polymorphism） method was applied to map the genes involving the resistance to S. reiliana, and corresponding resistant and susceptible bulks and their parental lines were used for screening polymorphic AFLP primer pairs. One fragment of PI3M61-152 was converted into SCAR （sequence charactered amplified fragment） marker S130. The marker was mapped at chromosome bin 2.09, the interval of a major QTL region previously reported to contribute to S. reiliana resistance. Furthermore, S130 was highly and facilitate map-based cloni associated with resistance to S. reiliana, and could be useful for marker-assisted selection ng of resistance genes.     

The Susceptibilities of Oxya chinensis （Orthoptera： Acridoidea） to Malathion and Comparison of the Esterase Properties from Three Collected Populations in Tianjin Area,China

The susceptibilities of Oxya chinensis to malathion were studied in three populations collected from outskirt of Tianjin, China, using bioassays and biochemical analysis. Populations were chosen to represent different exposure to insecticides： BDG （Beidagang; low exposure）, BD （Baodi; high exposure previously but low exposure now）, and JN （Jinnan; high exposure）. The results showed that the LD50 values of BD and JN populations were 3.95- and 12.02-fold and 3.64- and 10.07- fold higher than that of BDG population in females and males, respectively. The LD50 values in females were higher than those in males. The results of biochemical analysis indicated that the esterase （EST） activities in JN population were higher than those in BD and BDG populations. They showed that when α-NA, α-NB, and α-NA were used as substrates, females＇ EST activities of JN population were 1.11-, 1.30-, and 1.14-fold and 1.39-, 1.59-, and 1.54-fold higher than those of BD and BDG populations, respectively. When α-NA, α-NB, and β-NA were used as substrates, males＇ EST activities of JN population were 1.13-, 1.12-, and 1,00-fold and 1.20-, 1.14-, and 1.07-fold higher than those of BD and BDG populations, respectively. The results also showed that the specific activities of the females were higher than those of the males in the BD and JN populations, whereas the specific activities of the males were higher than those of the females in the BDG population. The results of bioassay were consistent with those of biochemical analysis. Thus, it was inferred that the elevated ESTs activities might play an important role in conferring the differences of susceptibility of O. chinensis to malathion in the three collected populations. Enzyme kinetic studies indicated that the Km and Vmax values were different among the three collected populations and between the females and the males. The observed changes in the kinetic parameters might be explained by differential expression patterns of isozymes so that the insect esterases have different affinities and maximum velocities toward the same substrate.     

Changes in Soil Biota Resulting from Growth of the Invasive Weed,Ambrosia artemisiifolia L.（Compositae）, Enhance Its Success and Reduce Growth of Co-Occurring Plants

Exotic plant invasion presents a serious threat to native ecosystem structure and function. Little is known about the role of soil microbial communities in facilitating or resisting the spread of invasive plants into native communities. The purpose of this research is to understand how the invasive annual plant Ambrosia artemisiifolia L. facilitates its competition capacity through changing the structure and function of soil microbial communities. The soil characteristics of different areas invaded by A. artemisiifolia were examined. Greenhouse experiments were designed to assess the effect of A. artemisiifolia invasion-induced changes of soil biota on co-occurring plant growth, and on the interactions between A. artemisiifolia and three co-occurring plant species. The results showed that the soil organic C content was the highest in heavily invaded sites, the lowest in native plant sites, and intermediate in newly invaded sites. Soil available N, P and K concentrations in heavily invaded site were 2.4, 1.9 and 1.7 times higher than those in native plant soil, respectively. Soil pH decreased as A. artemisiifolia invasion intensity increased, and was lower in invaded sites（heavily invaded and newly invaded） than in native plant sites. The soil microbial community structure was clearly separated in the three types of sites, and A. artemisiifolia invasion increased anaerobe, sulfate-reducing bacteria and actinomycete abundance. Soil biota of invaded sites inhibits growth of co-occurring plants（Galinsoga parvifloraCav., Medicago sativa L. and Setaria plicata（Lam.） T. Cooke.） compared to soil biota from un-invaded sites, but facilitates A. artemisiifolia growth and competition with co-occurring plants. A. artemisiifolia biomass was 50-130% greater when competing with three co-occurring plants, compared to single-species competition only（invasion by A. artemisiifolia alone）, in heavily invaded soil. Results of the present study indicated that A. artemisiifolia invasion alters the soil microbial communit