The comparison of species diversity and abundance of insect natural enemies in the domesticated species of cotton using the yellow pan trap method.

India is the world's largest cotton producer and the only country that grows all four cultivated cotton species. There have been very few studies on the diversity and abundance of natural enemies of cotton insect pests in these cultivated cotton species. Therefore, the current study (2016-2018) was conducted to assess the diversity and abundance of natural enemies that cultivated cotton species harbour. Phule Dhanwantari, Suraj, Suvin, RCH-2, and DCH-32 were the five genotypes used in the study, each with a distinct genetic background. Using the adiv 2.0.1 and vegan R packages, we identified significant differences in natural enemies in terms of species diversity, richness, evenness, and abundance. Analysis of Similarity (ANOSIM) and Non-metric Multidimensional Scaling (NMDS) indicated substantial differences in the natural enemy community structure among the examined genotypes. A total of 17,279 natural enemies were collected and identified across genotypes from seven predatory families and five parasitoid families. The percentage share of these natural enemy families across genotypes and years, in descending order, is Coccinellidae (28.23%) < Tachinidae (19.23%) < Braconidae (12.68%) < Chrysopidae (11.65%) < Chalcididae (9.41%) < Aphelinidae (6.33%) < Pentatomidae (3.29%) < Ichneumonidae (2.37%) < Syrphidae (2.33%) < Vespidae (1.81%) < Asilidae (1.79%) < Geocoridae (0.89%). Coccinellidae, Tachinidae, Braconidae, Chrysopidae, Chalcididae, and Aphelinidae are the six major families that account for more than 85% of all recorded natural enemies. These six families have a higher percentage share in Phule Dhanwantary (90%) compared to the other genotypes. The conservation and better utilization of these natural enemies are crucial for the ecological and safe management of insect pests in the cotton ecosystem.

Molecular and in Silico Characterization of Achaea janata Granulovirus Granulin Gene.

Achaea janata granulovirus (AcjaGV), an insect virus belonging to Baculoviridae, infects semilooper, a widely distributed defoliating pest on castor beans (Ricinus communis L.) and several other plant hosts in India. The propagation and purification of the Hyderabad isolate AcjaGV were performed, granulin gene from this isolate was amplified, cloned and sequenced, and its homology with other known granulin genes was assessed. The 753-bp granulin ORF of AcjaGV encoded for a granulin protein of 250 amino acids with a molecular mass of 29.5 ± 0.7 kDa. This amino acid sequence exhibited significant homology with Spodoptera litura granulovirus (SpliGV) and other GVs infecting insects in the same Noctuidae family of Lepidoptera. Peptide analysis of granulin protein indicated close homology with that of SpliGV. Virtual RFLP patterns from in silico digestions of granulin gene of 18 granuloviruses mapped by 12 restriction enzymes were used for simulated digestions. Implications of the phylogenetic relationships of granulin nucleotide and deduced amino acid sequence are discussed. We have established the sequence identity of granulin gene of AcjaGV and characterized its protein product and the phylogenetic relationship with other known GVs. Our results indicate the presence of unique restriction sites for three restriction enzymes, and this can be used as a tool for identification of AcjaGV from various sources. This is the first report from the Indian subcontinent to describe the complete granulin gene of a GV isolated from A. janata.

Bioclimatic thresholds, thermal constants and survival of mealybug, Phenacoccus solenopsis (hemiptera: pseudococcidae) in response to constant temperatures on hibiscus.

Temperature-driven development and survival rates of the mealybug, Phenacoccussolenopsis Tinsley (Hemiptera: Pseudococcidae) were examined at nine constant temperatures (15, 20, 25, 27, 30, 32, 35 and 40°C) on hibiscus (Hibiscusrosa -sinensis L.). Crawlers successfully completed development to adult stage between 15 and 35°C, although their survival was affected at low temperatures. Two linear and four nonlinear models were fitted to describe developmental rates of P. solenopsis as a function of temperature, and for estimating thermal constants and bioclimatic thresholds (lower, optimum and upper temperature thresholds for development: Tmin, Topt and Tmax, respectively). Estimated thresholds between the two linear models were statistically similar. Ikemoto and Takai's linear model permitted testing the equivalence of lower developmental thresholds for life stages of P. solenopsis reared on two hosts, hibiscus and cotton. Thermal constants required for completion of cumulative development of female and male nymphs and for the whole generation were significantly lower on hibiscus (222.2, 237.0, 308.6 degree-days, respectively) compared to cotton. Three nonlinear models performed better in describing the developmental rate for immature instars and cumulative life stages of female and male and for generation based on goodness-of-fit criteria. The simplified ß type distribution function estimated Topt values closer to the observed maximum rates. Thermodynamic SSI model indicated no significant differences in the intrinsic optimum temperature estimates for different geographical populations of P. solenopsis. The estimated bioclimatic thresholds and the observed survival rates of P. solenopsis indicate the species to be high-temperature adaptive, and explained the field abundance of P. solenopsis on its host plants.