Diversity of parasitoids and predators in the sole cropped and intercropped, border cropped, and hedgerow cropped fields of guava (sole cropped and intercropped with cowpea), mulberry (sole cropped and border cropped with castor), and sapota (sole cropped and intercropped with clusterbean) were documented in two villages Naukalpalya and P Rampura of Kanakapura district in Karnataka, India, during 2016-2017. The parasitoids and predators were collected using yellow pan traps and sweep nets. The variations in the diversity, species richness, and evenness between two cropping systems are discussed in this paper. Diversity indices were worked out. Predators belonging to the families viz., Coccinellidae, Carabidae, Chrysopidae, Syrphidae, and Pentatomidae were recorded. The adult parasitoids belonging to the families Trichogrammatidae, Braconidae, Encyrtidae, and Ichneumonidae were recorded. Shannon-Weiner index, Margalef's richness index, and evenness index found to be higher in the inter/border/hedgerow cropped fields compared to the sole cropped ecosystems. The abundance of the adult stage of the predators and parasitoids of the inter/border/hedgerow crops was found to be higher. The results of the study confirmed the role of crop diversification as a tool to enhance the functional biodiversity of parasitoids and predators for an efficient biological control program.
A field trial was conducted in a farmer's field by integrating biocontrol agents, a multiple insecticide tolerant strain (MITs), Trichogramma chilonis and formulation of Bacillus thuringiensis (NBAIR BtG4) with reduced insecticidal spray as a biocontrol-based IPM compared to insecticidal application as a farmer's practice, for the management of the diamondback moth (DBM), Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae) infesting cabbage. Six T. chilonis releases of 100,000 parasitized eggs ha − 1 were applied. Along with parasitoid release, a liquid formulation of B. thuringiensis (2%) was applied after third and fifth releases of T. chilonis. The number of P. xylostella larvae were significantly reduced in the field treated with biocontrol-based IPM as compared to farmer's practice after 30 and 45 days after treatment. After the 45 days, the holes on cabbage leaves were 2.2/plant in the field treated with biocontrol, opposed to 8.0 holes per plant were recorded in the farmer's practice filed. Only 7% of cabbage head damage was recorded in the field treated with biocontrol, whereas, in farmer's practice field, those were 32.2%. The cost-benefit analysis showed that integrating these biological control agents along with a reduced number of insecticidal sprays could reduce DBM population and percent head damage with an eventual increase in the yield.
The small carpenter bee, Ceratina binghami (Xylocopinae:Apidae) is an important pollinator of many agricultural and horticultural crops. The nests constructed by the bee in the pruned pithy stems of Caesalpinia pulcherrima were collected to study its biology under laboratory conditions. The bee constructs its nest in the pithy stems of different plants by chewing over the pith layer. The bee is oligolectic in habit and make pollen balls and provision its broods in the cells with an interesting guarding behavior in the nest. The nests consisted of egg, larvae, prepupae, pupae and adult stages. Life cycle of the bee was completed in 41.67±3.12 days. Pupal stage consisted of different colors of eye pigmentation. Foraging activity of the bee started during morning hours approximately between 6.45 to 7.15 am and ended during the late evening hours of 4.50 to 5.15 pm. The nest architecture of the bee was studied and presented. The nesting behavior and short life cycle of C. binghami in pithy stems of C. pulcherrima helps in the in-situ conservation and utilization of the bee species in the pollination of agricultural crops.
A PCR based method for detection of viral DNA in nucleopolyhedrovirus of three lepidopterans, Spodoptera litura, Amsacta albistriga and Helicoverpa armigera, was developed by employing the late expression factor-8 (lef-8) gene of three NPV using specific primers. The amplicons of 689, 699 and 665 bp were amplified, respectively, and the nucleotide sequences were submitted to GenBank and the accession numbers were obtained. The sequences of lef-8 gene of S. litura NPV and H. armigera NPV matched with those of their respective references in the GenBank database, thereby confirming their identity, however, the sequence of A. albistriga NPV was the first sequence submitted to the GenBank database. The sequence similarity analysis between the three lef-8 gene of NPV sequenced in the present study revealed that there was no significant similarity between them, however A. albistriga NPV and S. litura NPV were found to be closely related. CLUSTAL alignment of the sequences generated revealed general relatedness among NPVs lef-8 gene. The study confirmed that lef-8 gene can be used for quick and correct discriminatory identification of insect viruses.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.