The mulberry silkworm, Bombyx mori (L.), is a model organism of lepidopteran insects with high economic importance. The viral diseases of the silkworm caused by Bombyx mori nucleopolyhedrovirus (BmNPV) and Bombyx mori bidensovirus (BmBDV) inflict huge economic losses and significantly impact the sericulture industry of India and other countries. To understand the distribution of Indian isolates of the BmNPV and to investigate their genetic composition, an in-depth population structure analysis was conducted using comprehensive and newly developed genomic analysis methods. The seven new Indian BmNPV isolates from Anantapur, Dehradun, Ghumarwin, Jammu, Kashmir, Mysore and Salem grouped in the BmNPV clade, and are most closely related to Autographa californica multiple nucleopolyhedrovirus and Rachiplusia ou multiple nucleopolyhedrovirus on the basis of gene sequencing and phylogenetic analyses of the partial polh, lef-8 and lef-9 gene fragments. The whole genome sequencing of three Indian BmNPV isolates from Mysore (-My), Jammu (-Ja) and Dehradun (-De) was conducted, and intra-isolate genetic variability was analyzed on the basis of variable SNP positions and the frequencies of alternative nucleotides. The results revealed that the BmNPV-De and BmNPV-Ja isolates are highly similar in their genotypic composition, whereas the population structure of BmNPV-My appeared rather pure and homogenous, with almost no or few genetic variations. The BmNPV-De and BmNPV-Ja samples further contained a significant amount of BmBDV belonging to the Bidnaviridae family. We elucidated the genotype composition within Indian BmNPV and BmBDV isolates, and the results presented have broad implications for our understanding of the genetic diversity and evolution of BmNPV and co-occurring BmBDV isolates.

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Asexual reproduction occurs widely in plants and animals, particularly in insects. Aphid species usually reproduce by cyclic parthenogenesis, but many species include obligate asexual lineages. We recently showed that the leaf-curl plum aphid, Brachycaudus helichrysi, actually encompasses two lineages, B. helichrysi H1 and H2. Ecological data suggest that these lineages have different life cycles. We conducted a large population genetics study, based on 14 microsatellite loci, to infer their respective life cycles and investigate their population structure and geographical distribution. Brachycaudus helichrysi H1 displayed the genetic signature of cyclical parthenogenesis, using plum trees as primary hosts for sexual reproduction, as classically described for B. helichrysi. This global survey showed that the Central Asian population of H1 was clearly differentiated from American-European populations. By contrast, B. helichrysi H2 displayed the typical signature of obligate asexual reproduction. H2 encompassed at least eight highly successful genotypes or superclones. This lack of ability to undergo sexual reproduction was confirmed for one of the superclones by sex induction experiments. We found only one B. helichrysi H2 population that underwent sexual reproduction, which was collected from peach trees, in Northern India. Our results confirm that H1 and H2 have different life cycles. Brachycaudus helichrysi H1 is clearly heteroecious using plum trees as primary hosts, while B. helichrysi H2 encompasses several anholocyclic lineages, and some heteroecious populations that until now have only been found associated with peach trees as primary hosts. We discuss implications of these findings for the pest status of B. helichrysi lineages.

Background A study was carried out to classify municipal solid waste (MSW) compost produced in Delhi, India for their marketability and use in different area with respect to physico-chemical properties, fertilizing and heavy metal polluting potentials. Results The pH of the compost was slightly alkaline (8.4 ± 0.02) and C:N ratio (9.46 ± 0.91) was low as compared to Fertilizer Control Order (FCO) Standard, Government of India, 1985. Sample analysis was carried out using standard methods. The concentrations of some selected heavy metals, e.g., Zn, Cd and Ni were within the permissible limit of FCO standard. However, the concentrations of Cu, Pb and Cr exceeded (66.7 %) the permissible limit of FCO standard. Further, the compost was characterized to know the fertilizing potential and its potential to contaminate the soil. Fertilizing index (FI) was calculated from the values of TOC, TN, TP, TK and C:N ratio and clean index (CI) was also calculated using heavy metal concentrations. FI value of compost was varied from 4.47 to 4.60, whereas CI value of compost was varied from 2.33 to 2.87, respectively. Conclusions The study results indicated that majority of MSW compost produced in Delhi failed to achieve quality control guidelines of FCO standard. The compost has fertilizing potential, however, certain risk to the environment.Hence, the prepared compost in Delhi was not suitable for its intended purpose. Post-treatment of compost is required to improve the quality of compost, which can be utilized for agricultural purposes.

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Functional response of all instars, adult males and females of the ladybird Coccinella septempunctata L. was studied against two species of aphids, namely Lipaphis erysimi (Kalt.) and Brevicoryne brassicae L., infesting mustard and cabbage crops, respectively. The predatory stages of C. septempunctata exhibited a type II response on both the prey species. The attack rate was highest (0.0192) with the lowest handling time (7.9 min) when the adult female consumed L. erysimi. There was a significant difference in the predicted values of consumption of L. erysimi by fourth instars, adult males and females compared with those of B. brassicae, indicating that the former prey is preferred over the latter one. The adult females prey upon significantly more numbers of aphids than the adult males.

The demand of vegetable crops is increasing day by day due to changes in consumption patterns, so the need of the hour is to develop technologies that enhance the vegetable production at a rapid rate. Plant Tissue culture is one such remarkable biotechnological tool that has its application in vegetable propagation and improvement, disease elimination, herbicide resistance, salinity tolerance, incorporation of high nutrient content, genetically improved plants and conservation of endangered plant species and in the near future usage of this technology is going to increase further manifold. It is used for production of disease free quality planting material and development of varieties through direct regeneration, anther/ovule culture, somatic embryogenesis etc. or for creation of new variation (organogenesis via callus formation, soma-clonal variation and in vitro mutagenesis). In spite of being a very important and viable non-conventional biotechnological tool, high cost of production of seedlings in vitro remains a major impediment in popularization of this technology. High cost of producing seedlings is due to availability of limited resources, high recurrent costs of consumables for media and lack of awareness, which limits its application only to a few institutions and rich farmers especially in developing countries. Therefore, in order to make this technology a successful and viable option for the farmers, future thrust must be on cost reduction of in vitro seedlings. The components of tissue culture technology such as culture media components, glassware, lighting and water for media preparation can be replaced with low cost alternatives to reduce the overall cost of tissue culture. The usage of alternatives for gelling agent’s like isabgol (potato, tomato, cassava, turmeric, ginger), sago (potato, tomato, turmeric, ginger) cassava starch (potato, cassava, sweet potato) barley starch, phytagel etc. and for carbon sources like table sugar (potato, turmeric, ginger), jaggery, sugarcane juice, cube sugar (bittergord), brown sugar etc have already been documented worldwide. The present paper reviews the work done by researchers around the globe in developing various low cost alternative technologies with focus on vegetable crops.

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