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The dragonfly Sympetrum meridionale (Selys, 1841) (Odonata-Libellulidae) occurs throughout Asia Minor to Persia and Kashmir. The earlier Indian records of S. meridionale are from Yusimarg, 2286 m, and from below Gulmarg, 2438 m, Kashmir valley. Herein, the range extension and high altitudinal record of this species is reported from the Indus riverine, Leh, Ladakh Union territory of India at an elevation of 3500 m. A note on the habitat, which is entirely different from that of Kashmir valley, its originally known habitat, is provided. Study of museum specimens reveals the eastern most record of the species, from Sikkim and an additional new record from Srinagar. The species diagnosis including comparison of male genitalia, along with the need to validate the previous records from Rajasthan and further surveys along Himalaya and lower latitudes are discussed.

An insecticidal mannose binding lectin gene of Withania somnifera, WsMBP1 was constitutively expressed in tobacco plants. Instar-wise study on the response of Hyblaea puera larvae to the total protein extracted from transgenic tobacco was conducted and survivability percent was 33.33% and 55.55% in the first and the second instars, respectively. Minimum survivability of 22.22% was registered in the third instar. Further, two-fold reduction was observed in mean pre-pupal and pupal weight in the third instar larval populations fed with lectin protein compared to the control populations. The functional confirmation of the insecticidal activity of WsMBP1 established its potential as a novel gene resource for future transformation studies in developing teak genotypes tolerant to its leaf defoliator, H. puera.

Lectins are carbohydrate-binding proteins with wide array of functions including plant defense against pathogens and insect pests. In the present study, a putative mannose-binding lectin (WsMBP1) of 1124 bp was isolated from leaves of Withania somnifera. The gene was expressed in E. coli, and the recombinant WsMBP1 with a predicted molecular weight of 31 kDa was tested for its insecticidal properties against Hyblaea puera (Lepidoptera: Hyblaeidae) and Probergrothius sanguinolens (Hemiptera: Pyrrhocoridae). Delay in growth and metamorphosis, decreased larval body mass and increased mortality was recorded in recombinant WsMBP1-fed larvae. Histological studies on the midgut of lectin-treated insects showed disrupted and diffused secretory cells surrounding the gut lumen in larvae of H. puera and P. sanguinolens, implicating its role in disruption of the digestive process and nutrient assimilation in the studied insect pests. The present study indicates that WsMBP1 can act as a potential gene resource in future transformation programs for incorporating insect pest tolerance in susceptible plant genotypes.

Withania somnifera (L.) Dunal is a valued medicinal plant with pharmaceutical applications. The present study was undertaken to analyze the salicylic acid induced leaf transcriptome of W. somnifera. A total of 45.6 million reads were generated and the de novo assembly yielded 73,523 transcript contig with average transcript contig length of 1620 bp. A total of 71,062 transcripts were annotated and 53,424 of them were assigned GO terms. Mapping of transcript contigs to biological pathways revealed presence of 182 pathways. Seventeen genes representing 12 pathogenesis-related (PR) families were mined from the transcriptome data and their pattern of expression post 17 and 36 hours of salicylic acid treatment was documented. The analysis revealed significant up-regulation of all families of PR genes by 36 hours post treatment except WsPR10. The relative fold expression of transcripts ranged from 1 fold to 6,532 fold. The two families of peroxidases including the lignin-forming anionic peroxidase (WsL-PRX) and suberization-associated anionic peroxidase (WsS-PRX) recorded maximum expression of 377 fold and 6532 fold respectively, while the expression of WsPR10 was down-regulated by 14 fold. Additionally, the most stable reference gene for normalization of qRT-PCR data was also identified. The effect of SA on the accumulation of major secondary metabolites of W. somnifera including withanoside V, withaferin A and withanolide A was also analyzed and an increase in content of all the three metabolites were detected. This is the first report on expression patterns of PR genes during salicylic acid signaling in W. somnifera.