Serine proteinase inhibitors (IP's) are proteins found naturally in a wide range of plants with a significant role in the natural defense system of plants against herbivores. The question addressed in the present study involves assessing the ability of the serine proteinase inhibitor in combating nematode infestation. The present study involves engineering a plant serine proteinase inhibitor (pin2) gene into T. durum PDW215 by Agrobacterium-mediated transformation to combat cereal cyst nematode (Heterodera avenae) infestation. Putative T(0) transformants were screened and positive segregating lines analysed further for the study of the stable integration, expression and segregation of the genes. PCR, Southern analysis along with bar gene expression studies corroborate the stable integration pattern of the respective genes. The transformation efficiency is 3%, while the frequency of escapes was 35.71%. chi(2) analysis reveals the stable integration and segregation of the genes in both the T(1) and T(2) progeny lines. The PIN2 systemic expression confers satisfactory nematode resistance. The correlation analysis suggests that at p < 0.05 level of significance the relative proteinase inhibitor (PI) values show a direct positive correlation vis-à-vis plant height, plant seed weight and also the seed number.

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Bacillus thuringiensis Berliner, a gram positive aerobic bacterium, produces parasporal crystal (Cry) toxins that are highly specific and effective against insect species. During the course of isolation of native strains, B. thuringiensis AUG-5 was found the most effective with a wide range of activity against lepidopterans. Hence, different media were evaluated for its growth and development. Increase in concentration of the Luria Bertani [(LB), composed of casein, yeast extract and sodium chloride in 2:1:2 w/w)] medium in the fermentation broth from 1 to 2% increased colony forming unit (CFU), spore and also Cry1Ac and Cry2Ab toxin content. However, further increase of LB concentration to 3% adversely affected bacterial growth and development. Addition of 1% Wesson salt in 1% LB broth significantly increased spore, CFU counts, and also that of Cry1Ac but not of Cry2Ab. Spore and CFU counts in media were positively correlated and cell mass negatively correlated with Cry1Ac and Cry2Ab contents. Of all media substituting LB with agro products, medium consisting of 2% wheat flour, 2% soybean meal and 1% Wesson salt could be considered as an alternative to LB medium to achieve economy of largescale production costs. Spore-crystal complexes of Medium II and III were most toxic to the neonates of cotton bollworm, Helicoverpa armigera and tobacco caterpillar, Spodoptera litura at 10 µg/g, and differed significantly from those of Medium LB-2X and LB-3X and Cry2Ab2. Cry1Ac was most toxic to H. armigera at 1 µg/g and less toxic to S. litura than Cry2Ab.