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Pigeon pea is an important legume. Yield losses due to insect pests are enormous in the cultivation of this crop. Expression of cry proteins has led to increased resistance to pests in several crops. We report in this paper, expression of a chimeric cry1AcF (encoding cry1Ac and cry1F domains) gene in transgenic pigeon pea and its resistance towards Helicoverpa armigera. PCR, Southern hybridization, RT‐PCR and Western analysis confirmed stable integration and expression of the cry1AcF gene in pigeon pea transgenics. When screened for efficacy of the transformants for resistance against H. armigera, the transgenics showed not only high mortality of the larva but could also resist the damage caused by the larvae. Analysis for the stable integration, expression and efficacy of the transgenics resulted in the identification of four T3 plants arising from two T1 backgrounds as highly promising. The results demonstrate potentiality of the chimeric cry1AcF gene in developing H. armigera‐resistant pigeon pea.

The objective of the present study was to develop a probiotic of canine-origin for its potential application in pet nutrition. Accordingly, 32 lactic acid bacteria (LAB) strains were isolated from faeces of dogs, out of which 9 strains were short-listed for further in vitro testing based on the aggregation time and cell surface hydrophobicity. The results of acid-, bile- and phenol-tolerance tests indicated that out of the nine, isolate cPRO23 was having better resistance to these adverse conditions likely to be encountered in the gastrointestinal tract. The isolate also showed optimal enzymatic activities for amylase, lipase and protease. Further assessments also indicated its superiority in terms of co-aggregation and antagonistic activity against pathogenic strains of Salmonella typhimurium and Salmonella enteritidis. Subsequently, the isolate was identified through 16S rRNA sequencing and sequence homology, and designated as Lactobacillus johnsonii CPN23. The candidate probiotic was then evaluated in vivo using 15 adult Labrador dogs, divided into 3 groups, viz. CON (with no probiotics), dPRO (with Lactobacillus acidophilus NCDC 15 as a conventional dairy-origin probiotic) and cPRO (with L. johnsonii CPN23 as a canine-origin probiotic). Results of the 9-week study indicated that supplementation of cPRO improved (P < 0.05) the faecal concentration of acetate and butyrate with a concomitant reduction (P < 0.05) in faecal ammonia. The cell-mediated immune response, assessed as delayed-type hypersensitivity reaction to phytohaemagglutinin-P, was better (P < 0.05) in dogs fed cPRO as compared to the CON dogs. There were, however, no variations evident in the antibody response to sheep-erythrocytes among the three groups. It is concluded that the canine-origin L. johnsonii CPN23, in addition to possessing all the in vitro functional attributes of a candidate probiotic, also has the potential to be used as a probiotic in pet nutrition programs.

Flowering time is a major determinant of adaptation, fitness and yield in the allopolyploid species rapeseed (Brassica napus). Despite being a close relative to Arabidopsis thaliana, little is known about the timing of floral transition and the genes that govern this process. Winter, semi‐winter and spring type plants have important life history characteristics that differ in vernalization requirements for flowering and are important for growing rapeseed in different regions of the world. In this study, we investigated the timing of vernalization‐driven floral transition in winter rapeseed and the effect of photoperiod and developmental age on flowering time and vernalization responsiveness. Microscopy and whole transcriptome analyses at the shoot apical meristems of plants grown under controlled conditions showed that floral transition is initiated within few weeks of vernalization. Certain Bna.SOC1 and Bna.SPL5 homeologs were among the induced genes, suggesting that they are regulating the timing of cold‐induced floral transition. Moreover, the flowering response of plants with shorter pre‐vernalization period correlated with a delayed expression of Bna.SOC1 and Bna.SPL5 genes. In essence, this study presents a detailed analysis of vernalization‐driven floral transition and the aspects of juvenility and dormancy and their effect on flowering time in rapeseed.

No abstract

Large number of primary transgenic events were generated in groundnut by an Agrobacterium mediated, in planta transformation method to assess the efficacy of cry1AcF against the Spodoptera litura. generation demonstrated homozygous nature. This clearly proved that though there is considerable improvement in average mean % larval mortality in T 2 generation, the cry1AcF gene was effective against S. litura only to some extent.

Plant regeneration has been achieved from long-term cell suspension cultures established from leaf derived callus of tepary bean (Phaseolus acutifolius). The proportion of densely cytoplasmic cells in suspension culture increased when cultured in the L-6 medium with 54 μM NAA and 2 μM KN. Filtration of the cells at each of five consecutive subcultures resulted in the isolation of a plant regenerating cell line (TB 686), which is being maintained in L-6 medium with 4.5 μM 2,4-D and 2.3 μM zeatin. Differentiated green cell aggregates were obtained when cells from maintenance medium were transferred to the same medium with 10 μM BA. Embryo-like structures developed from these aggregates on L-6 medium with 2.3 μM zeatin, 0.69 μM GA3 and 1.5 μM NAA. Plantlets regenerated from these structures when they were cultured on L-6 medium with 7.0 μM NAA and 1.0 μM KN. Plant regeneration from the cell line remained relatively constant for 270 days. Regenerated plants were grown to maturity in the greenhouse.

Plant regeneration has been achieved routinely from established cell suspension culture lines of Vigna aconitifolia (moth bean), a highly drought tolerant grain legume. The cultures originated from three-week-old leaf callus. Several media including MS, B5, AA, SL, PCM, SH and L-6 were tested for their effects on cell growth. Maximum growth was observed in L-6 medium containing 44.5 μM 2,4-D. After 6 to 8 weeks the suspensions were filtered through 500, 250, 125 and 60 μm sieves, respectively, for four to five subcultures. An embryogenic cell line (VA-686) was obtained from the cell fraction collected below 250 μm. The VA-686 cell line is being maintained on L-6 medium with 4.5 μM 2,4-D and 2.3 μM Zeatin. Somatic embryogenesis was induced by transferring the cells to L-6 medium with 4.6 μM zeatin in which green cell clusters were produced. The somatic embryos developed from most of the cell clusters when plated on L-6 agar medium with 2.3 μM BA.Plantlets were obtained from the embryos on L-6 medium with 10.0 μM IBA. The regenerated plants were grown to maturity in the greenhouse.