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Morphologically normal and fertile transgenic plants of mungbean with two transgenes, bar and alpha-amylase inhibitor, have been developed for the first time. Cotyledonary node explants were transformed by cocultivation with Agrobacterium tumefaciens strain EHA105 harboring a binary vector pKSB that carried bialaphos resistance (bar) gene and Phaseolus vulgaris alpha-amylase inhibitor-1 (alphaAI-1) gene. Green transformed shoots were regenerated and rooted on medium containing phosphinothricin (PPT). Preculture and wounding of the explants, presence of acetosyringone and PPT-based selection of transformants played significant role in enhancing transformation frequency. Presence and expression of the bar gene in primary transformants was evidenced by PCR-Southern analysis and PPT leaf paint assay, respectively. Integration of the Phaseolus vulgaris alpha-amylase inhibitor gene was confirmed by Southern blot analysis. PCR analysis revealed inheritance of both the transgenes in most of the T(1) lines. Tolerance to herbicide was evidenced from seed germination test and chlorophenol red assay in T(1) plants. Transgenic plants could be recovered after 8-10 weeks of cocultivation with Agrobacterium. An overall transformation frequency of 1.51% was achieved.

The specific activities and transcript levels of glycolytic enzymes were examined in shoots of chickpea (Cicer arietinum L.) cultivars, Pusa362 (drought tolerant) and SBD377 (drought sensitive), subjected to water-deficit stress 30 days after sowing. Water-deficit stress resulted in decrease in relative water content, chlorophyll content, plant dry weight, and NADP/NADPH ratio and increase in NAD/NADH ratio in both the cultivars. A successive decline in the specific activities of fructose-1,6-bisphosphate aldolase (aldolase), 3-phosphoglycerate kinase (PGK), and NADP-glyceraldehyde-3-phosphate dehydrogenase (NADP-GAPDH) and elevation in the specific activities of phosphoglycerate mutase (PGM) and triosephosphate isomerase (TPI) was observed in both the cultivars under stress as compared to their respective control plants. The specific activities of hexokinase, fructose-6-phosphate kinase (PFK), and NAD-GAPDH were least affected. The transcript levels of PGK and NADP-GAPDH decreased and that of glucose-6-phosphate isomerase (GPI), PGM, and PFK increased in response to water-deficit stress while water-deficit stress had no effect on the steady-state transcript levels of hexokinase, aldolase, TPI, and NAD-GAPDH. The results suggest that under water-deficit stress, the activities and transcript levels of most of the glycolytic enzymes are not significantly affected, except the increased activity and transcript level of PGM and decreased activities and transcript levels of PGK and NADP-GAPDH. Further, the glycolytic enzymes do not show much variation between the tolerant and sensitive cultivars under water deficit.

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The efficiency of Vigna mungo L. Hepper transformation was significantly increased from an average of 1% to 6.5% by using shoot apices excised from embryonic axes precultured on 10 microM benzyl-6-aminopurine (BAP) for 3 days and wounded prior to inoculation in Agrobacterium tumefaciens strain EHA105 carrying the binary vector pCAMBIA2301, which contains a neomycin phosphotransferase gene (nptII) and a beta-glucuronidase (GUS) gene (gusA) interrupted by an intron. The transformed green shoots that were selected and rooted on medium containing kanamycin, and which tested positive for nptII gene by polymerase chain reaction, were established in soil to collect seeds. GUS activity was detected in whole T(0) shoots and T(1) seedlings. All T(0) plants were morphologically normal, fertile and the majority of them transmitted transgenes in a 3:1 ratio to their progenies. Southern analysis of T(1) plants showed integration of nptII into the plant genome.