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The effects of atrazine on cotyledon cultures of Capsicum annuum (L.) cv. G 4 were investigated with a view of establishing a system for in vitro selection of resistant mutants. At low levels of herbicide produced little growth inhibition, some chlorophyll loss occurred associated with the production of albino shoots. At 20 mg l )1 atrazine bleaching was more pronounced and was accompanied by the development of necrotic spots; however, efficient bleaching was associated with severe suppression of growth. Mutagenized cotyledon explants resulted in production of herbicide-resistant plants on medium containing selective levels of sucrose (0.5%) and atrazine (20 mg l )1 ). Differential morphogenetic responses were observed when the levels of sucrose (0.5-5%) were altered. Shoot regeneration was maximum in 2% sucrose and the regenerating ability decreased with a further increase in sucrose concentration (3-5%). However, lowering of sucrose concentration from 2 to 0.5% caused complete bleaching of explants and permitted the selection of herbicide-resistant plants. Complete atrazine-resistant plantlets were obtained after rooting of regenerated green shoots on rooting medium containing 10 mg l )1 atrazine, 1.0 mg l )1 IAA and 0.5% sucrose. Leafsegment assay of differentiated plants revealed that all regenerants were resistant to the atrazine. Reciprocal crosses between atrazine-resistant and -sensitive plants showed a non-Mendelian transmission of resistance trait.

Chickpea (Cicer arietinum L.) is a major nutritional source cultivated worldwide. Chickpea is vulnerable to several abiotic and biotic stresses, including different types of soil-borne pathogens like Fusarium oxysporum f. sp. ciceri, which causes root rot disease and severely affects productivity. The putative transgenic plants were obtained with the Radish defensin (Rs-AFP2) gene through Agrobacterium tumefaciens mediated transformation using the embryo axis explants. Transgenes were con rmed in 18 putative transgenic plants with PCR-speci c primers for nptII and Rs-AFP2 genes. Twelve transgenic plants were established successfully under greenhouse conditions. The T0 plants were allowed for selfpollination and obtained T1 seeds. The T1 plants were selected for Fusarium wilt assay using Fusarium oxysporum f. sp. ciceri. The T1 plants showed different resistance levels, from moderate to high levels. The control plants (wild-type) exhibited severe wilt symptoms after Fusarium infection.

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