Inheritance and expression analyses of cry1Ab gene in transgenic pigeonpea tolerant to Maruca pod borer

Abstract

Development of transgenic crops with stable gene inheritance and expression over generations is important for effective deployment at field level. In present study, T1 plants of pigeonpea cultivars AL15 and AL201 were evaluated for the presence and expression of cry1Ab gene and protection against Maruca pod borer. Cry1Ab protein in transgene carrying T1 plants ranged from 0.72 to 0.87 µg g-1 flower tissue. In vitro insect bioassay demonstrated up to 49.17 and 53.80% loss in larval body weight after four days of infesting T1 transgenic flowers and pods, respectively. Further, no adults emerged from the pupae of larvae fed on transgenic plants 15-537 and 201-344. All T2 progeny plants of 15-537 exhibited cry1Ab presence; likewise, all T3 progeny plants derived from homozygous T2 plant (15-537-5) displayed presence and expression of transgene, thus establishing stable transgene integration in T1 plants, followed by its stable inheritance and expression in T2 and T3 generations.