Inheritance of cry1A(b) and snowdrop lectin gna genes in transgenic javanica rice progenies and bioassays for resistance to brown planthopper and yellow stem borer

摘要

Progenies of transgenic lines from Indonesian rice cultivar Rajaiele (Karang Agung) containing the ciylA(b) gene and gna were subjected to PCR, Southern, and western analyses and bioassay for yellow stem borer (YSB) and brown planthopper (BPH). Segregation of individual genes in the T_1 and T_2 generations of positive T_0 transgenic lines obtained through particle bombardment was determined using PCR analysis on the plant population that has one or both genes. Results showed that 7 of 12 T_1 transgenic lines containing gna and 5 of 7 T_1 lines containing cry1A(b) segregated in a Mendelian fashion, whereas, in one transgenic line, genes were not inherited in the second generation. Homozygous plants could be selected in the third generation (T_2) in some transgenic lines using PCR analysis, The bioassay for YSB on positive progenies of four T_1 transgenic ctylA(b) lines on the stems showed 0 to 100% insect mortality rates, although in all transgenic lines YSB instar growth was suppressed. The bioassay against BPH on the segregated T_1 population was scored based on the percentage of plant mortality using BPH type 1. Results showed partial resistance in some lines (plant mortality ranged from 52.5% to 83.5%, compared with 100% of nontransgenic Rajaiele and TN-1 sensitive controls. The bioassay on the T_2 generation using BPH biotype 2 of Indonesia showed no enhanced resistance in transgenic plants.