| Abstract: | The coincidence rates were more than 96% among the instar-weighted average of bioassays in the lab, the percentage of resistance to Km in the field and the percentage of plants containing Bt gene. So, the performance of resistance to Km in the field can be used to represent the transgenic Bt gene for selecting the resistance to bollworm. The instarweighted averages were 30.585, 24.182, 16.615, 10.601, 10.123, 7.440 and 7.215 for the CO, P1, M1, M2, MP1, P2 and MP2 populations, respectively. The variance analysis indicated that the instar-weighted average in CO was greatly significantly higher than that in all other populations, i.e., the performance of resistance to bollworm in CO was highly significantly lower than all other populations. And the resistance in P1 was greatly lower than that of M1, M2, MP1, P2 and MP2, and M1 greatly lower than that of M2,MP1, P2 and MP2. There were no significant differences among M2, MP1, P2 and MP2. Within the populations of the first cycle selection, MP1 and M1 were greatly significantly higher than P1, and MP1 significantly higher than M1. The populations of the second cycle selection were significantly higher than their initial population M1, but no significantdifference among them. The boll size, seed index, the percent of the first harvest yield,fiber length, strength and elongation of the resistant plants to bollwormwere significantly lower than that of sensitive plants to bollworm. And the yield of seed and lint cotton of the resistant plant to bollworm were lower than that of the sensitive to bollworm, but no significant difference between them. The boll numbers per plant, lint percent and micronaire of the resistant plants to bollworm were significantly higher than that of the sensitive plant to bollworm. |
