关键词: 土壤盐分, 棉蕾, Bt棉, 氮代谢, Bt基因, 杀虫蛋白

Abstract: Habitat fragmentation results in isolated and patched small populations. At present, however, little is known about population structure and regeneration mode of rare and endangered tree species in different patches. The static life table of Emmenopterys henryi population was compiled based on population life table and theory of survival analysis by applying age class structure represented by DBH class and smoothing out technique. Meanwhile, sizeclass structure and sprouting ratio of this species in five patches were also examined. The results showed that there was a fluctuation in the structure of E. henryi populations across the five patches. Overall, the survival curve of the population tended to follow the type of Deevey Ⅱ, and the individuals at juvenile stage were abundant. The mortality rate and disappearance rate in the lifespan had similar variation trend, with the peaks in the 1st and 5th age class periods. The survival rate of the population decreased monotonically, whereas the cumulative mortality rate increased monotonically. Nevertheless, the two rates began to be flat from the 5th age class. Additionally, sprouting ratio and Magini index differed markedly across the five patches. Despite longterm persistence by virtue of sprouting regeneration, some patches of small populations have been so seriously threatened that the local populations are on the edge of extinction due to human disturbance.

Key words: Bt protein, soil salinity, Bt gene, flower bud, nitrogen metabolism., Bt cotton