The plants of Euonymus have insecticidal activity. Euonymus chloranthoides Yang is an endangered plant endemic to
Chongqing. The population of this plant has been fragmented seriously at present. Six populations at Beibei in Chongqing were selected to study the reproductive value. With the decline of population size, the reproductive value and total reproductive value of life history increase, which indicated population invests more to reproduction when population size declined. Banzigou population was the smallest one in six populations studied, its reproductive value was lowest, which means that the population’s ability of reproduction regulation was destroyed because of too small population size. There was a antagonism relationship between population reproduction and growth, the individual longevity of small population was shorter than that of big population because the individual invests more on reproduction. In total, habitat fragmentation could do harm to reproduction regulation ability of small populations. |