火烧对结缕草种群有性生殖的影响

研究火烧和未烧样地结缕草(Zoysia japonica)种群的有性生殖数量特征。结果表明:火烧极显著地增加了生殖枝密度,极显著地降低了花序种子数,但对千粒重没有显著影响,种子产量是未烧的1.85倍;火烧并未影响种子质量(千粒重)而是增加了种子数量(粒数)并提高其生育力;火烧未改变有性生殖数量性状(花序种子数,花序长,生殖生长比率,花序种子重和生殖分配)与生殖枝高度间的定量关系。

Effects of Fire on the Quantitative Characters of Sexual Reproduction of Zoysia japonica Population in Liaodong Peninsula, China

The effect of fire on the quantitative characters of sexual reproduction of Zoysia japonica population in Liaodong Peninsula was studied. The results show that burning of the Z.japonica grass before its bur-geoning in March could very significantly reduce the number of grain per spike(NGPS), but impressively raise the density of the reproductive tillers, while not influence the weight of 1000 grains (WTG). Thus, the grain yield in the burnt plot was 1.85 times higher than that in the non-burnt plot. Burning largely enhanced the fecundity of Z.japonica population not by increasing the weight per grain but by increasing the number of grain. The height of the reproductive tillers(HRT) was positively correlated to some quantitative characters of reproduction, such as number of grain per spike, spike length, and weight of grain per spike, but negatively correlated to ratio of spike to reproductive tiller length, and reproductive allocation.The quantitative rela-tionships between those quantitative characters and height of reproductive tillers were the same in the burnt and non-burnt plots.