北缘普通野生稻实验种群动态研究Ⅱ——生殖生长动态

Study of the Experimental Populations of Common Wild Rice ( Oryza rufipogon ) from Its Northernmost DistributionⅡ—Reproductive Growth Dynamics

以江西东乡和湖南茶陵普通野生稻北缘种群为材料 ,在繁育期对当地构建的普通野生稻种群实验小种群进行了连续的调查和测定 ,研究北缘普通野生稻在各种实验条件下有性生殖的生长动态 ,结果表明 :(1)不同起始密度下普通野生稻各小种群的有性繁殖量有一定差异 ,较低的起始密度抽穗率低 ,而较高起始密度的种群有性繁殖的总量相对较高 ,到 4 0枝 /m2 时抽穗率增长到一个稳定水平 .(2 )放牧条件对普通野生稻的有性繁殖总量影响不大 ;而刈割则对普通野生稻的有性繁殖具有明显的抑制作用 ,在较轻度的切割条件下虽未使普通野生稻个体趋于灭绝 ,但对抽穗等有性繁殖指标来说则是灾难性的 .(3)长期生长于过高的水深对北缘普通野生稻的有性繁殖也具有抑制作用 .

The northernmost populations of common wild rice ( Oryza rufipogon Griff.) of Dongxiang, Jiangxi province were used to construct small experimental populations, and population dynamics of sexual reproduction of the wild rice under different ecological conditions were studied. The results showed that the initial density had an important effect on the sexual reproductive of wild rice. For example, low population density resulted in low tassel rate, and the populations were increased to a stable tassel rate until 40 branch/m^(2), so the population with high initial density showed good sexual reproductive growth. Grazing had little effect on the sexual reproduction of wild rice in this research, but cutting can severely inhibited sexual reproductive growth of the wild rice. In addition, long-term inundation was harmful to experimental populations, and deep water also inhibited sexual reproduction of the wild rice.