北缘普通野生稻实验种群动态研究Ⅰ——克隆生长动态

Study of the Experimental Populations of Common Wild Rice (Oryza rufipogon) from Its Northernmost Distribution Ⅰ——Vegetative Growth Dynamic

以江西东乡普通野生稻北缘种群为材料,在当地构建了实验小种群,通过连续的定位跟踪、测定,对普通野生稻种群在各种生境条件下的克隆生长动态进行了长期实验研究.结果表明:(1)不同起始密度水平对普通野生稻生长有影响.较低的起始密度下,无性繁殖率较高,到20枝/m2时无性生长率降低到一个平衡水平,后不再有明显变化;而较高起始密度的种群,其每月的密度、综合生长量始终较高.(2)轻度放牧对普通野生稻的分蘖株数和综合生长量有一定的抑制作用,但是对无性繁殖率却有一定的刺激作用.(3)长期生长于深水对东乡普通野生稻北缘种群的生长具有抑制作用.

The northernmost populations of common wild rice (Oryza rufipogon Griff.) in Dongxiang, Jiangxi Province were used to construct small experimental populations. The population dynamics of vegetative growth of the wild rice under different ecological conditions were studied. The results showed that the initial density had an important effect on the growth of the wild rice; low population density (under 20 branch/m2)resulted in a high clonal reproductive rate, but populations with a high initial density showed good vegetative growth; grazing and cutting inhibited ramet growth of the wild rice, but stimulated the increasing of the clonal reproductive rate under certain extend. In addition, longterm inundation also inhibited ramets growth of the wild rice.