羊草种群种子生产的初步研究

 本文报道了国产优良牧草——羊草，在不同人为干扰的环境条件下，种群种子生产数量性状变化的若干规律。种群密度是成穗率的限制因素之一，在平均为604.7株／m2中等密度的数年割草场上，成穗率随密度增加呈幂函数y=dx-b形式下降，而在平均为1604.9株／m2高密度的长期连续割草场上，成穗率随密度增加呈直线y=a-bx形式下降。种子发芽率与千粒重呈显著正相关(r＝0.9768**)。放牧对成穗有不良影响，但对籽粒的干物质积累过程有一定的促进作用。长期连续割草对种群生殖生长的整个过程均不利，停刈后，自然恢复的速度缓慢。

A PRELIMINARY STUDY ON SEED PRODUCTION OF ANEUROLEPIDIUM CHNENSE POPULATION

Aneurolepidium chinense is an excellent forage grass in China. Theseed production of its population in different environmental conditionswith artificial interference and some regularities in the quantitative ch-ange of its seed production is reported in this paper. The density is oneof the limitation factors of the earing percentage of its population. Theearing percentage decreases with the increase in density, assuming a po-wer function y=dx~(-b) in a short-term mowing plot of 604.7 147.6 stemsper square metre, which is medium density, and a linearfunction y=a-bx in a long-term mowing plot of 1640.9 104.6 stems persquare metre, which is great density. The germinating percentage has aclose positive correlation with 1000-seed weight. Grazing decreases theearing percentage but promotes the process of dry-matter accumulationin the seed. Long-term repeated mowing is harmful to the process ofthe entire sexual development of the population and even after mowingis stopped, the natural recovery of seed production is slow.