松嫩平原羊草种群生殖分蘖株的数量特征及其定量分析

在松嫩平原羊草籽实的乳熟-成熟期,对翻耙样地和封育样地的羊草生殖蘖进行取样调查.结果表明,在同一生境条件下,生殖蘖株高、穗序长、节间长、穗节数和生殖生长比率5个性状较均匀整齐,籽实数、结实率、小花数和小穗数的生态可塑性较大.生殖蘖高度与穗序长、节间长呈极显著正相关,与生殖生长比率呈显著或极显著负相关,穗序长与节间长、穗节数、小穗数和小花数均呈显著或极显著正相关,穗节数与小穗数和小花数、小穗数与小花数、籽实数与小花数和结实率均呈极显著正相关.羊草生殖蘖数量特征的生态可塑性及其相互间的定量关系,揭示了羊草生殖蘖个体生长、发育和生殖的协调发展规律.小花数随小穗数、籽实数随小花数和结实率在2个样地呈异速增长,是翻耙样地羊草生殖蘖籽实产量远大于封育样地的主要原因.

Quantitative analysis of reproductive tiller characteristics of Leymus chinensis populations on the Songnen Plain of China

In the milk-mature stage of grain,the reproductive tillers of L. chinensis populations were sampled and their quantitative characteristics investigated and analyzed for both ploughed and enclosed plots. The results showed that in the same habitat,the height,ear length,inter-node length,spike node number and ratio of reproductive growth (RRG) of reproductive tillers were quite uniform and in order,but the ecological plasticity was relatively large for grain number,seed-setting percentage,number of florets and number of spikelets. Tiller height was very significantly positively correlated to both ear length and inter-node length,but was significantly negatively correlated to RRG. Ear length was significantly positively correlated to inter-node length,spike node number,number of spikelets and number of florets. Significant positive correlations were also found between spike node number and both spikelet number and floret number,between spikelet and floret numbers,and between grain number and both floret number and seed-setting percentage. The ecological plasticity of characteristics of L. chinensis reproductive tillers and their quantitative correlations revealed the natural laws for the individual to regulate its growth,development and reproduction. The number of grains per reproductive tiller was much higher in the ploughing plot than in the enclosed plot,largely because the increase of floret number with spikelet number and the increase of grain number with both floret number and seed-setting percentage were relatively allometric in the two plots.