亚热带中山人工草地鸭茅种群及其分蘖丛数量性状的相关分析

根据单位面积和独立分蘖丛的调查与测定,分析了亚热带中山人工草地鸭茅种群及其分蘖丛的数量特征。结果表明,在开花至乳熟期,种子田鸭茅种群的分蘖丛密度已经超过了环境容纳量,但分蘖密度尚未达到环境容纳量。引种栽培试验地的鸭茅种群丛蘖数、丛生殖蘖数、丛营养蘖数与丛径之间,及其生产量与丛径和丛蘖数之间均呈极显著正相关。随着丛蘖数的增加,死亡蘖数呈Logistic曲线增长,死亡率呈直线增长。抽穗率随着丛径和丛蘖数的增加均呈直线下降。

A Correlation Analysis of Tillering Characteristics of Dactylis glomerata in Subtropical Sown Pastures

The quantitative tillering characteristics of Dactylis glomerata were investigated in the subtropical sown pastures at mountain slopes of a medium altitude, with measurements made on the bases of unit land area and individual tiller tufts. It was shown that during the period from flowering to milk-ripe phase the density of tiller tufts of D. glomerata in seed-producing plots reached at a level beyond the carrying capacity allowed by the environmental conditions, while the number of tillers in individual tufts remained within the capacity. As for the tiller tufts in the plots for introduction experiments, significant positive correlations were observed respectively between the diameter of tiller tufts and the numbers of individual tillers, reproductive tillers and vegetative tillers contained in a tuft, and also between the forage yield and the diameter of and the number of tillers in a tuft. With an increase in the number of tillers of a tuft the number of dead tillers increased with a pattern of the Logistic curve, while the percentage of dead tillers increased in a linear form. The percentage of earing tillers showed a negative linear relationship with the tuft diameter and the number of tillers in a tuft.