空心莲子草营养繁殖特性研究

STUDY ON THE VEGETATIVE PROPAGATION CHARACTER OF Altern anthera philoxeroides

对 3类不同生境中茂密和稀疏两种生长状态空心莲子草的营养器官作了调查 ,结果表明 ,空心莲子草的地下部和地上部营养器官的生物量与其生活的环境有显著的相关性 ,生境含水量的高低与根冠比大小有明显的负相关 ;进一步研究了空心莲子草营养器官的繁殖能力 ,表明 1节根状茎、匍匐茎或 0 .2cm肉质状根片段均可以成活 ,1节根状茎的繁殖系数约为 1.5。另外 ,通过模拟干旱、湿润、水生三种生境条件 ,测定并比较了空心莲子草地上部分枝数、节数、长度和叶数在 5～ 9月间的动态变化 ,结果表明 :空心莲子草的地上部具有很强的蔓延能力 ;在湿润即土壤含水量适中的生境中空心莲子草生长速度比在干旱或水生环境中快、长势更好 ,而且同期的生物量各个指标前者也比后两者大。

The vegetative organs of Alternanthera philoxeroid es(Mart.) Griseb. in thick and thin growing states under three different habit ats was investigated. The results showed that the biomass of aerial part and sub terraneous part had a remarkable relationship with the environments in which the y grew, and there was obviously a negative correlation between the water content of different habitats and the root/shoot ratio of alligatorweed. Further studyi ng, the propagation capacity of the vegetative organs of alligatorweed showed th at a segment of stolon, rhizome with one node or 0.2-cm-long fleshy root could survive under an appropriate condition. And the propagation coefficient of rhiz ome was about 1.5. The experiment under three different niches showed that the a erial part of alligatorweed had a strong spreading ability; alligatorweed grew f aster and its biomass increased more in marsh than in dry land and pool, and add itionally, all the biomass indices studied in marsh were bigger than those in th e other niches in the same period.