水深变化对刺苦草冬芽形成的影响研究

The Effects of Water Level Fluctuation on the Winter Bud Formation of Submerged Macrophyte Vallisneria spinulosa

为弄清水深的变化对苦草冬芽形成的影响情况,在苦草的生长季节和繁殖体形成季节变化水位,设计实验研究苦草如何以无性繁殖的方式应对水位胁迫变化.研究结果表明：在刺苦草生长期内,冬芽母体大小和水位变化都显著影响冬芽的形成.在生长期内刺苦草形成的冬芽数量少,水位越低,形成的冬芽数量越少且更小,形成的冬芽平均数量为12~28个;在刺苦草繁殖期内,水位胁迫会加速刺苦草营养的转化,形成更多的冬芽,显著高于在生长期水位波动时的冬芽数,且不受冬芽母体大小的影响,此阶段形成的冬芽平均数量为45~83个.这些结论说明在植物生长季节维持相对稳定的水位生境有利于植物种群的延续,繁殖期水位的波动有利于水生植物无性繁殖体的形成.

To clarify out the effects of water depth change on the winter bud formation of submerged macrophyte Vallisneria spinulosa,the research is undertaken to reveal how the submerged macrophyte Vallisneria spinulosa deal with the stress of water-level fluctuation by the asexual reproduction mode both in the growing season and in the breedting season.The results showed the winter bud formation in Vallisneria spinulosa was significantly affected by water level fluctuation and mother body of winter buds in the growing season,and was much less in the number and weight of Vallisneria spinulosa.It was measured that the average number of winter bud changed in the range from 12 to 28.The stress of water level fluctuation in the breeding season accelerated transformation of nutrition of V.spinulosa to produce more winter buds.The study revealed that the number of winter buds was significantly more in the breeding season than in the growing season and the average number of winter bud changed in the range from 45 to 83 in this season.Those conclusions has proved that water levels remained relatively stable to be in favour for the growth of V.spinulosa during the growing season,while water level fluctuation was positive for the winter buds of V.spinulosa in breeding season.