苇状羊茅控水处理后的补偿性生长

Compensatory growth of tall fescue following drought stress

采用盆栽试验研究了苇状羊茅 (FestucaarundinaceaSchreb .)拔节期控水处理及复水后的生长、干物质生产状况及其补偿性生长特性。结果表明 ,拔节期控水处理使植株的叶绿素含量和净同化率 (NAR)显著降低 ,株高、分蘖数、叶面积和植株干物质增长趋于停滞 ,但控水处理期间叶片和茎基部的可溶性碳水化合物 (WSC)含量呈上升趋势。复水后 ,生长迅速得到恢复 ,分蘖数增加 ,新叶生长显著加快 ,NAR和叶片WSC含量显著高于对照 ,但茎基部WSC显著下降。复水 8d后 ,处理与对照植株干物质重无显著差异 。

Growth,dry matter(DM)production and compensatory growth of tall fescue(Festuca arundinacea Schreb.cv.Fawn)were studied with a pot trial during drought treatment and after rewatering in elongating stage.The result showed that chlorophyll content and net assimilation rate(NAR)decreased and plant height,tillers,leaf area,and DM accumulation tended to stagnation by the drought stress,but concentration of water soluble carbohydrates(WSC)in leaf tissue and stem bases increased.The plants grew rapidly after rewatering.Tillering and leaf extension increased significantly,NAR and WSC in the leaf of treated plants were higher than those of control although WSC in stem bases showed a reversed result.Dry weight of aerial part of treated plants did not significantly differ from the control plants after 8 days of rewatering,i.e.,compensatory growth appeared by removing the drought stress.