摘要
为了进一步明确冷季型草坪草形态、水分生理和碳分配模式对干旱及复水处理的反应,本试验以草地早熟禾草的3个栽培种:新歌来德、午夜和奖金为材料,进行人工模拟干旱处理21 d,然后再恢复浇水21 d。期间测定了草坪质量、叶片相对含水量(RWC)、总的非结构性碳水化合物(TNC)含量及14C同化物在根、茎、叶的分配率。试验结果表明,干旱胁迫造成3个品种的草坪质量和RWC明显下降,变化幅度因品种和处理时间不同而存在差异;复水后,草坪质量和RWC不同程度地得到恢复,其中奖金表现出较强的恢复能力。干旱胁迫初期,3个品种根部14C分配率明显增加,干旱14 d时,3个品种14C分配模式为:根>茎>叶。随着干旱胁迫的进行,14C由根部向茎和叶片转移,其茎和叶片中14C分配率明显升高。复水21 d后,3个品种中14C分配率模式为:茎>叶>根;干旱胁迫期间,3个品种的叶片、茎和根之间TNC积累量一直发生变化,干旱胁迫21 d时,3个品种TNC含量在根、茎、叶中的积累模式为:叶>茎>根。复水后,3个品种根、茎、叶中TNC积累量较干旱胁迫21 d时各自对应器官中TNC积累量有不同程度下降,但TNC在根、茎、叶中的积累模式与干旱胁迫期间保持一样。试验结果表明,在干旱和复水处理中碳同化物在植物体内不同器官不同分配率及碳水化合物在植物体内不同器官中积累是草坪草对干旱胁迫及复水处理的一种生理调节反应,将为今后研究草坪草在其他逆境胁迫下的抗性提供了一定的科学参考。
The morphology,water physiology,and carbon allocation responses of cool-season turfgrass to drought stress and re-watering treatments were studied.Three cultivars（Prize,Nuglade,and Midnight） of Kentucky bluegrass（Poa pratensis）,were tested under drought and re-watering treatments to determine the changes in turf quality,leaf relative water content（RWC）,total nonstructural carbohydrate（TNC） content and 14C allocation in different organs.Drought stress caused a significant decline in turf quality and leaf RWC,which varied with cultivar and treatment time.After re-watering,turf quality and leaf RWC recovered to different degrees,especially in Prize.At the early stages during drought stress,14C allocation to the roots increased significantly for all cultivars.After 14 d drought stress,14C allocation to different organs in the three cultivars was rootsshootsleaves.With prolonged drought stress,some 14C in the roots moved into the shoots and leaves,resulting in a marked increase of 14C allocation to the shoots and leaves.After 21 d re-watering,14C allocation in the three cultivars was shootsleavesroots.During the drought stress,TNC accumulation in the roots,shoots,and leaves of the three cultivars continually changed and was in the sequence leavesshootsroots.After re-watering,the TNC content in the leaves,shoots,and roots of all three cultivars was lower than that under drought stress,but still in the same order.This suggests that the allocation of carbon assimilates and their accumulation in different organs of turfgrasses were a physiological adaptation response to drought and re-watering treatments and provides a scientific basis for further investigating the resistance of turfgrasses to other adverse environments.
出处
《草业学报》
CSCD
北大核心
2010年第2期31-38,共8页
Acta Prataculturae Sinica
基金
甘肃省自然科学基金(0803RJZG033)
甘肃省教育厅科研项目(080903)
农业部草地农业生态系统学重点开放实验室项目资助
