真盐生植物梭梭和囊果碱蓬幼苗耐干旱能力的研究

本文以沙生植物白梭梭幼苗为对照,研究了盐生植物梭梭和囊果碱蓬幼苗的耐干旱脱水能力,通过比较干旱时间对三者幼苗干旱后存活率的影响,评价其耐脱水能力,并对复水后根部细胞的受损情况进行了研究。结果表明:根长为 12 cm白梭梭幼苗经过7,14,21和28 d干旱后,存活率没有显著性差异,但是梭梭和囊果碱蓬随着干旱时间的延长,存活率发生显著性地降低,囊果碱蓬幼苗干旱28 d后全部死亡并发生降解;白梭梭幼苗的耐干旱能力比较强,干旱28 d后复水根部死亡细胞和受伤的细胞比较少,而梭梭死亡和受损程度明显比白梭梭高;300 mmol /L NaCl溶液处理,梭梭的根尖发生弯曲,根尖大部分死亡。研究表明,白梭梭、梭梭和囊果碱蓬属于“同型叶绿素型”植物,在光照下干旱叶绿体不会被降解,其幼苗在干旱和复水过程中能够适应干旱环境。

Study of resistance to dehydration in Haloxylon ammodendron and Suaeda physo-phora seedlings

The previous research has been concentrated on the dehydration resistance of the seedlings in the two halophytes:Haloxylon ammodendron and Suaeda physophora .Comparing with the psammophyte Haloxylon persicum,both the seedling survival rate and the root damage after the desiccation were investigated,the re-sults showed that:No significant difference was found in the survival rates of H .persicum among the 7,14, 21 and 28 days desiccation treatments,however,the survival rates of H .ammodendron and S .physophora has been significantly decreased with the desiccated duration,in which the seedlings of S .physophora were all died in the 28 days desiccation treatment.The seedling root of H .persicum was rarely damaged by the 28 days desiccation treatments,which was better than that in H .ammodendron,in the 300 mmol/L NaCl treatment, the root tip of the H .ammodendron seedlings were all bended and died.It was showed that H .persicum,H . ammodendron and S .physophora were all “homoiochlorophyllous”resurrection plants,they would not de-grade their chlorophyll during the desiccation time,and could survive fast when the water supplied again, which was an important adapt strategy to the extremely drought environment.