摘要
将2个对UV-B敏感性不同的绿豆品种‘秦豆-20’和‘中绿-1’幼苗放在培养室内,进行0.4W/m^2 UV-B辐射和0.4%NaCl胁迫的单独或复合处理,研究了NaCl胁迫对UV-B辐射诱导的DNA伤害和修复的影响。结果显示:在NaCl胁迫下,(1)在光下抗UV-B的品种‘中绿-1’的环丁烷嘧啶二聚体(CPD)累积量降低,而敏感品种‘秦豆-20’的CPD累积量未发生变化;(2)两品种CPD形成量均比无NaCl胁迫时低;(3)抗UV-B品种DNA的光、暗修复能力均比无NaCl胁迫时高:(4)而敏感品种DNA的光修复能力比无NaCl胁迫时低、暗修复能力未发生变化。另外,CPD形成量与紫外吸收物含量间具有明显的负相关性。说明NaCl胁迫不仅影响2个绿豆品种幼苗的CPD形成量,而且影响DNA的光、暗修复能力,进而导致了CPD累积量发生变化,由此影响了幼苗的UV-B敏感性。结果也暗示CPD形成量的变化是由于紫外吸收物质含量的不同所导致的。
In two mung bean cultivars （Phaseolus raditus L. cv. ＇Qindou-20＇ and ＇Zhonglti-l＇） with different sen- sitivities to U-V-B grown in growth chamber under supple- mental or no supplemental UV-B radiation （0.4 W/m2） with or without 0.4% NaC1, the effects of NaC1 stress on UV-B-induced DNA damage and repair were studied. The results showed that, under NaC1 stress, （i） CPD accumu- lation was lower in the tolerant cultivar ‘Zhonglti-l＇ but was the same in the sensitive cultivar ‘Qindou-20＇, （ii） CPD formation in both cultivars was weakened, （iii） the photorepair and dark repair capacity were higher in the tolerant cultivar and （iv） the photorepair was weakened and dark repair capacity did not change in the sensitive cultivar. There was a negative correlation between sus- ceptibility of CPD formation and levels of UV-absorb- ing compounds. These results demonstrate that NaC1 stress can affect not only the susceptibility to CPD formation, but also the capacities for photorepair and dark repair of DNA, which together result in the change in UV-B-induced CPD accumulation and thereby that in sensitivity of plant to UV-B. The results also suggest that the differences in susceptibilities to CPD formation are due to the differences in levels of UV-absorbing compounds.
出处
《植物生理与分子生物学学报》
CAS
CSCD
北大核心
2007年第5期441-448,共8页
Journal Of Plant Physiology and Molecular Biology
基金
国家自然科学基金项目(Nos.30370269,30670366)
陕西省自然科学研究计划项目(No.2006C_113)资助。~~
作者简介
通讯作者（E-mail：hejml965@yahoo，com．cn；Tel：029-85310266）。
