持续干旱及复水对鱼腥草新品系W01-100生长和生理特性的影响

Influence of Progressive Drying and Rewatering on the Growth and Physiological Characters of Houttuynia cordata Thunb.New Line W01-100

目的研究干旱及复水处理对鱼腥草新品系W01-100生长和生理特性的影响。方法采用盆栽土壤中度干旱胁迫处理鱼腥草W01-100四叶植株苗30 d,然后复水30 d,并设置对照,测定鱼腥草各生长和光合特性指标,并检测抗氧化物酶活性和丙二醛含量动态变化。结果干旱胁迫条件下,鱼腥草新品系W01-100植株株高显著降低,茎显著变细,干物质量减少,净光合速率显著降低;随着胁迫时间延长,叶片抗氧化酶CAT、POD活性先升后降,叶中丙二醛含量逐渐上升。复水后,经干旱处理的鱼腥草W01-100各生长和光合特性指标、抗氧化物酶活性以及丙二醛含量与对照组差异均不显著。结论土壤干旱能显著抑制鱼腥草新品系的生长,鱼腥草新品系W01-100在一定中度干旱胁迫时间内具有适当抗旱性,但不能抵御长时间持续干旱胁迫。

Objective To study the influence of drought and rewatering on the growth and physiological traits of Houttuynia corda- ta Thunb. new line W01 - 100. Methods Growth and photosynthetic index of four - leaf - old plants were measured after the plants were subjected to water deficit and then rewatered each for 30 days, respectively. The changes of MDA content and the activ- ities of antioxidant enzymes were also assayed during water stress. Results The plants under water deficit grew shorter significant- ly,and with thinner stem, fewer biomass and lower net photosynthetic rate than the control. The activities of CAT and POD in- creased at first and then decreased, and MDA contents increased progressively with the stress time. There was no significant differ- ence between the drought treatment and the control on all indexes after rewatering. Conclusion Drought can significantly inhibit the growth of H. cordata new line W01 - 100. H. cordata new line has the ability of resisting the drought in a short period of drought stress but can not be tolerant to the long lasting drought stress.