冬季干旱胁迫后复水对鼠茅草生理特性的影响

本文通过模拟试验研究了冬季干旱胁迫后复水对鼠茅草生理特性的影响,试验设置了干旱胁迫和正常水分处理,采用PVC管基质栽培鼠茅草,冬季干旱胁迫结束后复水采集鼠茅草样品,测定分析了鼠茅草干旱胁迫后复水及对照处理的鼠茅草叶片及根系的生理生化指标。结果表明,干旱胁迫后复水与正常水分处理相比,叶绿素a含量、总叶绿素含量、生物量、各级根长与根表面积显著降低,叶绿素b指标无显著差异。MDA、可溶性蛋白、电解质渗透率指标显著增加,这说明鼠茅草干旱胁迫复水后仍存在一定的胁迫,冬季干旱胁迫后复水对鼠茅草的生长有一定的抑制作用。试验还表明在不具备冬季灌溉条件下,冬季断水60 d后复水对鼠茅草的生长指标有一定的影响,但不危及生命,可适当断水,在开春后应及时灌溉,以提高光合作用,增加生物量。

The Effect of Rehydration after Winter Drought Stress on the Physiological Characteristics of Vulpia myuros C.Gmelin

In this paper,the effect of rehydration after winter drought stress on the growth physiological characteristics of Vulpia myuros C.Gmelin was studied by the simulating winter water deficit stress.The experiment set up two treatments with three replicates each as water deficit stress(DF)and traditional water treatment(WF).PVC pipes were used to simulating cultivate of Vulpia myuros C.Gmelin.After the grass experienced winter drought stress,rewater the grass(DF treatment),WF treatment were watered traditionally during the period.After rewaster periods,we collected Vulpia myuros C.Gmelin samples,measured the growth physiological characteristics of the grass.The results showed that even after rewater,the DF treatment still decreased the content of chlorophyll a and total chlorophyll,the biomass,root length and root surface area significantly.In addition,compared with WF treatment,DF treatment increased the electrolyte leakage rate,MDA content and soluble protein content significantly.Those results indicated that there was still a certain degree of stress after rewatering under DF treatment.Thus,we concluded that winter drought stress had a certain inhibitory effect on the growth index of Vulpia myuros C.Gmelin,but 60 days of drought stress had no life threatening to the grass,which means that orchard sod cultivation Vulpia myuros C.Gmelin can cut off irrigation in winter,but irrigation should be done in time after spring,to improve photosynthesis and promote the increase of grass biomass.