干旱区研究2017，Vol.34Issue(3)：638-647,10.DOI:10.13866/j.azr.2017.03.21
梭梭根系的水分再分配特征对其生理和形态的影响
Root Internal Hydraulic Redistribution and Its Effects on the Physiological Form and Plant Growth of Haloxylon ammodendron
摘要
Abstract
Water redistribution within root system can mitigate root drought stress in dry season.In this study, a split-root pot cultivation experiment was conducted to test the effects of root hydraulic redistribution of Haloxylon ammodendron, and the root dynamics was observed by minirhizotron method.Considering the occurrence of hydraulic redistribution in the low evaporative demand, a series of growth and water physiological and root dynamic characteristics of plant in wet and dry split rhizospheres of pot were measured under three treatments:control (C):24-hour light + supplemental water (LW);and 24-hour light only (L).The results are as follows:① The leaf water potential of plant in control at dawn and on midday was higher in compared to that in light treatment, and the root water potential of dry soil zone (the upper tube) in control and light and water addition treatment was also higher than that in light treatment.This result indicated that water potential of roots in dry soil zone in control partly recovered at dawn on next day due to the hydraulic redistribution at night;② The transpiration and the maximum net photosynthetic rates under the control and light and water addition treatments were higher than those in light treatment, which suggested that the root internal hydraulic redistribution protected the deterioration of plant photosynthetic physiological activities under draught stress;③ The aboveground biomass under light treatment was lower in compared to that in the control and light and water addition treatments, and the root dry weight of the whole plant,root dry weight in dry soil zone and specific root length (SRL) were significantly different among the treatments and in a rank of LW ＞ C ＞ L.In sum, the effects of water hydraulic redistribution on water potential and photosynthetic characteristics of H.ammodendron were observed, which proved that the hydraulic redistribution could protect the roots of desert shrub in topsoil under temporal soil draught and maintain a healthy physiological activity.关键词
梭梭(Haloxylon ammodendron)/根系/土壤含水量/同化枝水势/水分再分配/蒸腾速率Key words
Haloxylon ammodendron/root/soil moisture content/assimilating branch/water potential/hydraulic redistribution/transpiration rate引用本文复制引用
朱丽,黄刚,唐立松,李彦,张永梅,盛建东..梭梭根系的水分再分配特征对其生理和形态的影响[J].干旱区研究,2017,34(3):638-647,10.基金项目
国家自然科学基金项目(31370010,31570455)资助 （31370010,31570455）
