稳定碳同位素测定水分利用效率的可行性分析—以决明子为例

Abstract

Stable carbon isotope composition( δ13C value) was one of the effective methods for measuring the plant water use efficiency( WUE),and was already applied in many plants. At present,the study on estimation of the WUE of Cassia obtusifolia L.. by δ13C was a few. In order to prove the reliability of δ13C on measuring WUE for Cassia obtusifolia L.,δ13C、stable carbon isotope discrimination( Δ13C) 、WUE and the relationship among them are measured in different organs( root,steam,leaf) and different growth stages by pot experiment and δ13C. The results showed that,the δ13C value and Δ13C of roots were highest,the next were stems,leaves were minimum,there were significant level in the δ13C value and Δ13C in roots in different growth stages,positive relationship were found between the δ13C value and WUE in stems and leaves,negative relationship were found between the Δ13C and WUE in stems and leaves. It showed significant positive correlation level among WUE( Potted method) and WUEL、WUES、WUER( Carbon isotope method),related coefficient were 0.86、0. 82、0.80 respectively,those showed carbon isotope technology was reliable to determine the WUE of Cassia obtusifolia L..