干旱胁迫下四倍体刺槐幼苗水分利用效率及稳定碳同位素组成的研究

在模拟自然干旱的条件下,测定2个四倍体刺槐品种(K2、K3)和普通二倍体刺槐(K1)一年生组培苗的长期和瞬时水分利用效率(WUE)及其稳定碳同位素组成(δ13C),以探讨四倍体刺槐的抗旱机理.结果表明,K2、K3的长期水分利用效率(WUEL)在不同水分胁迫条件下都显著高于K1,它们在同等供水条件下比K1具有更大的生物量产出;3个材料叶片的瞬时水分利用效率(WUEI)均随干旱胁迫的加剧表现先升后降的趋势,且胁迫处理均高于适宜水分处理.随水分胁迫的加剧,各品种刺槐苗木叶片的δ13C显著升高;K2、K3的δ13C在各水分条件下均高于K1;各材料叶片的δ13C与其WUEL有良好的正相关性,可以作为筛选高WUE刺槐品种的指标.

Water Use Efficiency and Carbon Isotopic Compositions in Tetraploid Clones of Black Locust under Drought Resistance

By taking one-year-old micropropagated tetraploid clones of black locust (Robinia pseudoacacia L.) K2 and K3 as study objects,we evaluated their WUEL (long-term water use efficiency),WUEI (instant water use efficiency) and carbon isotopic compositions(δ13C) respectively under stimulant natural drought of soil.The same parameters of ordinary diploid K1 were evaluated as well as.The results indicated that WUEL of K2 and K3 was higher than that of K1 under drought resistance,which showed that K2 and K3 had more yield at the same irrigation.With the increase of drought stress,the WUEI increased firstly and then decreased for all three materials.The correlation between δ13C and WUEL was higher while water stress severer and severer.Therefore,δ13C can be the evaluation index to select material with high WUE from different clones of black locust.