苜蓿叶片碳同位素分辨率与水分利用效率的关系  

Relationship between Discrimination of Carbon Isotope in Leaf and Water Use Efficiency of Medicago sativa L.

作　　者：朱林[1,2] 高雪 张会丽[3] 许兴 

机构地区：[1]宁夏大学西北土地退化与生态恢复国家重点实验室培育基地,宁夏银川750021 [2]宁夏大学西北退化生态系统恢复与重建教育部重点实验室,宁夏银川750021 [3]宁夏大学农学院,宁夏银川750021

出　　处：《中国草地学报》2018年第1期17-23,共7页Chinese Journal of Grassland

基　　金：国家重点研发项目(2016YFC050706);宁夏回族自治区牧草育种专项(2014NYYZ0401);国家自然科学基金项目(31160478)

摘　　要：在宁夏中部荒漠草原区设置三种水分处理,种植了10个遗传背景不同的紫花苜蓿(Medicago sativa L.)品种,分析了不同组分Δ^(13)C与蒸腾蒸发量(ET)、水分利用效率(WUE)和产量的关系。结果表明:随着灌水量的增加,苜蓿不同茬次干草产量、ET、叶片Δ^(13)C、叶片可溶糖Δ^(13)C和第一、第三茬WUE显著增加,但第二茬WUE降低。叶片Δ^(13)C在第一茬低水条件下(T1)与ET显著负相关,在第二茬T1和中水(T2)条件下与WUE显著正相关、在第二茬T1条件和第三茬高水(T3)条件下均与产量显著正相关。叶片可溶糖Δ^(13)C在第二茬T1条件下与ET呈显著负相关、与WUE显著正相关,在第三茬T3条件下与ET和WUE显著正相关,在第一、第三茬T3条件下与产量显著正相关。在全年尺度(三个茬次)上,叶片Δ^(13)C在三种水分处理下均与WUE显著正相关(P<0.01),叶片可溶糖Δ^(13)C仅在T1和T2条件下与WUE显著正相关(P<0.05)。综合分析认为:在宁夏荒漠草原有灌溉条件(200~990mm)下选择高叶片Δ^(13)C的苜蓿基因型有利于提高长期水平的WUE。Ten Medicago sativa L.genotypes with different genetic background were planted in Ningxia central desert steppe with three water treatments.The relationship between Δ^（13）C of different fractions and ET,WUE and yield was analyzed.The results showed that yield,ET,leaf Δ^（13）C（ΔL）and leaf soluble carbohydrate Δ^（13）C（ΔWSC）increased significantly when irrigated water increased.Enhanced irrigation amounts increased WUE during the first and third cuttings and decreased WUE during the second cutting.ΔL was related negatively with ET in the least irrigation treatment（T1） during the first cutting,and correlated positively with WUE in T1 and intermediate irrigation treatment（T2） during the second cutting.There were positive correlations betweenΔLand yield in T1 during the second cutting and in T3 during the third cutting.ΔWSC was correlated negatively with ET and positively with WUE in T1 during the second cutting,and was related positively with ET and WUE in T3 during the third cutting.There were significant and positive correlations betweenΔWSCand yield in T3 during the first and third cuttings.When the data of three cuttings were pooled together,ΔLwas correlated with WUE significantly and positively（P〈0.01）under all the water treatments,whileΔWSCwas only related with WUE positively and significantly in T1 and T2（P〈0.05）.To sum up,in Ningxia desert steppe with irrigation from 200 mm to 900 mm,selection of Medicago sativa L.genotypes with high leaf Δ^（13）C would improve long term WUE.

关 键 词：苜蓿 碳同位素分辨率 宁夏中部荒漠草原 水分利用效率 

分 类 号：S541[农业科学—作物学]