小麦碳同位素分辨率对水分的响应分析

Response Analysis of Correlation between Carbon Isotope Discrimination of Wheat and Water

为了研究不同发育时期小麦各器官Δ13C的变化规律及Δ13C对水分的响应,以18个西北地区小麦地方品种和育成品种(系)为试验材料在两种生态条件下进行不同灌水处理,测定分析了各品种旗叶、茎秆和籽粒的碳同位素分辨率(Δ13C值)及其与产量的相关性。结果表明,小麦拔节及开花期各器官Δ13C随土壤水分的增加而持续增加,生育前期(苗期—拔节期)水分胁迫比生育后期(抽穗—成熟期)的水分胁迫对各器官Δ13C的降低程度更大,产量也有相同的趋势。在土壤水份较充足或只是生育后期土壤缺水的条件下(T3,T4,T5),开花期旗叶、基部节、成熟期旗叶和基部节的Δ13C与产量均呈正相关,其中T5处理开花期旗叶、基部节和成熟期基部节Δ13C与产量呈显著正相关,相关系数分别为0.533 8^*、0.503 3^**和0.535 2^*。各器官Δ13C呈规律变化:叶片>基部节>籽粒。同一品种不同部位Δ13C存在较大差异,开花期旗叶、基部节、成熟期旗叶和基部节Δ13C值相对较高,成熟期籽粒Δ13C值最低。灌区和雨养地区高水分利用效率品种的选择指标分别为开花期基部节、成熟籽粒Δ13C和拔节期叶片Δ13C。

In order to study the different developmental stages of wheat organsΔ13C changes and the response ofΔ13C to water,18 northwest local wheat varieties and breeding varieties(lines)were grown on different irrigation treatments in Ningxia,the correlation between the carbon isotope discrimination of wheat leaves,stem,grain and yield were analysised.The results showed that the carbon isotope discrimination(Δ13C)of each organ in stage of elongating and flowering were continue to increase along with the increase of soil water.Water stress affects theΔ13C in the early stage(seedling stage to jointing stage)greatly than the later stage(heading stage to mature stage),yield also has the same trend.TheΔ13C of flowering stage flag leaf,stems mature stage flag leaf and stems were positive correlation with yield under soil water were sufficient or only late grouting(T3,T4,T5),the correlation coefficient ofΔ13C of flowering stage stems,mature stage flag leaf,stems and the grain with yield were 0.533 8^*,0.503 3^*and 0.535 2^*under T5.Each organ ofΔ13C showed that leaf>stems>grain.There were bigger variation for theΔof the same variety in different positions,theΔ13C of wheat grain lower than flowering stage flag leaf and stems,mature stage flag leaf and stems.TheΔ13C flowering stems、mature grain and jointing stage leaf were the irrigation and rain area high WUE indexs.