盐胁迫对冬小麦幼苗干物质分配和生理生态特性的影响

Effects of saline stress on dry matter partitioning and ecophysiological characteristics of winter wheat seedlings

以冬小麦（Triticum aestivum L.）品种周麦18（Zhoumai18）和豫麦49（Yumai49）为材料,采用盆栽培养,研究100、250、350mmol/L和450mmol/L NaCl浓度胁迫下,小麦幼苗干物质分配、根系特征、叶绿素含量、游离脯氨酸含量和根系活力变化规律。结果表明,随着盐分浓度的增加,两个品种小麦的叶面积、地上干重以及根的长度显著减小;根系干重、根直径、根表面积、根体积、根系活力以及叶绿素含量呈先上升后下降趋势,在250mmol/L NaCl处理下达最大。叶绿素a/b随NaCl浓度升高而上升。随盐分浓度变化周麦18叶片游离脯氨酸含量高而变化幅度大,450mmol/L处理组的含量高于对照组1.5倍。供试品种冬小麦耐盐阈值为250-350mmol/L。

Dry matter partitioning, root characteristics, chlorophyll content, free proline content and root activity were investigated in potted seedlings of winter wheat （ Triticum aestivum L. ） cultivars （Zhoumail 8 and Yumai49） with Hoagland solution and Hoagland adding 100, 250, 350, and 450 mmol/L NaCl, respectively. The results showed that leaf area, aboveground dry weight and root length in both cultivars significantly decreased in a salinity concentration-dependent manner. In contrast, root characteristics parameters （ie. dry weight, diameter, surface area, volume）, root activity and chlorophyll content expressed a trace with a peak at 250mmol/L NaCl ; Chla / Chlb ratio were positively correlated with soil salinity. Proline content was higher and fluctuated much more in Zhoumail8 than in Yumai49, and 350 mmol/L NaCl increased the proline content by 1.5 times vs control. The threshold of salinity tolerance was somewhere between 250 and 350 mmol/L in winter wheat under study.