CaCl_(2)浸种对苗期干旱胁迫下花生生长、生理及产量的影响

Effects of Seed Soaking with CaCl_(2) on Growth,Physiological Characters and Yield of Peanut under Drought Stress at Seedling Stage

本试验以商花30号和商花26号为材料,研究不同浓度CaCl_(2)浸种对苗期干旱胁迫下花生生长、生理及产量的影响。结果表明,苗期干旱显著抑制两个花生品种的营养生长,叶片叶绿素含量(SPAD值)下降,超氧化物歧化酶(SOD)和过氧化物酶(POD)活性升高,丙二醛(MDA)含量增加;复水后两品种CaCl_(2)浸种处理SPAD值升高,SOD和POD活性以及MDA含量恢复到正常供水处理(CK1)水平。与单纯干旱胁迫(CK_(2))相比,干旱胁迫下CaCl_(2)浸种处理花生株高、叶面积指数、植株干重、SPAD值、SOD和POD活性显著提高,MDA含量显著下降。商花30号以40mmol/LCaCl_(2)浸种、商花26号以60mmol/LCaCl_(2)浸种效果最好,荚果产量分别比单纯干旱胁迫处理(CK2)增产13.90%和15.52%。说明苗期干旱胁迫下CaCl_(2)浸种可以通过提高叶片叶绿素含量和SOD、POD活性,降低MDA含量,增强活性氧清除能力,从而增加干物质积累,最终提高产量。

In this experiment,the peanut cultivars Shanghua 30 and Shanghua 26 were used to analyze the effects of seed soaking with different concentrations of CaCl_(2) on growth,physiological characters and pod yield under drought stress at seedling stage.The results showed that drought stress at seedling stage significantly inhibited the vegetative growth of both peanut cultivars,reduced the leaf chlorophyll content(SPAD),and increased superoxide dismutase(SOD)and peroxidase(POD)activities and malondialdehyde(MDA)content.After irrigation,the SPAD value of the two peanut cultivars increased by seed soaking with CaCl_(2),and the SOD,POD activities and MDA content returned to the level under normal water treatment(CK1).Compared with only drought stress treatment(CK2),the plant height,leaf area index,plant dry weight,SPAD value and SOD and POD activities significantly increased,and the MDA content significantly decreased under drought stress but with CaCl_(2) application.The optimal seed soaking concentration of CaCl_(2) for Shanghua 30 and Shanghua 26 were 40 mmol/L and 60 mmol/L,respectively,and the pod yield increased by 13.90%and 15.52%respectively compared with CK_(2).Altogether,these results indicated that seed soaking with CaCl_(2) could increase the pod yield of peanut under drought stress at seedling stage due to increasing chlorophyll content and reactive oxygen scavenging capacity through increasing SOD and POD activities and decreasing MDA content.