土壤水分胁迫对燕麦叶片渗透调节物质含量的影响

以旱棚内盆栽的'内农大莜一号'燕麦品种为材料,测定了其不同水分胁迫下各生育期叶片的脯氨酸、可溶性糖含量和细胞膜相对透性,分析土壤含水量对燕麦叶片渗透调节物质的影响,以明确燕麦不同生育时期的抗旱特性.结果表明:(1)随着土壤相对含水率的下降,燕麦各生育期叶片脯氨酸含量、可溶性糖含量、细胞膜相对透性均呈上升趋势.(2)随着生育期的推进,燕麦叶片脯氨酸含量在30%和45%土壤含水量下呈持续上升趋势,而在含水量 60%、75%、90%处理下则于生育前期上升,灌浆期略有下降;随着生育期的延续,可溶性糖的含量呈先升后降的抛物线型变化,且其最大值随水分胁迫强度增加而提前,含水量 30%和45%处理的最大值均出现在拔节期,含水量60%和75%处理则分别出现在孕穗期和开花期;随着生育期的延续,各处理燕麦叶片的细胞膜相对透性均呈持续上升趋势.可见,水分胁迫能诱导燕麦叶片渗透调节物质的积累,且增幅随着胁迫强度的增加而上升,从而使燕麦表现出较强的抗旱性.

Change of Osmotica in Oat Leaf under Soil Moisture Stress

Impacts of soil moisture availability on osmotica in leaves of oat at different soil moisture stress levels were investigated using a cultivar-Neinongda No.1 grown in pots under rain-proof shelter.In the experiments, proline and soluble sugar contents in leaves and relative permeability of cell membrane of leaves at different development stages were determined.Proline and soluble sugar contents and relative permeability of cell membrane of leaves at all stages increased with the decline of soil moisture.Proline contents in leaves under 30% and 45% soil moisture treatments increased with the growth of oat,but those under 60%,75% and 90% soil moisture treatments rose until filling stage and then decreased.Soluble sugar contents during the whole growth stage presented a parabolic curve,with maximums occurring at earlier stages when moisture stress intensified,e.g.,at elongation stage under 30% and 45% soil moisture treatments,but at booting and flowering stages under 60% and 75% soil moisture treatments,respectively.Relatively permeability of cell membrane increased with the growth of oat. Therefore,soil moisture stress stimulated osmotica accumulation in oat leaves,more osmotica accumulated under heavier moisture stress.