水稻旱育秧苗萎蔫反应及其生理响应研究

Study on wilting reaction of dry nursery seedlings and physiological response to it

从旱育秧苗离土萎蔫反应及其生理响应方面初步研究了旱育秧苗的水分生理特性和对其抗旱性的影响。结果表明 :旱育秧苗离土后达到临界萎蔫时间比水育秧早 6 0min左右 ,失水速率较快 ,但旱育秧苗临界萎蔫后失水速率比水秧苗低 5 5 2 % ,且临界萎蔫后旱育秧苗在水中恢复展叶所需时间短于水秧苗 16 0～ 2 14min ,吸水速率是水秧苗的 2 4～ 6 3倍。旱育秧苗在离土—临界萎蔫—再吸水恢复展叶过程中 ,叶片中硝酸还原酶活性 (NRA)分别是水秧苗的 2 7～ 2 1 1倍、 6 3～ 17 5倍、 13 0～ 2 1 0倍 ;秧苗体内NO 3 含量变化趋势与NRA类似 ;旱秧苗体内脯氨酸 (Pro)含量在萎蔫时快速升高 ,且高于水秧苗 ,而在水中恢复展叶时Pro含量又快速下降 ,叶片Pro含量低于水秧苗。由此可见 ,旱秧苗水分反应灵敏 。

The wilting reaction of dry nursery seedlings and physiological response to it were studied.The results showed as follows:Compared with moist nursery seedlings(MNS),dry nursery seedlings(DNS)wilted much easily,60 minutes early.But after wilting,the rate of losing water of DNS was 55 2% slower than that of MNS. And the duration of DNS recovery from critical wilting was 160?214 minutes shorter than MNS when dipped in water.The rate of water absorption of DNS was as 2 4?6 4 times as that of MNS.From wilting in air to recovery in water,the NRA in leaves of DNS was as 6 3?17 5 times and 13 0?21 0 times as that of MNS,respectively.Proline content of DNS was much higher than MNS while wilting,but lower than MNS while recovery in water.These physiological characteristics indicate that DNS have stronger drought resistance,and can recover more rapidly than MNS.