桂两优 2号对水分胁迫及复水的生态生理响应

为探究水稻孕穗期和灌浆期对水分胁迫响应的差异，以桂两优 2 号为试验材料，通过盆栽试验，在孕穗 期和灌浆期进行水分胁迫及复水处理，研究其对水稻根系形态特征，叶片 SOD、POD、CAT 活性，成熟期株高，干物质 积累的影响。 结果表明，水分胁迫及复水后，水稻根长、根数、根鲜重发生明显变化，影响成熟期株高及干物质的积 累，使叶片抗氧化酶活性升高。 水分胁迫对水稻生长生理的影响与水分胁迫程度及生育时期有关，适当水分胁迫不 会影响水稻的生长生理。 孕穗期对水分胁迫的敏感性比灌浆期大。

Eco-phys i ol ogy res pons esofGui l i angyou2 t o wat ers t res sand re-wat eri ng

The exper i mentwas conduct ed t o st udy t he di f f er entr esponses ofr i ce t o wat erst r ess atboot i ng and gr ai n f i l l i ng st age,usi ng Gui l i agnyou2 asexper i mentmat er i al s.Thr ough potexper i ment s,wat erst r essand r e-wat er i ng t r eat ment s wer e conduct ed t o r i ce atboot i ng and gr ai n f i l l i ng st age,and ef f ect s ofon r ootmor phol ogi calchar act er i st i cs,SOD,POD, CAT act i vi t i esi n r i ce l eaves,pl anthei ghtand dr y mat t eraccumul at i on atmat ur e st age wer e r esear ched.Resul t si ndi cat ed t hataf t er wat er st r ess and r e-wat er i ng,r ootl engt h,r ootnumber and r ootf r esh wei ghtofr i ce changed obvi ousl y,pl ant hei ght at mat ur e st age and dr y mat t er accumul at i on wer e i nf l uenced,and ant i oxi dant enz ymes act i vi t i es i n r i ce l eaves i ncr eased.Eco-physi ol ogi cal ef f ect s t o wat er s t r ess wer e associ at ed wi t h t he degr ee of wat er st r ess and gr owt h st age. M oder at e wat er st r ess di d noti nf l uence gr owt h and physi ol ogy ofr i ce.Ri ce atoot i ng st age was mor e sensi t i ve t o wat er st r esst han t hatatgr ai n f i l l i ng st age.