光敏核不育水稻在寒冷稻作区的育性转换特性及开花习性

Fertility Alteration and Flowering Habits of Photoperiod Sensitive Genic Malesterile Rice (PGMR) in the Cold Region

光敏核不育水稻(PGMR)的发现与深入研究给杂交粳稻的发展带来了新的途径,但易受气候条件影响的特点又制约了其应用的范围。因此,为了采用相应的育种手段在寒冷稻作区利用这种资源,尚需进一步弄清其在本生态区的表现特点。本文的目的是通过观察31116S等代表性的粳型PGMR的育性转换特性和开花习性,为有效地将其应用于寒地杂交粳稻的选育提供参考资料。1 材料与方法1989年自辽宁、武汉等地引入31116S、N5047S、6085S、6283S等4份有代表性的粳型PGMR,并经海南自交繁殖,1990年在吉林省农科院水稻试验田(43°31′N)分期播种(表1)。并以31116S为试材,每隔3～4d播种一批(图1),4叶1心时移栽大田,株行距13.3cm×30cm,3行区,每行20株。以31116S、N5047S、6085S、6283S为材料,设置13.0、13.5、14.0、14.5、15.0h 5种不同光照时间处理。具体做法是每处理用塑料槽种30株,株行距10cm×20cm,同一光长处理的不同材料种植于同一槽内,用3层黑布遮光严密。

Fertility alteration characteristics and flowering habits of PGMR were studied under the local natural condition in Gongzhuling (43°21′N) and problem of using PGMR for hybrid rice breeding in the cold region were discussed. The critical photoperiod of fertility alteration of PGM R was 14.5～14.0 hours, but the local photoperiod could only meet the requirement of sterility of PGMR in the cold region over 38°N. Daily flowering time of PGMR was about 1 hours later and more dispersive than these of normal variety. It was low in the crossed pollination rate between PGMR and normal variety. Sterility of existing PGMR was unstable in the cold region. Fertility of PGMR was affected by temperature during differentiation stage of floret primodium.