不同类型光敏核不育水稻育性转换特点及应用研究

经1986～1988年.先后对十八套不同亚种类型的光敏感核不育系,在江西南昌,连续三年进行分期播种试验,已得到如下主要研究结果:1.基本探明了供试的十八套不同粳、籼亚种类型的光敏感核不育系,在南昌(28°41′N)的育性转换时期、阶段及稳定性.经育性转换及杂一代优势观察,已筛选出育性转换、开花习性及经济性状较好的粳型双9—2S、28006S和籼型W6417S、W6154S、赣ⅢS等光敏感核不育系.2.不同亚种类型及同一亚种不同品种的光敏感核不育系,其育性转换特点有明显差异.一般规律:籼型核不育系,普遍存在不育期较长,转育较晚,同时可育期易受低温影响结实的特点;而粳型核不育系,则普遍较籼型核不育系的不育期为短,育性转换较早,不育期因高温影响,常有部分散粉自交结实现象,但可育期因低温影响结实不明显.3.鉴于不同亚种类型光敏核不育系的育性转换特点不同,结合其开花习性差异对杂交制种的影响,从育种应用出发,研究提出:我国长江中下游稻作区,水稻光敏核不育系的选育,应重点主攻籼亚种,首先突破早熟早籼为宜.在选材上优先考虑矮秆、抗病、优质以及开花习性好,柱头外露率高等性状.

Applied Research on Fertility Transforming Traits of Photoperiod-sensitive Genetic Male Sterile Lines of Different Rice Subspecies

Experiments of periodic seeding of 18 entries of photoperiod-sensitive genetic male sterile (PGMS) lines of different subspecies were conducted all year round for three con sccutive years from 1986 to 1988 in Nanchang, Jiangxi. The main results are as follows: 1. Periods, stages and the stability of fertility transformation of 18 entries of Indica and Japonica PGMS lines in Nanchang region (28°41′N) have been basicly ascertained. Passing through fertility transformation and heterosis observation on F1 hybrids, some of PGMS lines as Shuang 9-2 S and 28006S of Japonica and W6417S, W6154S and Gan III S of Indica have been screened out and developed, which showed better fertility transformation , flowering habit and economic characters. 2. There exsits significant differences in fertility transformation among subspecies and varieties of the same subspecies. In general , Indica PGMS lines performs a long sterile period , late fertility transformation and seed setting is apt to low temperature in fertile stage , while Japonica PGMS lines are of shorter sterile period and earlier fertility transformation than Indica lines. And the partial selfing from pollen shedding arc often observed in Japonica because of high temperature during sterile period, however, seed setting is not evident under the influence of low temperature in the fertile period. 3. Based on the differences of fertility transformation of PGMS lines among different subspecies and with the influence of flowering diversity on hybrid seed production, it is suggested that the primary stress be layed on the Indica type and first of all on the early maturing Indica of early season rice in breeding PGMS lines for the rice regions of middle and lower reaches of the Yangtse River,and in addion, the breeding priorities be given to those materials of dwarf plant, disease resistance, better grain quality and flowering habit and a high rate of stigma exsertion.