花药培养对籼稻两用核不育系培矮64S的提纯与改良

PURIFICATION AND IMPROVEMENT ON DUAL-PURPOSE GENIC MALE STERILE RICE PEIAI 64S BY ANTHER CULTURE

摘要:

以籼稻两用雄性核不育系(简称两用系)培矮64S为供体,通过花药培养,获得了26个愈伤系共1 969株花粉植株.根据花粉一代(H1)的倍性和育性,可把它们分为三种类型,即 a)单倍体:有1个愈伤系41株全为单倍体植株；b)不分离型:有19个愈伤系的群体育性不分离,全部植株均在不育期表现败育,其它性状有差异但不显著；c)分离型:其余6个愈伤系表现分离,其中3个各有2-7株单倍体植株出现,并且这些愈伤系中均有花粉染色率及自交结实率较高的植株。未经培养的供体两用系(对照)群体中也有1.5%的植株为可育株,说明应用多年的培矮64S有关育性的基因型并不纯合。经过两代的选择,至H₃代,所选育的105个单株后代中,个体之间的表现整齐一致。H₄代分4期播种,各期的播始天数呈由长到短的变化趋势,表现出生育期感温性的特点。同时观察到,其稳定不育期比对照长3 d左右,育性转换期结实率比对照高5.8%以上。测交了108个组合,各组合F₁代均表现出高产的特性。研究表明,花药培养是提纯及改良两用系的有效途径。

Abstract:

Anther culture of a dual-purpose genic male sterile rice (DGMSR) Peiai 64S resulted in 1969 regenerated plants from 26 callus lines. According to the ploidy and fertility in the first generation of anther plants (H1 ), they were divided into three types: a) Haploid, all of the 41 plants in 1 callus line were haploid, b) Uniform type, including 19 callus lines, all of which were sterile during the sterility period, and no remarkable differences in other characters were observed, c) Segregation type, including the remaining 6 callus lines which exhibited segregation．In this type，3 lines with 2 to 7 individuals each were haploid．Some plants in this type had higher pollen staining rate and seed setting percentage. In the control line (Peiai 64S)，there were 1.5％ of individuals being fertile in sterility period，indicating that Peiai 64S was not a pure line. After selection for two generations，their fertility has been stable in H₃. The experiments of sowing at intervals in spring with seven lines in the H₄ generation showed，the later the sowing date，the earlier the initia1 heading date．It was shown that these 1ines were susceptible to tem perature．It was also observed that the duration of stable sterility period in the selected plant lines was longer by 3 days or so than that in the control，and in fertility transformation period，the seed set percentages from self-pollination in these lines were over 5 8％ higher compared to the contro1．The characters of F₁ hybrids from 108 test cross combinations showed potential high-yield trait. It is suggested that anther culture is an effective way for purifying and improving DGMSR.