粳型陆稻恢复系资源的筛选及其利用研究

对不同粳稻不育系与146个粳型陆稻品种测交所得21 7个组合的结实率观测结果表明,测交组合的平均结实率为36.3%,其中24个组合(占11.1%) 的结实率＞70%,说明与普通粳稻不同,粳型陆稻品种中存在丰富的恢复系资源.与不同地区的陆稻品种测交,不同质源的不育系的可恢性有一定差别.对7个组合的产量、8个组合的米质(糙米率和垩白粒率)与其相应的父本进行比较的结果表明,测交组合产量优势明显,且米质也得到显著改善.另对2个测交组合进行旱作种植,不仅比大面积应用的杂交粳稻黎优5 7大幅增产(增幅达93.2%),而且比陆稻父本也增产;在旱种和水田条件下产量接近黎优 57的水平.如对亲本进一步筛选和改良,有望育成水旱兼用、在不同栽培条件下均能显著增产的水陆稻杂交种,在旱涝并存地区具有广阔的应用前景.

Studies on Screening and Utilization of Restorer Resources in Upland Japonica Rice

F 1 hybrids from 146 upland japonica rice resources crossed with japonica cytoplamic male sterile (CMS) lines of different cytoplasms (mainly Boro type and IR24 type used in this study) were surveyed on their seed setting rate (SSR). The results showed that the average SSR of all hybrids was 36.3% and 24 hybrids (11.1%) had an SSR more than 70%, indicating that the restorer germplasms are rich in upland japonica rice (No restorer gene to Boro type CMS lines has been found in common japonica rice). The CMS lines with different cytoplasms showed different restorability when they were crossed to the upland japonica rice varieties from different regions. Seven and eight F 1 hybrids were compared with their upland male parents in grain yield and quality (brown rice recovery (BRR) and chalky rice percentage (CRP)), respectively. It was found that the grain yield of F 1 hybrids was much higher than (by 50.1% on average) and the grain quality was remarkably improved to that of their corresponding restorer lines. Two combinations were experimentized under different irrigating conditions. They showed a much higher yield under dryland conditions (by 93.2%) but a little bit lower yield (not significantly different in statistics) under semi dry and irrigated conditions than the check Liyou 57, a widely used japonica hybrid rice combination. It is expected that the hybrids between rice and upland rice with strong heterosis in grain yield under both irrigated and non irrigated (dryland) conditions could be developed through futher selection and improvement to the existing upland rice resources.