利用粳型广亲和恢复系与籼稻不育系配制籼粳亚种间杂种

Rice Hybrids Derived by Crossing Indica CMS Lines with Japonica Widely Compatible Restorers

对用粳型恢复系与广亲和系02428杂交选育出的一批农艺性状稳定的新的粳型恢复系进行亲和性和恢复力测定。结果表明,在所测定的9个株系中,有1个株系(87-3)能使协青早A和庆莲16A的育性恢复到69.6％和63.6％,有6个株系(87-1、87-3,87-4、87-6、87-7,87-8)能使六南早A的育性恢复到60％以上。杂种生长繁茂,穗粒优势十分明显,与品种间杂种相比具有更大的生产潜力。讨论了基于广亲和恢复系选育的三系法籼粳亚种间杂种优势利用的可能性及其育种价值。

The utilization of heterosis between indica and japonica has attracted numerous rice breeders and great efforts have been devoted to it, but less progress has been made. The main barrier is the incompatibility in crossing between indica and japonica. The exploitation of the wide compatibility (WC) gene offers effective approaches to the use of heterosis between indica and japonica. The objective of this study was to probe the possibility to develop hybrids between indica and japonica by crossing between indica CMS lines and widely compatible restorer lines (WCR lines). Japonica restorers C57, 77302-1, Ninghui 7, etc were crossed with the WC strain 02428 to develop WCR lines, and a number of WCR selections have been developed. In this study, the compatibility and restoring ability of 9 selections were tested by crossing them with indica and japonica CMS lines or varieties. One selection (87-3) showed spikelet fertility of 63.6-69.6% when crossed with indica CMS lines Xie-qingzao A, Qinglian 16 A and Liunanzao A, 76.7% with japonica CMS line 44640 A, and 81.4% and 73.6% with indica variety 3037 and japonica variety 76-27 (Table 1, Figs. 1,2), six (87-1, 87-3, 87-4, 87-6, 87-7 and 87-8) had fertility above 60% when crossed with indica type CMS line Liunanzao A (Table 1). The inter-subspecies hybrids grew luxuriantly with marked heterosis in number of panicles per plant and spikelets per panicle (Fig. 3), some of them showing greater productivity than intra-subspecies hybrids (Table 2). The possibility and significance of the use of heterosis between indica and japonica by the three-line method based on the development of WCR lines are discussed.