籼粳稻的花时对乙烯利调控的响应及其敏感性差异

摘要

花时不遇影响籼粳亚种间杂交稻制种产量的提高。喷施乙烯利可延迟籼粳稻的花时。研究在不同时间喷施不同浓度的乙烯利延迟籼粳稻花时性状的效果,比较籼稻和粳稻对乙烯利响应的敏感性差异,可为籼粳亚种间杂交稻制种花时不遇的问题提供解决途径和理论依据。本研究以6个籼稻品种(泸香618B、窄叶青8号、明恢70、2998B、明恢100和冈46B)和6个粳稻品种(空育131、越光、里歌、丰锦、秋光和秋田小町)为试验材料,于调查花时性状的前日17：00、当日6：00及当日8：00分别喷施0.0,1.5,2.0,2.5g•L-1浓度的乙烯利,调查始花时、盛花时、终花时及开花持续时间的变化。结果表明,喷施乙烯利可显著延迟籼粳稻开花。前日17：00喷施乙烯利延迟花时的效果最好,与当日6：00和当日8：00处理间的差异达极显著水平。不同浓度处理之间花时性状的差异不显著,但与对照相比差异达极显著水平。籼稻对乙烯利更为敏感,花时的延后幅度大于粳稻。对大多数籼粳材料来说,前日17：00喷施乙烯利可显著缩短始-盛时间(始花到盛花的持续时间)、盛-终时间(盛花到终花的持续时间)和始-终时间(始花到终花的持续时间)。籼粳稻都能响应低浓度(1.5g•L-1)、中浓度(2g•L-1)和高浓度(2.5g•L-1)的乙烯利,为提高亚种间杂交稻的制种产量,建议在抽穗开花期的前日17：00将1.5g•L-1的乙烯利喷施在籼型亲本上,可以显著延迟其始花时间,缩小与粳型亲本的花时差。%The differences of sensitivity of floret opening time to ethephon between subsp. indica and japonica rice were compared through studying the effects of different dosage ethylene sprayed at different time to flowering time for improving hybrid seeds production between subsp. indica and japonica rice. Six indica rice varieties and six japonica rice varieties were used as materials to investigate the dynamic of floret opening, through spaying ethephon with three dosages (0.0, 1.5,2.0,2.5g•L-1) and three time (17:00 last afternoon, 6:00 and 8:00 in the morning) at heading date. The result indicated that ethephon could delay time of floret opening in both indica and japonica rice. It could delay very significantly the time of floret opening of indica and japonica rice that sprayed ethephon at 17:00 last afternoon in contrast to the treatment with ethephon at 6:00 and 8:00 in the morning. No differences could be found among treatments with three dosage ethepon but there were very significant differences between treatments with ethephon and CK. The extent of floret opening time delay of indica rice was more than that of japonica rice. To the majority of indica and japonica rice, It could make the lasting time of floral opening short that sprayed ethephon at 17:00 last afternoon. In order to improve hybrid seeds production, we should spray 1.5g•L-1 ethepon on indica parents at 17:00 last afternoon to make synchronization of floret opening time between indica and japonica rice.