【摘要】 经过3代自交纯化与稻瘟病抗性鉴定,在1500份普通野生稻(Oryza rufipogon Griff.)中发现38份抗病材料,在113份药用野生稻(O.officinalis Wall.ex Watt.)中发现18份抗病材料。普通野生稻和药用野生稻相同材料在不同年份的田间病区诱发鉴定中,各级抗性植株分布差异不显著,鉴定结果表现一致。与普通野生稻相比,广西药用野生稻抗性基因发生的频率显著较高、抗性稳定,是一种特殊抗性类型,从中获得具有重要利用价值的新抗性基因的可能性较大。研究还表明,自交提纯能够明显提高这两种野生稻的平均抗性水平。在田间病区诱发条件下,广西普通野生稻抗性材料出现的频率与地区居群的遗传多样性没有显著相关性。更多还原

【Abstract】 Rice blast,caused by Magnaporthe grisea,is one of the most destructive diseases in rice worldwide.Exploitation of resistance gene resources for rice breeding is of most importance in control of this disease.Thirty-eight of 1500 accessions of Oryza rufipogon Griff.and 18 of 113 accessions of O.officinalis Wall.ex Watt.originated from Guangxi,China were found to be resistant to the disease.In natural field nursery assessment,there was no significant difference in the frequency distributions at different disease index levels in different years for O.rufipogon and O.officinalis.The frequency and resistance stability of resistant plants in O.officinalis were obviously higher than those in O.rufipogon,which indicated that the O.officinalis species was a specific resistant type to the blast,with new type of resistance genes of important value.The study also indicated that homozygosity by selfing could significantly enhance the mean resistance level of O.rufipogon and O.officinalis.In natural field nursery assessment,the ratio of resistant plants had not significant correlation with genetic diversity in the regional population groups of O.rufipogon.更多还原