抗真菌转基因水稻纹枯病抗性的杂种优势分析

Heterosis analysis of resistance to sheath blight of transgenic hybrid rice with extra anti-fungus genes

用抗纹枯病的12个转入1～4个外源抗真菌基因的转基因水稻作父本,分别与2～3个雄性不育系配组,采用田间人工接种纹枯病菌的方法,从3个抗性指标上研究了转基因杂交水稻纹枯病抗性的杂种优势。结果表明,杂交水稻的抗病性与转基因父本显著正相关,抗病性的广义遗传力为0.52～0.83。在29个杂交组合中,有5个组合具有显著负向超低亲(父本)优势,但群体平均超低亲优势大于0,为35.01％～50.79％;杂交稻群体的平均负向竞争优势明显,强度大,为-57.60％～-31.23％,有38％的组合具有显著负向竞争优势,说明转基因杂交水稻的抗纹枯病性普遍低于转基因水稻父本,但仍具有较好抗性,并可从中筛选出强优势组合。

Twelve high resistant transgenic rice lines with 1 -4 extra anti-fungus genes were crossed with 2-3 male-sterial rice lines. Heterosis analysis of resistance of transgenic hybrid rice to sheath blight was studied with 3 resistance indices under the condition of artificial inoculation in field. The results showed that the resistance of transgenic hybrid rice had positive correlation with transgenic male parentage and the value of broad hereditary capacity was 0.52 - 0.83. Among 29 hybrid combinations, 5 combinations had significantly negative heterosis over lower parents （ HLP）, but the average value of HLP of all combi- nations was 35.01% - 50.79%, was positive. The average negative heterosis over control （ HC ） of all combinations was strong, the value was - 57.60% - - 31.23%. The 38% hybrid combinations had remarkable negative HC. It indicated that the resistance of transgenic hybrid rice was usually lower than its transgenic male parents, but it still was resistant. The strong heterosis hybrid combinations with high resistance could be selected among the combinations.