沙打旺与鹰咀紫云英种间杂交不亲和性研究

Interspecific Cross-Incompatibility Between Astragalus adsurgens Pall.and A.cicer L.

沙打旺抗逆性强 ,而鹰咀紫云英品质较好 ,是黄芪属中优良性状互补的草种。针对二者种间杂交不亲和性现象 ,从不同方面研究杂交不亲和的原因。结果表明 ,亲本花粉活力和育性均非杂交不亲和的主要原因 ,其主要障碍在于 ,父本花粉不能伸入母本柱头 ,表现出不亲和异常现象 ,如花粉管萌发后盘绕在柱头表面 ,花粉管尖端膨大等。即使父本花粉管进入母本柱头 ,因生长缓慢 ,沉积胼胝质 ,在花柱中受抑制而停止生长。沙打旺和鹰咀紫云英杂交不亲和的表达部位与亲本自交不亲和的表达部位相似。在此基础上提出克服二者杂交不亲和的措施 ,为沙打旺和鹰咀紫云英杂交育种提供理论基础和依据。

The characteristics of Astragalus adsurgens Pall.with strong resistance and A.cicer L.with good quality are complementary in the genus Astragalus .Cross incompatibility and pollen stigma interaction were studied in different sides because hybrids failed to get between A.astragalus Pall.and A.cicer L..The results showed that parental pollen vigor and fertility were not the main cause of cross incompatibility.It expressed as followed:Firstly,pollen tubes failed to enter into materal stigma,some pollen tubes twined on the surface of stigma after germination,often with tips inflation or bursting. Secondly,if pollen tubes entered into stigma,growth was retarded with callose plug deposition,then they stopped to grow because of inhibition.The expression sites of cross incompatibility between A.adsurgens Pall.and A.cicer L.were similar to ones of parental self incompatibility.In according to the research results,methods which could overcome hybridization barriers were put forward.It will offer foundation for hybridization breeding of A.astragalus Pall.and A.cicer L.