一个优良茄子矮化突变体的鉴定与评价

Identification and Evaluation of a Elite Dwarf Mutant in Eggplant

矮化是茄子育种的目标性状,但目前还缺少相应的优良种质资源。本研究在圆茄自交系‘14-345’的EMS突变体库中筛选出了一个可以稳定遗传的矮化突变体dwf,该突变体植株与野生型(wildtype,WT)相比矮化明显,分枝增多但株幅显著减小,适宜密植。经检测发现,dwf脱落酸(abscisic acid,ABA)含量增加可能是导致其植株分枝增多的主要原因之一。比较dwf及野生型WT的叶绿素含量和光合特性,发现dwf在六叶期叶绿素b和叶绿素(a+b)含量显著高于WT。定植后30 d dwf和WT的叶绿素含量、净光合速率(net photosynthetic rate,Pn)和叶绿素荧光参数均无差异,表明dwf在光能利用及转化方面与WT未存在差异。从转录水平分析dwf的抗病性分子机理发现,ABA含量升高和相关基因显著上调表达是突变体dwf对菌核病表现出抗性的主要原因。本研究可作为一份优良的矮化种质资源用于茄子遗传研究和育种实践。

Dwarfing is the target in eggplant breeding,but there is still a lack of elite germplasm resources for breeding.In this study a stable genetic dwarf mutant(dwf)isolated from an eggplant inbred lines’14-345’ethylmethyl sulfonate(EMS)-induced mutant library.dwf shows obviously dwarfism compare with wild type(WT),the branches increase but plant width significantly reduce which is suitable for compact planting.The increasing of abscisic acid content in dwf might be an main reason of increased branches.By testing the chlorophyll content and photosynthetic characteristics of dwf and WT,it was found that the contents of chlorophyll b and chlorophyll(a+b)in dwf are significantly higher than those in WT at six-leaf stage.But in the 30 days after planting,the chlorophyll content,Pn and other parameters related to photosynthetic characteristics of dwf and WT are no difference.The disease resistance molecular mechanism of dwf was analyzed by transcriptional and shows that the better disease resistance was mainly related to the increase of ABA content and the significantly up-regulated expression of stress adaptation genes.Therefore,dwf can be used as an elite dwarf germplasm for eggplant genetic research and breeding practice.