不同倍性香石竹杂交受精过程及胚胎发育研究

采用石蜡切片法对以四倍体香石竹品种‘紫蝴蝶’(2n=4x=60)为母本,单瓣中间材料‘NH6’(2n=2x=30)为父本杂交后受精过程及胚胎发育进行研究。结果表明:(1)授粉后17h,花粉管进入助细胞并释放内容物,精核进入极核细胞内,与二极核细胞融合形成初生胚乳核;授粉后1d,精核向卵核方向移动,贴伏于卵核核膜上;授粉后2d,形成合子及游离的胚乳核;随后,胚发育经过原胚、球形胚、心形胚、鱼雷形胚阶段。(2)杂交障碍发生在受精过程及胚胎发育的各个时期,表现为:精子与卵细胞不相融合或精子与二极核不相融合、合子未分裂或初生胚乳核未分裂及胚胎的败育。(3)胚败育虽能发生在原胚、球形胚、棒状形胚、三角形胚、心形胚、鱼雷形胚及子叶形胚阶段,但主要发生在球形胚阶段。

Fertilization and Development of Embryo in Different Interploidal Crosses of Dianthus caryophyllus

Function of AZI1 in Arabidopsis resistance to Pseudomonas syringae was analyzed using overexpressing,T-DNA knockout and wild-type lines.(1)The expression of AZI1 could be induced by P.syringae,H₂O₂ and ethephon,indicating AZI1 is involved in salicylic acid- and ethylene-mediated antimicrobial pathways.(2)Western blotting analyses showed that AZI1 and its paralog EARLI1 existed in petiole exudate.They could form complexes with other proteins.It suggested that AZI1 possibly moved to other sites of plants through vascular tissue and related with signal transduction.(3)AZI1 and its paralog EARLI1 mainly expressed in lignified tissues of inflorescence stems,overexpression of AZI1 could promote biosynthesis of lignin and enhance the resistance of Arabidopsis to P.syringae.AZI1 belongs to lipid transfer protein (LTP) family.It may play important functions in transduction of signal molecules during defense response of Arabidopsis to infection of P.syringae.