【作者】 樊志明；

【导师】 吴江生； 刘克德；

【作者基本信息】 华中农业大学 ， 作物遗传育种， 2010， 硕士

【摘要】 植物远缘杂交是作物育种、种质资源创新和新型不育材料创建的一条重要途径。芸薹属植物是一个遗传类型极其丰富、用途广泛的物种。前人已经做了大量关于芸薹属与萝卜属、白芥属、二行芥属及芸薹属内种间远缘杂交的研究工作,创造了大批油菜、蔬菜新品种和不育系。在本研究中,以萝卜与甘蓝远缘杂交获得的萝卜甘蓝双二倍体及其不育系8109为实验材料,观察其植物学性状,研究不育系的遗传特性及花药发育,取得的主要结果如下：1)萝卜甘蓝双二倍体在植物学形态上有别于母本萝卜和父本甘蓝,介于亲本之间。萝卜甘蓝双二倍体基叶表现为裂叶、顶叶大而圆、叶片表面光滑、有少量腊粉；花器官发育正常,花型偏向父本甘蓝,花瓣比亲本大,呈白色；角果形态呈两截,上半部分外部形态与萝卜角果相似,木质化严重,不容易开裂,下半部分与甘蓝角果相似,荚果皮较薄,容易开裂。2)不育系8109花器官发育不正常,表现为死蕾,雄蕊短缩,花药为乳白色,且呈三角状,未见花粉存在。3)通过花粉活力检测和田间套袋自交检测,发现不育系8109败育彻底、稳定遗传；通过测交实验,发现2个恢复系8024和8057,但没有找到保持系。4)F2代可育株与不育株的分离比为3：1,BC1代可育株与不育株的分离比为1：1,符合一对隐性基因的分离比例,表明此不育性受一对隐性基因控制。5)石蜡切片观察结果表明,不育系8109花粉败育发生的关键时期在四分体至单核期,此时绒毡层出现多层细胞及液泡化现象；随着时间的推移,不育花药绒毡层液泡化现象逐渐加重,绒毡层细胞表现为扩大、不育小孢子没有花粉外壁,在小孢子单核晚期,绒毡层与小孢子一起解体,直至形成空的花粉囊。更多还原

【Abstract】 Distant hybridization is an important strategy for plant breeding, germplasm enhancement and novel male sterile lines creating. Brassica include abundant and extensively used genetic accessions. Great efforts of intarspecies cross in Brassica and interspecies cross between Brassica and Raphanus, Sinapie, Diplotaxis have been made, creating many new varieties or male lines of rapeseed and vegetables.In this study, the morphological features of amphidiploid between Raphanus sativus and Brassica alboglabra was observed. In addition, the heredity and cytological characteristics of male sterility line 8109 derived from this amphidiploids were studied. The main results are as follows:1) The amphidiploid was morphologically different from its parents. There were cleft leaves at base, and the parietal leaves were large and round with a small amount of wax powder, of which surface was smooth; The floral organ developed normally, similar to paternal Brassica alboglabra, but with white and larger petals compared to patents; The pod showed dumbbell-like, the external morphological characteristics of which in top half was similar to Raphanus stativus pod with serious lignification and cracking difficultly. On the contrary, the skin of lower part of pod was thinner and easy to crack, that was similar to Brassica alboglabra.2) The male sterility line 8109 showed some abnormal phenotypes, such as dead buds, short stamens, white and triangular anther and non-pollen.3) Through the pollen viability test, self-pollination test, and other methods, we found the male sterility line 8109 is sterile completely. The male sterility line 8109 had been crossed with other varieties, and two restorer lines 8024 and 8057 were found.4) The F2 population segregated at a 3:1 ratio for fertility/sterility, and the BC1 population segregated at a 1:1 ratio for fertility/sterility, following the segregation proportion of a single recessive gene. These results suggested that the fertility was controlled by a single recessive gene.5) To observe the developmental differences between male fertile and male sterile anthers, microscopic observation on anther development process of fertile and male sterile anthers was performed with paraffin sections. The results showed that the key stage of male sterility was from tetrad to microspores. At this stage, many layers cell appear on tapetum. With the development of microspore, the tapetum of male sterile anther enlarged radial with a number of larger vacuoles; the surface of male sterile microspore was smooth without exine formation. Till the stage of later microspore, tapetum and microspores were disaggregated to be an empty pollen sac.更多还原