大豆不育细胞质资源的发掘与鉴定

Identification and Evaluation of New Sources of Male-Sterile Cytoplasm in Soybean

利用质核互作雄性不育系NJCMS1A的4个保持系为核背景测验种(父本)从大豆资源中筛选新不育细胞质,发现与71个不同来源的栽培大豆和17个野生大豆资源杂交所获得的103个杂交组合中有8个组合的后代出现不育株,经进一步的正反交和回交试验,发现来源于山西的野生材料N23168和来源于湖北的栽培品种N21566具不育细胞质。另外,对10个不明其细胞质育性的雄性不育材料用原亲代(父本)及NJCMS1A保持系N2899、N21249进行授粉、杂交、回交鉴定,发现来自N2877(栽培)×N20019(野生)的CAms、N1642(栽培)×N23719(栽培)的AYms和野生型不育突变体WSms的不育性受质核互作基因控制。利用测验种分别与上述N23168、N21566、N2877、N1642、WSms等5个具不育细胞质的亲本材料回交,选育出新质核互作雄性不育材料NJCMS(N23168/N21249)、NJCMS(N21566/N21249)、NJCMS(N2877/N21249)、NJCMS(N1642/N23719)、NJCMS(WSms/N21249)。观察发现不同细胞质来源的不育种质均雄性完全不育,但花药、花粉形态不同,NJCMS(WSms/N21249)BC4F1和NJCMS(N23168/N21249)BC1F1不育株败育最彻底,而5个不育种质与5个恢/保品种杂交F1的育性表现不同,N8855、N21566、N2877来源的不育种质具有相同的恢保关系,与N1642和WSms来源的不育种质的恢保关系不同。新发掘的质核互作雄性不育种质为大豆杂种优势利用研究拓展了材料,也表明栽培大豆与野生大豆资源中不育细胞质并不少见,利用合适的不育核背景可筛选出新的不育细胞质。

There are still problems in the utilization of heterosis in soybean due to the difficulties in pollination or outcrossing in increasing seeds of male-sterile lines and producing hybrid seeds even the three line system （ male-sterile line, maintainer line and restorer line） has been established already. One of the ways in solving the problems is to find new male-sterile cytoplasm as well as the corresponding nuclear male-sterile genes. On the other hand, intensive use of a single source of male-sterile cytoplasm can cause genetic vtdnerability and may be disastrous as with the case of Texas cytoplasm in maize. Therefore, it is necessary to diversify the sources of male-sterile cytoplasm. The present paper deals with the results of identification and evaluation of new sources of male-sterile cytoplasm in soybean. Total 71 cultivated and 17 annual wild soybean accessions used as female parents were crossed with four testers （known maintainers of NJCMS1A） to screen for potential new male-sterile cytoplasm. Among 103 crosses, eight ones with N8855.1, N21566, N23168, NG99- 893 and N24085 as female parents appeared to have male-sterile plants in their progenies. The wild soybean accession N23168 from Shanxi Province and cultivated landrace N21566 were further confirmed to have male-sterile cytoplasm according to the male fertility performance of backcrosses and reciprocal crosses with N21249. In addition, the male-sterile plants of 10 newly selected lines with unknown cytoplasmic fertility were pollinated with N2899, N21249 （maintainers of NJCMSIA）, as well as original male parents to generate F1 and BC1F1 populations which showed that the male fertility ofCAms （from N2877 × N20019）, AYms （from N1642 × N23719） and WSms （possibly wild mutant） performed cytoplasmic- nuclear male-sterile. From the above, five CMS lines NJCMS（N23168 /N21249）, N.ICMS3A（N21566/N21249）, NJCMS （N2877/N21249）, NJCMS（N1642/N23719） and NJCMS（WSms/N21249） were developed, respectively. They appeared completely male-sterile with different morphological characters in pollen and anther. When all the five new CMS lines were crossed with five restorers/maintainers （male parent）, those derived from the cytoplasm sources of N8855, N21566 and N2877 had similar F1 fertility performance （restorer/maintainer relationship）, but differed from those derived from AYms and WSms male-sterile lines. The results also implied that there might exist a certain frequency of male-sterile cytoplasm in Glycine max and G. soja gennplasm and that to screen out new CMS system might be feasible through selecting maintainers with suitable nuclear background as testers to test the gennplasm collection. The obtained new male-sterile cytoplasm sources can be used to develop new male-sterile lines for the improvement of hybrid soybean production system.