Genetic Analysis and Primary Mapping of pms4, a Photoperiod-Sensitive Genic Male Sterility Gene in Rice (Oryza sativa)

To understand the genetic characteristics of a new photoperiod-sensitive genic male sterile line Mian 9S, some reciprocal crosses were made between Mian 9S and six indica rice materials, Yangdao 6, Luhui 602, Shuihui 527, Mianhui 725, Fuhui 838 and Yixiang 1B. Genetic analysis results suggested that the photoperiod-sensitive genic male sterility （PGMS） of Mian 9S was controlled by a single recessive nuclear gene. Thus, the F2 population derived from the cross of Yangdao 6/Mian 9S was used to map the PGMS gene in Mian 9S. By using SSR markers, the PGMS gene of Mian 9S was mapped on one side of the markers, RM6659 and RM1305, on rice chromosome 4, with the genetic distances of 3.0 cM and 3.5 cM, respectively. The gene was a novel PGMS gene and designated tentatively as pms4. In addition, the application of the pms4 gene was discussed.

Mapping of a gene for photoperiod-sensitive genic male sterility in Nongken 58s on chromosome 5 of rice

A photoperiod-sensitive genic male sterile (PGMS) rice was found in 1973 as a spontaneous mutant of Nongken 58, a japonica variety. Pollen fertility of Nongken 58s (N58s) is completely sterile when grown under long-day conditions, whereas fertile under short-day conditions. This PGMS was found to be controlled by one or two recessive gene(s), of which one gene(pms)was linked to a marker gene(d-1) on chromosome 5. In order to identify a more precise location of the pms, we analyzed the populations of BCFand BCFof N58s//N58s/KL211(v-10, virescent) and N58s//N58s/KL520 (gh-1, gold hull). The marker genes v-10 and gh-1 are located on the flanking region of d-1. The F, plants of two crosses were fertile. The number of fertile and sterile individuals in BCFfit

Characterization and fine mapping of RTMS10, a semi-dominant reverse thermo-sensitive genic male sterile locus in rice

The discovery and application of environment-sensitive genic male sterile(EGMS) rice germplasm provide an easy method for hybrid rice breeding and have made great contributions to hybrid rice production. Typically, the photoperiod-and thermosensitive GMS(P/TGMS) lines utilized in two-line hybrid systems are male sterile under long day or/and high temperature but fertile under short day or/and low temperature conditions. However, Yannong S(Yn S), a reverse TGMS(rTGMS) line, is sterile under low temperature(<29℃) and fertile under high temperature(>29.5℃). Here, we report a genetic study on the rTGMS trait in Yn S. Interestingly, the F1 plants of the cross between Yn S and a cultivar, L422, were male sterile at 22℃ and completely fertile at 27℃. Moreover, the segregation ratio of fertile and sterile individuals in Yn S/L422 F2 populations changed from 1:3.05 to 2.95:1 when the ambient temperature increased, showing that the rTGMS trait exhibits semidominance in Yn S. We further found a locus on chromosome 10, termed RTMS10, which controls the rTGMS trait in Yn S. We then finely mapped RTMS10 to a ~68 kb interval between markers ID13116 and ID1318 by Yn S/L422 BC6 F2 populations. A near iso-genic line(NIL) NL1 from the BC6 F3 generation was developed and the pollen of NL1 became abnormal from the meiosis stage under low temperature. In summary, we identified an rTGMS locus, RTMS10, and provided co-segregated markers, which could help to accelerate molecular breeding of rTGMS lines and better understand the rTGMS trait in rice.

Studies on the Photoperiod Sensitive Characters of Male Fertility Alteration of Peiai64S' Main Male Genic Sterile Gene

Peiai64S, an indica male sterile rice with a male fertility alteration under different environments, is selected from the offspring of indica rice crossed with Nongken58S. Nongken58S, a japonica pho-toperiod sensitive genie male sterile rice (PGMS), deriving from a natural mutant plant individual of normal japonica rice variety, Nongken58, is used as a male sterile gene donor of Peiai64S. But Peiai64S is not a typical PGMS rice, the male fertility is sensitive to temperature just as thermo-sensitive genie male sterile rice (TGMS). We have selected typical PGMS plants in F2 population of Peiai64S× Nongken58, whose ratio of fertile plants to sterile plants is nearly 3:1. The sterility inheritance conformed to one pair of gene segregation model. The result indicates the main male sterile gene in Peiai64S is not other than the PGMS gene, and comes from Nongken58S. The genetic background affects effective expression of the PGMS gene. This suggests that we ought to focus on optimizing the genetic background of the PGMS gene in PGMS rice breeding, and select an ideal genetic background as a transgenic background in molecular breeding.

pms3 is the locus causing the original photoperiod-sensitive male sterility mutation of‘Nongken 58S'

Photoperiod-sensitive genic male sterile (PSGMS) rice is a very useful germplasm for hybrid rice development. It was first found as a spontaneous mutant in a japonica cultivar ’Nongken 58’. pms3 on chromosome 12 was determined to be the locus where the original PSGMS mutation occurred, changing the normal cultivar Nongken 58 to PSGMS Nongken 58S. Large amounts of RAPD and AFLP analyses were also conducted for the fine mapping of the pms3 genomic region, which resulted in 4 molecular markers linked to pms3. Although these markers somewhat increased the marker density of this region, the pms3 locus is still located in a marker-sparse region.

大豆花药优势表达基因GmFLA22a调控雄性育性的功能研究

我国大豆对外依赖度高,加速提高大豆产量是目前亟需解决的问题。利用杂种优势是大幅提高作物产量的有效途径之一,近年来基于隐性核不育基因开发的智能雄性不育系统,为快速利用大豆杂种优势提供了可能。但是,大豆雄性不育基因研究相对滞后。本研究基于课题组大豆花器官转录组数据,筛选到在大豆早期花药中优势表达基因GmFLA22a,编码含有FAS1结构域的成束状阿拉伯半乳糖蛋白,亚细胞定位表明其可能在内质网中发挥功能。利用基因编辑技术获得Gmfla22a突变体,突变体植株在营养生长阶段与对照组相比没有明显差异,但在生殖生长阶段表现为结实率显著降低。Gmfla22a突变体花粉活力和花粉萌发率均无明显异常,组织切片并染色观察发现,突变体植株花药室壁增厚,花粉粒释放延迟、不完全,这可能是导致Gmfla22a结实率降低的原因。综上,本研究初步揭示GmFLA22a可能参与调控大豆雄性育性,为深入揭示其分子功能提供重要遗传材料,同时为大豆杂种优势利用提供基因资源和理论依据。

一个恢复力受单基因控制的水稻CMS育性回复突变体

利用￣（６０）Ｃｏ－γ射线对具有印尼水田谷细胞质的籼稻细胞质雄性不育系Ⅱ－３２Ａ干种子进行诱变处理，获得了一育性回复突变体Ｔ２４。育性基因未纯合的突变体分离出可育株和完全不育株，比例为３∶１；其与Ⅱ－３２Ａ和珍汕９７Ａ测交，Ｆ１代分离出１∶１的可育株和不育株。育性稳定株系与Ⅱ－３２Ａ和珍汕９７Ａ杂交，Ｆ２分离成３∶１的可育株和不育株。表明其育性回复是由一对基因显性突变所致。这一突变体对不育系的育性恢复机制不同于明恢６３、２０９６４等恢复系，后者表现为两对显性恢复基因作用。未观察到Ｔ２４与亲本Ⅱ－３２Ａ除育性以外的其他性状的差异，因而两者构成育性恢复基因的近等基因系。本文还对不育系育性回复类型和Ｔ２４的理论意义与育种价值进行了讨论。

茄子反向温敏雄性不育系可溶性糖含量及相关基因表达分析

为揭示茄子反向温敏核雄性不育(rTGMS)发生与糖类代谢的关系,以茄子rTGMS系‘05ms’及温度不敏感系‘S63’为试材,对不育期和可育期的叶片及花蕾的可溶性糖含量进行比较,结果表明,‘05ms’在不育和可育时期叶片和花蕾中的可溶性糖含量均显著低于‘S63’;进一步对‘05ms’花蕾进行转录组测序及对其糖类代谢相关途径进行分析,发现差异表达基因主要富集在3个通路:淀粉和蔗糖代谢、糖酵解/糖异生和氨基糖和核苷酸糖代谢,其中淀粉和蔗糖代谢通路的差异基因最多且大部分在低温条件表达下调,主要影响了葡萄糖和半乳糖醛酸的合成。此结果初步揭示了茄子反向温敏雄性不育系中糖类代谢响应温度变化的特点,为茄子雄性不育杂交育种提供理论依据。

野栽远缘杂交来源的反向温敏核雄性不育系不育性遗传研究

利用3个来源于野生稻与栽培稻杂交后代的反向温敏不育系R6S、N13S、Tb7S为材料,开展了反向温敏不育系不育性遗传研究,结果表明反向温敏不育系N13S的育性是细胞核内1对隐性基因控制的;Tb7S的育性是受隐性核基因控制的,F2代的育性分离比为9∶7,不育性状表现为2对基因的独立遗传;R6S的F2代育性分离比为37∶27,受细胞核内的3个隐性基因位点分别位于不同染色体上而通过互补作用的独立遗传.为进一步分离、定位及克隆有关这些反向温敏不育基因及发展分子标记辅助选择选育反向温敏不育系奠定了良好的遗传学基础.

Selection of Submergence Tolerant Homozygous Line by STS Marker and Twice Submergence Stress

One sequence tagged site marker Subl-1 and twice submergence stress method were used in selection of submergence tolerant homozygous line from Sub-lBS, a submergence tolerant, bentazon sensitive and photoperiod-sensitive and/or thermo-sensitive genic male sterile line that developed by our laboratory. The results revealed that the original Sub-lBS was heterozygous in SublA-1 locus even though it was identical in almost all of agronomical traits and the segregation of SublA-1 was in accordance with Mendelian law based on chi-square test. And then the original Sub-IBS was divided into two groups： one was ofSublA-1 introgression and the other was not; and the two groups were tested by twice submergence stress method. After the first submergence stress that lasted for 12 d, the average plant heights were significant difference at the 1% level between the two groups. After recovery for 10 d, the second submergence stress sustained for 18 d was carried on; and the group with SublA-1 gene was found apparently tolerant than the other group in submergence tolerance.

水稻短光敏不育基因(rpms4)的遗传分析及初步定位

为了深入研究水稻短光敏不育基因,以D38S为母本,华占为父本构建了一个F_2分离群体,对短光敏不育基因控制的遗传规律进行分析。利用集团分离分析法(bulked segregant analysis,BSA)筛选多态性SSR标记,并在多态性标记附近增加标记引物筛选,将获得所有多态性SSR标记对含有248个单株的D38S×华占杂交得到F_2群体进行定位分析。D38S×华占的F_1代植株在南昌早季镜检花粉育性表现正常,自然结实率也正常。对248个F_2群体单株进行育性调查,统计短光可育株与短光不育株分离比,发现短光可育株与短光不育株数分离比符合3:1的分离比,因此可以推测D38S的短光敏不育性状遗传模式符合受1对隐性核基因控制模式。该研究利用集团分离分析法(BSA)从均匀覆盖水稻染色体基因组的3600对SSR中筛选到7对与该不育基因连锁的标记。利用D38S×华占的F_2群体和7对SSR标记,将短光敏不育基因定位于水稻1号染色体,位于标记RM3442与RM6339之间,遗传图距均为1.2 cM,将该短光敏不育新基因命名为rpms4。本研究为进一步精细定位和克隆rpms4提供了科学依据。