Analysis of genic male sterility in Brassica oleracea

Summary The male sterility system MS-1 of Brassica oleracea was studied in order to elucidate if nucleo-cytoplasmic interactions determine this system. Crosses of male sterile MS-1 genotypes with heterozygous MS-5 genotypes gave fully fertile F₁ progenies. Selfing of seven F₁ plants resulted in five F₂ populations showing a 9:7 segregation ratio and two a 3:1 ratio for fertile and male sterile plants. Two F₂ progenies deviated from the expected 9:7 or 3:1 segregation ratios for fertile and male sterile plants. Thermosensitivity and distortion of the meiosis are suggested as the causal factors underlying the deviation of the segregation ratios. It was concluded that nuclear factors determine the male sterility in the MS-1 system, because the presence of a nucleocytoplasmic interaction in this system should have given only a 3:1 segregation ratio for fertile and male sterile plants in the F₂ generation.     

Chloroplast-DNA variation in the wild and cultivated olives (Olea europaea L.) of Morocco

The male sterile plants that segregated in a BC₅F₂ of `C. sericeus × C. cajan var. TT-5' population were maintained by sib mating. The male sterile plants were crossed with ICPL-85012.Approximately 50% of the F₁ plants were sterile. F₂ plants derived from the fertile F₁ plants did not segregate for male sterility. The reciprocal hybrid i.e. ICPL-85012 × Fertile derivatives from C. sericeus × TT-5, did not express male sterility. However, among the 12 F₂ plant to row progenies, two segregated 25% male sterile plants and remaining 10 did not segregate. The segregation pattern in subsequent progenies revealed that the sterility was under control of a single recessive allele. Studies on the backcross and their BC₁F₂ and BC₁F₃progenies revealed another sterility gene which was found to be dominant in inheritance. This paper shows that what was thought to be cytoplasmic male sterility from C. sericeus cytoplasm is actually a single dominant gene possibly acting in concert with a single recessive gene to mimic cytoplasmic male sterility. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inheritance of male sterility mutations induced in haploid sorghum tissue culture

Summary A high frequency of male sterile mutants regeneration was shown in callus cultures derived from leaves and panicles of haploid sorghum (Ms_c1, A1 cytoplasm) and a spontaneous autodiploid obtained from this haploid. The cultures derived from the embryos of this autodiploid yielded significantly fewer mutants. Absolutely or partially male sterile mutants appeared among the regenerants or in the progeny of fertile regenerants. In the self-fertilized progenies of partially male sterile mutants and in the hybrids of sterile mutants with autodiploid line (i.e. under one and the same nuclear genome) male sterility mutations were inherited as cytoplasmic. Non-Mendelian segregation of sterile, partially male sterile and fertile plants was observed in these progenies. Partially male sterile plants were characterized by somatic segregation of male sterility genetic factors. In test-crosses with some CMS A1 fertility restorers, mutations were manifested as nuclear recessive while with others as nuclear dominant. These differences are supposed to be the result of interaction of fertility restorer genes of these testers with the novel cytoplasm. Male sterility mutations accompanied with female sterility were inherited as nuclear recessives.Abbreviations f fertile - ps partially male sterile - s male sterile plants     

Cytological and genetical studies of a male sterile celery

Summary The inheritance and nature fo male sterility of a cerley (Apium graveolens L.) strain (MS1) is reported. Male sterility in MS1 is determined by a a recessive genotype for a single locus. Tests for linkage with the isozyme chromosome markers SDH-1 and PGM-1 were negative. MS1 male sterility was associated with a defective tapetum characterized by prominent vacuoles and premature degeneration. The stamens in the male sterile strain persisted in the flowers up to stigma receptivity, while in the male fertile plants they dropped before style expansion. The male sterile flowers produced normal amounts of nectar, resulting in cross pollination by various species of pollinators. It was estimated that the sterile strain produced 30% less seed than normal male fertile. Its possible use for hybrid celery seed production is discussed.Research supported by grants from the California Celery Research Board and BARD I-483-82.     

Genetic analysis of male sterility in rice mutants with environmentally influenced levels of fertility

Summary Twenty-six male sterile plants grown in the field were recovered in the M7 generation from ethyl methane sulfonate-treated material of the rice cultivar M-201. Fertility increased five-fold when ratooned plants from the field were grown in a growth chamber with a 12 hour daylength. Crosses between mutant and normal fertile cultivars produced fertile F₁ plants. Female fertility was normal as judged by percent seed set from unbagged panicles of parental and recombinant lines. Transgressive segregation for fertility was observed for all crosses in the F₂ and F₃ generations. Five of 37 F₃ male sterile plants showed moderate levels of seed fertility under winter greenhouse conditions and reduced seed set when transplanted to summer field plots. Fertility data from reciprocal crosses suggested cytoplasmic factors had little or no effect on levels of male sterility in the mutant lines. Chi-squared analyses of F₂ and F₃ generation results indicated male sterility of the mutants is conditioned by two nuclear genes with epistatic effects.     

棉花核不育系豫98-8A育性遗传分析

为了阐明1999年从转基因后代遗传群体中发现的1株雄性不育植株不育基因的遗传规律及其与现有不育基因的等位性,采用表型观察测量,以及经典的自交和测交手段,研究了该不育材料败育性状的遗传规律。花器官形态特征调查表明：不育株花柱长和花柱外露长度均明显高于同质系的正常可育株,而每朵花的子房直径及花药数量没有明显差异。遗传分析表明：杂合体可育株自交,后代不育株与可育株呈3:1分离,不育株与杂合姊妹可育株测交,不育株与可育株呈1:1分离,表明该核不育材料受隐性单位点控制;与阆A(msc1)、洞A(msc3)等育性位点杂合可育株分别杂交,其F1代单株育性均得到恢复。由其F1代产生的F1:2家系中均出现不育株与可育株呈1:3和7:9两个育性分离群体,表明该材料败育基因为不同于阆A、洞A的不育基因位点。     

Cytoplasmic-genetic male sterility in radish (Raphanus sativus L.). Identification of maintainers,inheritance of male sterility and effect of environmental factors

Summary Research has been carried out on identification of maintainers for cytoplasmic-genetic male sterile lines in Japanese and European radish, on the mode of inheritance of male sterility and on the effect of environmental factors on the expression of this character.In a Japanese radish population and in most early European radish populations maintainers were found in high frequency. Segregations for male sterility in full-sib families, obtained by crossing male sterile and male fertile plants, and in backcross generations, indicated that male sterility is probably determined by one dominant and two recessive independently acting genes, but also minor genes may be involved.The expression of male sterility was not affected by seasonal influences. In some populations a reversible temperature effect was found, most ms plants occurred at 10, 14 and 26°C and most mf plants at 17 and 20°C.     

A male sterile line with dominant gene (Ms) in cabbage (Brassica oleracea var. capitata) and its utilization for hybrid seed production

A male sterile plant, 79-399-3, was identified from a spring cabbage line 79-399 in 1979. Light-microscopic studies with paraffin section indicated that meiotic division stopped at the tetrad stage. The ratio of male sterile plants to fertile plants in the progenies of test crosses was 1:1 in five experiments conducted in 1982 and 1991–1994. However, some male sterile plants were sensitive and developed a very low number of viable pollen grains. When sensitive male sterile plants were selfed, the progenies segregated into male sterile and fertile plants at a ratio of 3:1. The male sterile plants from selfing of sensitive male sterile plants were propagated by tissue culture and crossed with different inbred lines. From the progenies of the crosses, populations with 100% male sterile plants were observed. The results indicated that homozygous dominant male sterile (MsMs) plants segregated from the selfed progenies. Populations with 100% male sterile plants and stable male sterility were developed as male sterile lines. Several favorable combinations were also selected by crossing the male sterile lines with inbred lines with high combining ability for desirable horticultural characters. This revised version was published online in July 2006 with corrections to the Cover Date.     

通过组织培养获得棉花不育株

棉花（ＧｏｓｓｐｉｕｍｈｉｒｓｕｔｕｍＬ．）体细胞培养获得的再生植株中存在很大差异,其中育性变异表现最突出,在１９９０～１９９１年培养再生的植株中发现９个不育株,其中１株雌雄全不育,形态上表现高大紧凑,花器小,畸形,柱头四裂,电镜观察表明其它粉粒空瘪,内容物少,另２株为雄性不育,电镜观察发现其花粉粒外壁发育不良。用鄂荆１号做父本与其杂交,Ｆ１代值株均不育,鄂荆１号回交ＢＣ１不育株与可育株呈１：１分     

Chromosomal monogenic dominant male sterility in chinese cabbage (Brassica rapa supbs. pekinensis (Lour.) hanelt)

Summary Strong indication was found for the existence of a chromosal monogenic dominant male sterility-gene in chenese cabbage. This source of male sterility can be of practical use for the production of hybrid varieties. A pronounced drawback is the required removal, in the breeding and seed production stage, of the approximately 50% male fertile plants from each offspring of male sterile plants. Fortunately this removal is facilitated by the penomenon of apical dominace in the flowering process in the whole Brassica rapa taxon. Moreover an advantage of dominant monogenic male sterility is its easy and rapid introduction into all available genotypes of chinese cabbage.     

A new source of cytoplasmic male sterility in sunflower

Summary Interspecific substitutions of the nucleus of Helianthus annuus (2n=34) cv. Saturn into the cytoplasm of H. petiolaris (2n=34) by successive backcrossing, resulted in progenies with indehiscent anthers containing white, rather than normal yellow, pollen. Further backcrossing by cv. Saturn failed to restore pollen shed, suggesting that the male sterility was cytoplasmic. In vivo germination tests of pollen from 23 such plants from eight BC₅ lines, indicated complete pollen sterility for 14 plants, but normal seed set, suggesting that female fertility was not affected. Meiosis in all plants examined was normal.Crosses between seven sources of pollen-fertility restorer, one collection of wild H. annuus, and an existing source of cytoplasmic male sterility, resulted in a high frequency of plants with normal pollen shed in all F₁ progenies. However, no normal pollen shed was evident in F₁ progenies for similar crosses between BC₅ male-steriles and three of the seven restorer sources, nor for the single wild H. annuus evaluated. The foregoing suggests that the backcross substitution lines are a new source of cytoplasmic male sterility. The inheritance of restoration of pollen shed was complex and not fully elucidated. Some data suggested that two independent, complementary, dominant genes were required, but others indicated two to three independent, dominant genes.     

Effects of low temperature storage on the pollen of Brassica campestris,B. oleracea and B. napus

Summary Four indica cultivars viz. Kalinga-I, Ptb. 10, IR 27280-13-3-3-3 and Co. 41 were found to possess male sterile cytoplasm with fertility restoring genes while the cultivar Krishna was found to maintain the male sterility in all the cases. All the plants in the F₁ of Kalinga-I × Krishna were observed to be completely male sterile and continued to show complete pollen sterility in subsequent backcross generations when backcrossed with recurring pollen parent, Krishna. Thus, it was posible to develop a new cytoplasmic-genetic male sterile line in indica rice (Krishna A) with Kalinga-I male sterile cytoplasm and this male sterile cytoplasm was found to be genetically different from others. Further, the newly developed male sterile line (Krishna A) was observed to be tolerant for low temperature at seedling stage.     

Digenic nature of male sterility in pepper (Capsicum annuum L.)

Summary A cross was made between two nearly isogenic lines differing for male sterility genes, viz. ms₁ms₁Ms₂Ms₂ s Ms₁Ms₁Ms₂ms₂. F₁ plants yielded F₂ populations which segregated either in 3:1 or 9:7 ratios of fertile vs male sterile individuals. Test crosses between male sterile and male fertile sibs in the 9:7 segregating populations provided a few lines in which most of the progenies were male sterile. A 3:1 ratio model of male steriles vs fertiles is suggested and the value of the system is discussed.Contribution A.R.O. Agricultural Research Organization, The Volcani Center, Bet Dagan 50 250, Israel No. 3703-E, 1992 series.     

中国首例燕麦雄性不育的发现及遗传鉴定

对1994年发现的我国首例燕麦雄性不育材料进行了特征特性的观察和细胞学鉴定、以及不育性遗传的研究,结果表明:(1)该材料不育度为100%,属“无花粉型”的雄性不育,不育株小抱子败育发生在四分体形成后期到花粉粒形成早期阶段。(2)不育株与不同品种测交的F1代,6个组合表现育性恢复,2个组合出现一些完全不育株;恢复育性的植     

水稻三明显性核不育基因的初步鉴定

2001年在福建省尤溪县西城镇凤元村进行两系核不育系育性鉴定时, 在SE21S/Basmati 370组合编号为S221的800多株F₂代分离群体中发现1株与其他不育株的花粉败育形态不同的植株。经测交、回交、姐妹交的后代育性分离调查, 不育株与可育株呈1︰1分离, 以不育株为母本与普通品种配制杂交组合, 其后代育性呈1︰1分离, 可育株后代分离不出不育株, 表明S221不育性受核内1对显性不育基因控制。     

Inheritance of genetic malesterility in Pennisetum americanum (L.) Leeke

Summary A spontaneously occurring male sterile condition was located in an inbred line Vg 272 of Pennisetum americanum. Male sterility was inherited as a monogenic recessive condition and showed independent assortment with hairy leaf surface phenotype. Transfer of male sterile allele to inbreds Vg 212 and IP 482 revealed no cytoplasmic effects on the expression of male sterility. Stigmas of the male sterile plants were found to possess the same amount of receptivity upto three days with normal seed set, upto six days with reduced seed set and almost with nil receptivity on the seventh day.     

苜蓿雄性不育系及其回交后代同工酶分析

采用聚丙烯酰胺凝胶垂直板电泳技术对苜蓿雄性不育系及其回交后代进行过氧化物酶(POD)、酯酶(EST)同工酶分析。结果表明:(1)苜蓿雄性不育系及其回交后代叶的POD同工酶在现蕾期和开花期的酶带数较返青期多。返青期的酶活性较现蕾期和开花期强;MS-4及其回交后代叶的EST同工酶活性变化规律与POD同工酶谱表现相似;(2)在花发育的不同时期,花蕾为绿色时期时的POD同工酶酶活性最强,MS-4及其回交后代小花的EST同_T-酶酶带数较叶的多。刚开过的小花EST同工酶酶活性最强,F1、BC1代不育株都出现了母本MS-4所具有的POD、EST特征酶带;(3)从MS-4回交后代中所选育的不育株的POD和EST同工酶谱明显偏向于轮回亲本MS-4,说明通过回交使MS-4的某些性状在回交后代中进一步得到表现,因此,可以初步认定原不育系Ms4的不育性是可遗传的。     

Estimation of hybrid seed production and efficient pollen flow using insect pollination of male sterile soybeans in caged plots

The aptitude of leafcutter bees to pollinate male sterile soybean plants (ms2 gene) in caged plots was evaluated in four experiments from both quantitative and qualitative points of view. The m.s. plant seed set was satisfactory: on average, it represented 60% of the male fertile isogenic seed set (with a range between 44 and 69%). The lower yield of m.s. plants was linked with a smaller number of fertile reproductive nodes. The efficient pollen flow was observed over the flowering period with both morphological and electrophoretic markers. Insect behaviour was not influenced by flower colour. Differences between flowering duration of pollen donors appear to be the major factor inducing unbalanced populations. The interest of this technique as a tool for dynamic management of the genetic variation in populations or for hybrid seed production is discussed.     

Natural male sterile mutant in hot chilli (Capsicum annuum L.)

Summary A natural male sterile mutant was recovered from the normal population of chilli cv. CA 452-1. The male sterility in the mutant was governed by a single recessive gene ms. The excessive vegetative growth provided easy identification of male sterile plants in the seedling stage. The plant was found to be promising for hybrid seed production.     

Male sterility in some cole crops

Some male sterile plants were found in seed fields of cauliflower, Brussels sprouts and white cabbage. In all 3 crops the male sterile flowers were characterized by shorter stamens and shrivelled anthers. Male sterility did not seem to be greatly influenced by the environment.In cauliflower male sterility is determined by 1 recessive factor. In Brussels sprouts this characteristic also depends on recessive factors. In this crop, however, the mode of inheritance is much more complicated. In addition to completely male sterile plants there were also partially male sterile plants of Brussels sprouts.Two plants of white cabbage were found to be male and female sterile.