红麻细胞质雄性不育系小孢子败育的细胞学观察

对同质异核的红麻细胞质雄性不育系L23A和K03A的小孢子发生和败育过程进行了细胞学比较观察。结果发现,2个不育系的败育过程有一定的相似性,败育都发生在四分体及单核小孢子时期;单核小孢子外壁发育都出现异常,小孢子原生质收缩变形或解体;花药壁的中层延迟解体,绒毡层出现细胞融合、液泡化、提前脱离药壁进入药室和过早解体等异常行为。但两者败育的过程又有一定差异,单核早中期,L23A的小孢子发育基本正常,而K03A的小孢子外壁发育不良,壁薄且质脆、易破损,刺稀少细小;L23A的小孢子外壁在单核后期解体成为念珠状,而K03A的小孢子外壁在发育过程中破损、逐渐溶解;小孢子外壁解体过程中,L23A的小孢子原生质收缩为核质不分的一团,而K03A的小孢子原生质逐渐解体。     

核不育芝麻小孢子败育机理的细胞学研究

核不育芝麻小孢子败育发生在四分体形成之后的无液泡小孢子期,败育在很短的时间内完成。败育前小孢子大量液泡化,其线粒体异常膨大与质体的基质化可作为小孢子开始败育的标志。败育小孢子缺少花粉外壁上的覆盖层。芝麻花药绒毡层的异常,包括有机物贮量的降低;细胞内含物的异位分布及迅速减少与消失;不能及时或缺乏分泌胼胝质     

油菜温敏雄性不育系373S的选育

发现和选育新型光温敏雄性不育材料,有利于深入揭示植物雄性不育的发生机制,丰富油菜杂种优势利用的方法。笔者报道一种新发现的环境敏感雄性不育系373S的选育过程及其育性随温度、日长的变化基本规律。2002年在一个天然雄性不育群体后代中发现1株嵌合不育株,经过连续自交,育成环境敏感不育系373S。2004—2006年在陕西杨凌进行分期播种试验,并进行了温度、光照脉冲处理试验。结果表明：373S是主要对温度敏感的雄性不育系,低温可育而高温不育,开花前2~9d的平均温度对育性影响显著,而日长对育性影响不明显,花蕾长度约2~3mm是育性转换的敏感时期。用一系列品种与373S测交,F1均为100%可育,在F2代温敏不育株出现几率很高,可以达到7.1%~14.6%。进一步精确分析373S光温反应特征、改良其农艺及品质性状、寻找适宜制种生态区的工作正在进行当中。     

春萝卜雄性不育系4-05A小孢子败育的细胞学观察

为了确定其花粉败育的时期和细胞学特点,采用石蜡切片法,对春萝卜雄性不育系4-05A及其保持系4-05B小孢子发生和花粉发育过程进行观察、比较。结果表明:不育系和保持系小孢子母细胞都能正常进行减数分裂,四分体可以释放出小孢子,不育系4-05A败育发生在单核靠边期,解体后的绒毡层原生质团急剧而彻底地进入花粉囊,渗入花粉母细胞周围,并与花粉母细胞黏连在一起。     

甘蓝型油菜光、温敏雄性不育系Huiyou50S花粉败育的细胞学观察

Huiyou50S是从甘蓝型油菜品种汇油50中发现的半不育株选育而成的光、温敏雄性不育系,育性受隐性核基因控制,在高温、长光周期下不育而在低温、短光周期条件下可育。本文通过半薄树脂切片、扫描电镜、花粉压片染色、花药整体透明方法对Huiyou50S及其近等基因系Huiyou50F的花药发育过程及花粉形态观察比较。结果表明, Huiyou50S的花药造孢细胞、花粉母细胞、减数分裂、四分体阶段均正常,在单核期出现明显异常,虽然能形成花粉壁,但小孢子细胞质收缩、解体,最终只剩余空瘪的花粉壳; Huiyou50S的花药绒毡层在单核后期提前降解,绒毡层解体速度快于可育株Huiyou50F。Huiyou50S的小孢子的完全败育主要发生在单核时期,绒毡层发育与小孢子异常有某种关联,该结论为油菜光、温敏雄性不育类型划分及育种应用提供了依据。     

高粱不育系小花败育的原因与预防措施

高粱不育系小花败育直接影响着单位面积的种子产量 ,相应地增加了种子生产成本 ,影响着种子生产户的积极性。因此 ,对小花败育的预防显得十分重要。1　高粱不育系小花败育的现象及原因1.1　高粱不育系小花败育现象 :小花败育就是高粱雄性不育系雄蕊、雌蕊发育不正常 ,不完全 ,不能授粉结实。生产上一般表现为子房变小 ,花柱变短 ,羽毛状柱头发达 ,花药秕瘦 ,抽雄后颖壳白色 ,护颖软而不能开张 ,柱头根本不能伸出。发生的部位不定 ,有的在穗子顶端 ,有的在穗子中部、下部或一个侧面 ,败育程度在0～ 10 0 %之间。1.2　引起小花败育的原因 :引…     

玉米细胞质不育系JnA的分组鉴定和花粉败育观察

自Rhoades(1930)首次发现班米雄性不育(CMS)材料后[1],人们又陆续发现了一百多种班米CMS材料,其应用给生产上带来了巨大的经济效益.     

芝麻核雄性不育系ms86-1小孢子败育过程的超微结构

运用透射电子显微镜对芝麻核雄性不育系ms86-1的可育和不育花药进行了超微结构的比较观察。根据小孢子的细胞学形态特征,将芝麻花粉发育过程划分为小孢子母细胞形成期、减数分裂期、四分体期、单核小孢子早期、单核小孢子中期、单核小孢子晚期、花粉成熟期7个时期。对比观察表明芝麻核雄性不育的败育迹象起始于小孢子母细胞形成期,并伴随着进一步发育,败育现象逐渐明显,小孢子母细胞形成期小孢子母细胞壁形状不规则;减数分裂期小孢子母细胞壁严重扭曲变形,质膜外缺少早期外壁成分--原基粒棒;四分体期胼胝质壁外沉积物异常,呈绒毛状;四分体解体后形成畸形小孢子,孢子外壁不健全,绒毡层异常肥厚、降解延迟,释放极少量的畸形乌氏体;随后小孢子愈发皱缩,胞质凝集,内含物减少并逐渐凝聚成一团电子致密物质,最终走向完全败育。本研究揭示了不育小孢子的败育过程和败育特征,为深入研究芝麻核雄性不育败育机理奠定了基础。     

高粱不育系雌性小花败育原因及解决办法

高粱不育系是配制高粱杂交种的母本材料。在制种时不育系常常发生雌性小花败育不结实现象,轻者降低制种产量,重者造成绝收。为什么会发生雌性小花败育呢?我们通过大量的生产实践和科学试验研究分析,发现造成不育系雌性小花败育的原因有以下三方面:     

甘蓝型油菜细胞质雄性不育系105A花药败育的细胞学观察

旨在了解并揭示不育系105A的花粉败育时期和细胞学特征,为进一步正确认识细胞质雄性不育系分子机制提供必要参考依据。采用石蜡制片法,对甘蓝型油菜杂交种‘青杂5号’的雄性不育系105A及其恢复系1831R的小孢子发生和花药发育过程进行观察,以确定其花粉败育的时期和细胞学特点。研究结果表明,在不育系105A花药败育过程中,一部分发生于造孢细胞时期,属于无花粉囊败育型;另一部分发生于单核晚期,属于单核败育型,其特点为单核晚期绒毡层细胞膨大向小孢子靠近,并逐步降解,其破裂胞质退化残余物侵入药室,与小孢子混合粘连在一起,甚至有些绒毡层细胞整块脱落,成为染色很深的团块状物质,占据药室一部分空间,最终小孢子降解,花药败育。     

甘蓝型油菜温敏细胞核雄性不育系160S花药败育的形态学特征和细胞学研究

明确甘蓝型油菜温敏核雄性不育系160S花器形态变化、花药败育的时期和细胞学特征,初步探究败育的原因,为深入研究不育系160S的内在分子调控机制提供理论基础,也对其在油菜两系杂交育种中的实际应用具有指导意义。本研究在15℃和28℃条件下培养试验材料160S,利用体式显微镜分别观察花发育形态特征;采用醋酸洋红染色方法观察各时期小孢子发育形态;通过石蜡切片和苏木精-伊红染色对可育植株(MaleFertile/160S-MF)和不育植株(MaleSterile/160S-MS)花药细胞学特征进行显微观察;TUNEL染色法检测花药发育各时期绒毡层细胞凋亡情况。160S-MF在15℃表现为可育,雄蕊正常发育,成熟的花药呈黄色,形态饱满,正常开裂,表面一层有活性的花粉附着在上面;28℃条件下, 160S-MS花朵的雌蕊、萼片与160S-MF花朵无差异,但花瓣变小,花丝变短,雄蕊明显退化,花药干瘪呈黄褐色,无花粉粒附着在花药上,表现出雄性完全不育。160S-MF的小孢子能正常发育为成熟有活力的花粉。而160S-MS由于雄蕊完全败育,未观察到小孢子和花粉粒。160S-MS花药在造孢时期和花粉母细胞时期与160S-MF无明显差异,但在减数分裂期,160S-MS花药绒毡层形态和结构出现异常,绒毡层细胞排列不整齐,细胞空泡化,伴随提前解体。同时花粉母细胞发育受阻,无四分体结构形成,最终在减数分裂期完成前形成空的花粉囊。TUNEL检测发现, 160S-MS花药绒毡层细胞在减数分裂期开始凋亡。本研究结果表明, 160S属花粉母细胞败育型不育系,败育时期发生在减数分裂期,绒毡层异常降解,绒毡层未向腺质型转化,不能提供花粉母细胞发育所需要的营养物质,致使花粉母细胞发育受阻无法形成四分体结构,从而导致小孢子无法形成,花药形成空的花粉囊,产生雄性不育。     

Cytological observation of anther structure and genetic investigation of a new type of cytoplasmic male sterile 0A193‐CMS in Brassica rapa L.

Cytoplasmic male sterility (CMS), a maternally transmitted failure in pollen formation, is an effective pollination control system in hybrid rapeseed (Brassica napus) breeding. However, CMS is not widely used in the related oilseed species Brassica rapa. In the past years, several male sterile plants have been isolated from the B. rapa landrace ‘0A193’, collected in Shaanxi, China, in 2011. It is noteworthy that the fertility expression of 0A193‐CMS was affected by temperature. In contrast to pol CMS, fertility tests with 18 B. rapa and 9 B. napus accessions suggest that a different system of maintaining and restoring is responsible for the observed phenotype. Further on, genetic investigation evidenced that fertility of 0A193‐CMS is controlled by both cytoplasmic and one pair of nuclear recessive genes. Interestingly, plants of the 0A193‐CMS type possess a highly specific fragment of the mitochondrial gene orf222, a crucial regulator of male sterility in nap CMS. Our study broadens the CMS resources in B. rapa and provides a highly applicable alternative to pol CMS and ogu CMS for hybrid breeding production.     

甘蓝型油菜白花突变体的遗传研究和白花胞质雄性不育系的选育

用白花突变体和白花不育突变体分别选育白花品系G95150和白花胞质不育系7600 A。遗传研究表明,白花对黄花由一对不完全显性基因控制。7600A在农艺性状上与其保持系G95150完全一致：叶色浓绿,植株较矮（163.5 cm）、生育期较长（243天）、抗寒能力较差（冻害率100%,冻害指数33.8）。7600A花色纯白、花瓣皱缩、花药小、低温存在微量花粉。G95150和7600 A的芥酸含量为0.8854 %,硫甙含量70.5461μmol/g。     

厚轴茶雄性不育株花药败育的生物学特性和细胞学研究

为明确厚轴茶(Camellia crassocolumnaH. T. Chang)雄性不育株花器发育形态、花药和花粉败育时期及兵细胞学特征,利用体视显微镜、石蜡切片技术、染色体制片和DAPI染色法,对厚轴茶雄性不育株和可育株开花迚程、花器形态、花药发育过程、花粉母细胞减数分裂及小孢子发育过程比较观察。结果显示,厚轴茶花属于完全花,花药其四室、呈蝶形,花药壁发育为基本型,绒毡层细胞其双核,于四分体时期形成分泌型细胞,单核花粉期开始降解,花粉母细胞经过减数分裂Ⅰ、减数分裂Ⅱ和胞质分裂后形成四面体型四分体,小孢子呈三角形,成熟花粉为二细胞型花粉。花蕾发育早期,不育株雄蕊发育正常,与可育株无明显差异。花蕾发育后期,不育株花丝弯曲,花药粘连、干瘪、褐化、坏死,不裂药。不育株减数分裂期绒毡层细胞异常增生、排列混乱,单核至双核花粉期绒毡层延迟降解。不育株花粉母细胞减数分裂过程中存在环状单价体、滞后染色体、染色体桥、染色体缺失、不均等分离、微核和多分体等异常现象。不育株小孢子胞质紊乱,单核期花粉粒相互粘附,花粉壁皱缩变形,花粉细胞质和细胞核模糊不清,成熟花粉细胞空瘪凹陷。研究结果表明,厚轴茶雄性不育花...     

Directional transfer of a multiple-allele male sterile line in Brassica campestris L. ssp. chinensis (L.) Makino var. rosularis Tsen et Lee

To produce hybrid seeds of Wutacai (Brassica campestris L. ssp. chinensis (L.) Makino var. rosularis Tsen et Lee), a “directional transfer program” was designed to breed the multiple-allele male sterile line of Wutacai. A multiple-allele male sterile line of Naibaicai (Brassica campestris L. ssp. chinensis L., S01) was used as the male sterile resource, and an inbred line of Wutacai (WT01) was used as the target line. Recurrent backcrossing was employed to transfer the male sterility and other botanical traits simultaneously, while the genotype was identified through test crossing. The male sterility was successfully transferred from S01 to WT01. A new male sterile line, GMS-3, with similar botanical traits to WT01, was bred. Four hybrid combinations were generated with GMS-3 as the female parent. One hybrid (C1) that contained the most desirable traits was developed from the new male sterile line.     

Variations in chlorosis and potential usefulness of alloplasmic Brassica rapa with the cytoplasm of male sterile Brassica juncea

To select superior seed parents for vegetable hybrid seed production, we conducted interspecific crosses between male sterile Brassica juncea (2n = 36, AABB) and eight inbred lines of Brassica rapa (2n = 20, AA). Alloplasmic lines of B. rapa with the cytoplasm of B. juncea were developed from B. juncea × B. rapa hybrids by repeated backcrossing using B. rapa as the recurrent male parent until the BC₃ generation. Seed fertility, male sterility and chlorophyll content were investigated in these plants cultivated under four different temperature conditions (5, 10, 12 and 20°C). At 10°C, the alloplasmic lines of B. rapa with the cytoplasm of B. juncea were male sterile with partly chlorotic leaves. The alloplasmic B. rapa had lower chlorophyll a, chlorophyll b and carotenoid contents than those of the original B. rapa. The leaves recovered from chlorosis when the plants were cultivated at 20°C. An alloplasmic line of B. rapa (A6) is available as a seed parent for vegetable hybrid seed production and contributes seed fertility, slight chlorosis and stable male sterility.     

水稻‘陆18S’核不育基因连锁的分子标记

为了研究水稻不育基因的遗传机理和连锁情况,利用‘陆18S’与3个父本杂交,并对F2进行花粉育性和结实率观察和遗传分析,同时对F2后代进行RAPD分子标记。通过遗传分析得知,‘陆18S’不育系由1对隐性核基因控制。通过分子标记的筛选,找到了与‘陆18S’雄性不育紧密连锁的RAPD标记S490,片段大小为850 bp。获得与不育基因紧密连锁的RAPD标记。为不育基因克隆、定位奠定了坚实的基础。     

Molecular and biological studies on male sterile cytoplasm in Cruciferae. II. The origin of Ogura male sterile cytoplasm inferred from the segregation pattern of male sterility in the F1 progeny of wild and cultivated radishes (Raphanus sativus L.)

Summary To determine the origin of Ogura male sterile cytoplasm in radish (Raphanus sativus L.), wild and cultivated radishes were crossed. Three types of progeny resulted from the F₁ hybrids between the wild radish from Kushikino with Ogura-type mtDNA and the cultivars (Uchiki-Gensuke or Comet). The segregation patterns of the male sterility were compared with those of Ogura cytoplasm. The male sterility induced in the F₁ hybrid was maintained by crossing with Uchiki-Gensuke, that maintains Ogura male sterility. In the two types of progeny, in which Comet (a restorer of Ogura cytoplasm) was used as one of the parents, both fertile and sterile plants segregated at the predicted ratio on the assumption that a single dominant fertility restoring gene exists in the restorer. From these results, we concluded that the Ogura cytoplasm is identical to that of the wild radish, and the former originated in a population of Japanese wild radish.