不同温敏型两系杂交稻F1育性温光效应的研究

采用盆栽方式,通过人为疏枝减库平衡库源关系,研究短日低温、高温,长日低温、高温条件下不同温敏型两系杂交稻F1育性(受精率)的变化。结果表明：1,低温敏型F1育性稳定,不论长日或短日都对温度变化表现钝感。高温敏型及反向温敏型F1育性对温度的反应与其母本基本一致;2,温度高低不是影响不同温敏型F1育性变化的唯一因子     

实用籼型水稻温敏核不育系种质创制进展及未来主攻方向

不育系是杂交水稻的“芯片”,不论三系法还是两系法,品种的不断突破都取决于不育系种质的发现与持续创新。自水稻光敏核不育种质农垦58S被发现以来,水稻两系法杂种优势利用研究已历经50年,目前两系法杂交水稻已占据我国杂交水稻半壁江山。作者通过总结我国水稻光温敏两用核不育系选育历程、取得的主要成就,以及作者团队在制种安全实用籼型水稻温敏两用核不育系创制方面取得的一系列进展,提出未来实用型水稻两用核不育系育种的主攻方向。     

水稻籼型温敏核不育系之5038S的选育与应用

之5038S是以广占63S为母本、矮3S为父本杂交选育而成的水稻籼型温敏核不育系,具有不育性稳定、开花习性好、配合力较强、异交结实率高等特点。于2020年5月通过浙江省农作物品种审定委员会审定。本文介绍了其选育过程、特征特性及繁殖技术要点。     

水稻长穗颈隐性高秆突变体穗颈节间的细胞学观察

【目的】揭示长穗颈温敏核不育水稻双低培eS穗颈节间伸长的细胞学机制。【方法】以双低培eS为研究对象,以双低S为对照,于育性转换敏感期,在25℃人工气候条件下处理6 d,比较研究了双低培eS和双低S不同发育时期的穗颈伸出度、穗颈节间长度及节间细胞数和细胞的平均长度。【结果】长穗颈双低培eS与双低S穗颈节间薄壁细胞数及细胞平均长度在减数分裂期和二核花粉期差异不明显,于三核花粉期差异达显著水平,始花当天和始花后第7天均达极显著水平,其中始花后第7天时两者的差异最大。在始花后第7天,双低培eS穗颈节间较双低S长18.1 cm,其纵列外层薄壁细胞和内层薄壁细胞数分别较双低S多1 277和605个;外层薄细胞和内层薄壁细胞平均长度分别较双低S长22.9和37.9μm,尤其是节间中部区段的外层薄细胞和内层薄壁细胞分别较双低S长25.0和49.0μm。【结论】长穗颈隐性高秆突变体双低培eS的穗颈节间伸长是由幼穗分化后期细胞数增多和细胞长度增加双重作用引起的,其中以后者的作用更显著。     

Relationship Between Phytohormones and Male Sterility in Thermo-Photo-Sensitive Genic Male Sterile (TGMS) Wheat

Summary Fertility alternation normally occurs in a novel type of thermo-photo-sensitive genic male sterile (TGMS) wheat whose recessive genes in the nucleus are expressed as virtually complete sterility under lower temperature and shorter daylight conditions, but as normal fertility under higher temperature and longer daylight conditions during the developmental period from meiosis of pollen mother cells (PMCs) to the early mononucleate stage of microsporogenesis. In order to provide more information about the mechanism(s) of fertility alternation in TGMS wheat, the relationship between fertility alternation and levels of phytohormones was analyzed by endogenous hormone quantification and exogenous hormone treatments in the present research. Sown at an earlier date with a relatively low temperature and short daylight, TGMS wheat was male sterile phenotypically. Pollen abortion mainly occurred at the mononucleate to bi-nucleate stages of microsporogenesis and pollen abortion was mainly of the spherical type. Levels of endogenous indole-3-acetic acid (IAA), abscisic acid (ABA) and gibberellic acid (GA₃) in the anthers were at lower levels, and zeatin riboside (ZR) was higher. Sown at a later date, when the temperature during the critical period for fertility alternation was relatively high and the daylight was long, TGMS wheat was almost as fertile as the normal genotype and the contents of endogenous IAA, ABA and GA₃ in anthers were at higher levels, and the content of ZR was at a lower level. At the critical period for fertility alternation, treatments with exogenous IAA, ABA, GA₃ or aminoethoxy vinylglycine (AVG), an inhibitor of ethylene biosynthesis, decreased the frequency of sterile pollen grains and increased the frequency of self-pollinated fertile florets. Treatment with exogenous 2-chloroethyl phosphonic acid (CEPA), a releaser of ethylene, increased the frequency of sterile pollen grains and decreased the frequency of self-pollinated fertile florets. It was thus suggested that the fertility alternation of TGMS wheat was closely related to levels of phytohormones in the anthers, and changes of endogenous hormone levels were among the important factors responsible for the fertility alternation of TGMS wheat.     

温光敏核不育小麦C412S的育性转换及其APRT基因的表达

以选育的小麦(Triticum aestivum L.)温光敏核不育系C412S为试材,以C412S回交转育时的受体亲本C412为常规品系对照,通过分期播种试验研究了其育性转换特性。用涂抹压片法观察减数分裂和小孢子发育进程,用半定量RT-PCR技术分析不育与可育条件下不同发育时期的幼穗中腺嘌呤磷酸核糖基转移酶基因(APRT)的表达水平。结果表明,通过调整播种期改变雄性发育的温光条件,C412S表现出完全不育—高不育—半不育—正常可育的育性转换特性。C412S花粉败育的高峰在单核小孢子晚期,主要表现圆败型不育。C412S的育性敏感期是从花粉母细胞形成期到成熟花粉期,其中最敏感的时段是花粉母细胞形成期到减数分裂期。与对照相比,C412S的APRT1基因序列有个别碱基变异,但编码氨基酸序列没有变化。在花粉母细胞形成期至单核期,与晚播可育条件相比,早播不育的C412S幼穗中APRT基因转录水平下调,因此认为,其育性转换与幼穗中APRT基因转录水平有一定关系。     

温度对隐性长穗颈温敏不育水稻eui基因表达的影响

 为了解杂交稻不育系抽穗不畅问题，以隐性长穗颈温敏核不育水稻长选3S为材料，采用田间调查和人工温度处理方法研究了温度对隐性长穗颈基因（eui）表达的影响。结果表明，长选3S穗颈伸出剑叶叶鞘的长度与始花前9～20 d自然条件下的日均温度呈负相关，其中以始花前12～17 d(花粉母细胞形成至减数分裂期)日均温度负相关性最显著。在eui基因表达对温度最敏感的时期进行4种人工温度处理，22℃、24℃、26℃和28℃。28℃条件下eui基因表达受阻；22～26℃条件下eui基因表达，且穗颈伸出剑叶叶鞘的长度随温度降低而增长。     

Studies on Breeding and Application of Thermo- sensitive Genic Male Sterile Line 402S in Brassica napus：Ⅱ. Evaluation of Heterosis and Combining Ability

Augmented randomized complete block test was conducted to evaluate the heterosis of 80 hybrid combinations from TGMS line 402S and its original parent Xiangyou 91S, and the combining ability of 40 testcrossing lines. The results of identification test showed that among 47 combinations yielding over the control Xiangyou 15, 17 ones with 402S and 3 ones with Xiangyou 91S overyidded more than 20%, reaching the significant level of 1% ; and arrrmg 51 combinations yielding over their corresponding higher yield parents, 18 ones with 402S and 9 ones with Xiangyou 91S overyielded at 5 % or 1% significant level. The test for the GCA effect of all parents indicated that 402S possessed a stronger combining ability than Xiangyou 91S on yield, siliquae of main inflorescence, total siliquae per plant, seed yield of single plant and 1000- seed weight. 10 testcrossing lines with high GCA were picked out for next testcrosses. Amnng 8 agronomic traits, total siliquae per plant and seed yield of single plant were regarded as the key selecting indexes accccding to the correlation analysis between yield and the agronomic traits on heterosis and on the GCA effect of all parents.     

两系杂交水稻不育系南繁精细化气候区划研究（英文）

利用海南18市县气象站1961~2010年1~3月气候资料和地理信息数据,根据两系杂交水稻不育系育性敏感期和抽穗扬花期的温度指标,应用GIS插值技术,采用综合评判的方法制作两系杂交稻不育系南繁精细化气候适宜性区划图,以期为气候变暖背景下两系杂交水稻不育系南繁提供合理规划布局和可持续发展提供科学依据。结果表明:适宜种植区主要分布在五指山、尖峰岭和吊罗山以南区域,次适宜区向北扩展到五指山市中部以及东方、昌江、琼中和万宁的南部,其它大部分市县区域为不适宜区。     

水稻温敏核不育系33 S特性研究

对33S形态特征、育性、异交习性等进行了研究,该不育系属中熟中稻类型,株叶形态好,不育起点温度低,花时早,午前花率高,异交习性好,制种较易获得高产。