Development and Application of SCAR Markers for Discriminating Cytoplasmic Male Sterile Lines from Their Cognate Maintainer Lines in Indica Rice

The DNAfragments about 1 600 bp were amplified using random amplified polymorphism DNA （RAPD） primer OPAl2 with the templates of mitochondrial DNA of Zhenshan 97A and Zhenshan 97B, and were sequenced. The nucleotide sequences and lengths of the fragments from Zhenshan 97A and Zhenshan 97B showed no difference. The precise length of the fragment was 1 588 bp. Sequence characterized amplification region （SCAR） primers were then developed to discriminate the cytoplasmic male sterile （CMS） lines and their maintainer lines. A specific 1 588 bp fragment could be amplified with SCAR primers, CHI19F2/CHI19R2 and CHI20F3/CHI23R3, in the mitochondrial DNA of Zhenshan 97A, but not Zhenshan 97B. Furthermore, the specific fragment could be also amplified from the total DNA from green leaf tissues of Zhenshan 97A with SCAR primers, but not Zhenshan 97B. With the corresponding primers, the specific fragment could also be amplified from the total DNA of green leaves of other two CMS lines with wild abortive type cytoplasm （CMS-WA）, namely Zhenpin A and Tianfeng A, but not in their maintainer lines. Moreover, using total DNA as template, each of the four pairs of SCAR primers could also be used to amplify the 1 588 bp fragment in CMS-ID （Indonesia paddy type） line 11-32A but not in 11-32B, and the specific fragment was amplified from the DNA of both F1 and F2 seedlings of Shanyou 63. The results of detecting the genetic purity of a man-made mixture of the seeds of Zhenshan 97A using CHI20F3/CHI23R3 were completely consistent with the phenotypes. Taken together, these results indicated that the specific 1 588 bp-fragment amplified by CHI20F3/CHI23R3 was the unique amplification products of CMS mitochondrial DNA, and could be used to distinguish CMS-WA and CMS-ID lines from their corresponding maintainer lines at the seedling stage.

Influence of Genetic Drift of Restoring Gene (Rf) on Seed Purity of Yuetai A, a Honglian-Type Cytoplasmic Male Sterile Line in Hybrid Rice

The seed samples of Yuetai A, a Honglian （HL） type cytoplasmic male sterile （CMS） line in hybrid rice were investigated to assess the seed purity and to analyze the cause of off-type plants by imitating the biological contaminant to Yuetai A in Nanjing, Jiangsu Province and Lingshui, Hainan Province during 2004-2006. The seed impurity of Yuetai A mainly resulted from the genetic drift of restoring fertility gene （Rt） after biological contamination but not from its sterility unstability. All of the ten maintainer lines, five restorer lines and three thermo-sensitive genic male sterile lines used in the study could pollinate Yuetai A and Yuetai B to produce F1 plants, directly or indirectly resulting in Rf-gene drifting into Yuetai A and generating ＇iso-cytoplasm restoring-generations＇. Furthermore, high outcrossing rate and similar heading date of Yuetai A with many varieties used in rice production might easily result in the biological contamination. After removing all plants with Rf-gene mixed in Yuetai A and preventing Rf-gene drifting into Yuetai A, the seed purity of Yuetai A and Yuetai B had been raised to 100%.

Genetic Mechanism of Dominant Earliness in Kefeng A,a New Rice Cytoplasmic Male Sterile Line

Kefeng A is an early maturing indica cytoplasmic male sterile （CMS） line of rice. Combinations derived from Kefeng A and late maturing indica restorer lines showed dominant earliness to various extents. To understand the genetic basis of dominant earliness, the genotype of photoperiod-sensitive genes in Kefeng A was analyzed using a complete set of heading time near isogenic lines （NILs） EGO to EG7, ER, LR, T65, T65E^b, T65E^bm, T65m, NIL（Hd1） and NIL（Hd4）. Results indicated that Kefeng A contained two dominant photoperiod-sensitive alleles E1 and Se-1^U on E1 and Se-1 loci, respectively, and the genotype of photoperiod-sensitivity genes for heading time in Kefeng A was E1E1e2e2E3E3Se-1^USe-1UEf-1Ef-1. Based on the detected heading time genotype, in combination with the heading time of Kefeng A and the early maturing phenomenon in its derived F1 hybrids, it is speculated that Kefeng A might carry a dominant inhibitor gene Su-E7 for the dominant photoperiod- sensitive gene E1, and a recessive inhibitor gene i-Se-1 for another dominant photoperiod-sensitive gene Se-1. The reason why F1 hybrids from Kefeng A exhibited early maturing was hereby analyzed and the breeding value of dominant earliness related genes in Kefeng A was discussed.

Development of Maweizhan cytoplasmic male-sterile line in rice(Oryza sativa L.)

A male sterile mutant plant was found from the rice field of the local rice variety which was cultivated for a long time in the west of Hubei Province. The plant has more vigorous tillering ability. Its plant height of 95 cm was a bit shorter than that of the normal ones. The plant type, the leaf shape and the color of leaf sheath and glume tip of this mutant were identieal to that of the normal plant whereas the color of arrowhead-shape anther was milky white. This mutant set no seed during self-pollination. When it was crossed with IR24. IR26, Minhui 63 or Xieqing-zaoxuian. the Ffertilities were normal. The fertility of this mutant could be restored by IR24, IR26 and Minhui 63 and maintained by Xieqing-zaoxian. Maxie A was developed in 1987 by the successive backcrossing of the mutant with Xieqing-zaoxian. The percentage of abortive pollen in Maxie A in uninucleate microspore to early binucleate microspore stage is

Experimental and genomic evidence for the indica-type cytoplasmic effect in Oryza sativa L.ssp.japonica

Cytoplasmic effects are important agronomical phenomena that have generated widespread interest in both theory and application. In the present study, five high yield rice cultivars（Oryza sativa L. ssp. japonica） in large-scale cultivation in northeast China were determined to possess Oryza sativa L. ssp. indica-type cytoplasm using cytoplasmic subspecies-specific molecular markers. This was confirmed by cytoplasmic genome-wide single nucleotide polymorphisms（SNPs） and functional gene sequencing. Two of these five japonica cultivars were core breeding parents with high yield and the other three were super-high-yield varieties registered by the Ministry of Agriculture of China. We constructed nuclear substitution lines to further demonstrate whether and how this indica-type cytoplasm contributed to yield improvement by comparing yield components. The results showed that under the same japonica nuclear background, the lines with indica-type cytoplasm had a significant decrease in tillers in exchange for increased grain number per panicle compared with their recurrent parents. Our results implied that botanical basis of this cytoplasmic effect was to reduce the plant＇s branching differentiation to produce more floral organs under the constant nutrition. Our findings open another door for the utilization of inter-subspecific hybridization for the improvement of rice cultivar.

Maxie A- a novel cytoplasm male sterile line

The pollen abortion of Maxie A and Zhengshan97 A belong to stainless type with Ksolu-tion.The maiority of Maxie A abortive Pollenstook cireular shape and few was staining abortion

Differences in Nuclear DNA Between Male-Sterile and Male-Fertile Lines of Sorghum bicolor

Cytoplasmic male sterility(cms)is determined by nuclear-cytoplasmic interactions. Up to now, most studies are focused on the comparison of cytoplasmic DNAs of male-sterile lines and male-fertile lines, and analysis of nuclear DNA has not been documented yet. In order to find out the possible difference in nuclear genome of male-sterile line A1 Tx623 and corresponding male-fertile line Tx623 of sorghum, random amplified polymorphic DNA(RAPD)approach was used to analyze their cytoplasmic and nuclear genomes. Total DNAs of them were amplified at first to screen primers, which were able to generate reproducible bands specific to male-sterile line or male-fertile line. Then the selected primers were used to amplify their mitochon-drial DNA(mtDNA)and chloroplast DNA(cpDNA). The origins of all the polymorphic fragments were analyzed. After ruling out those amplified from cytoplasmic DNA, seventeen polymorphic fragments were determined to be amplified from nuclear DNA. These fragments originated from nuclear DNA indicate that differences in sequence exist between the nuclear DNA of male-sterile line and male-fertile line of sorghum, which do not agree with the traditional standpoint that they have identical nucleus.

Lodging Resistance of Aromatic CMS Line Zhongzhe A and Its Derived Lines

Nineteen rice combinations derived from Zhongzhe A and its derived lines, as well as Y Liangyou 1 as the control, were used to study lodging resistance by detecting plant height and some of the traits of culm and panicle that are related to lodging. The results indicated that the lodging resistance of 16 combinations was significantly stronger than that of Y Liangyou 1. Moreover, the lodging resistances of all combinations derived from Zhongzhe 2A, Zhongzhe 3A, Huazhe A and Zhong 1A were significantly higher than that of Y Liangyou 1. Additionally, the traits related to lodging were not identical within different CMS rice lines, and the relationship between plant height and lodging resistance was only significantly (P < 0.01) detected in Zhongzhe 2A. Some traits of the second internode were closely related to lodging in all combinations, which can be used as an effective index in lodging resistance breeding in rice.

A Study on Comparative Fertility Restoration in A2 and A4 Cytoplasms and Its Implication in Breeding Hybrid Pigeonpea [Cajanus cajan (L.) Millspaugh]

Exploitation of hybrid vigour has been visualized as the most efficient option for increasing productivity in pigeonpea [Cajanus cajan (L.) Millspaugh]. Cytoplasms from various wild relatives of pigeonpea have been transferred to develop CMS lines in the background of cultivated pigeonpea. However, A2 (Cajanus scarabaeoides) and A4 (Cajanus cajanifolius) cytoplasms have been utilized most frequently. In order to study fertility restoration efficiency in F1 hybrids having either A2 or A4 cytoplasms, an experiment was conducted at the Indian Institute of Pulses Research (IIPR), Kanpur during 2008-2012. Four CMS lines namely Hy4A, H28A (each with A2 cytoplasm), ICP 2039A and ICP 2043A (both with A4 cytoplasm) were crossed with ten genotypes/restorers of long duration pigeonpea for two years. The F1 hybrids so-obtained were assessed in the succeeding years for pollen fertility and pod setting. All the pollinators except IPA 203 restored fertility in F1 hybrids derived from ICP 2039A and ICP 2043A (both having A4 cytoplasm). However, none of the restorers were effective in restoring fertility in hybrids derived from Hy4A and H28A (each with A2 cytoplasm). This could be ascribed to undesirable linkage drag still present in these two CMS lines having A2 cytoplasm. The F2 progenies derived from 4 hybrids (ICP 2039A × NA-1, ICP 2039A × Bahar, ICP 2043A × NA-1 and ICP 2043A × Bahar) segregated approximately into 3 fertile: 1 sterile plants. However, 2 F2 progenies having Pusa 9 as the restorer revealed approximately 15 fertile:1 sterile ratio. Thus monogenic and digenic duplicate gene action with complete dominance for fertility restoration was observed in F1 hybrids derived from CMS lines having A4 cytoplasm. F3 progenies from individual F2 plants of these crosses also confirmed the same pattern of fertility restoration. This study indicated that CMS lines based on A4 cytoplasm would be more desirable as these might have more number of restorers compared to those having A2 cytoplasm.

结球甘蓝系列杂交种(GL22)的选育

【目的】利用自有结球甘蓝种质资源,根据市场对口感型、鲜食型品种的需求,选育出更多性状优良、符合市场供需的结球甘蓝品种。【方法】以团队前期选育的13个结球甘蓝Ougra不育材料为母本,10个结球甘蓝自交系材料(GL14000-14009)为父本,通过杂交,配制14个结球甘蓝杂交组合材料,分别从开展度、外叶数、纵径、横径、中心柱长度、品质测定、品质鉴定、产量和抗病性等方面进行比较筛选。【结果】筛选出的4个结球甘蓝杂交组合材料GL22-02、GL22-06、GL22-11和GL22-13,在农艺性状、优质性和产量均优于对照种特加2号,叶球均呈圆球型,帮叶比分别为26.9%、20.8%、23.1%和16.8%,均优于对照种(31.3%);叶球紧实度分别为0.76、0.73、0.59和0.62 g/cm^(3),比对照种高0.16 g/cm^(3)以上;中心柱长度均小于叶球高的1/2,分别为4.9、4.3、4.8和4.6 cm;水分含量分别为93.22%、94.17%、93.75%和93.61%;蛋白质含量分别为1.51%、1.28%、1.39%和1.36%;可溶性糖含量分别为5.61%、5.69%、5.56%和5.84%,比对照种高0.14~0.37个百分点;粗纤维含量分别为0.61%、0.71%、0.69%和0.67%,比对照种低0.08~0.18个百分点;维生素C含量分别为682.3、687.1、699.1和682.3 mg/kg,比对照种高48.4~65.2 mg/kg;经食用品质鉴定,筛选出的结球甘蓝4个杂交组合材料,叶球生(鲜)食,质地脆嫩,口感较甜。结球甘蓝组合材料的黑腐病抗病能力均为高抗(HR),且与对照种相同;产量分别比对照种增产4.80%、8.46%、10.97%和8.46%。【结论】筛选出的GL22-02、GL22-06、GL22-11和GL22-134个组合材料,综合农艺性状和经济性状优良,可进一步大面积推广示范。

朝天椒新品种‘石辣6号’的选育

‘石辣6号’是以辣椒核质互作型雄性不育系T108A为母本,恢复系Q1-352C231为父本杂交配制而成的朝天椒一代杂交种。中熟,平均始花节位14.5节,播种到红熟131 d。单株挂果210个左右,单果质量4.6 g左右。果实小羊角形,果面微皱,果纵径9 cm,果横径1.3 cm,果肉厚1.4 mm,平均制干率27.81%。辣椒素总含量1.33 g/kg,辣度2.05万SHU。在西南地区一般每667 m^(2)产鲜红椒1 500 kg左右,田间表现高抗疫病、抗病毒病、高抗细菌性叶斑病。该品种为鲜食加工兼用型品种,加工品质好,适宜在西南地区海拔高度500~1 500 m及相似区域作春夏露地及早春地膜覆盖种植。

水稻同核异质广亲和不育系细胞质效应的研究

利用同核异质广亲和不育系真系秋光 A,研究 3种不育细胞质对杂交稻 16个性状的遗传效应。结果表明 :(1)不育细胞质在结实率、每穗实粒、单株产量、株高 4个性状上表现显著的负效应 ,在抽穗期、千粒重 2个性状上表现显著的正效应 ,单株穗数、每穗总粒及 8个品质性状不育细胞质效应不显著 ,不育细胞质效应与相对效应的分析结果基本一致 ;(2 )不育细胞质遗传效应的大小与细胞质的可恢复性有关 ,BT型细胞质的可恢复性较好 ,细胞质效应较小 ,WA型细胞质最难恢复 ,细胞质效应最大 ;(3)品种间组合和亚种间组合的不育细胞质效应无显著差异 ,但杂种不育细胞质效应的大小与恢复系恢复力的强弱有关 ;(4 )某性状不育细胞质效应的大小和有无决定于该性状与育性性状的密切程度。

高粱雄性不育系、保持系正负极向过氧化物酶同工酶的电泳比较

对高粱雄性不育系、保持系不同生长发育阶段叶片中的正、负极向过氧化物酶同工酶进行了检测。结果表明,叶片中正极向过氧化物酶同工酶谱两者基本相同,说明正极向过氧化物酶在不同生长发育时期是稳定的。负极区域中,在叶片发育过程中有2条酶带消失,证明在这个区域中遗传信息出现顺序表达现象。花粉粒发育过程中,不育系的正极向过氧化物酶带始终多于保持系。作者认为,不育细胞质基因可影响编码过氧化物酶的核基因的表达,引起雄性不育。不育细胞质基因可能也同时具有调节基因的功能,表现为具有解除阻遏的作用,使不育系花粉粒发育过程中部分过氧化物酶基因得以表达;而保持系不具有这种解除阻遏的细胞质不育基因,使部分基因仍处于阻遏状态,造成保持系中过氧化物酶同工酶谱带少于不育系的现象。不育细胞质基因的这种调控作用,同样有可能影响核基因遗传功能的正常发挥,引起核质之间的不协调而导致雄性不育。

不同小麦雄性不育类型光合、生理参数日变化的研究

利用2套同核异质的K、T、V、CHA型不育系及其保持系，对其不同生育时期净光合速率（Pn）、气孔导度（Ga）、蒸腾速率（r）、水分利用率（WUE）、光量子通量密度（PFD）和细胞间隙CO2浓度（Ci）、气孔限制值（Ls）等光合、生理参数的日变化及其差异进行比较研究，探讨不同小麦雄性不育类型的胞质效应。结果表明，供试材料净光合速率的日变化均呈双峰曲线，有明显的光合“午休”现象，Pn与Gs、Ci的相关系数分别为0．8187、0．8136，呈显著正相关（r0.05=0．8110），与Ls的相关系数为-0．8496，呈显著负相关（r0.05=0．8110），Pn的午间下降伴随着Gs、Ci，的下降和Ls的升高，表明其主要受气孔因素限制；与保持系的Pn值相比，CHA型和K、T、V型不育系分别降低0．88、2．76、3．30和2．04pmolCO2m^-2s^-1，产生不同程度的负效应，尤以T型和K型最明显。在水分利用率上，K、T、V型不育系较保持系降低0．94—1．54μmol CO2mmol～H2O，负效应显著；CHA型不育系较保持系低0．36μmolCO2mmol^-1H2O,差异不显著，说明CHA对旗叶水分利用率无明显的不良影响。Pn值因母本基因型的不同而异，冀5418及相应不育系的Pn值较太911289的高，差异达显著或极显著水平。因此，选择优势效应大的保持系回交，有利于降低不育胞质对小麦光合功能的负效应。

红莲型细胞质雄性不育恢复品种的筛选与分类

以红莲型细胞质雄性不育系粤泰 A为母本与不同品种杂交 ,调查了 5 2个组合 F1 的花粉育性和小穗育性。结果表明 :这些品种对红莲型细胞质不育的恢复类型较为复杂 ,在所研究的品种中 ,只有 5 .77%的品种对红莲型细胞质不育系具有保持能力 ,其余则对红莲型细胞质不育系具有一定的恢复能力 ,这些对红莲型细胞质不育系具有恢复能力品种在恢复力上也存在一定的差异 ;就对红莲型细胞质不育系具有恢复能力品种的分布而言 ,这些品种的分布范围较广 。

Ogura细胞质甘蓝雄性不育系选育及其利用

利用Ogura不育源，对上海地区不同类型的甘蓝材料进行转育，获得了两个Ogura细胞质甘蓝雄性不育系94BC－15，94BC－12。这两个不育系的不育性稳定，克服了不育源存在的蜜腺退化及雌蕊畸形造成结实不良的生理缺陷，并基本克服了苗期低温黄化现象，具有利用价值。利用不育系94BC－15与亲本92－B6杂交育成了杂种一代“沪甘一号”，该杂种一代具有生长势强、耐热性好、抗霜霉病和TuMV、综合园艺性状优良等特点，产量比“夏光甘蓝”增产10％左右。

D^2型山羊草细胞质对普通小麦性状影响的研究

以含有粗厚山羊草 (6 X)、牡山羊草、瓦维洛夫山羊草等 D2 型异源细胞质的 3个稳定普通小麦(Triticum aestivum)异质系为材料 ,分别与 6个普通小麦品系杂交 ,调查该细胞质对供试小麦育性、生长势和主要农艺性状的影响。结果表明 :D2 型细胞质对普通小麦的育性反应差异性显著 ,相对而言牡山羊草细胞质对杂交小麦的生产利用价值更大 ,对普通小麦农艺性状无不良的细胞质效应 ,能改良小麦品质和提高小麦对白粉病的抗性。

辣椒细胞质雄性不育系和保持系过氧化物酶同工酶的比较分析

运用辣椒细胞质雄性不育系21A和保持系21B为试材,比较分析了过氧化物酶(POD)同工酶在幼叶和不同发育时期花蕾中的表达特征.结果表明,辣椒花蕾中的POD同工酶谱带均比叶片中的更丰富,表现出明显的组织特异性.不育系21A和保持系21B间的酶谱在幼叶和小花蕾(纵径0.8 ～1.5 mm)中基本无差异,但从中花蕾(纵径2～3 mm)开始,保持系21B的一些酶带(POD4b和POD4c)染色开始减弱.在大花蕾(纵径4.5～5 mm)和特大花蕾(纵径6.8～7 mm)时期,不育系比保持系分别多2条酶带(POD2c和POD4b)和1条酶带(POD2c),表明辣椒细胞质雄性不育系21A与保持系21B花蕾中的POD同工酶表达与小孢子的发育过程相关,其表达差异发生在细胞学上观察到的败育之前.

花椰菜雄性不育系的选育与应用

以3份欧洲花椰菜细胞质雄性不育材料为不育源,用花椰菜小孢子培养的纯系和高代自交系为轮回亲本进行转育,连续回交4代,育成一批综合性状优良、配合力强、雄性不育株率和不育度均达100%的花椰菜胞质雄性不育系及相应的保持系。稳定的不育系用组培快繁技术繁育,并利用该不育系配制一代杂种,经田间鉴定筛选出3个不同类型的优良杂交组合。