甘蓝型油菜矮秆材料LSW2018的创制

本研究以德油5号F₁作母本，自育新品系273R作父本配制杂交组合，在其F₂群体中出现6株苗期株型明显矮缩的变异株，经5代纯化后育成稳定的甘蓝型矮秆油菜新种质“LSW2018”。该种质苗期苗型矮缩、匍匐生长，叶面皱缩，叶片厚，叶柄短，叶色深；现蕾至成熟期，植株逐渐转为正常形态，茎秆粗壮，节间短，抗倒性特强，分枝部位低，其开花习性、分枝角度、花序特征、一二次分枝数等性状与同源正常高秆品系HSW2018无明显区别，而株高和分枝高度差异极显著。LSW2018育苗移栽平均株高为136.24 cm、直播平均株高为110.4 cm，是适宜机械化、轻简化种植的矮秆甘蓝型油菜新种质，具有较高的利用价值和广阔的应用前景。     

甘蓝型油菜品种的细胞质育性类型初探

利用湘矮A(来源于波里马不育胞质)的同核异质可育系(即保持系)湘矮B与引自8个国家的43个甘蓝型油菜品种(Brassica napus L.)测交,根据F_2群体的育性分离情况,鉴定出34个品种具有N细胞质,9个品种具有S细胞质。认为此法可作为油菜品种细胞质育性鉴定的可行方法之一。     

利用人工合成甘蓝型油菜创建油菜新种质

为了拓宽甘蓝型油菜的遗传基础,从四川、重庆、云南和西藏部分地区采(收)集了一批白菜型油菜、白菜和白花芥蓝地方品种,包括一部分白菜型油菜野生种和半野生种,通过远缘杂交,人工合成了一批甘蓝型油菜新材料。这批新材料具有丰富的遗传变异,主要包括特长角、大粒、多分枝、矮秆、黄籽、白花、抗病等重要遗传类型,部分材料具有重要的育种及研究利用价值。     

我国甘蓝型油菜远缘杂交和种质创新研究进展

本文对我国在甘蓝型油菜远缘杂交及种质资源创建方面的研究进行了总结与展望。我国重要的油料作物甘蓝型油菜系20世纪30、40年代由国外引入,取代白菜型与芥菜型油菜后于60、70年代大面积栽培,故遗传基础较狭窄。但我国的白菜和白菜型油菜、芥菜与芥菜型油菜具有非常丰富的变异类型,可为甘蓝型油菜的遗传改良提供许多所需的性状及基因,我国进行了大量的芸薹属种间(甘白、甘芥)杂交,培育出了优异品种与骨干亲本中油821、黄籽新材料、抗菌核病与根肿病新材料。还运用组织培养与体细胞融合技术,合成许多甘蓝型油菜与其他属植物的有性及体细胞属间杂种、附加系与易位系,选育出可供育种利用的新材料、新型的细胞质雄性不育系及恢复系。     

我国甘蓝型油菜品种(系)的系谱初析

我国油菜种植历史悠久,各地生态条件和栽培制度复杂,形成了十分丰富多彩的油菜品种资源。本文仅就五十年代以来,我国所选育的甘蓝型油菜品种(系)就其亲缘关系进行了系谱分析,以供油菜育种工作的参考。 一、我国育成的甘蓝型油菜品种的亲缘 甘蓝型油菜(B.napus)原产欧洲。我国种植的甘蓝型油菜是在三、四十年代分别从日本和英国引入(刘后利:1984,《作物学报》10(1):16页)。1953年甘蓝型油菜品种胜利     

矮秆小粒水稻潇湘矮的形态学与分子遗传学分析

【目的】研究揭示潇湘矮矮秆小粒的遗传机制,为潇湘矮的育种利用提供理论基础。【方法】利用水稻育种过程中自然突变而得到的稳定遗传的矮秆小粒水稻材料潇湘矮,对其进行农艺性状考查、赤霉素(GA_3)和油菜素内酯(BR)敏感性分析、遗传学分析,并利用潇湘矮与其近等基因系NIL(NIP)衍生的F_2群体对控制矮秆小粒的基因xxa进行图位克隆,最终利用转基因互补试验验证候选基因。【结果】潇湘矮除表现为矮秆小粒外,其穗长变短,穗型紧凑,千粒重极显著下降。不同浓度梯度的赤霉素(GA_3)和油菜素内酯(BR)处理,发现潇湘矮对GA_3部分敏感,而对BR不敏感。遗传分析发现其符合孟德尔3∶1分离规律。图位克隆将xxa基因定位于第5染色体In Del标记F81和F82之间约70 kb区间的物理距离内。该区间包含8个开放阅读框(ORF)。其中,第5个ORF(LOC_Os05g26890)被注释为水稻株高基因D1。序列分析发现,潇湘矮的D1基因在第5和12外显子分别有1个碱基的无义替换和3个碱基的缺失,其中第12外显子3个碱基的缺失导致1个赖氨酸的缺失。转基因互补显示D1可以恢复潇湘矮的表型。【结论】潇湘矮控制株高的途径可能与GA_3代谢有关;潇湘矮矮秆小粒表型符合单隐性核基因控制的遗传规律;潇湘矮矮秆小粒性状是由D1基因突变所致。     

芥菜型油菜主要经济性状配合力和遗传力的初步研究

有关作物数量性状的配合力、遗传力的研究,在玉米、水稻、小麦等作物中报道较多。油菜方面印度学者曾对芥菜型和白菜型油菜进行过一些研究。近年来,我国学者对甘蓝型油菜主要经济性状的遗传力、遗传进度等进行了研究。为了探讨国内外芥菜型油菜主要经济性状的遗传规律,为育种工作提供一定的信息,使杂交育种工作能较好地选配亲本和确定杂种选择的世代,作者用六个国外芥菜型品种与五个当地芥菜型品种(系)组成6×5不完全双列杂交,估算了全株角果数等性状的配合力、遗传力等遗传参数,为确定选择方法提供参考。     

不同生态类型甘蓝型油菜在青海生态条件下的杂种优势表现

利用SSR分子标记研究35份不同生态类型甘蓝型油菜品种(系)的遗传多样性,并从中挑选有代表性的6个春性和6个半冬性材料按完全双列杂交方法(Griffing II)组配成66个组合,考查不同生态类型组合的杂种优势,并分析遗传距离与杂种优势的关系。结果表明不同生态类型的35份品种(系)在遗传相似系数0.698处分为5类,第I类主要为春性材料,半冬性材料分布于第II、III、V类,聚类分析结果与材料的生态类型基本一致;春性品种(系)与半冬性品种(系)组配的组合要比同种类型品种(系)间组配的组合具有更强的杂种优势;SSR的分子遗传距离与大多数性状F1表现及杂种优势相关不显著,利用SSR预测杂种优势效果还不明显。     

甘蓝型油菜细胞质雄性不育新材料RM5637A的遗传研究

以不育系RM5637A与Polima CMS和陕2A CMS的保持系，恢复系和核不育两型系以及116份国内外不同来源的甘蓝型油菜品种（系）作杂交试验。结果表明，RM5637A不育系是不同于Polima CMS和陕2A CMS及核不育两型系遗传背景的另一类细胞质雄性不育系统。不育性除受胞质不育基因控制外还受3对独立遗传并具有相同作用的重叠隐性基因控制，恢复源十分广泛，现有甘蓝型油菜中约有73．3％的品种（系）均为其恢复系。     

甘蓝型油菜波里马细胞质雄性不育的研究与利用

为了扩大恢复源,1988-1989年用49个甘蓝型、芥菜型品种与波里马不育系测交,发现三个全恢材料。波里马不育胞质F_1的生育期、菌核病的感染程度和经济性状无不良负效应。选育冬播油菜不育系比选育春播油菜不育系要困难。本文还对油菜的起源进化与三系选育的关系进行了讨论。     

Genetic Analysis of Early Generation Stability in Rice

The mechanism of early generation stability （EGS） in rice was studied via genetic analysis. Three types of crosses were made, namely between EGS varieties, EGS and conventional rice variety, and conventional rice varieties. The genetic analysis was based on the stable lines in F2 population. The stable lines may appear from some combinations of EGS rice crossing with each other and EGS rice crossing with conventional varieties at different frequencies, but stable lines didn＇t appear in conventional varieties crossing with conventional varieties. Genetic analysis results indicated that the EGS phenomena should just exist in special rice materials, and the frequency of stable lines was closely related to the EGS traits of parents. The EGS traits were neither qualitative nor quantitative traits, and they were controlled by neither dominant genes nor recessive genes. The EGS traits might be inherited by F1 single plant, and the traits of F3 and F4 were corresponded to those of F2 population, i.e. F3 and F4 lines derived from non-segregating F2 showed uniform agronomic traits, and those from segregating F2.did not. The agronomic traits of EGS lines were consistent with those of F1 single plant. On the other hand, when EGS lines occurred, the segregating lines in Mendelian manner were also observed in all F2 population of the same combination. It was suggested that the reason why the stable strains occurred might be a special factor to control （open/close） gene at the beginning of cell division in zygote, resulting in closing mitosis and opening somatic reduction. The somatic reduction of zygote resulted in recombination and homozygosity forming in F1 single plant, and some lines with uniform agronomic traits were observed in some lines of F2 population.     

适宜茶园套种的绿肥型油菜资源筛选及初步应用

为推广生态茶园的油菜绿肥套种模式，于2017-2018年在茶园系统筛选和评价适宜套种的油菜资源。比较23个不同油菜品种（品系）的盛花期鲜草的生长与养分还田量，结果发现：茶园套种油菜的生物量、株高、养分还田量等指标表现存在差异；种植后根际土pH、有机质、碱解氮含量发生改变或提升。综合比较分现，品种阳光131、 圣光86和中双11表现相对较好：单株生物量达0.81～1.00 kg；植株养分还田量高，三者的氮磷钾养分还田量分别为 49.21～72.48 kg/hm2、12.64～17.40 kg/hm2和33.64～56.29 kg/hm2，可基本满足茶青的生长需求，且三个品种种植后土壤有效养分和有机质的改善较为明显。大地69和油肥1号株高相对较矮，适宜在低龄或矮枞茶园中套种。于2018-2019年探索油菜品种阳光131作为绿肥在不同树龄的茶园套种的应用，发现土壤的有机质含量显著改善，pH 值显著提升。综上，认为优选油菜品种应用于冬季茶/油菜（绿肥）套种模式     

Clonal performance of perennial Oryza sativa/O. rufipogon selections and their combining ability with O. sativa cultivars for survival, stolon production and yield

In Southeast Asia, upland rice (Oryza sativa) is an annual crop typically grown for subsistence on hilly lands that are at risk for soil erosion. If perennial cultivars of upland rice were developed, they would provide farmers with an inexpensive tool to produce a preferred food while conserving soil. O. rufipogon, the undomesticated progenitor of O. sativa, includes perennial and stoloniferous forms. To evaluate the feasibility of developing perennial cultivars by combining genes of O. sativa and O. rufipogon, four trials were conducted in an upland field at IRRI: O. sativa/O. rufipogon F₁ clone and cutting height trial, F₂ family trial, and two O. sativa/stoloniferous-selection factorial mating design trials. Plants were established at the beginning of the rainy season, then subjected to a 6-month dry season and evaluated for survival after 1 year. Of the 2101 cultivar control plants, only three IR47686-1-4-B individuals survived and none produced stolons. The 18 F₁ clones, which were selected from previous trials with less drought stress, ranged in survival from 4.4 to 91.4%. Cutting height at harvest did not affect survival. Survival among the F₂ families ranged from 9.4 to 31.9%. Segregation for stolon presence did not differ from a 3:1 ratio for five of the six F₂ families, suggesting the effect of a single dominant gene. Average yields per plant for the F₂ families were 1/3 to 1/9 of yields for the cultivars. However, by crossing the F₁s to cultivars, yield potential was almost fully recovered. For the full-sib families of the factorial trials, survival ranged from 0.0 to 48.6%. Azucena and IR47686-1-4-B, both japonica cultivars, exhibited greater general combining ability for survival relative to the six other cultivar parents. Thus, the process of developing perennial cultivars of rice should include screening annual cultivars to identify those with the best combining ability for survival. To develop cultivars of perennial upland rice, drought avoidance and/or tolerance from annual upland cultivars must be combined with the capacity for perennial growth from wild perennial species. The frequency of stolonifereous testcross progeny was lower than expected and was affected by the O. sativa parent. Thus, additional genes likely affected stolon penetrance and expression. Analyses of covariance indicated that stolons improved the likelihood of survival for progenies of the factorial trials but the effect was small (b < 0.1), and that yield (g/plant) had a small negative effect on percent survival (b = −0.13 to −0.32). This study demonstrated that it was possible to introgress genes for perennial growth from wild O. rufipogon accessions into domesticated O. sativa. Additionally, strategies for developing perennial cultivars of upland rice were improved.     

Prediction criteria of promising F3 populations in durum wheat: A comparative study

Effective selection of parental material and promising segregating populations is an essential requirement for breeding success. There are many contradictive reports about the best parent selection criterion for the development of promising crosses. For the clarification of this problem field experiments were conducted for four consecutive years to compare the effectiveness of six criteria for the prediction of the most promising F₃ populations in durum wheat (Triticum durum L.): the mid-parent value, the F₁, the F₂, the (F₁ + F₂)/2, and the genetic distance among the parents as it is calculated using the SSR and RAPD molecular markers. During the first growing season (2003–2004) nine commercial cultivars of durum wheat and four landraces were crossed. The following growing season (2004–2005), 17 crosses (F₁ generation) were evaluated under low plant density (1.15 plants m⁻²) in a replicated (R-21) honeycomb design. During the third growing season (2005–2006), the four highest yielding crosses, one cross with an intermediate yield, and the three crosses with the lowest yield (F₂ generation) were evaluated under low plant density in a R-9 honeycomb design. Finally, in the fourth growing season (2006–2007) progeny of the aforementioned eight crosses (F₃ generation) and the ten parents were evaluated in a randomized complete block design in two locations. Furthermore, the genetic distance among the parents was determined using the SSR and RAPD molecular markers. It was observed that the three F₃ populations with the lowest yielding ability were the ones with the lowest mid-parental value. In addition, one of the two top F₃ populations was second in the rank according to the mid-parental value. Furthermore, the two top F₃ populations were also the highest yielding in the F₁ and F₂ generations. On the contrary, none of these crosses were predicted by the genetic distance as it was calculated using the SSR and RAPD molecular markers. It was concluded that parental pairs with high mid-parental value and high combined yield (F₁ + F₂)/2 obtained after evaluation of their F₁ and F₂ at low plant density was the most effective way to predict promising F₃ populations.     

田间补充灌溉施肥对菠萝生长、产量及水肥生产力的影响

为探明菠萝田间控水减肥效应及确定补充灌溉施肥水平,为粤西地区菠萝生产中节水节肥和提质增效提供依据。研究以金菠萝‘MD-2’为材料,设置无灌溉常规施肥（常规）,2个补灌W₁（-15~-35 kPa）和W₂（-35~-55 kPa）与3个肥料F₁（100%）、F₂（75%）和F₃（50%）梯度处理（F₁W₁、F₂W₁、F₃W₁、F₁W₂、F₂W₂、F₃W₂）,以无灌溉无施肥作为对照（CK）。研究菠萝光合面积、光合效率、干物质积累、经济性状、灌溉水生产力及肥料偏生产力对不同处理的响应。结果表明,补充灌溉施肥能够显著提高菠萝株高、叶长、叶宽、叶片数和植株干物质含量。水肥限制下,叶片数和叶长的减少是单株叶面积下降的主要因素,而光合面积的减小是干物质量下降的主要因素,菠萝植株生长受限来自于肥料减施和因干旱而导致的肥料利用受限。雨季干旱胁迫解除后叶片实际光化学效率（Φ_PSII）能够快速恢复,但营养生长期光合面积显著下降的不可逆转仍然导致果实干物质量和产量显著下降。补充灌溉施肥条件下肥料偏生产力表现为F₃>F₂>F₁,而果实田间产量和田间糖锤度均表现为F₃2≈F₁,因此确定F₂是最佳施肥水平;在F₂施肥水平下,水分生产力表现为W₂>W₁,但果实增产率和田间糖锤度在W₁和W₂之间差异不显著。因此,采用F₂W₂补充灌溉施肥方式可为菠萝生产中节水节肥和提质增效提供支撑。     

西瓜品种‘黑皮’对瓜蚜的抗性遗传分析

采用单株蚜量比值法室内鉴定与RAPD、SCAR标记相结合的方法,系统开展了西瓜品种‘黑皮’对瓜蚜的抗性遗传分析。结果表明,以‘黑皮’和‘花绿’为亲本的杂交F₁代对瓜蚜表现为抗性,自交F₂代植株表型出现抗感性分离,抗蚜与感蚜植株分离比经χ²测验符合3∶1分离规律,并用筛选获得的RAPD标记WO4₆₀₀和SCAR标记WO4-S₅₃₀验证了4个抗蚜品种、4个感蚜品种和10个F₂抗蚜单株、10个F₂感蚜植株。结果以‘黑皮’为亲本的西瓜抗蚜性由单显性核基因控制且能稳定遗传,‘黑皮’‘绿美人’‘黑美人’和‘惠兰’品种对瓜蚜具有良好抗性,‘花绿’‘凤光’‘蕙宝’和‘甜美人’品种则易感蚜虫。     

甘蔗F1群体构建及主要农艺性状遗传变异分析

分离群体是进行作物遗传图谱构建、性状遗传研究、性状调控关键基因挖掘和种质资源创新利用的重要基础。本研究利用‘崖城94-46’和‘新台糖22号’杂交获得了209个杂交单株,通过SSR标记鉴定真假杂种和剔除病死单株,获得了1个包含145个杂交后代的F₁群体。F₁群体主要农艺性状遗传变异分析表明,8个性状都存在双向超亲现象,变异系数范围为9.23%~56.78%,8个性状的频数分布均呈连续正态分布,均为由多基因控制的数量性状。相关分析和逐步回归分析表明,甘蔗丛重与株高、茎径和丛有效茎显著正相关,决定系数为0.92;丛糖含量主要由株高、茎径、锤度和丛有效茎4个因素决定,决定系数为0.94。研究结果为利用甘蔗F₁群体开展遗传研究奠定基础,同时为甘蔗育种中重点选择性状确定提供参考。     

散穗高粱和红壳苏丹草杂交F2代群体农艺性状的相关和聚类分析

[目的]探究高丹草主要农艺性状间的关系.[方法]以散穗高粱(母本)和红壳苏丹草(父本)进行杂交后自交获得的F2代群体为材料,对该群体200个单株的9个主要农艺性状进行变异、相关和聚类分析.[结果]各农艺性状间表现出明显的变异(10.00％～63.07％),总分蘖数和单株鲜穗重的变异系数最大,分别是63.07％、52.0...     

苦瓜叶片叶绿素含量的遗传分析

为探究苦瓜叶片叶绿素含量遗传特点,加快高产优质新品种选育进程,以苦瓜高代自交系$\otimes$04-17-6和$\otimes$25-6配组产生的6个世代P₁、P₂、F₁、B₁、B₂和F₂为材料,利用主基因+多基因混合遗传模型和ABC尺度测验2种方法,对苦瓜叶片叶绿素含量进行遗传分析。主基因+多基因混合遗传模型分析结果表明,叶绿素含量遗传受1对加性-显性主基因+加性-显性-上位性多基因控制,且高叶绿素含量对低叶绿素含量为不完全显性。3个分离世代B₁、B₂、F₂的主基因遗传率分别为2.86%、75.35%、79.79%,多基因遗传率分别为87.81%、0%、0%,环境变异为9.33%~24.65%,主基因的加性效应d_a和显性效应h_a分别为17.739和17.682,显性度h_a/d_a 小于1。ABC尺度测验结果表明,叶绿素含量的遗传符合加性-显性模型。2种方法分析结果表明,苦瓜叶片叶绿素含量由1对主基因控制,同时受微效多基因及环境影响,适合进行早代选择。B₂、F₂世代应重点进行主基因选择,多基因在B₁选择效率高,提高品系叶绿素含量应注重对加性效应和显性效应的利用。该研究结果为苦瓜产量及品质育种提供了理论基础。