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     

油用向日葵杂交种——吉葵杂一号

油用向日葵杂交种吉葵杂一号是三系杂交种,原名“A871-1XC871-1”。其亲本不育系A871-1由HA89A转育而成,保持系B871-1为NS-201-72的自交系,恢复系C871-1为索里姆82自交系。选育工作从1980年开始,1986～1987年该杂交种在校内选种圃和鉴定圃试验中表现综合性状优良,增产显著,     

不同花色观赏向日葵杂交后代主要观赏性状遗传规律研究

为了解不同花色的观赏向日葵杂交后代主要观赏性状的遗传规律,分别以舌状花黄色和白色的观赏向日葵为父母本进行正反交,F₁自交,获得F₂花色分离群体,分析2个群体后代花色及柱头色分离情况,并对株高、盘径、叶片数、舌状花瓣数、分枝数、柱头色及舌状花瓣色等7个性状进行遗传变异分析。结果表明,2个群体杂交后代F₁舌状花均为黄色,F₂均分离出4种花色,表明亲本黄色由多基因控制,属于数量性状和质量性状。F₁的柱头均为紫色,F₂分离出绿色和紫色,分离比例约为1:3,符合孟德尔遗传规律,柱头紫色是由独立等位基因控制的,属于质量性状,柱头紫色对绿色是完全显性;2个群体中超亲分离现象一致,其中分枝数和叶片数高于亲本范围,舌状花瓣数低于亲本范围,存在超亲分离现象;在中亲优势分析中,YW比WY群体中亲优势明显;F₂性状相关性表现基本一致,株高与花瓣数、分枝数和叶片数,盘径与花瓣数和分枝数,花瓣数与叶片数和分枝数,分枝数与叶片数,花色与柱头色之间均呈极显著相关性。通过对不同花色杂交后代重要观赏性状的遗传规律进行探讨,为观赏向日葵的育种工作提供借鉴。     

利用胞质雄性不育系生产萝卜优质良种的关键技术

萝卜是原产于我国的一种重要世界性蔬菜 ,其肉质根中含有人体所需要的多种营养成份。萝卜杂种优势明显 ,产量、品质、抗逆性、贮运性、整齐度等性状优于亲本。萝卜一代杂种可以通过自交系与自交系、自交不亲和系与自交不亲和系、雄性不育系与自交系间杂交等多种方式获得。我国利用萝卜雄性不育系配制一代杂种较为普遍 ,它具有遗传稳定、杂交率高、杂种优势强、亲本保纯及杂种生产操作简便等优点。利用萝卜胞质雄性不育系生产优质一代杂种的方法主要有大株制种、小株制种与中株制种。1　大株制种法1.1　优良亲本系的培育亲本有雄性不育系、保…     

水稻核不育系柱头性状的主基因+多基因遗传分析

柱头性状是影响水稻不育系异交繁殖和杂交水稻制种产量的重要性状。为创制长柱头、高外露率的水稻温敏核不育系提供遗传信息,调查了短柱头、低外露率的粳型光温敏核不育系7001S和长柱头、高外露率的温敏核不育系紫泰S及其杂交、自交获得的F_1、F_2群体(350个株系)和F_2:3群体(320个株系)的4个柱头性状,分析了4个性状之间的相关性,并运用主基因+多基因混合遗传模型,对2个世代4个性状进行了遗传分析。结果表明,4个柱头性状间均表现出极显著正相关,相关系数介于0.262和0.895之间。柱头长度、花柱长度、柱头和花柱总长度(以下简称柱花总长度)均表现出受2对主效基因和微效基因共同控制,除F_2群体中柱花总长度的2对主基因表现为等加性效应和等显性效应外,其余均表现为加性-显性-上位性效应,3个性状均表现出以主基因间的上位性效应为主;F_2群体柱头外露率受2对加性-显性-上位性主基因+多基因控制,而F_2:3群体则表现为受1对加性-显性主基因+多基因控制,以主基因间的加性效应为主。2个世代中的4个柱头性状均以主基因遗传为主。     

青海独一味在低海拔移栽地传粉及结实率的研究

目的:研究独一味在低海拔移栽地的结实率。方法:将独一味根茎芽从海拔4 300 m的野生地移栽到海拔为2 366m和3 100 m的多巴及大通实验基地,研究其在移栽地的花粉活力,花粉在柱头上的萌发及自然结实率。结果:独一味在移栽地花粉活力较低,柱头上没有花粉及花粉管的萌发,在栽培地的自然结实率为0。结论:独一味在移栽地传粉效率和结实率都较低。     

玉米叶片保绿度遗传主效应及其与环境互作的遗传分析

研究不同环境条件下玉米叶片保绿度性状的遗传主效应及其与环境互作效应;采用朱军提出的基因型×环境互作效应的加性-显性-母体效应遗传模型(ADM模型)分析方法;结果表明玉米叶片保绿度的遗传除了受制于基因的加性效应(VA)、母体效应(VD)遗传主效应外,还会明显受到显性效应×环境互作效应(VDE)的影响.组配杂交组合时根据各亲本的遗传效应预测值,选用遗传主效应表现良好以及在不同环境下互作效应表现正向较为稳定的优良亲本做母本,提高选择效果;自交系沈137具有较高的正向加性效应和母体效应,是选育保绿性玉米较好材料.     

抗列当向日葵品种(系)植物学性状对产量预测模型的影响

以8个抗列当食用型向日葵品种(系)为材料,运用多元相关分析及通径分析法,对向日葵经济特性、生理特性、子粒特性与产量(CL)的相关性进行了分析,在此基础上构建抗列当向日葵产量预测模型,并量化模型中各性状指标对产量的直接和间接影响效应。结果表明,向日葵产量同时受多因素影响,但不同抗列当向日葵品种(系)产量的主导影响因子有所不同;各植物学性状对产量的影响不仅表现在本身具有的直接作用,同时还表现在通过其他性质体现出的强烈间接影响效应;剔除种间因素影响后,单盘粒重(DPLZ)、结实率(JSL)、百粒重(BLZ)、株高(ZG)、粒宽(LK)及盘径(PJ)等6个植株性状成为抗列当向日葵产量模型Com-MODEL(CL=-6.023+0.014DPLZ+0.06JSL+0.328BLZ+0.014ZG-4.571LK+0.156PJ)的主要变量,该模型能解释86.9%的CL变异;其中粒宽、百粒重及盘径对CL的影响都达到了极显著(P0.001)或显著水平(P0.01);各变量对产量预测模型R2的总贡献计算结果显示,粒宽、百粒重及盘径通过直接作用和间接作用成为影响向日葵产量变化的3个主导因素,共同决定了CL的大部分变异;其次是单盘粒重及结实率的影响;株高对CL的影响很微弱。     

糯玉米籽粒体积双列杂交分析

为了解糯玉米自交系籽粒体积性状配合力表现及体积性状世代间遗传规律,指导大粒型杂交组合选配及自交系改良,通过选用生产上推广的杂交种亲本及本单位选育的自交系共10份,按完全双列杂交配制组合,随机区组种植于大田,籽粒完熟晒干对体积进行测定,用Griffing IV方法对数据进行处理,研究杂交组合间籽粒体积变化规律。结果表明:籽粒体积性状一般配合力效应在亲本间存在显著差异,S10一般配合力最好,S6一般配合力最低。特殊配合力效应在组合间差异显著。控制籽粒体积性状的基因狭义遗传力较低(hn2=12.55%),遗传效应中显性效应(VD=1.5398)大于加性效应(VA=0.7949)。试验表明:育种上针对籽粒体积性状选择,自交系应晚代选择为主,组合根据体积表现结合育种目标直接选择。     

优质蛋白玉米籽粒性状的遗传效应

选用8个胚乳性状差异显著的优质蛋白玉米(QPM)自交系, 采用Griffing I交配设计组配, 通过对亲本、F₁和F₂的鉴定, 探讨主要籽粒性状的遗传效应和杂种优势, 为有效利用热带硬质QPM种质改良、扩增我国温带QPM种质以及QPM籽粒性状改良和硬质QPM品种选育提供依据。结果表明, 籽粒百粒重、百粒体积、胚乳修饰度和籽粒密度在F₁和F₂代都表现一定的正向杂种优势; 胚乳修饰度在F₁代存在正反交差异, 母体效应明显; 4个性状的F₂代表型值与中亲值的相关性最大; 百粒重和百粒体积主要受母体效应控制, 基因效应以显性效应为主; 胚乳修饰度主要受种子直接效应控制, 基因效应以加性效应为主; 籽粒密度主要受母体效应控制, 基因效应以加性效应和显性效应同等重要。这4个籽粒性状的细胞质效应均较小, 主要受核基因控制。     

Study of morpho-physiological, phenological and reproductive behaviour in protogynous lines of Indian mustard [Brassica juncea (L.)]

Understanding the relationship between floral and reproductive traits are critical to understand the evolution of plant species in brassica and need for selecting lines as parental lines in hybrid seed prodcution. The protogyny nature of Brassica species are characterized based on the variations in floral morphology, protogyny interval, stigma receptivity, pollen biology, compatibility and seeds set. The variation in stigma morphology features (stigma exsertion prior to anthesis) and protogyny interval (ranged from 8 to 10 days) formed phenotypically distinct. Studies on stigma receptivity and pollen viability revealed significant variability and found to be at its peak up to 3 days after anthesis and reduced drastically thereafter. Compatibility crosses and post pollination events such as pollen deposition on the surface of the stigma and culminating with the entry of the pollen tube into the embryo sac, was rapid and completed within 2 days after pollination, whereas in in-compatible cross not even single pollen was germinated on stigmatic surface and consequently no pollen tube growth even after sixth day of pollination. In compatible crosses average seed set ranged from 3 to 8 seeds per pod from cross pollination and no seed set in self. The investigation revealed that variation exists for protogyny interval, stigma receptivity and compatibility in the protogynous lines of Indian mustard and this can be exploited for the production of hybrids without emasculation.     

Floral morphology affects seed productivity through pollination efficiency in radish (<Emphasis Type="Italic">Raphanus sativus</Emphasis> L.)

To examine the effect of stigma position and size on seed productivity through pollination efficiency in radish, the numbers of self and cross pollen grains on the stigmas and the seed productivity under insect-pollination were compared among four bred lines. Lines with a small stigma or a high stigma relative to the anthers on long stamens tended to receive fewer self and total (self + cross) pollen grains but showed a higher cross-pollination percentage (ratio of cross pollen grains to total pollen grains on stigmas) than those with a large stigma or a lower stigma. Additionally, a higher cross-pollination percentage was associated with a higher outcrossing percentage. This result suggests that variations in the two stigma traits affect the outcrossing percentage via the cross-pollination percentage. Therefore, it should be possible to prevent loss of F₁ purity by selecting new parental lines with floral morphology that favors cross-pollination percentage.     

Compatibility and fruit-set in cashew (<Emphasis Type="Italic">Anacardium occidentale</Emphasis> L.)

Understanding complex factors controlling yield is very crucial to the improvement of cashew in major producing countries currently experiencing very low yield and consequently making cashew farming unprofitable and the whole industry unsustainable. Eleven cashew clones were evaluated for their compatibility and fruit set between 2000 and 2002 seasons, in a diallel cross using randomized complete block design with three replications. Data collected on number of fruit set at 6 weeks after pollination were statistically analyzed. Significant differences between the parents at the 1% level, revealed the existence of variability for compatibility and fruit set, with 34% cross-compatibility, 51% partial cross-compatibility and 15% cross-incompatibility recorded, while 37% of the parents were self-compatible. Parents sharing the same apples colors tend to be highly cross-compatible, while some clones showed evidence of unilateral compatibility. Maximum value of 55% fruit set obtained from cross-pollination probably indicates upper limit for fruit set in cashew. Significant correlation between compatibility and variation in fruit yield suggests the important role of parental compatibility in selection of planting materials for the establishment of cashew plantation.     

杜鹃花属植物种质创新研究进展

杜鹃花是中国传统十大名花之一,栽培历史悠久,具有较高的观赏价值。相对于中国丰富的野生杜鹃花资源,国内杜鹃花种质创新进展缓慢。目前杂交育种仍是杜鹃花属植物种质创新的主要技术手段。杂交亲本的选择、正反杂交(向性)、杂交亲本的亲缘关系及系统分类地位等都会影响杂交的亲和性,因杂交亲和性的差异,受精障碍可能发生在受精前、后的各个不同阶段。针对受精前、后障碍,可以通过不同的授粉方法、杂交组合的合理配置,结合胚拯救技术,克服受精障碍,提高杜鹃花属植物的育种效率。虽有杜鹃花多倍体育种的相关研究报道,但人工诱导的多倍体商业品种还比较少见。秋水仙素(Colchicine)、氨磺灵(Oryzalin)、氟乐灵(Trifluralin)等在杜鹃花多倍体诱导中都有应用,杜鹃花多倍体在观赏特性上表现出叶片肥厚、花大等性状,一般对逆境胁迫的生长适应性也会提高,但也有杜鹃花多倍体抗性减弱的报道。多倍体可以帮助恢复杂交亲本育性,作为杂交亲本进行远缘杂交,有利于提高远缘杂交亲和性,采用异源多倍体可以克服因远缘杂交带来的缺少成对染色体配对而导致的杂种不育等问题。杜鹃花的转基因工程中,主要以农杆菌介导法和基因枪法为主,其中农杆菌介导法的基因转化率较高。本综述结合国内外的研究报道,对相关研究概况方面展开全面论述,以期为后期的杜鹃种质创新研究提供理论依据和技术支撑。     

Inter-accession variation in floral morphology in radish (Raphanus sativus L.)

We investigated variation in floral morphology among 36 accessions of radish (Raphanus sativus L.). We found wide, continuous inter-accession variation in 15 traits related to the size of the floral organs and the stigma position relative to the anthers of long stamens. A principal-component analysis of the 15 floral traits also showed wide variation among accessions. A large proportion of this variation was accounted for by lengths of stamens and the petal tube. In addition, the phenotypic stabilities with respect to the macro-environment (as affected by different sowing dates) and the micro-environment (among the flowers within a plant) differed between traits. Correlation analyses using all traits suggest the existence of genetic linkages or pleiotropies among floral organs. Our results indicate that floral morphologies varied greatly among radish accessions and they could be affected by the macro- and micro-environment. To explore the relationship between floral morphology and pollination efficiency, we compared the number of pollen grains deposited on the stigmas in the presence and absence of insect pollinators using three accessions with very different floral morphology. Because an accession with a higher stigma position than anthers might avoid self-pollination and an accession with a large stigma size received more pollen grains, floral morphology may affect pollination efficiency. Because the effect of pollination efficiency on seed production is well known, our results suggest that radish floral morphology affects seed production through its effect on pollination efficiency.     

Crossability of American tree peony ‘High Noon’ as seed parent with Japanese cultivars to breed superior cultivars

The tree peony (Paeonia suffruticosa Andr.) is a valuable ornamental plant. American and French cultivars have desirable flower colors, while, Japanese cultivars have larger flowers with better presentation. We hybridized an American tree peony cultivar ‘High Noon (HN)’ (the seed parent) with 57 different Japanese cultivars (pollen parents) to investigate cross compatibility, with the ultimate goal of obtaining improved hybrids. Of the 1,927 crosses performed, 135 (38 cross combinations) yielded a total of 181 seeds (86 mature) and 22 seedlings. Five of the hybrids have already flowered and exhibited their parent character with large yellow flowers. To investigate the causes of cross incompatibility, we examined pollen tube growth in a cross between ‘HN’ and a Japanese cultivar. The result indicated that there are three most important causes of incompatibility, namely, abnormal pollen tube growth, the failure of fertilized ovules, and poor seed germination. Although cross compatibility in each combination was low, crosses between ‘HN’ and Japanese cultivars might be successful with the right paternal plants. In this study, 13 Japanese cultivars had higher cross compatibility with ‘HN’ than the others. Our results will enhance tree peony breeding and guide the selection of parents for hybridization.     

The effect of gibberellic acid on fruit and seed set in crosses of garden and winter hardy Rosa accessions

Summary The effect of gibberellic acid (GA₃) was studied on a wide range of crosses between various garden roses and two hardy breeding lines. Although there were fewer seeds per fruit, fruit set was higher in most crosses when GA₃ was applied to the stigma at the rate of 250 ppm ten days after pollination. However, higher fruit set did not result in more seeds per pollination for many crosses and seemed to be related to the degree of male parentage. Both parents used had a major effect on pollination success. Recently developed Rosa cultivars have a narrow genetic base and the use of distantly related cultivars as parents would possibly give a high seed set and greater numbers of progeny.Contribution No. 335/90.08.01R, Experimental Farm, L'Assomption; Contribution No. Ro 44, Research Program Service, Ottawa.     

Overcoming pre-fertilization barriers in the wide cross between Chrysanthemumgrandiflorum (Ramat.) Kitamura and C. nankingense (Nakai) Tzvel. by using special pollination techniques

In our earlier study, pre-fertilization barrier was one of the main factors causing the failure of the wide hybridization between Chrysanthemum grandiflorum ‘Yuhuaxingchen’ and C. nankingense, and seriously restricted the utilization of the excellent chrysanthemum germplasm, C. nankingense. In order to overcome the pre-fertilization barrier and obtain some hybrids, we carried out wide hybridization between them again in this study, and tentatively adopted three pollination techniques including mentor pollen, delayed pollination, and gibberellic acid treatment. The average number of pollen grains germinating on stigma at 24 h after pollination and the percentage of embryo were investigated with a temporary mount method and the technique of fluorescence microscopy. It was found that, compared with the control, delayed pollination, gibberellic acid treatment, and mentor pollen significantly increased the average number of pollen grains germinating on each stigma at 24 h after pollination by approximately 152, 235, and 182%, respectively. In addition, all the three pollination techniques significantly increased the percentage of normal embryos at different periods after artificial pollination in comparison to the control. Furthermore, seed sets of the crosses using the three special pollination techniques were 1.1, 1.4, and 2.0%, respectively, whereas we did not obtained any seeds in the control. Taken together, these results suggest that delayed pollination, gibberellic acid treatment, and mentor pollen are three useful pollination techniques for overcoming pre-fertilization barriers and increasing seed set in the wide hybridization between C. grandiflorum ‘Yuhuaxingchen’ and C. nankingense, and they may be widely applied for increasing breeding efficiency in other chrysanthemum wide hybridization facing similar pre-fertilization barriers.     

花期喷盐水结合蜜蜂授粉克服大白菜自交不亲和性试验

大白菜花期喷ＮａＣｌ溶液，结合蜜蜂授粉克服自交不亲和性的试验结果表明，喷３％ＮａＣｌ溶液效果最佳；于上午９：３０喷结籽最多；每天早晨喷３％ＮａＣｌ后在不同时间进行人工授粉均可结籽；ＮａＣｌ处理株的花粉授粉效果好于未处理株，用于授粉的蜜蜂在使用前需隔离４天，以使身上的花粉失活。ＮａＣｌ处理后的柱头乳突细胞胼胝质含量的变化与亲和性变化有相同趋势。