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1.
Summary The relationship between the genetic distance of parents and both the heterosis of F1 hybrids and the variance of F5 lines was investigated in 72 crosses of pea (Pisum sativum L.). The genetic distance between each pair of parents was estimated, using isozyme (GDi), morphological (GDm) or quantitative (GDq) markers and finally a combination of isozyme and morphological markers (GDi+m). GDm was poorly correlated with the other measures of genetic distance, which in turn were strongly correlated with each other. Genetic distance was moderately correlated with the level of heterosis for yield over midparent in the F1 generation, with the highest correlation obtained from GDi+m. GD was not significantly correlated with heterosis for yield over the better or best parent but it was significantly correlated with all three measures of heterosis for pods per plant and hundred seed weight. There was no correlation between genetic distance and the level of heterosis for yield and total dry matter in the F2 generation, but GDi, GDi+m and GDq were predictive for the level of inbreeding depression in grain yield and total dry matter. When parents were high in genetic distance, crosses produced highly transgressive segregants for basal branches per plant, hundred seed weight, harvest index and onset of flowering. Genetic distance between parents was thus a useful measure for predicting a portion of hybrid performance and also of the variance of derived inbred lines. It was concluded that when choosing parents for a cross, consideration should be given to their genetic distance as well as their overall adaptation and their yield. There is considerable potential for optimising choice of parental combinations in the development of improved pea cultivars.  相似文献   

2.
棉花杂种优势与几种生理生化指标的相关性   总被引:12,自引:0,他引:12  
对8个陆地棉杂种及其亲本的四种生理生化指标进行了测定,并研究了这些指标与杂种产量优势的相关性,结果表明:幼芽匀浆互补法对F1皮棉超亲优势、中亲优势的预测相符率分别为87.5%和75.0%;杂种萌动种子ATP含量普遍高于双亲平均值。超亲优势、中亲优势与杂种ATP含量及双亲ATP含量的平均值均呈正相关,且中亲优势与杂种ATP含量相关显著(r=0.7188,P〈0.05);杂种产量优势与盛蕾期、盛花期的  相似文献   

3.
An investigation was carried out to assess the efficiency of A2 cytoplasmic-nuclear male-sterility (CMS) system in comparison to the widely used A1 cytoplasm in terms of general combining ability (gca) effects of male-sterile (A-) lines and mean performance, specific combining ability (sca) effects and mid-parent heterosis of hybrids for days to 50% flowering, plant height and grain yield at International Crops Research Institute for the Semi-Arid Tropics, Patancheru, Andhra Pradesh, India in 2001 and 2002 rainy seasons. The material for the study consisted of six pairs of iso-nuclear, allo-plasmic (A1 and A2) A-lines and 36 iso-nuclear hybrids produced by crossing these A-lines with three dual restorer (R-) lines. The results revealed that cytoplasm and its first-order interaction with year, R- and A-lines did not appear to contribute to variation in iso-nuclear hybrids for plant height and grain yield. Cytoplasm had limited effect on gca effects of A-lines and on sca effects and mid-parent heterosis of iso-nuclear hybrids for days to 50% flowering, plant height and grain yield. The mean days to 50% flowering, plant height and grain yield of A2 cytoplasm-based hybrids were comparable with those of widely used A1 cytoplasm-based hybrids. The relative frequency of the occurrence of the A1- and A2-based hybrids with significant sca effects and mid-parent heterosis indicated that A2 CMS system is as efficient as A1 with a slight edge over A1 for commercial exploitation. The implications of these results are discussed in relation to opportunities for broadening not only cytoplasm base but also nuclear genetic base of both the hybrid parents.  相似文献   

4.
Summary Ten experimental hybrids derived from the crossing of representative Italian pure-line varieties were grown at three locations in 1984–85. The amount of F1 seed produced from the crossings ranged from 1.5 up to 4 kg per plot of 20 m2. Hybrid purity was on average 88% when estimated through the growout test and 82% when estimated through acid polyacrylamide gel electrophoresis (A-PAGE) of gliadin.All the hybrids showed high-parent heterosis for plant height. Grain yield was higher in the hybrids (71.1 q/ha) than in the female parents (66.5 q/ha); the range of mid-parent heterosis being-10% to +17%. Four hybrids showed standard heterosis (yield advantage). The highest value (+6%) was obtained with the combinations Chiarano x Leopardo and Claudia x Leopardo. Among yield components, the number of spikelets/spike proved to be an important trait and may explain the superiority of the hybrids over the traditional varieties.The bread-making quality appeared intermediate to that of the parents or closer to that of the poorest parental variety.  相似文献   

5.
J. X. Shen    T. D. Fu    G. S. Yang    C. Z. Ma  J. X. Tu 《Plant Breeding》2005,124(2):111-116
Self‐incompatibility is one of the most effective approaches to utilizing heterosis in oilseed rape around the world. To evaluate the heterosis of double low self‐incompatibility, the possibility of combining seed yield and oil content, and the genetic effects of parents on their hybrid progenies, a 2‐year field trial using a 3 × 22 NC II mating design was conducted during the 1999‐2001 growing seasons in Wuhan, China. Significant differences in seed yield per plant and seed oil content were observed among the F1 hybrids and between F1 progenies and their parents. However, the heterosis for seed yield per plant was much greater than that for seed oil content. Mid‐parent heterosis and high‐parent heterosis of seed yield per plant ranged from 5.50 to 64.11% and from –2.81 to 46.02%, while those of seed oil content ranged from –1.55 to 7.44% and –3.61 to 6.55%, respectively. Non‐additive genetic effects were a major mechanism that accounted for the yield heterosis in addition to additive effects. In contrast, seed oil content heterosis was mainly dependent on an additive genetic effect. General combining ability (GCA) determined the stability of hybrid cultivars. In hybrid breeding, parental materials might be selected by the sum of GCAs and variances of special combining abilities (SCAs) of female and male parents for traits affected by both additive and non‐additive effects, and by the sum of GCAs of two parents for traits controlled mainly by additive effects. Primary branches and their siliques were the most important yield traits.  相似文献   

6.
A. R. McElroy 《Euphytica》1991,57(2):117-123
Summary A breeding program aimed at improving the seed yield in bean for processing was started. Six parents divergent in a range of agronomical characters were crossed according to diallel mating design. Cluster analysis performed on the composite cross population evidenced divergence between F1 hybrids and to maximize genetic recombination, the most different F1 hybrids were intercrossed. A Factor analysis was performed on 7 morphological and yield-determining traits of 15 hybrids F1 and parents. Three Factors, representing patterns of variables interpreted as productivity per plant, growth factor, and branching-productivity, were extracted. These results evidenced the inverse relationship between seed yield components (seeds/pod, pods/plant, and hundred seed weight): i.e. the selection for either variable is detrimental to the other. It may be possible to break this association if the plant construct assures high sink to satisfy all plant requirements: tall and large plants bearing numerous nodes, leaves and reproductive structures. Moreover, the selection practiced simultaneously on the yield components positively affected the seed yield trait. An index of selection and response to selection were estimated on the segregant populations. The realized gain in seed/yield reached after one cycle of selection (C1) was 6.5 g, about 20% over the base population (C0). The expected gain from selection based on the superior 5% plants in C2 families was 25.5% and approached the realized gain. The result of this paper gives evidence to support that the seed yield can be improved by an adequate selection intensity and selection index can be very useful when it is faced with the improvement of several traits at the same time.  相似文献   

7.
Saini  S. S.  Kumar  Ish  Gagneja  M. R. 《Euphytica》1974,23(2):219-224
Summary Heterosis for yield and four yield components, viz. panicle number per plant, panicle length, spikelet per panicle and 1000-grain weight, was studied in fifteen crosses involving six varieties of rice, Oryza sativa L. Positive and significant heterosis for yield was observed in 11 and 8 crosses, over the mid-parent and the better parent, respectively. Hamsa x Hybrid 27 gave the highest heterosis both over the mid-parent (156.23%) and the better parent (136.38%) followed by Jaya x Norin 18 with respective values of 155.18 and 56.29%.As compared with the average yield of 36.54 g per plant of the high yielding commercial variety, viz. Jaya hybrids in 8 crosses gave significant higher yield and four crosses, viz. Hamsa x Hybrid 27, Hybrid 27 x Jhona 349, Jaya x Palman 579 and Jaya x Hybrid 27, gave 80.51, 66.56, 57.11 and 56.30 g per plant, recording an increase of 120.33, 82.13, 56.29 and 54.08%, respectively. The heterosis for yield was due to simultaneous heterosis for a number of yield components. The possibility of hybrid crop production as compared with the recently developed high yielding rice varieties has also been discussed.Contribution No. 73.15 from the Department of Plant Breeding, Punjab Agricultural University, Ludhiana, India.  相似文献   

8.
采用经过初次测产、一次测产表现优良的20份杂交大豆品种作为试验材料,研究大豆杂交种杂种优势,结果表明大豆杂交种具有明显的杂种优势,参试的20份杂交大豆组合中比高产对照黑农38号增产的组合19个,增产幅度为2.39-61.33%,其中增产15%以上的组合11个,占参试组合的55%;增产2.39-14.76%的组合8个,占参试组合的40%;减产组合一个(-11.4%),占参试组合的5%。产量性状分析表明,不同性状变异程度不同。杂交种产量优势主要来自于三粒荚数、四粒荚数、单株荚数、单株粒数、单株产量、分枝数等产量性状。  相似文献   

9.
Parental lines, F1 and F2 hybrids from a 7×7-diallel of topless faba beans and eight standard cultivars were grown in single-rows for two years at four sowing dates on a highly fertile loam soil near Göttingen. In grain yield, F1 hybrids showed 21 to 54% advantage over the higher yielding parent. Compared with the midparental value an average heterosis of 50% was observed for grain yield. Corresponding heterosis mean values ranged from 3 to 37% for yield components and up to 11% for phenological traits. The grain yield of the highest yielding topless F1 hybrid was equal to that of Alfred, the highest yielding indeterminate standard cultivar. High grain yield in the topless hybrids was closely correlated with high biomass yield, late ripening and tall plants generally having a high number of podded nodes and pods on the main stem. Due to their agronomic advantages, i.e., lower plant length, reduced lodging sensitivity and earlier ripening, efforts at breeding topless hybrids seemed to be worth-while in faba beans. However, their yielding ability must be improved further before they can compete with normal, semi-dwarf and stiff-strawed cultivars.  相似文献   

10.
陆地棉显性无腺体品系杂种优势及配合力研究   总被引:5,自引:0,他引:5  
以7个显性无腺体陆地棉品系和4个常规品种(系)为材料,按NCI设计,对28个组合的杂种F1进行了分析。结果表明。杂种F1具有明显的优势,28个组合所研究的15个性状中全部具有中亲优势,6个性状具有高亲优势,4个性状具有竞争优势;配合力分析的11个性状中,株高、衣分、纤维长度和麦克隆值主要受基因加性效应控制,而子棉产量、皮棉产量、单株铃数、铃重和子指等性状同时受基因加性和非加性效应作用,显无073是丰产的显性无腺体品系,而显无260是较好的优良品系,组合显无073X泗棉2号在重要性上表现较好。  相似文献   

11.
为了研究大白菜中是否存在花粉直感效应,以14S116为母本,14S443、14S375、14S120、14S502、14S393、14S536为父本,配置杂交种;以14S193为母本,14S443、14S125、14S116、14S375、14S531为父本,配置杂交种;以92S24A为母本,8407、72M、Da T511、Da164-2-1、14S126、14S375、山东4号、芥菜、Da秦3为父本,配置杂交组合。测定杂交当代角果的果荚长、果荚宽、果喙长、种子形状、单荚种子数以及千粒质量,获得中亲优势、杂种优势和父本效应。另外,JY3与JY4、JY5与JY6、JY19与JY20、Bre与夏胜、92S24与夏胜、14S375与14S116进行互交,测定千粒质量,得到中亲优势、杂种优势和父本效应,并观测了部分组合的种子形状和种皮颜色。结果表明:花粉在杂交当代直接影响组合千粒质量、荚果的果荚长、果荚宽、果喙长、种子形状及单荚种子数,也表现出杂种优势和超亲优势。  相似文献   

12.
Summary One hundred and thirtysix hybrids were developed utilizing four cytoplasmic genetic male sterile lines (V 20A, Zhen Shan 97A, IR 46829A and IR 46830A) and 34 effective restorers. Heterosis, heterobeltiosis and standard heterosis were found to be significant for grain yield and other yield attributing characters in most of the hybrids. The heterosis for grain yield was mainly due to the significant heterosis for the number of spikelets per panicle, test weight and total dry matter accumulation. Interestingly, it was found that most of the higher yielding hybrids were accompanied by significant negative heterosis for harvest index. Hybrids shorter than the shortest parent and earlier than the earliest parent were not observed; hybrids with intermediate to tall plant height having nonlodging habit could be developed. Eighteen hybrids gave more than 20% grain yield than the standard checks. These were evaluated for their stable and consistent yield performance over four seasons. The results on analysis for stability parameters indicated that the hybrids V 20A × Himdhan and Zhen Shan 97A × Mahsuri were stable over environments.  相似文献   

13.
转基因抗虫棉产量性状的遗传效应及其杂种优势分析   总被引:2,自引:2,他引:2  
采用加性-显性与环境互作的遗传模型,分析了9个亲本和36个F1的皮棉产量、单株铃数、铃重和衣分的两年资料,估算了转基因抗虫棉各项遗传方差和成对性状间各项遗传效应的相关性.结果表明,转基因抗虫棉的产量性状受加性和显性效应共同控制,皮棉产量、铃重和衣分都以基因的显性效应为主,而单株铃数是以加性效应为主,单株铃数和衣分还具有基因与环境互作效应.遗传相关分析表明,转基因抗虫棉的皮棉产量与单株铃数的基因型和表现型相关系数都比较大而且比较接近;皮棉产量与单株铃数、铃重和衣分的加性相关系数都达到极显著水平,而且皮棉产量与单株铃数、衣分的数值比较大.利用亲本和F1的资料预测了F2基因型值和杂种优势,结果表明,转基因抗虫棉F2的皮棉产量、单株铃数、铃重和衣分的群体平均优势分别为4.0%、5.1%、-1.3%和3.2%,群体超亲优势分别为-7.3%、-6.0%、-4.2%和-0.5%.  相似文献   

14.
Cardamom is an important high value spice crop. Hybrid breeding is discussed for some time, but there is no information for cardamom. Eight genetically diverse cardamom lines were crossed in a diallel to evaluate the performance of hybrids and determine heterosis over mid-parent, better-parent and standard control for yield and yield components. The study was undertaken for a period of 3 years from 1988 to 2001 (Experiment I). Hybrids generally showed good overall performance for most of the characteristics compared with parents. Ten of the 56 hybrids significantly out-yielded the standard control (RR 1). Substantial mid-parent (MPH), better-parent (BPH) and standard (SH) heterosis were observed for the majority of the characteristics studied. Further evaluation of selected hybrids for yield and disease resistance during 2002–2007 (Experiment II) led to the identification of two cross combinations (CCS 1 × NKE 19 and RR 1 × NKE 12) with high yield and mosaic resistance. The study revealed that cardamom hybrids with high yield potential, desirable quality characteristics and mosaic resistance can be developed from appropriate parents through heterosis breeding. This is the first report of heterosis in cardamom for yield and yield contributing characteristics.  相似文献   

15.
红叶棉花的产量杂种优势研究初探   总被引:2,自引:0,他引:2  
利用综合性状表现较好的3个红叶材料作父本,与15个绿叶转基因棉花新品种(系)组配19个红叶杂交组合,研究了具有红叶标记性状棉花的产量杂种优势表现,结果表明:19个红叶杂交组合子棉产量具有明显的杂种优势,皮棉产量的具有正向中亲优势、正向超亲优势和负向竞争优势,衣分和单铃重具有正向的中亲优势,单株铃数表现正向中亲、超亲和竞争优势,筛选出产量竞争优势在5%以上、综合性状较好的优势组合4个。  相似文献   

16.
This study quantified the magnitude of heterosis in pearl millet (Pennisetum glaucum) topcross hybrids produced by crossing 16 diverse landraces and three high yielding open-pollinating varieties on two homozygous male-sterile lines. Hybrids and pollinators were grown in 12 year ×;location combinations in India that were grouped into three zones. Genetic components of variance quantifying the differences among these hybrids were estimated. The hybrids showed a conspicuous heterosis for grain yield, earliness and biomass yield but not for straw yield. The level and direction of heterosis for time to flowering depended strongly on the earliness of the male-sterile line. In the terminal drought stress zone hybrids made on the early maturing male-sterile line 843A had the highest level of heterosis for grain yield (88%). This was partly due to escape from terminal stress. In the other two zones the heterosis for grain yield was on average 30%. Heterosis for biomass yield and biomass yield per day was on average also positive in all three zones. For all traits, except time to flowering and biomass yield per day, pollinator effects were the only significant source of variation. Differences between hybrids were mostly caused by additive genetic effects. Significant amount of heterosis observed in landrace-based topcross hybrids for grain yield and other productivity-related traits suggested that substantial improvement in pearl millet productivity in and environments can be obtained by topcrossing locally adapted landraces on suitable male-sterile lines. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
研究了籼爪交和粳爪交杂种在长沙、三亚的农艺性状和干物质产量的杂种优势.在长沙的籼爪交杂种在结实率和每穗实粒数方面具有负向超亲优势,在每穗实粒数、结实率、单株粒重和理论产量方面存在负向对照优势,其余性状均为正向优势;粳爪交杂种在千粒重和结实率方面存在负向超亲优势,其余性状为正向超亲优势, 在始穗期、秆高和单  相似文献   

18.
陆地棉品种与陆地棉族系种质系间杂种优势及其组成分析   总被引:7,自引:1,他引:6  
游俊  刘金兰 《作物学报》1998,24(6):834-839
采用NCⅡ遗传交配设计,选用3个陆地棉常规品种和5个陆地棉族系种质系材料杂交,杂种F1代产量和纤维品质优势表现明显。通径分析结果表明,提高铃重,单株铃数的中亲优势,适当降低单铃种子数和株高的优势。在其它性状适宜的情况下,可以显著地提高皮棉产量的中亲优势。各个优势组合在产量优势来源上有差异。种质系材料在杂种优势利用上具有很大潜力。  相似文献   

19.
采用NCⅡ遗传交配设计,对5份标记型柱头外露种质系和3份陆地棉亲本交配后,杂种F1的11个性状的杂种优势和配合力进行了分析。结果表明,主要产量性状霜前皮棉产量,超高优势的幅度为-28.88%~13.17%,平均为-3.06%,6个组合具正向的杂种优势;中亲优势的幅度为18.14%~80.12%,平均为53.08%,15个组合均具有正向的中亲优势;竞争优势的幅度为-15.32%~46.43%,平均为11.27%,10个组合具有正向的竞争优势。其它产量性状中单株铃数的杂种优势最为明显。纤维品质性状,2.5%跨长和比强度的优势明显,麦克隆值的负向优势明显。高亲值、中亲值和低亲值与F1平均值的相关关系表明,多数产量性状F1代平均值与高亲值相关性密切,因此在组合筛选时应注意对常规亲本的选择。配合力上,GCA效应显著的性状,中棉所19和石321分别在产量、品质性状方面表现较优,96-1、96-67、96-33等3份标记型柱头外露种质系表现较优;SCA效应显著的8个性状中,A1B28个性状的SCA效应值均为正,A2B2和A4B1均有7个性状的SCA效应为正。文中对标记型柱头外露种质及亲本选配等问题进行了讨论。  相似文献   

20.
Summary Divergence of 25 accessions of Brassica juncea of Indian, CIS (Commonwealth of Independent States, former USSR) and synthetic origin was studied by D2 analysis. On the basis of divergence, ten accessions were selected and crossed in a diallel fashion without reciprocals to study the combining ability and heterosis. None of the accessions was found to be a good general combiner for all the nine quantitative characters that were studied. Significant heterosis over better parent for single plant yield was recorded in CIS x Indian and synthetic x CIS crosses (5 each) followed by Indian x synthetic types (3). The analysis of component characters showed that the mean performance of the majority of hybrids was intermediate for five out of six yield attributing traits, thus exhibiting dominance or partial dominance effect. To estimate the contribution of such yield attributing traits towards heterosis for yield, a comparison was made among three parameters viz. heterosis over mid parent (MP), better parent (BP) and better yielding parent (BYP) of the concerned hybrid. It was observed that estimation of heterosis from BYP was a more accurate method to determine the contribution of component characters towards yield heterosis than the analysis based on MP and BP. From the component character analysis, it was concluded that characters like number of primary and secondary branches, number of siliqua per plant and siliqua density contributed significantly towards heterosis in yield. Plot level yield trials of two selected hybrids (Skorospieka II x RH30 and Donskaja IV x Varuna) over two growing seasons revealed 29.4 to 91.8% heterosis over BYP.  相似文献   

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