首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Phenotypic and genotypic variation for seed yield and associated traits (heading date, plant height, number of fertile tillers, 1000‐seed weight, panicle length, seed weight per panicle, fertility, flag‐leaf length and flag‐leaf width) were studied in a full‐sib family of meadow fescue using replicated clonal trials at two locations in Norway. Genotypic variances were highly significant for all traits and genotype × location interactions were significant for heading date, number of fertile tillers and seed yield. Seed yield and other seed component traits exhibited the largest genotypic variations. Heading date showed large genotype × location interaction, probably because of the very diverse origin of the two parents of the full‐sib family. Path coefficient analysis showed that panicle fertility, measured as seed weight per unit length of panicles, was by far the most important component trait contributing to seed yield, followed by the number of fertile tillers, plant height and flag‐leaf width. Flag‐leaf width and plant height had sizeable indirect effects on seed yield via panicle fertility. This is the first time that the importance of the size of the flag leaf for seed yield in herbage grasses has been demonstrated.  相似文献   

2.
通过对以温敏亚麻雄性不育系1S为母本配制的6个杂交组合F1、F2代主要农艺性状和产量性状杂种优势的测定和分析,结果表明:不同杂交组合F1、F2代在株高和工艺长度上的平均优势均表现为负向超父本优势,而各产量性状上的平均优势均表现出很强的正向超父本优势;但与F1代相比,F2代平均优势明显下降。产量性状构成因素平均优势大小顺序为:单株产量>单株果数>千粒重>每果粒数。不同组合间F1、F2代杂种优势表现差异较大,其中1S×黑亚15号组合产量性状的超父本优势最强,F1、F2代均表现出很强的杂种优势。  相似文献   

3.
Path analysis was performed on plant characters of six safflower genotypes grown in a two year field experiment to determine for seed yield, the direct and indirect effects of the following traits: total biomass, stem yield, number of primary branches/plant, number of secondary branches/plant, number of seeds/m2, number of seeds/capitulum, number of capitula/plant, capitulum diameter, 1000-seed weight, seed weight/capitulum, distance between ground level and the first fertile branch, plant height, number of days to the beginning of branching, number of days to the beginning of flowering, number of days to 50% flowering, number of days to full flowering and flowering duration. Seed yield was significantly correlated with the following traits: total biomass, stem yield, capitulum diameter, 1000-seed weight, seed weight/capitulum, distance between ground level and the first fertile branch, number of days to the beginning of branching and flowering duration. Total biomass, seed weight/capitulum, distance between ground level and the first fertile branch, 1000-seed weight and flowering duration had substantial direct effects, in that order, on enhancement of seed yield. The significant positive correlation coefficient of capitulum diameter with seed yield resulted from positive indirect effects of total biomass, seed weight/capitulum and 1000-seed weight. Conversely, the significant negative correlations between number of days to the beginning of branching and distance between ground level and the first fertile branch and seed yield resulted from negative indirect effects of the same three traits. Stepwise multiple regression analysis showed that 94% of the total variation in seed yield could be explained by variation in total biomass and by number of days to the beginning of branching (84 and 10%, respectively). Results suggest that total biomass and number of days to the beginning of branching are primary selection criteria for improving seed yield in safflower.  相似文献   

4.
Experiments were conducted with early segregating generations of a selected narrow-leaf lupin cross to determine the effectiveness of selection for yield based on alternative criteria. F2 plants were selected on the basis of seed yield and several other yield-related characters to generate separate F3 populations. Randomly selected plants from each population were grown over the summer (off-season) in a glasshouse to generate F4 populations. Analyses of relationships between F2 plant measurements and F3 progeny mean yields revealed significant correlations only for those characters with the highest heritabilities - flowering time, 100 seed weight and harvest index. However, selection for the earliest flowering F2 plants followed by selection within this group of plants with the highest number of pod bearing branches would result in the greatest increase in F3 mean yield. The F2-derived F4 populations with the highest seed yields were those obtained by selection for total plant dry weight, number of pod bearing branches and number of pods per plant. Improvement in commercial crop yield should therefore be obtained through selection in early generations for those characters contributing to the greatest number of pods per unit area. A scheme involving selection for early flowering and high number of pod bearing branches in the F2 combined with replicated yield tests in the F4 is proposed.  相似文献   

5.
178 common vetch (Vicia sativa L.) strains were tested for 2 years under dryland conditions in Bursa, Turkey. Broad-sense heritability of the traits was calculated for each trait. Phenotypic and genotypic correlation coefficients between seed and straw yield, with several morphological and reproductive traits, were obtained. Broad-sense heritability estimates were high for 1000-seed weight and number of seeds per pod. Heritability values for both seed and straw yield were small and insignificant. Harvest index, 1000-seed weight and spring vigour showed significant positive correlations with seed yield, but days to flower correlated negatively with seed yield. Spring vigour, plant height and number of leaflets per leaf correlated positively, while harvest index, seeds per pod and seeds per plant correlated negatively with straw yield. Correlations between seed and straw yield were both positive and significant.  相似文献   

6.
以辽宁稻区典型的直立穗型品种辽粳5号与日本典型的优质米品种秋田小町杂交构建的重组自交系群体(recombination inbred lines, RIL)为试材,在高氮和低氮2种施肥模式下种植,调查RIL群体茎秆维管束、穗部和产量性状,分析减氮对三者的影响及其相互关系,探讨在减少氮肥施用量的同时维持产量稳定的可能途径。研究结果表明,不同施氮模式下,RIL群体的茎秆维管束性状、穗部及产量性状均呈现连续变异,符合多基因控制的数量性状遗传特点。氮肥减施后, RIL群体水稻的单茎穗颈和倒二节间维管束数目、单株穗颈和倒二节间维管束面积减少,一次枝梗数减少,一次和二次枝梗结实率、总体结实率和千粒重增加,单穗重增加,穗数减少,产量降低。茎秆维管束性状与穗部和产量性状关系密切,单茎维管束性状与穗颈粗、一次枝梗数、二次枝梗数、穗粒数、着粒密度、千粒重和单穗重大多呈显著至极显著的正相关,单株维管束面积与穗数和产量呈极显著正相关。氮肥减施后,RIL群体中不减产类型株系的主要特征是:低氮条件下仍能维持稳定的分蘖和茎秆维管束的分化,保证穗数和穗颈粗稳定,单茎穗颈和倒二节大、小维管束数目、单茎倒二节大维管束面积和单株倒二节大维管束面积无显著变化,一次枝梗数变化不显著。在减施氮肥的条件下,选用茎秆维管束发达,穗数和穗颈粗稳定的水稻品种,有可能实现减氮不减产的目标。  相似文献   

7.
Brasisca Juncea , cv. Pusa Bold, and B. campestris , cv. Pusa Kalyani, were raised under field conditions with varying levels of N supply from 0–120 kg ha-1. The production profile of branches and pods thereon was measured, per unit area basis, throughout the crop ontogeny. At maturity, data on the yield contributing characters, viz. pod dry weight, pod number, seed number per pod, 1000 seed weight, seed wall ratio and seed yield in different order branches, was recorded.
The branching pattern and the number of pods produced on different order branches, in the two species, was favourably modified by the increasing levels of N supply. Primary and secondary branches contributed to the seed yield to an extent of 80 % of the total yield. Nitrogen treatment had no significant effect on 1000 seed weight. B. juncea exhibited significantly higher yield over B. campestris. N supply up to 120 kg ha -1 linearly increased seed yield in both the species. However, it exerted a negative effect too partitioning of assimilates from pod wall to seed. The study indicated that rapeseed-mustard, grown under short winter-season environment with adequate soil moisture, has the potential for higher N-fertilizer optima exceeding 120 kg ha -1.  相似文献   

8.
密度对红豆草农艺性状和种子产量的影响   总被引:2,自引:2,他引:0  
为了合理利用空间资源,提高红豆草种子产量,试验以奇台红豆草为材料,设置不同的种植密度,通过对株高、分枝数、荚果数、千粒重、种子产量等指标的测量,探寻密度与红豆草生殖格局的关系。试验结果表明,种植密度30 cm×25 cm时,单株花序数、荚果数、千粒重和种子产量最高,依次是81.1个、839.2个、23.8 g、1995.8 kg/hm2。通过相关性分析,种子产量与千粒重呈显著正相关,相关系数为0.631;种子产量与单株荚果数呈极显著正相关,相关系数高达0.998。  相似文献   

9.
利用混合线性模型分析绿豆主要农艺性状的遗传及相关性   总被引:4,自引:0,他引:4  
以19个绿豆品种(系)为亲本, 采用非完全双列杂交试验设计及混合线性模型,研究绿豆主要农艺性状的遗传规律及其性状间的相互关系。结果表明, 绿豆全生育日数、株高、主茎节数和百粒重均以加性效应为主, 狭义遗传率较高且达极显著水平;单株荚数、单株产量和总产量的加性效应和显性效应均显著或极显著, 狭义遗传率相对较低;单荚粒数主要受显性效应影响, 广义遗传率较高;播种至开花天数与株高间存在显著或极显著遗传和表型正相关;单株荚数、单荚粒数与百粒重显著或极显著负相关;单株荚数与单株产量、总产量显著或极显著正相关;百粒重与单株产量、总产量相关性不大;针对全生育日数、株高、主茎节数和百粒重的选择可在早期世代进行, 而对产量的选择可以根据单株荚数和单株产量在晚期世代进行。  相似文献   

10.
Summary The effects of 1000-grain weight, its stability and the correlation coefficients with other traits of 50 barley varieties were studied at 18–20 environments. Additional material was used to study genotypic correlations among traits. Significant differences in stability of 1000-grain weight were found among varieties. Two-row varieties were on average more stable than 6-row varieties. The 1000-grain weight was among the most stable and grain yield the most variable traits. This was discussed in connection with stem reserves translocation to the grain. Consistently high yielding varieties had around average stability of 1000-grain weight. Regression coefficient, b, for 1000-grain weight was positively correlated with variance of log transformed data, both valid estimates for stability of 1000-grain weight. The correlation coefficient of 1000-grain weight with grain yield was positive or non-significant, with number of grains per tiller mainly negative and with volume weight it was positive. In 6-row barley, 1000-grain weight was positively correlated with grain yield, straw yield, total biological yield, and plant height, and negatively with number of tillers per m2 and number of grains per tiller.  相似文献   

11.
采用程氏指数法研究的结果表明:水稻亚种特性与经济性状有一定相关性,其中与结实率呈极显著正相关,与株高、穗数、穗重呈显著相关;亚种特性特别是与一次枝梗的各项性状如个数、千粒重、粒数、结实率,二次枝梗的二次粒率有密切相关性。亚种特性与穗颈大维管束数、小维管束数均呈极显著相关。  相似文献   

12.
Summary Fourteen lines of linseed (Linum usitatissimum L.) were evaluated for general and specific combining ability through line × tester cross analysis using five diverse testers in two different environments. Seventy F1's and nineteen parental genotypes were raised in completely randomized block design with two replications with respect to yield and yield related traits. Considerable genetic variation was observed for all the traits studied. The additive as well as non-additive gene effects played significant role in the inheritance of yield and related traits with preponderance of non-additive gene effects for all the traits studied. Higher proportion of general combining ability × environment interaction variance as compared to specific combining ability × environment estimates was recorded. Additive genetic variances were more sensitive than non-additive genetic variances to the changing environment. Low estimates of heritability (narrow sense) for primary branches per plant, capsules per plant, seeds per capsule, seed yield per plant, harvest index and oil content and medium heritability for days to 50% flowering, days to maturity, plant height and 1000-seed weight was observed. Among the female parents LCK-9816, Parvati, Himalini, KL-168 were good general combiners for yield and related traits along with oil content, whereas among male parents, Surbhi and KL-224 were good general combiners for yield related traits and oil content but KL-221 was good general combiner for seed yield and related traits.  相似文献   

13.
J. S. Chauhan    M. K. Tyagi    A. Kumar    N. I. Nashaat    M. Singh    N. B. Singh    M. L. Jakhar    S. J. Welham 《Plant Breeding》2007,126(4):399-402
Effects of drought on yield and yield components were investigated during the spring season 2000–2001 by growing 14 Indian mustard genotypes under irrigated and rain-fed conditions at Bharatpur and Jobner. A disease and pest management schedule was followed when required. The drought susceptibility index (DSI) for seed yield and component characteristics was calculated to characterize the relative tolerance of genotypes. Plant height, primary branches, secondary branches per plant, 1000-seed weight and seed yield were reduced under rain-fed conditions. The top five genotypes at Bharatpur that showed tolerance to moisture stress for seed yield, as indicated by their lowest DSI, were, in descending order PSR-20, PRO-97024, JMMWR-941, IS-1787 and PCR-7, whereas at Jobner these were JMMWR-941, RC-1446, PSR-20, RH-819 and 'Varuna'. Of these, PSR-20 and JMMWR-941 were among the top six at both locations. These genotypes also showed relatively low DSI for one or more characteristics, such as primary branches per plant, secondary branches per plant, harvest index and seed : husk ratio. Genotypes with the lowest DSI, particularly for seed yield at both locations, would serve as useful donors in the breeding programme for improving the drought tolerance of existing Indian mustard cultivars.  相似文献   

14.
探明不同盐逆境水平对耐盐水稻穗部性状及产量构成因素的影响,旨在为沿海滩涂水稻种植和耐盐水稻高产育种提供科学依据.以'扬农稻1号'(V1)、'南粳5055'(V2)和'通海粳18-2'(V3)为试材,利用盐池设施设置O g/kg(S0)、1.5 g/kg(S1)、3 g/kg(S2)3个不同盐分水平,采用裂区试验,测定分...  相似文献   

15.
为了新疆亚麻地方种的选育和改良提供理论依据,本研究采用对来自新疆各地的亚麻地方种性状的多元统计分析,包括变异系数、主成分分析、相关性分析和聚类分析。结果表明,新疆亚麻地方种资源存在较大差异,多样性比较丰富。主成分分析中,株高会影响构成亚麻产量的因子(蒴果数,果粒数,每株粒重和千粒重),亚麻的分枝数和株高都不能过多或过高,这不仅会影响工艺长度还会影响亚麻产量因子而且发现株高、生育期、分枝数、工艺长度、每株粒重、分枝数、千粒重和果粒数的相关程度较高。因此,在新疆亚麻地方种在选育时,可作为理论性数据参考,为亚麻品种选育和亲本的选择提供一定基础。  相似文献   

16.
Paolo Ranalli 《Euphytica》1996,87(2):127-132
Summary The effect of a recurrent selection procedure for improving seed yield per plant was evaluated in common bean. Progress was registered after three cycles of recurrent selection with S2 progeny evaluation performed on the grain yield/plant. Gain from selection was estimated by field testing 45 random S2 lines from each of the C0, C1 and C2 populations. Response to selection for seed yield/plant was 6 g from C0 to C1 and 4.4 g from C1 to C2. The seed yield improvement was due principally to an increase in pods/plant; little contribution was provided by the 1000-seed weight and seeds/pod traits. Broad-sense heritability and genotypic variance for grain yield remained high in all cycles which suggests further gain from additional selection cycles. Grain yield/plant is significantly correlated to pods/plant and seeds/pod traits in all cycles, indicating that plants with favourable combinations of these traits could be identified. The proposed recurrent selection procedure appears to be effective in improving the population and extracting superior genotypes for varietal development.  相似文献   

17.
Summary To determine the levels of heterosis in F1 hybrids, four current pea (Pisum sativum L.) cultivars from southern Australia were used as female parents and crossed with 18 introduced genotypes. The 22 parents, 72 F1 hybrids and, depending on the environment, either 54 or all 72 F2 families were grown in replicated plots in four environments. Grain yield, total dry matter, harvest index, branches per plant, pods per plant, seeds per pod, hundred seed weight, plant height, onset of flowering and flowering periods were evaluated. For both the F1 and F2 generation, heterosis was determined as the superiority over the mid-parent and also over the better parent. In addition, the superiority over the best commercial cultivar was calculated. Most hybrids were higher yielding than their mid-parent but were less stable in yield across environments. Four F1 hybrids were significantly higher yielding than the best parent, by up to 26%. There were significant correlations between F1 hybrid and mid-parent value for plant height, pods per plant and hundred seed weight but not for yield. Overall, grain yield heterosis was mainly due to more pods per plant in the hybrids. The level of heterosis for yield in a poor yielding environment was higher than that in a high yielding one. Both additive and non-additive gene effects were important in the expression of all studied traits. The average level of heterosis for grain yield and total dry matter in the F2 population was half of that in F1 hybrids. The low level of inbreeding depression from the F1 to the F2 generation suggested that epistatic gene action also contributed to the expression of grain yield. Some F2 populations maintained the high yield levels of the corresponding F1 hybrids.  相似文献   

18.
19.
Summary Genotypic, phenotypic and environmental correlation coefficients were calculated for fifteen characters during two growing seasons. Correlation coefficients varie between seasons. Edible pod weight, edible pod length, edible pod width, number of seeds per plant, weight of 100 seeds, length of mature pods and number of branches per plant showed significant genotypic correlation with pod yield per plant; only number of branches per plant, edible pod length and weight of 100 seeds were phenotypically correlated with pod yield. Environmental correlation coefficients were generally low but edible pod length, final plant height and edible pod weight showed significant environmental correlation with pod yield during the two seasons.The genotypic correlation coefficients of selected eight characters with pod yield were partitioned into direct and indirect causes. In the early seasons, edible pod weight had the largest positive direct effect on pod yield with its largest indirect effect through reduction in edible pod width. Edible pod width which was highly correlated with pod yield had a negative direct effect on pod yield. In the late season, edible pod weight had the largest direct effect on pod yield, with large indirect effects through reduction in number of days to flowering and number of pods per plant. Number of days to flowering had a large direct effect on pod yield with its largest indirect effect through reduction in edible pod weight. The residual factors during the two seasons were negative. The study indicated that only number of branches per plant, edible pod length and weight of 100 seeds would be useful for indirect selection for pod yield. The path analysis indicated that edible pod weight was the most reliable and effective character to select for when high yield is the objective.  相似文献   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号