Nonparametric measures of phenotypic stability. Part 2: Applications     

Manfred Huehn 《Euphytica》1990,47(3):195-201

Summary The three nonparametric measures of phenotypic stability S_i ⁽¹⁾, S_i ⁽²⁾ and S_i ⁽³⁾ introduced and discussed in Huehn (1990) and the classical parameters: environmental variance, ecovalence, regression coefficient, and sum of squared deviations from regression were computed for winter wheat grain yield data from the official registration trials (1974, 1975 and 1976) in the Federal Republic of Germany.The similarity of the resulting stability rank orders of the genotypes which are obtained by applying different stability parameters were compared using rank correlation coefficients. The correlations between each of S_i ⁽¹⁾, S_i ⁽²⁾ and S_i ⁽³⁾ and the classical stability parameters were different in sign and very low for regression coefficient and environmental variance, but positive and medium for ecovalence and sum of squared deviations from regression (except S_i ⁽³⁾ in 1976). The differences between the correlations for the 3 years were considerable.The parameters S_i ⁽¹⁾ and S_i ⁽²⁾ were very strong intercorrelated with each other with a good agreement of the correlations for the different years. The divergent property of S_i ⁽³⁾ can be explained by its modified definition (confounding of stability and yield level).The previous results and conclusions obtained from the stability analysis of the original uncorrected data x_ij are further strengthened if one uses corrected values % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGak0Jf9crFfpeea0xh9v8qiW7rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeiwamaaDa% aaleaacaqGPbGaaeOAaaqaaiaabQcaaaGccqGH9aqpcaqGybWaaSba% aSqaaiaabMgacaqGQbaabeaakiabgkHiTiaacIcaceqGybGbaebada% WgaaWcbaGaaeyAaaqabaGccqGHsislceqGybGbaebacaqGUaGaaeOl% aiaacMcaaaa!4724!\[{\text{X}}_{{\text{ij}}}^{\text{*}} = {\text{X}}_{{\text{ij}}} - ({\text{\bar X}}_{\text{i}} - {\text{\bar X}}..)\]: The nonparametric stability measures were nearly perfectly associated (even with S_i ⁽³⁾ included) which, of course, implies no significant differences between the correlations of the different years.For the correlations between each of the S_i ⁽¹⁾, S_i ⁽²⁾ and S_i ⁽³⁾ and the classical parameters, very low values were obtained for regression coefficient and environmental variance, but relatively large values for ecovalence and sum of squared deviations from regression.The differences between the correlations for the different years are low for ecovalence and sum of squared deviations from regression with each of S_i ⁽¹⁾, S_i ⁽²⁾ and S_i ⁽³⁾, but these differences are large for regression coefficient and environmental variance. This transformation x_ijx_ij ^* reduced individual and global significances (stability of single genotypes and stability differences between all the tested genotypes) drastically. The significant results for the transformed data indicate a very reliable quantitative characterization of the stability of the genotypes independent from the yield level.  相似文献   

Correlations between the stability and adaptability statistics of popcorn cultivars     

Carlos Alberto Scapim  Cleso Antônio Patto Pacheco  Antônio Teixeira  do Amaral Júnior  Rafael Augusto Vieira  Ronald José Barth Pinto  Thiago Vincenzi Conrado 《Euphytica》2010,174(2):209-218

In plant breeding, correlations between the statistics of stability and adaptability of popcorn cultivars are not yet well understood. Therefore, the objectives of the present experiment was to investigate the correlations between s_di² \sigma_{\rm di}^{2} and b_i \beta_{\rm i} from Eberhart and Russell, ω_i from Wricke, \textS_\texti⁽¹⁾ {\text{S}}_{\text{i}}^{(1)} , \textS_\texti⁽²⁾ {\text{S}}_{\text{i}}^{(2)} and \textS_\texti⁽³⁾ {\text{S}}_{\text{i}}^{(3)} from Huehn, P_i from Lin and Binns and the rank-sum from Kang, and indicate the most reliable method for selecting popcorn cultivars. These statistics were estimated by data of crop yield from 19 Brazilian genotypes under 21 environments and popping expansion under 16 environments. The ω_i, \textS_\texti⁽¹⁾ {\text{S}}_{\text{i}}^{(1)} , \textS_\texti⁽²⁾ {\text{S}}_{\text{i}}^{(2)} , \textS_\texti⁽³⁾ {\text{S}}_{\text{i}}^{(3)} and s_di² \sigma_{\rm di}^{2} were positively and significantly correlated indicating that just one in these five statistics is sufficient for selecting stable genotypes although they were not correlated with the means of crop yield and popping expansion. The b_i \beta_{\rm i} was negatively and significantly correlated with P_i for crop yield indicating that the most adaptable genotypes tend to have the lowest estimates of P_i. Although P_i was not correlated with ω_i, \textS_\texti⁽¹⁾ {\text{S}}_{\text{i}}^{(1)} , \textS_\texti⁽²⁾ {\text{S}}_{\text{i}}^{(2)} , \textS_\texti⁽³⁾ {\text{S}}_{\text{i}}^{(3)} , or s_di² \sigma_{\rm di}^{2} statistics, it displayed positive correlation with the Index 1 (crop yield and popping expansion +  \textS_\texti⁽¹⁾ {\text{S}}_{\text{i}}^{(1)} rank) and Index 2 (crop yield and popping expansion + W_i) indicating that superior popcorn genotypes are also stable. Finally, both P_i and the rank-sum are useful statistics in breeding programmes where crop yield, popping expansion and stability are essential traits for selecting genotypes.  相似文献   

Yield stability in common bean (Phaseolus vulgaris L.) genotypes     

Frew Mekbib 《Euphytica》2003,130(2):147-153

An experiment was undertaken to determine the stability of seed yield in 21 common bean genotypes representing three growth habits. Seven genotypes in each growth habit (determinate bush, indeterminate bush and indeterminate prostrate) were evaluated in replicated trials at three locations for three years under rain fed conditions in Ethiopia. A combined analysis of variance, stability statistics and rank correlations among stability statistics and yield-stability statistic were determined. The genotypes differed significantly for seed yield and genotype × environment (year by location) interaction (GE). The different stability statistics namely Type1, Type 2 and Type 3 measured the different aspects of stability. This was substantiated by rank correlation coefficient. There were strong rank correlations among S_i ²d, W_i ²,σ_i ² and S_i ², where as there was weak correlation between b_iand R_i ², S_i ²d, W_i ², σ_i ² and S_i ². R² was significantly and negatively correlated with W_i ², σ_i ² and S_i ². σ_i ² is significantly correlated with W_i ².Yield is significantly correlated with b_i and R_i ².None of the statistics per se was useful for selecting high yielding and stable genotypes except the YS(yield-stability statistic). Most of the high yielding genotypes were relatively stable. Of the 21 genotypes, only 11genotypes were selected for their high yielding and stable performance. Genotypes with growth habit III and I (in determinate prostrate and determinate bush) were generally more stable than in determinate bush. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Rank correlation among parametric and nonparametric measures of phenotypic stability     

Hans-Peter Piepho  Savino Lotito 《Euphytica》1992,64(3):221-225

Summary There is an increasing number of stability parameters for genotypes grown in different environments. It is therefore useful to study the statistical relations between these parameters. One approach is the calculation of rank correlations between different stability parameters in empirical data sets. In the data analysed there are high rank correlations between ecovalence W_i, deviation mean square s² _di, the nonparametric measures S_i ⁽¹⁾, S_i ⁽²⁾, and two new measures R_i and L_i as well as between environmental variance S² _xi and regression coefficient b_i. The results suggest that S_i ⁽¹⁾, S_i ⁽²⁾, L_i, and R_i can be used as alternatives to W_i and the stability variance ² _i. This may be worthwhile, if certain statistical assumptions do not hold, particularly if significance testing is needed.  相似文献   

Effect of recombination in the maize breeding population with exotic germplasm on the yield stability     

Tomislav Živanović  Gordana Branković  Miroslav Zorić  Gordana Šurlan Momirović  Snežana Janković  Sanja Vasiljević  Jovan Pavlov 《Euphytica》2012,185(3):407-417

A little knowledge exists about the probability that recombination in the parental maize populations will enhance the chances to select more stable genotypes. The synthetic parent maize population ((1601/5 × ZPL913)F₂ = R₀) with 25% of exotic germplasm was used to assess: (i) genotype × environment interaction and estimate stability of genotypes using nonparametric statistics; (ii) the effect of three (R₃) and five (R₅) gene recombination cycles on yield stability of genotypes; (iii) relationship among different nonparametric stability measures. The increase of mean grain yield was significant (P < 0.01) in the R₃ and R₅ in comparison to the R₀, while it was not significant between R₃ and R₅. Analysis of variance showed significant (P < 0.01) effects of environments, families per set, environment × set interaction, family × environment interaction per set on grain yield. The non-significant noncrossover and significant crossover (P < 0.01) G × (E) interactions were found according to Bredenkamp procedures and van der Laan-de Kroon test, respectively. The significant (P < 0.01) differences in stability were observed between R₀-set 3 and R₅-set 3 determined by S_i⁽³⁾ S_{i}^{(3)} , R₃-set 1 and R₅-set 1 determined by S_i⁽³⁾ S_{i}^{(3)} (P < 0.05), and R₀-set 3 and R₅-set 3 determined by S_i⁽⁶⁾ S_{i}^{(6)} (P < 0.05). The significant parameters were those which take into account yield and stability so the differences could be due to differences in yield rather than stability. Findings can help breeders to assume the most optimum number of supplementary gene recombination to achieve satisfactory yield mean and yield stability of maize genotypes originating from breeding populations.  相似文献   

Repeatability of different stability parameters for grain yield in chickpea   总被引：1，自引：0，他引：1  

S. Kumar    O. Singh    H. A. Van  Rheenen  K. V. S. Rao 《Plant Breeding》1998,117(2):143-146

The presence of genotype × environment (GE) interactions in plant breeding experiments has led to the development of several stability parameters in the past few decades. The present study investigated the repeatability of these parameters for 16 chickpea (Cicer arietinum L.) genotypes by correlating their estimates obtained from extreme subsets of environments within a year and also over years. Based on the estimates of response and stability parameters within each trial, the ranking of genotypes in the low-yielding subset differed from that in the high-yielding subset. This indicates poor repeatability for response and stability parameters over the extreme environmental subsets. The estimates of mean yield and stability parameters represented by ecovalence, W²_i, were consistent over years, whereas those of response parameters (b_i, and S²_i) showed poor repeatability. Our results suggest that single-year results for yield and stability can be used effectively for selecting cultivars with stable grain yield if tested in a wider range of environments.  相似文献   

Genotype × environment interactions for tea yields   总被引：1，自引：0，他引：1  

Francis Wachira  Wilson Ng'etich  Joseph Omolo  George Mamati 《Euphytica》2002,127(2):289-297

Several methods were used to evaluate phenotypic stability in 20 tea (Camellia sinensis) genotypes, many of which are cultivated widely in East Africa. The genotypes were evaluated for annual yields at two sites over a six year period. Data obtained were used to compare methods of analysis of G × E interactions and yield stability in tea. A standard multi-factor analysis of variance test revealed that all first order interactions (genotypes × sites; genotypes × years; sites × years) as well as second order interactions (sites × genotype × years) were significant. Regression analysis was used to assess genotype response to environments. Regression coefficients (b_i) obtained ranged from 0.78 to 1.25. Deviations from regression (S²d) were significant (p < 0.05) from 0.0 for all the test genotypes. Analysis for sensitivity to environment change (SE² _i) revealed that the test genotypes differed in their level of sensitivity. The hierarchical cluster analysis method was used to assemble the test genotypes into groups with similar regression coefficients (b_i) and mean yield, which proved useful for the identification of high yielding genotypes for breeding purposes as well as for commercial exploitation. Rank correlation between yield and some stability parameters were significant. Mean yield was significantly correlated to b_i (r = 0.80^***) and SE² _i(0.74^***) which is an indication that selection for increased yield in tea would change yield stability by increasing b_i and SE² _i leading to development of genotypes that are specifically adapted to environments with optimal growing conditions. Genotypes differed in response to years and sites. As stand age increased, genotype yields generally increased though annual yield fluctuations were more pronounced in some genotypes than others. This response was not consistent across the sites for all genotypes indicating the need to test clones at multiple sites over longer periods of time. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Evaluation of soybean cultivars using parametric and nonparametric stability estimates   总被引：1，自引：0，他引：1  

G. L. Yue    K. L. Roozeboom    W. T. Schapaugh  Jr.  G. H. Liang 《Plant Breeding》1997,116(3):271-275

High and stable yield is a very desirable attribute of soybean (Glycine max (L.) Merr.) cultivars. Stable yield of a cultivar means that its rank relative to other cultivars remains unchanged in a given set of environments. To characterize 12 soybean cultivars chosen from performance trials, data were obtained from 10 environments (five locations in 2 years). Six stability parameters from four statistical models were derived for each cultivar. Regression coefficients were significantly and positively correlated only with coefficients of variation; they are useful in characterizing whether cultivars responded well in favourable or poor environments. Nassar and Huhn's nonparametric measures, S_i⁽¹⁾ and S_i⁽²⁾, were significantly and positively correlated with Eberhart and Russell's s_di² and Wricke's ecovalence (W_i). The stability measures are useful in characterizing cultivars by showing their relative performance in various environments. Results revealed that high-yielding cultivars also can be stable cultivars. Correlations between stability parameters obtained from individual years over the same set of locations and cultivars were very low and nonsignificant, suggesting that single-year data are not reliable as basis for selection. To provide an additional guide for selection, Kang's rank-sum approach was applied, in which both yield (in rank) and measured nonparametric stability (in rank) were considered. In general, selection for yield only would sacrifice stability to some degree, and selection for stability only would sacrifice a certain amount of yield. The rank-sum approach reconciles the two and appeared to provide a useful means to characterize soybean cultivars.  相似文献   

Stability of performance in lentil (Lens culinaris Medik) genotypes in Iran     

Mehdi Mohebodini  Hamid Dehghani  Sayyed Hossain Sabaghpour 《Euphytica》2006,149(3):343-352

The development of genotypes, which can be adapted to a wide range of diversified environment, is the ultimate goal of plant breeders in a crop improvement program. In this study, several stability methods were used to evaluate the genotype by environment interaction (GE) in 11 lentil (Lens culinaris Medik) genotypes. The genotypes were evaluated for grain yield at 4 different locations for 3 years in semi arid areas of Iran. The testing locations have different climatic and edaphic conditions providing the conditions necessary for the assessment of stability. A combined analysis of variance, stability statistics, rank correlations among stability statistics and yield stability statistic were determined. Significant differences were detected between genotypes and their GE interactions. Different univariate stability parameters were used to determine stability of the studied genotypes. The level of association among the parameters was assessed using Spearman's rank correlation. The different stability statistics which measured the different aspects of stability was substantiated by rank correlation coefficient. Rank-correlation coefficients between yield and some stability parameters were highly significant. Genotypes mean yield (Mean) was significantly correlated to the Lin and Binns stability parameter PI (r = 0.93^{* *}í) and desirability index Di (r = 0.89^{* *}í). A principal component analysis based on rank correlation matrix was performed for grouping the different stability parameters studied. In conclusion, based on most stability parameters, the genotypes G2, G5 and G9 were found to be the most stable. Results from rank correlation and principal component analysis showed that the stability variance (σ_i ²) was strongly correlated with Wricke's ecovalance, stability parameters of Plaisted and Peterson, and Plaisted.  相似文献   

Evaluation of Genotype × Environment Interactions in Chinese Spring Wheat by the AMMI Model, Correlation and Path Analysis     

W. Li  Z.-H. Yan  Y.-M. Wei  X.-J. Lan  Y.-L. Zheng 《Journal of Agronomy and Crop Science》2006,192(3):221-227

An understanding of the characteristics of crop varieties and advanced lines could help improve their cultivation and to further enhance their potential. The objectives of this study were to estimate the genotype (G), environment (E) and genotype × environment (GE) interactions on the grain yield of Chinese spring wheat genotypes in 2000 and 2001 by the additive main effects and multiplicative interaction (AMMI) model, and to evaluate the relationships between yield and its components by correlation and path analysis. Grain yield varied from 3.9 to 5.2 t ha^?1, among which SW8188 had the highest yield performance, followed by 58769‐6 and Chuannong 16. Three interaction principal components (IPC) accounted for a total of 79.99 % and 72.96 % of the interactions with 41.05 % and 52.08 % for the corresponding degrees of freedom in 2000 and 2001, respectively. When IPC3 was significant, the stability coefficient D_i was more useful in the evaluation of the stability of each genotype. The estimates of D_i in the 2 years indicated that the D_i values varied between genotypes and years. The D_i values ranged from 1.804 to 14.665 and 2.497 to 12.481 in 2000 and 2001 respectively. The suitable locations (environments) for all genotypes were characterized. These results would be useful for improving the Chinese spring wheat cultivation and improvement.  相似文献   

Genotype × environment interactions and simultaneous selection for high oil yield and stability in rainfed warm areas rapeseed (<Emphasis Type="Italic">Brassica napus</Emphasis> L.) from Iran     

Mehdi Jamshid Moghaddam  Sayyed Saeid Pourdad 《Euphytica》2011,180(3):321-335

Partitioning of the genotypes by environment interaction (GEI) is important in order to determine the nature of the GEI. The objectives of this study were to assess the presence and nature of GEI for nine agronomic traits of rapeseed cultivars, and to identify cultivars with favorable levels of stable oil production. Nine rapeseed cultivars, including seven open pollinated and two hybrids, Hyola308 and Hyola401, were grown in ten environments under rain-fed warm areas of Iran. The GEI was significant for all traits and was partitioned into components representing heterogeneity due to environmental index and the remainder of the GEI. Among the all traits with a highly significant heterogeneity, the largest amount of heterogeneity removed from the GEI was for seeds per pod and seed weight. We found GEIs for both oil content and seed yield were largely influenced by differences in correlations among pairs of cultivars (86.8 and 71.4% of the GEI sum of squares, respectively), suggesting that crossover GEIs (i.e., change in genotype rankings among environments) are present. The mean correlation of each cultivar with all other cultivars ([`(r)]<sub>ii<sup>￠</sup></sub> \bar{r}_{{ii^{\prime}}} ) ranged from 0.53 to 0.83 for oil content and 0.86 to 0.96 for seed yield. A comparison was done of the significance of Sh-σ<sub>i</sub><sup>2</sup> (stability variance derived from total GEI) and Sh-S<sub>i</sub><sup>2</sup> (adjusted stability variance derived from residual GEI) assignable to each genotype for oil content and seed and oil yield. Based on Sh-σ<sub>i</sub><sup>2</sup>, three cultivars were unstable for oil content, whereas six cultivars were unstable for seed and oil yield. The removal of heterogeneity revealed that one unstable cultivar for oil content and three unstable cultivars for oil yield were judged to be stable. All cultivars with [`(r)]_ii^￠ \bar{r}_{{ii^{\prime } }}  ≤ 0.63 were labeled unstable for oil content, whereas all with [`(r)]<sub>ii<sup>￠</sup></sub> \bar{r}_{{ii^{\prime } }}  ≤ 0.94 were considered unstable for seed yield. The relationships between [`(r)]_ii^￠ \bar{r}_{{ii^{\prime } }} and Sh-σ_i² were significant (P < 0.01) for oil content and seed yield. The results of rank correlation coefficients showed significant positive correlations of Yield-Stability statistic (YS_i) with oil content and oil yield. Cultivars such as Option500 and Hyola401 were identified as having stable, high levels to seed yield and oil content.  相似文献   

Interpreting genotype × environment interactions for durum wheat grain yields using nonparametric methods     

Reza Mohammadi  Abdolvahab Abdulahi  Reza Haghparast  Mohammad Armion 《Euphytica》2007,157(1-2):239-251

The objective of this study was to compare nonparametric stability procedures and apply different nonparametric tests for genotype × environment (G × E) interactions on grain yields of 15 durum wheat genotypes selected from Iran/ICARDA joint project grown in 12 environments during 2004–2006 in Iran. Results of nonparametric tests of G × E interaction and a combined ANOVA across environments indicated the presence of both crossover and noncrossover interactions, and genotypes varied significantly for grain yield. In this study, high values of TOP (proportion of environments in which a genotype ranked in the top third) and low values of sum of ranks of mean grain yield and Shukla’s stability variance (rank-sum) were associated with high mean yield. The other nonparametric stability methods were not positively correlated with mean yield but they characterized a static concept of stability. The results of correlation analysis indicated that only TOP and rank-sum methods would be useful for simultaneous selection for high yield and stability. These two methods identified lines Mrb3/Mna-1, Syrian-4 and Mna-1/Rfm-7 as genotypes with dynamic stability and wide adaptation. According to static stability parameters, the genotypes 12A-Mar8081 and 19A-Mar8081 with lowest grain yield were selected as genotypes with the highest stability.  相似文献   

Performance stability of maize genotypes across diverse hill environments in Nepal   总被引：1，自引：0，他引：1  

D. Sharma  R. C. Sharma  R. Dhakal  N. B. Dhami  D. B. Gurung  R. B. Katuwal  K. B. Koirala  R. C. Prasad  S. N. Sah  S. R. Upadhyay  T. P. Tiwari  G. Ortiz-Ferrara 《Euphytica》2008,164(3):689-698

The national maize improvement program in Nepal regularly receives elite maize (Zea mays L.) genotypes from CIMMYT and other countries and tests them for their performance stability in highly diverse environments. Studies were conducted on research stations and farmers’ fields at five sites in three years to determine performance stability of exotic maize genotypes. Replicated on-station and on-farm studies were conducted using 25 and 10 genotypes, respectively, including a local check and an improved check (Manakamana-3), in 2004–2006. We analyzed grain yield, days to flowering, plant and ear height, plant population, husk cover, and plant and ear aspect. Stability and genotype superiority for grain yield was determined using genotype and genotype × environment (GGE) biplot analysis that compares among a set of genotypes with a reference ‘ideal’ genotype, which has the highest average value of all genotypes and is absolutely stable. Several genotypes produced significantly higher grain yield than the local check. Four genotypes (‘Across9942 × Across9944’, ‘Open Ended White Hill Population’, ‘Population 44C10’ and ‘ZM621’), that produced significantly higher grain yield than the improved check, also had other agronomic traits (days to flowering, plant and ear height, number of ears, resistance to leaf blight, plant and ear aspect and husk cover tightness) equal to or better than the improved check. GGE-biplot analysis showed that Across9942 × Across9944 and ZM621 were the most superior genotypes in the on-station and on-farm trials, respectively. The findings from this study provide new information on the stability of the maize genotypes that are also adapted to other regions of the world. Such information could be useful for maize improvement program for the highlands in Nepal and other similar environments.  相似文献   

Electrofusion of Protoplasts and Heterokaryon Survival in the Genus Medicago     

P. D. Walton  D. C. W. Brown 《Plant Breeding》1988,101(2):137-142

The objective of this study- was to evaluate whether different statistical measures of phenotypic stability vary in their repeatability. Eight multi year and multi location variety tests of wheat, barley and oat were analysed separately for each year. Single year data of yield, of response parameters: environmental variance (S²₃ and coefficient of regression (b), and of stability parameters: deviation mean squares (S²₃), coefficient of determination (r²), ecovalence (W), and the nor, parametric measure variance of ranks (S_i4), were correlated with multi year, multi location results. Repeatability of single year results was highest for yield, where rank correlation coefficients amounted to about 0.80. s²_x and b showed medium values of nearly 0.55 The stability parameters s²_d, r², W and S_i4 did not differ in their repeatability. Respective correlation coefficients possessed values of approximately 0.40 and were very variable from experiment to experiment. Reliability of single year results was especially low for experiments with high varieties × years interactions. Single year results of the examined variety tests could not serve as a basis to quantify phenotypic stability even if more than ten locations were involved.  相似文献   

Evaluation of foliage yield and leaf quality traits in Chenopodium spp. in multiyear trials     

Atul Bhargava  Sudhir Shukla  Deepak Ohri 《Euphytica》2007,153(1-2):199-213

Stability of foliage yield and its quality components has not been investigated in vegetable chenopods due to their underutilized status. The objectives of the present study were to assess genotype-environment interactions (GEI), determine stability of yield and quality components and to compare different parametric and non-parametric stability parameters. The present study reports for the first time the effect of genotype and environment on foliage yield and three leaf quality traits viz. carotenoid, ascorbic acid and protein content in different species of Chenopodium. Twenty accessions comprising four species were tested in a randomized block design with three replications across four environments. For all the four traits the largest sum of squares was accounted for by the genotypes, followed by GEI and environments. Highest foliage yield of 16.02 q/ha was obtained from C. album PRC 9804, while the lowest was from C. album CHEN 63/80 (4.01 q/ha). Many indigenous accessions of C. album (PRC 9801, IC 107299, ‘Chandigarh’, ‘local’ and ‘NEFA’) were unstable both for foliage yield and most of the quality traits. Most of the exotic accessions of C. giganteum were both stable and high yielding, thus, reflecting the potential of these accessions for future breeding programs/variety release.  相似文献   

Stability Analysis of Yield in Maize,Wheat and Sorghum and its Implications in Breeding Programs*     

Guilan Yue  S. K. Perng  T. L. Walter  C. E. Wassom  G. H. Liang 《Plant Breeding》1990,104(1):72-80

Six stability statistics: (b_i, s²_di, , , and ) were estimated for maize, wheat and sorghum in different environments by using three statistical models. The significant linear portion of genotype × environment interaction for maize indicates different hybrids responded differently to environments, whereas the non-significant genotype × environment interaction (linear) were found for wheat and sorghum suggest that all genotypes responded similarly as the environments change. However, the highly significant pooled deviations (deviation from regression) for all three crops make yield predictions from the model less reliable. When regression coefficients (b_i) were non-significant, s²_di, became an important statistic in estimating stability. It appears that the regression coefficient, b_i, was best used to estimate genotypic adaptability, whereas s²_di, for stability. Maize and sorghum had negative correlations between the mean yield and stability statistics, s²_di, , and , suggesting that high yield and stability are not mutually exclusive in the range of environments used in this study; however, such correlations did not occur in wheat. Thus, maize and sorghum hybrids with high yield potential and high stability could be identified and selected. Correlations between mean yield and b_i, or , were positive and significant for maize and sorghum but were non-significant for wheat, indicating that such relationships may be species specific. Under a given set of testing environments, the stability ranking associated with each maize hybrid is correlated to and depends on other hybrids included in the analysis.  相似文献   

Sequence of the S 9-RNase cDNA and PCR-RFLP system for discriminating S 1- to S 9-allele in Japanese pear     

Takeshi Takasaki  Kazuma Okada  Carlos Castillo  Yuki Moriya  Toshihiro Saito  Yutaka Sawamura  Naoko Norioka  Shigemi Norioka  Tetsu Nakanishi 《Euphytica》2004,135(2):157-167

A new S ₉-allele was discovered in 6 Japanese pear cultivars, ‘Shinkou’, ‘Shinsei’, ‘Niitaka’, ‘Amanogawa’, ‘Nangetsu’ and ‘Nansui’. cDNA encoding S ₉-RNase, a stylar product of S ₉-allele, was cloned from pistils of ‘Shinkou’ and ‘Shinsei’ by 3' and 5' RACE. The S ₉-RNase gene had an open reading frame of 684 nucleotides encoding 228 amino acid residues. S ₉-RNase had a hypervariable (HV) region different from S ₁- to S ₈-RNase and shared higher similarity (95.2%) with apple S ₃-RNase than with 8 Japanese pear S-RNases (from 61.0% to 70.7%). Genomic PCR with primers ‘FTQQYQ’ and ‘anti-(I/T) IWPNV’ provided S ₁- to S ₉-amplicon (product), but could not discriminate the S ₂ from the S ₉ of ca. 1.3 kb. The S ₂ and S ₉ were distinguished by digestion with AflII and BstBI, respectively. The digestion with nine S-allele-specific restriction endonucleases, SfcI, AflII, PpuMI, NdeI,AlwNI, HincII, AccII, NruI and BstBI, distinguished S ₁ to S ₉, establishing that this PCR-RFLP system is useful for S-genotype assignments in Japanese pear harboring S ₁- to S ₉-allele. ‘Shinkou’, ‘Shinsei’, ‘Nangetsu’ and ‘Nansui’ assigned as S ₄ S ₉ were determined to be cross incompatible. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Non-parametric measures of phenotypic stability in chickpea genotypes (<Emphasis Type="Italic">Cicer arietinum</Emphasis> L.)     

Asghar Ebadi Segherloo  Sayyed Hossain Sabaghpour  Hamid Dehghani  Morteza Kamrani 《Euphytica》2008,162(2):221-229

Multi-environment trials (MET) play an important role in selecting the best cultivars and/or agronomic practices to be used in future years at different locations by assessing a cultivar's stability across environments before its commercial release. Objective of this study is to identify chickpea (Cicer arietinum L.) genotypes that have high yield and stable performance across different locations. The genotypes were developed by various breeders at different research institutes/stations of Iran and the International Center for Agricultural Research in Dray Areas (ICARDA), Syria. Several statistical methods were used to evaluate phenotypic stability of these test chickpea genotypes. The 17 genotypes were tested at six different research stations for two years in Iran. Three non-parametric statistical test of significance for genotype × environment (GE) interaction and ten nonparametric measures of stability analyses were used to identify stable genotypes across the 16 environments. The non-parametric measures (Kubinger, Hildebrand and Kroon/Van der) for G × E interaction were highly significant (P < 0.01), suggesting differential responses of the genotypes to the test environments. Based on high values of nonparametric superiority measure (Fox et al. 1990) and low values of Kang's (1988) rank-sum stability parameters, Flip 94-123C was identified as the most stable genotype. These non parametric parameters were observed to be associated with high mean yield. However, the other nonparametric methods were not positively correlated with mean yield and were therefore not used in classifying the genotypes. Simple correlation coefficients using Spearman’s rank correlation, calculated using ranks was used to measure the relationship between the stability parameters. To understand the nature of relationships among the nonparametric methods, a hierarchical cluster analysis based on non weighted values of genotypes, was performed. The 10 stability parameters fell into three groups.  相似文献   

Molecular and phenotypic characterization of the <Emphasis Type="Italic">S</Emphasis>-locus and determination of flowering time in new ‘Marcona’ and ‘Desmayo Largueta’-type almond (<Emphasis Type="Italic">Prunus dulcis</Emphasis>) selections     

Pedro J. Martínez-García  Fernando Mañas  Prudencio López  Federico Dicenta  Encarnación Ortega 《Euphytica》2011,177(1):67-78

‘Marcona’ and ‘Desmayo Largueta’ are the most widely cultivated almonds in Spain, representing around 27% of the total production and 34% of the entire almond growing surface. The excellent quality of their kernels makes them highly appreciated and demanded worldwide. However, due to their self-incompatibility, they should be grown along with cross-compatible cultivars, whose lower kernel quality often reduces the economic benefits of the plantation. In addition, although they are cross-compatible, are not good candidates to share the orchard since ‘Desmayo Largueta’ usually flowers earlier than ‘Marcona’. Therefore, to optimize orchard yield, genotypes with overlapping flowering times, cross-compatible with these cultivars and of similar fruit and ripening characteristics are desirable. In order to find suitable pollinators of these cultivars, five ‘Marcona’ and four ‘Desmayo Largueta’-type selections from “Instituto Técnico Agronómico Provincial (ITAP) de Albacete” (Spain) were characterized for flowering time and for self and cross-incompatibility. The results obtained showed that the nine ITAP selections were self-incompatible, and that three and one were promising candidates as pollinators of ‘Marcona’ and ‘Desmayo Largueta’, respectively. The S-haplotypes of two ITAP selections were characterized by cloning and sequencing their pistil S (S-RNase) and pollen S (SFB) genes. The results also showed that S _f RNase does not have a mutated histidine in C2 region, and detected differences with other previously published sequences for S ₂₃ RNase and SFB ₂₃ allele. Moreover, the sequence for almond SFB ₂₇ allele is reported here for the first time.  相似文献   

Heritability estimates of spot blotch resistance and its association with other traits in spring wheat crosses     

Ram C. Sharma  Bhairaja Pandey-Chhetri  Etienne Duveiller 《Euphytica》2006,147(3):317-327

Summary Spot blotch caused by Cochliobolus sativusis considered a major disease problem of wheat(Triticum aestivumL.) in the warm areas of South Asia. This study estimated heritability (h ²) of resistance to spot blotch and its correlation with days to heading DH) and maturity (DM), one-hundred-kernel weight (HKW), and plant height (PHT) in 14 crosses involving four resistant (‘Attila’, ‘Chirya 7’, ‘G 162’, and ‘SW89.5422’) and two susceptible (‘Sonalika’ and ‘HD2329’) wheat genotypes. Data were recorded on F₅and F₆lines in fields under natural epidemics of spot blotch in 2003 and 2004, respectively. Heritability was estimated for area under disease progress curve (AUDPC), AUDPC/day, and the highest disease score (HDS) using offspring-parent regression (h _op ²) and realized heritability (h ² _R) procedures. Heritability estimates were low to high in terms of AUDPC (0.21 < h _op ²< 0.64; 0.32 < h _R ²< 0.70), AUDPC/day (0.40 < h _op ²< 0.96; 0.42 < h _R ²< 0.99), and HDS (0.29 < h _op ²< 0.92; 0.32 < h _R ²< 0.95). The h ²estimates for AUDPC/day were higher than for AUDPC and HDS. Estimates of h _R ²were by and large higher than h _op ²in the same cross. A weak negative or nonsignificant correlation of spot blotch score with HKW, DH, DM, and PHT indicated that independent selection for resistance and these agronomic traits is possible.  相似文献