Contributions to the Analysis of Genotype × Environment Interactions: Theoretical Results of the Application and Comparison of Clustering Techniques for the Stratification of Field Test Sites     

M. Hühn  & B. Truberg 《Journal of Agronomy and Crop Science》2002,188(2):65-72

For an analysis of cross-classified data sets with rows = genotypes and columns = environments (locations and/or years), existing genotype × environment interactions are of major importance. Differential responses of genotypes (environments) across environments (genotypes) are expressed by these effects. To reduce the impact of these genotype × environment interaction effects, one commonly stratifies genotypes or environments by cluster analysis techniques into homogeneous groups so that interactions within groups are minimized. The present paper presents a comprehensive overview of the numerous procedures for stratification of genotypes or environments by cluster analysis which have been proposed in the literature. In these studies, two different concepts of interaction have been used: the crossover concept of interaction [different rank orders of genotypes (environments) within environments (genotypes)] or the usual statistical concept of interaction (deviations from additivity of main effects in the linear model). For a quantitative characterization of cluster techniques and for a comparison of two different clustering procedures, two parameters are introduced and discussed: measure of resemblance for two classifications and cluster size for one classification.  相似文献   

The Influence of Genotype–Environment Interaction on the Grain Yields of 10 Pigeonpea Cultivars Grown in Kenya     

J. N. Wamatu  & E. Thomas 《Journal of Agronomy and Crop Science》2002,188(1):25-33

To study the importance of the effects of genotype–environment interactions on the yield of pigeonpea ( Cajanus cajan L. Millsp.), 10 early-maturing genotypes were grown in a randomized complete block design with three replications in a total of seven environments spread over five regions of Kenya between 1987 and 1988. Results indicated the presence of a substantial genotype–environment interaction effect on grain yield. The observed significant genotype–environment interaction effect is discussed in relation to its importance in pigeonpea grain yield evaluation studies. It is noted that the best genotype in one environment is not always so in other environments. Results from regression analysis indicated that this method of analysis is appropriate for describing the response of pigeonpea genotypes grown in a number of locations. Analysis of variance showed significant additive and multiplicative genotype–environment interaction effects. Only the first interaction principal component axis (IPCA) was found to be important in describing the multiplicative interaction effects. The additive main effects and multiplicative effects (AMMI) model allowed the partitioning of interaction variance into agronomically important sources (genotype groups), and the specific genotype × environment patterns that are the basis of these sources of variance were examined.  相似文献   

日粮能量和蛋白水平对双向选择血浆极低密度脂蛋白浓度肉鸡腹脂和产肉性能的影响   总被引：1，自引：0，他引：1  

陈金文  杨山  莫棣华  文伯珍  赵河山  胡刚安 《中国兽医学报》1998,(4)

对７０８只（公母各半）５～９周龄一世代高、低极低密度脂蛋白（ＶＬＤＬ）系肉鸡进行３个代谢能水平（１３．４，１２．５，１１．６ＭＪ／ｋｇ）和３个粗蛋白水平（２２．４％，１９．４％，１６．４％）的三因子交叉的遗传－营养互作试验，以探讨肉鸡腹脂及屠体性状的遗传、营养、性别间的互作效应。结果表明：日粮对脂肪沉积的影响存在品系差异，品系与日粮代谢能互作对板油有明显影响（Ｐ＜０．０５）；日粮代谢能和粗蛋白对高ＶＬＤＬ系板油的影响大于低ＶＬＤＬ系，高ＶＬＤＬ系板油随日粮代谢能的升高而升高，而低ＶＬＤＬ系无此规律。品系与日粮代谢能互作对肌胃脂率有明显影响（Ｐ＜０．０５），日粮代谢能对低ＶＬＤＬ系肌胃脂的影响大于高ＶＬＤＬ系，而粗蛋白对高ＶＬＤＬ系肌胃脂的影响大于低ＶＬＤＬ系。品系间肌胃脂的差异在不同日粮代谢能水平下表现不一致。品系与日粮互作对产肉性状未产生明显影响。日粮代谢能与性别间的互作对腿肌率有明显影响（Ｐ＜０．０５），雌性腿肌率随代谢能水平的升高而降低。  相似文献   

兰花信息咨询系统     

彭东辉 《福建林学院学报》2004,24(2):179-181

兰花信息咨询系统分为4大模块:搜索查询模块,帮助模块,系统维护模块,浏览模块,以Windows98/XP/2000作为开发平台,采用PowerBuilder8 0为程序设计语言,运用OLE技术开发出图文并茂的的数据库,并采用面向对象程序设计思想,可视化编程技术,整个界面简洁漂亮,易于修改和操作,智能化程度高,可在实际的园林教学和生产上得到广泛应用  相似文献   

Genetic analyses of agronomic and seed quality traits of doubled haploid population in Brassica napus through microspore culture   总被引：1，自引：0，他引：1  

G. Q. Zhang  Y. He  L. Xu  G. X. Tang  W. J. Zhou 《Euphytica》2006,149(1-2):169-177

Summary The results showed that the F1 genotype from the cross (Brassica napus cv. Zheshuang 758 × cv. Z-4115) had good response to embryogenesis, and their embryo yield and rate of plant regeneration reached 69.8 embryo/bud and 46.9%, respectively. Characters from the doubled haploid (DH) populations in B. napus were analyzed and it was showed that the means of each agronomic trait were between their parents, but they were nearer to the paternal in 6 agronomic traits (plant height, branch position, number of pods in the main raceme, length of pod, number of pods/plant and number of seeds/pod). The number of genes controlling each agronomic trait was analyzed based on the DH populations. The results showed that the number of genes controlling number of pods in the main raceme was the highest (15.6), and the least number of genes was involved for stem width (only 7.9). According to estimated coefficients of skewness and kurtosis of the traits tested, gene interaction was found to be absent for stem width, plant height, length of main raceme, number of primary and secondary branches, pod density in the main raceme and seed weight/plant. Complementary interaction was also observed in five agronomic traits (number of pods in the main raceme, length of pod, number of pods/plant, number of seeds/pod and 1000-seed weight). A significantly positive correlation was observed between seed yield/plant and four agronomic traits (length of main raceme, length of pod, number of pods/plant and 1000-seed weight). The experiment also showed that the erucic acid, glucosinolate, oil and protein contents of DH populations were 34.23%, 87.09 μmol/g, 44.09% and 42.67%, respectively. The numbers of genes controlling each quality trait were 7.8, 9.7, 9.4 and 8.7, respectively. Partial correlations between the seed quality traits and the agronomic characters of DH populations were analyzed. In this experiment, the partial correlations among seed quality traits were also analyzed and it was found that the oil content had a negative correlation with the other three seed quality traits.  相似文献   

Phenotypic correlations between maize inbreds and their single cross hybrids in short season areas     

Bülent Samanci 《Euphytica》1996,89(3):291-296

Summary This study was conducted to determine the relationships among various agronomic traits in inbreds, hybrids and between inbreds and their progeny of maize in short season areas. Phenotypic correlations of each measured trait between as well as among hybrids and inbreds were not the same. The highest correlation coefficient (r=0.78) was obtained between days to anthesis and yield. The high yielding inbreds did not necessarily give rise to high yielding progeny. Given that days to anthesis plays an important role in two major traits (yield and moisture) for hybrids, an emphasis on optimum anthesis dates during inbred development could be a useful criterion for the prediction of hybrid performance in short season areas.  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   

Genotype-Environment Interactions and Stability Analysis for Herbage and Seed Yields of Forage Peas Under Rainfed Conditions   总被引：1，自引：0，他引：1  

A. M. Abd  -El Moneim  P. S. Cocks  B. Mawlawy 《Plant Breeding》1990,104(3):231-240

Twenty-five genotypes of forage peas (Pisum sativum L.) were evaluated under rainfed conditions for two years at four locations in Syria and one in Lebanon. Since local climatic variation is significant, each location in each year was treated as a separate environment, to give ten environments. Genotype-environment interactions (GXE) were analysed using linear regression techniques. There was considerable variation in herbage and seed yields within both genotypes and environments. Genotype-environment interactions were present for both herbage and seed yields; a large proportion of these interactions was accounted for by the linear regression. Although the non-linear component was also significant, its magnitude was smaller than that of the linear component. The highest and most stable herbage yields were obtained from accessions 46/61, 135/175, 3211/323, 99/103 and 88/335. The highest and most stable seed yields were produced by accessions 4/166, 2428/240, 424/242 and 88/335. Accession 88/335 from Germany, F.R. was the only genotype to combine high herbage and seed yields with wide adaptation and stability and could thus be considered the most widely adapted genotype. Other stable genotypes were identified as suitable for poor environments. Yield of the locally collected genotype, though often high, was found to be unstable. The importance of genotype-environment interactions in future breeding strategies is discussed.  相似文献   

Optimising potato breeding. II. A model for optimising single-stage and single-trait selection     

H. Vermeer 《Euphytica》1991,53(2):151-157

Summary A model for optimising single-stage and single-trait selection is presented. The model is based on the expected selection response model, extended with parameters describing the nature of the environment and with variables allowing a manipulation of selection schemes. As an example, the model is used to optimize tuber yield selection in potato breeding.Estimated parameter values have an uncertainty, which may bias the model outcome. Sensitivity analysis shows that the sensitivity to unrealistic parameter values for optimal allocation is less than the sensitivity for the selection response.  相似文献   

“Ch型”谷子显性核不育的遗传及其应用研究（Setaria italica）   总被引：2，自引：1，他引：2  

胡洪凯  石艳华  王朝斌  赵虎臣 《作物学报》1993,19(3):208-217

通过对“Ch型”谷子显性核不育的遗传研究,证实“Ch型”的不育性与“澳大利亚谷”的细胞质无关,其育性是受两对显性连锁基因Ms-和Rf-上位互作控制的。其中Ms是显性不育基因,Rf是显性上位基因,当二者共同存在时,显性上位基因能抑制显性不育基因的表达,从而使不育表现可育。这种由杂交而来,并能找到“恢复系”的显性核不  相似文献