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1.
线性混合模型最佳线性无偏预测(BLUP)不仅适用于数据不平衡和误差方差异质试验的分析,而且对随机效应的排序会更准确。在实际试验分析中由于真实方差参数值未知而采用估计值时,BLUP转变为所谓经验性BLUP(eBLUP)。为了探讨eBLUP在作物区域试验品种评价的效果,本文以我国2012—2014年长江流域油菜区域试验12套产量资料为例,对eBLUP在品种主效应和特定环境中效应的估计、排序及差异比较t测验等方面与方差分析综合比较。结果表明,对品种主效应,eBLUP与方差分析算术平均值仅有较小差异,品种排序在eBLUP与算术平均值法相同;对特定环境中品种效应,eBLUP与算术平均值法有较大差异,品种排序在eBLUP较算术平均值法更准确;用Kenward-Roger法估算基于eBLUP的效应差异t测验的自由度,无论对品种主效应还是对特定环境中品种效应,eBLUP和方差分析有着相近的显著性(α=0.05)测验效果。 相似文献
2.
为了筛选适宜昌南地区生态环境的马铃薯品种,江西现代农业科研协同创新专项“薯类作物新品种新技术研究集成与示范”专项课题组引进了马铃薯品种11个在江西省蚕桑茶叶研究所开展试验。2018年春进行了马铃薯品种对比试验,并开展了物候期、植株性状、块茎性状、抗病性、产量等调查。结果表明：早熟品种以‘中薯5号’为优(2403kg/667 m2),中晚熟品种以 ‘兴佳2号’为优(2365.29 kg/667 m2),彩色品种以‘华彩1号’和‘NFJ5’较好。为后续进行品种示范做了基础。2018年春进行了马铃薯品种对比试验,并开展了物候期、植株性状、块茎性状、抗病性、产量等调查。结果表明：早熟品种以中薯5号为优,中晚熟品种以兴佳2号为优,彩色品种以华彩1号和NFJ5较好。 相似文献
3.
A. Hadjichristodoulou 《Euphytica》1985,34(3):641-649
Summary In 1981/82 60 barleys varieties were grown at 18 environments (three locations, three seed rates, two soil fertility regimes) and in 1982/83 22 varieties were grown again at 21 environments (seven locations, three seed rates). Grain yield was recorded only in the second year. The estimates of variances sx
2 (untransformed data) and s2
logx (transformed data) for number of tillers and grain yield varied significantly among varieties. When untransformed data were used, high tillering varieties had a higher variance for number of tillers per unit area than low tillering varieties. When the variation was measured by CV of untransformed data or by s2
logx on transformed data a reverse relation occurred, i.e. the correlation coefficient between number of tillers and the variation of number of tillers was negative.High grain yielding varieties had a high mean number of tillers and a low variance for number of tillers per unit area when transformed data were used to compute variances. All interactions between variety, seed rate and location for grain yield were significant. The regression analysis of variety grain yield (Y) on environment mean grain yield (X) gave regression coefficients, b, ranging from 0.51 to 1.69. There was no significant correlation between regression coefficient and grain yield. The highest yielding varieties had b values around 1.0. High grain yielding varieties had low variance of yield over environments and low values for deviations from the regression when transformed data were used. However, the correlations between mean yield and variance for yield or mean yield and deviations from regression were positive when untransformed data were used.From this study it is concluded that high mean number of tillers per unit area and low variance for number of tillers could be used in selecting varieties with consistently high yield at varying environments. Techniques are proposed for application early in the breeding programme, i.e. in segregating population or in nurseries. 相似文献
4.
GGE双标图在河南省夏播花生品种区域试验中的应用 总被引：2，自引：0，他引：2
笔者研究了河南省夏播花生品种区域试验中参试品种与环境的互作关系,科学评价参试品种与试点,为品种审定及试点遴选提供理论依据。采用可直观分析农作物两向数据的GGE双标图对参试品种的高产稳产性、品种与试验点环境间的关系、各试点的代表性进行了分析。结果表明：2015年河南省夏播花生品种区域试验中理想品种为‘豫花55号’,能有效地选择高产稳产品种的试点是河南省农业科学院经济作物研究所、濮阳市农业科学院、洛阳市农林科学院。 相似文献
5.
小麦区域试验产量性状及其稳定性分析 总被引：4，自引：1，他引：3
为了评价小麦品种的丰产性和稳定性,运用作物品种区域试验非平衡资料的统计分析方法,利用2008年和2009年的江苏省淮北地区小麦区域试验资料,对各参试品种的产量性状及其稳定性进行了分析。方差分量分析结果表明,试点和年份×试点互作对产量及其构成因素的影响较大。参试小麦品种的平均产量变幅为7078.35~7798.11 kg/hm2,品种V2、V3、V13和V14的产量显著高于对照,其中品种V13的平均产量居首位,比对照品种V21增产500.97 kg/hm2,增产率为6.87%;品种V8和V18的产量较低但与对照品种的差异未达显著水平。产量的稳定性方面,品种V14对环境指数的反应较敏感,品种V4和V6的一致性表现较差,其余参试品种的稳定性表现相似。综观参试小麦品种两年的产量表现,丰产性和稳产性较好的品种有V2和V13,品种V14的产量较高但稳定性表现较差。此外,开展多年多点试验,对于客观评价小麦区试参试品种的产量性状及其稳定性是十分必要的。 相似文献
6.
D. Stelling 《Journal of Agronomy and Crop Science》1989,163(1):21-32
Standing ability is a major component of combining ability and yield stability in dried peas. In performance trials during 1986–1988 commercial varieties and new breeding lines were evaluated for standing ability at one location. Standing ability was measured by visual scores, crop height and standardized crop height (crop height in percent of plant length) at several observation dates during the generative phase. Visual scoring proved to be the most suitable method for the measurement of standing ability as far as time requirement and precision are concerned.
Considerable differences between years and varieties were found for both the course of lodging during the generative phase and the standing ability shortly before harvest. Several, at least three or four measurements of standing ability should be done during the generative phase. Also highly significant variety x year interactions were observed. Heritability values estimated for different parameters of standing ability were medium to high as compared to plant length and maturity date (high) or grain yield (low).
In general, standing ability of the semi-leafless varieties proved to be much better than standing ability of the conventional ones. However, the semi-leafless plant type was not always associated with an improved standing ability.
Problems relating to the methods of measurement of standing ability, its phenotypic expression and variability are discussed. 相似文献
Considerable differences between years and varieties were found for both the course of lodging during the generative phase and the standing ability shortly before harvest. Several, at least three or four measurements of standing ability should be done during the generative phase. Also highly significant variety x year interactions were observed. Heritability values estimated for different parameters of standing ability were medium to high as compared to plant length and maturity date (high) or grain yield (low).
In general, standing ability of the semi-leafless varieties proved to be much better than standing ability of the conventional ones. However, the semi-leafless plant type was not always associated with an improved standing ability.
Problems relating to the methods of measurement of standing ability, its phenotypic expression and variability are discussed. 相似文献
7.
M. Hühn 《Journal of Agronomy and Crop Science》1995,175(2):69-71
The actual yields from multilocation variety trials are commonly analysed as a two-way table (rows = varieties, columns = locations) of mean yields. In this paper, relationships between the recently proposed new stability parameter 'variance of relative yield' and the two stability parameters of the 'classical' joint regression approach in stability analysis, are investigated. The variance of relative yield as a measure of stability exhibits an undesirable dependence on the mean yield of the respective variety. Generalizations and improvements of some recent results and conclusions of Piepho (1994) are discussed. 相似文献
8.
Assessing the performance and the characteristics (e.g. yield, quality, disease resistance, abiotic stress tolerance) of new varieties is a key component of crop performance improvement. However, the variety testing process is presently exclusively based on experimental field approaches which inherently reduces the number and the diversity of experienced combinations of varieties × environmental conditions in regard of the multiplicity of growing conditions within the cultivation area. Our aim is to make a greater and faster use of the information issuing from these trials using crop modeling and simulation to amplify the environmental and agronomic conditions in which the new varieties are tested.In this study, we present a model-based approach to assist variety testing and implement this approach on sunflower crop, using the SUNFLO simulation model and a subset of 80 trials from a large multi-environment trial (MET) conducted each year by agricultural extension services to compare newly released sunflower hybrids. After estimating parameter values (using plant phenotyping) to account for new genetic material, we independently evaluated the model prediction capacity on the MET (relative RMSE for oil yield was 16.4%; model accuracy was 54.4%) and its capacity to rank commercial hybrids for performance level (relative RMSE was 11%; Kendall's τ = 0.41, P < 0.01). We then designed a numerical experiment by combining the previously tested genetic and new cropping conditions (2100 virtual trials) to determine the best varieties and related management in representative French production regions. Finally, we proceeded to optimize the variety-environment-management choice: growing different varieties according to cultivation areas was a better strategy than relying on the global adaptation of varieties. We suggest that this approach could find operational outcomes to recommend varieties according to environment types. Such spatial management of genetic resources could potentially improve crop performance by reducing the genotype–phenotype mismatch in farming environments. 相似文献
9.
Cereal rye (Secale cereale L.) is an important forage crop in the USA for stocker cattle (Bos sp.) production, thus making forage yield an important breeding objective for the crop. However, little information is known about the repeatability for forage yield in this crop. The objectives of this research were to: (i) estimate variance components for forage yield from long‐term variety trials, (ii) estimate the repeatability for forage yield and (iii) relate this to breeding strategies for increased forage yield in rye. Trials were conducted over 14 years where 97 USA open‐pollinated varieties (OPVs) were evaluated. Repeatability ranged from 0.57 to 0.86 when the data were analysed by year for the 3 years with significant genotype main effects. Possible explanations for the lack of significant genotype main effects are discussed. Practical implications of these findings indicate that the development of improved cultivars with greater forage yield will require improved methods of selection based on family performance rather than the current methods based primarily on single plant visual selection. 相似文献
10.
Fifteen selected okra varieties consisting of ten newly-developed lines and five established varieties were evaluated for stability of seed yields in eight different environments i.e. several monthly plantings for three consecutive years. Seed yield data were analyzed to determine the effectiveness of using different planting dates in seed yield trials of new okra varieties. The wide ranges of environmental indices (- 10.8 to 24.4) and seed yield (2.7 to 38.0 g plant -1) indicated significant variation between the environments even though the trials were conducted at the same location. A regression method of stability analysis showed that the mean differences between environments, the varieties and their interactions were highly significant. These results suggest that where limited resources prevent the use of several locations, different dates of planting for two or more years could be used to evaluate okra varieties for seed yield without losing much information on their relative ranking. 相似文献
11.
基于协方差阵结构优选的作物品种区域试验分析 总被引：1，自引：1，他引：0
论述了线性混合模型方差协方差结构与作物品种区域试验分析模型的对应关系,以我国2005-2006年东北华北玉米8组区域试验资料为例,按照线性混合模型分析原理及模型拟合信息量准则与似然比测验,对区域试验品种方差协方差的结构特性及不同方差协方差结构模型在品种效应估计与评价的差异状况进行了探讨。结果表明,在分析的所有试验中,环境间品种效应方差协方差均不符合方差分析模型假设的同质性结构,而是呈现为各种异质性结构;产量效应测验差异显著的品种对数目在方差分析模型与最佳方差协方差结构线性混合模型间的一致率平均为86%,品种产量效应排序在两种模型间也存在明显不同,品种产量效应估计的平均误差在最佳方差协方差结构线性混合模型小于在方差分析模型。 相似文献
12.
T. R. Chandrasekhar J. G. Marattukalam V. C. Mercykutty P. M. Priyadarshan 《Euphytica》2007,156(1-2):67-75
With the objective to explore the possibility of optimising selection for reducing the number of years of yield recording that could be sufficient enough to establish the lowest risk tapping-age for selecting the potential clones from field-level clone trials, long-term yield data (13–16 years) from eight clone evaluation trials were subjected to formal graphical/statistical analytical techniques. Non-linear curves were fitted to yield data and the year of start of upper asymptotic phase was worked out. Correlations were worked out between mean yield of all the years’ data and cumulative mean yield over 3–10 years of tapping. Success rate achieved in the selection of high yielding clones from the third year of tapping was worked out. The mean maximum dy/dx (first derivative of the curve) across all trials ranged from 3 to 7 years of tapping with mean maximum dy/dx at 4 years. Correlations observed from the sixth year of tapping were highly significant in most of the trials. Considering the results from all the three analytical techniques, it was concluded that six years of yield recording would be required for optimising selection of top yielding clones from large-scale clone trials. The possible use of these results is discussed in the framework of a global selection scheme with a view to shorten the breeding cycle of Hevea brasiliensis. 相似文献
13.
糖能兼用甘蔗品种（系）对不同播种密度的响应 总被引：2，自引：1，他引：1
为了解不同糖能兼用甘蔗品种（系）在不同播种密度条件下的生产性能表现,为今后进行能源甘蔗品种推广应用提供参考。对来自国内外的5个糖能兼用甘蔗品种（系）在5种不同播种密度下进行1年新植1年宿根种性比较试验。结果表明,不同播种密度水平之间的平均生物产量、蔗茎产量、蔗糖产量和总可发酵糖产量差异均不显著;B1、B8、GT26、GT97/69、GT22等品种（系）之间在生物产量、蔗茎产量、蔗糖产量、总可发酵糖产量和株高、茎径、有效茎数等产量构成因子方面的差异达到极显著水平;GT97/69、B1对播种密度反应比较敏感,其最适宜的播种量分别是每公顷12万芽和13.5万芽,其他品种反应则不敏感。甘蔗的产量主要由品种（系）的种性决定,不同品种对不同的播种密度反应不同,甘蔗新品种在推广应用之前应在不同栽培管理水平和环境条件下进行播种密度试验,确定比较合理的单位面积播种量。 相似文献
14.
Varietal seed mixtures tend to increase and stabilize crop yields, yet their application is sparse. Large-scale cultivation of variety mixtures may require a better understanding of how inter-varietal interactions and their interaction with the environment may influence the grain yield of variety mixtures relative to their component varieties. For this purpose, six variety mixtures of spring barley and 14 component varieties were grown in each of 17 trial environments. A total of 28 observed and a priori plant characteristics, including grain yield, disease severity and weed competitiveness, were derived for each component variety in each trial. The relationship between inter-varietal diversity of each characteristic and the mixing effect on grain yield was analysed. Additionally, various types of yield stability were estimated and compared among mixtures and component varieties. One mixture out-yielded all of its component varieties in almost half of the trial environments. Inter-varietal diversity in grain yield potential correlated significantly with mixing effect, as did straw length diversity when weighted with weed pressure. The grain yields of most mixtures were more stable across environments than their component varieties when accounting also for the general response to environmental productivity. Hence, most mixtures adapted slightly better to environmental productivity and were less sensitive to environmental stress than their component varieties. We conclude that the efficacy of variety mixtures may be enhanced by mixing relatively high-yielding varieties differing in responsiveness to environmental productivity. 相似文献
15.
对作物区域试验中参试品种产量统计方法问题的探讨 总被引：1，自引：1，他引：0
品种区域试验是作物品种评价、布局和推广的依据。在国家谷子品种区域试验中,由于试点间地力或管理水平不同,各试点的产量水平差别很大,往往存在一点或少数试点产量水平明显高于或低于其他试点,这些试点的产量数据在汇总时占的份额过高,导致这些试点结果对整体试验结果影响过大,甚至基本可以决定整体试验结果的情况。因而,如何使试验结果比较客观、准确地反映参试品种的实际产量水平,一直是制约区域试验工作和品种审定工作的难题。针对这一问题,作者在多年从事国家谷子品种区域试验的实践中,总结出用各承试点的理论产量代替实际产量进行汇总,即将各承试点对照的产量进行平均,然后,以这一数据为基础,依据参试品种在各承试点较对照增减产的比例,计算它们在相应试点的理论产量,将各承试点的产量调整到同一水平,剔除地力等因素对产量的影响。经验证,该方法统计的参试品种较对照增减产比例与各试点增减产比例的平均数基本一致,基本反映了参试品种的实际产量水平。取得了较好的效果,对区试资料的汇总工作具有较大参考意义。 相似文献
16.
Herbage yield trials are necessary to test if candidate varieties are well suited for organic conditions. In order to elucidate
a particular suitability for organic conditions, we run such trials in parallel under both organic and conventional conditions.
Here, we report on second and third year results of the sowings 2004 and 2005. These trials are part of a targeted breeding
programme for organic conditions. Irregular colonisation of pure grass plots with adventitious plants, in particular white
clover, was recognized as a major constraint to the quality of the results obtained under organic conditions. The coefficients
of variance in dry matter yield almost doubled when compared to conventional trials, and significant differences in annual
yield among varieties were rare. However, when herbage yield was corrected for the estimated fraction of adventitious plant
colonization at each cut, the number of instances with statistically significant differences for annual yield among varieties
increased more than fourfold. Dry matter yields under organic and conventional conditions were significantly and positively
correlated. However, analysis of variance showed a significant culture type by variety interaction for annual dry matter yield
in 12 out of 24 trials. When diploid and tetraploid varieties of the same Lolium species were tested in one common trial, only tetraploid varieties were identified as being particularly well suited for organic
conditions, while in these trials, the great majority of apparently poorly suited varieties were diploid. This suggests that
breeding tetraploid Lolium varieties is promising when aiming at a favourable response to organic agriculture. 相似文献
17.
Chickpea (Cicer arietinum L.) is normally grown as a spring-sown rainfed crop in the Mediterranean region in areas receiving more than 400 mm of rainfall annually. Because of large fluctuations in the total amount and distribution of the rainfall, the crop occasionally suffers from extreme terminal drought. Breeders face a dilemma in selecting materials for both normal moisture regimes and drought conditions because it is often difficult to conduct two parallel breeding programmes. This study examines the transferability of the selection indices (developed as a multiple regression of yield on most influential traits) from one environment to another with the objective of selecting an appropriate environment for the development of cultivars adapted to both environments. Experiments were conducted for 3 years (1989-1991) during the spring at two locations with normal moisture regime (hereafter referred to as drought-free) in Syria and Lebanon and one drought-prone location in Syria. Each year, 192-240 newly bred lines were evaluated in replicated trials for seed yield, days to flowering and maturity, plant height and 100-seed weight. Correlation analyses showed that increased seed size, early maturity and reduced plant height at the drought-prone location and early maturity at the drought-free location were of prime importance in increasing seed yield. Regression equations developed to predict seed yield showed that days to flower and maturity accounted from 67-80 % variation in seed yield at the dry location, whereas at the drought-free locations the contribution of days to maturity was smaller except in 1991 in Lebanon. The percent success in the transferability of the selection indices from the drought-free environments to the drought-prone environment was higher than that from the drought-prone environment to the drought-free environment. These results indicate that chickpea breeding material developed under drought-free environments could be useful under drought-prone conditions. Early-maturing lines selected under normal environments would also perform well under drier conditions. 相似文献
18.
黄淮海南部玉米新品种丰产性和稳产性及应用前景分析 总被引：1，自引：1，他引：0
对初步证明有应用前景的新苗头组合进行区域内多年多点鉴定试验,在丰产性、稳产性和区域适应性方面综合评价有应用前景的新杂交种。本研究于2016-2018年以黄淮南部地区种植的7个品种组合在6个试验地点产量结果进行分析,结果表明：参试品种产量的环境效应和基因型×环境互作效应均存在极显著差异。从参试地点看出苏试51417丰产性和稳产性综合评价很好；金大丰1906和苏玉41稳产性很好,丰产性较好,综合评价良好,相对具有较大的推广应用空间,适合江苏省春夏播区域种植。 相似文献
19.
Susie Guilly Thomas Dumont Audrey Thong-Chane Laurent Barau Jean-Yves Hoarau 《Euphytica》2017,213(9):213
The sugarcane variety development program on Réunion Island is dedicated to an industry that encompasses numerous different agroclimatic production zones. The objective of this study is to characterize in detail the final selection stage of this program, consisting of multienvironment trials (MET) at seven representative locations, considering the genotypic response in terms of tonnes of cane per hectare (TCH), estimable recoverable sugar (ERS), fiber content (FIB), and an economic index (EI). Data from four recent variety series tested between one and three crop years were used. Each trait revealed a significant genotype × location (GL) interaction, always higher than the genotype × crop year (GC) interaction, indicating that testing genotypes across locations is more important than testing for ratooning ability. Broad-sense heritability (H) at MET level was relatively high for FIB compared with EI, while ERS and TCH exhibited intermediate H values. Genotype main effect plus genotype × environment (GGE) biplot analysis applied to a balanced set of genotypes tested over two crop years across all environments permitted reliable visualization at a glance of (i) the level of proximity between genotypes or environments, and (ii) the performance of varieties in each environment and their stability across all of them. No redundancy between any pair of environments was found for the most important selection trait (EI). These results confirm the relevance of a selection strategy firstly oriented toward selecting sugarcane genotypes for local adaptations with the objective of enhancing the mean productivity of the whole cane industry. 相似文献
20.
Hanne ?sterg?rd Kristian Kristensen Hans O. Pinnschmidt Preben Klarskov Hansen Mogens S. Hovm?ller 《Euphytica》2008,163(3):391-408
For low-input crop production, well-characterised varieties increase the possibilities of managing diseases and weeds. This
analysis aims at developing a framework for analyzing grain yield using external varietal information about disease resistance,
weed competitiveness and yield potential and quantifying the impact of susceptibility grouping and straw length scores (as
a measure for weed competitiveness) for predicting spring barley grain yield under variable biotic stress levels. The study
comprised 52 spring barley varieties and 17 environments, i.e., combinations of location, growing system and year. Individual
varieties and their interactions with environments were analysed by factorial regression of grain yield on external variety
information combined with observed environmental disease loads and weed pressure. The external information was based on the
official Danish VCU testing. The most parsimonious models explained about 50% of the yield variation among varieties including
genotype-environment interactions. Disease resistance characteristics of varieties, weighted with disease loads of powdery
mildew, leaf rust and net blotch, respectively, had a highly significant influence on grain yield. The extend to which increased
susceptibility resulted in increased yield losses in environments with high disease loads of the respective diseases was predicted.
The effect of externally determined straw length scores, weighted with weed pressure, was weaker although significant for
weeds with creeping growth habit. Higher grain yield was thus predicted for taller plants under weed pressure. The results
are discussed in relation to the model framework, impact of the considered traits and use of information from conventional
variety testing in organic cropping systems. 相似文献