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Dimitrios Baxevanos Christos Goulas Stergios Tzortzios Athanasios Mavromatis 《Euphytica》2008,161(3):371-382
Multi-environment trial data are required, to obtain variety stability performance parameters as selection tools for effective
cultivar evaluation. The interrelationship among seven stability parameters and their association with mean yield, along with
the repeatability of these parameters across consecutive years was the objective of this study. Cottonseed yield data of 31
cotton cultivars, proprietary of Delta and Pine Land Co and other companies, evaluated in 20 locations over the 1999–2005 year
period in Greece, Spain and Turkey were used for combined analysis of variance in four datasets. Across locations in a single
evaluation year (dataset A), across locations in each of two single consecutive evaluation year (dataset B), across locations
and two consecutive years (dataset C) and across locations and three consecutive years (dataset D). For each dataset, cultivar
phenotypic variance was appropriately partitioned in its components and the h2 and component estimated. Furthermore, following the appropriate stability analysis
and AMMI1 along with the GGE Biplot distance (GGED) and instability (GGEIN) parameters were obtained. The interrelationship
among the parameters and their association with mean yield based on Spearman rank correlation was studied in each of the seven
single evaluation years (dataset A). Rank correlation coefficients were also used as estimates of the repeatability of these
stability parameters across consecutive year combinations (dataset B, C and D). The parameters GGED and YSi were consistently highly correlated with each other and mean yield in five out of seven single evaluation years. The data
provided evidence that single year evaluation across locations might be sufficient to reliably rank cotton cultivars, based
on mean yield along with GGED and YSi. Combined analysis across two consecutive years (dataset C) was more effective as compared to single year evaluation. GGED
was relatively more repeatable than YSi and mean yield in single (dataset B) and 2-year comparisons (dataset C). Although GGED is an index depended and proportional
to yield, provides a superior way to integrate mean performance and stability into a single measure, which can be assessed
visually on biplots. Regarding the other stability parameters, the results were contradicting and of low repeatability across
single years and two consecutive years. Cultivar evaluation combined across locations in 3 years did not improve the repeatability
of cultivar variance effects but resulted in very high repeatability of GGED, YSi and mean yield. 相似文献
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The aim of this study was to compare the effect of the horse on various performance tests calculated for free jumping parameters. Free jumping parameters were measured on the basis of video image analysis. Three groups of horses were compared: 141 stallions on the 11-month test (744 jumps), 50 stallions on the 8-month test (301 jumps) and 43 stallions on the 100-day test (221 jumps). Linear measurements of taking off and landing distances, height of limb lifting above the obstacle, height of elevation of “bascule points” and position of the head were measured. The statistical model was comparable for all tests including the random effect of the horse, fixed effects of the test, height of the obstacle and successive number of the jump. Repeatability on the 11-month test was high for taking off, landing and bascule parameters and reached values from 0.50 to 0.60. Repeatability of heights of limb lifting in the 11-month test was lower, but at the same value of about 0.3 for front and hind limbs. In the test of the same duration but for horses selected as the best ones—the repeatability of limb lifting was higher for front limbs and almost the same for hind limbs. Repeatability of the parameters that characterised the length of the jump and the bascule of the horse was higher in the test for the best horses and reached 0.82 for landing and 0.66–0.77 for bascule points. Repeatability of almost all jumping parameters reached highest values in the group of the best horses with longer training. 相似文献
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本研究采用单性状重复力模型和双性状动物模型分别对公猪精液体积、精子活力、精子密度、精子畸形率4个性状进行遗传参数估计,并对不同性状间的遗传相关进行估计。结果显示:精液体积为中等遗传力(遗传力为0.29),精子密度、精子活力和精子畸形率性状具有较低遗传力,遗传力分别为0.10、0.16、0.15;这4个性状均有中等偏高的重复力,分别为0.47、0.42、0.36、0.50。精液体积与精子密度具有较强的遗传负相关(-0.389),精液体积与精子畸形率具有较弱的遗传负相关(-0.171),精子活力与精子畸形率具有强的遗传负相关(-0.826),其余性状均无明显遗传相关。以上结果表明可以通过对精液性状进行选择来提高公猪精液品质。 相似文献
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[目的]建立测定水果罐头中苯甲酸、山梨酸和糖精钠的高效液相色谱法。[方法]通过回收率、精密度和重现性试验建立了测定水果罐头中苯甲酸、山梨酸和糖精钠的高效液相色谱法。[结果]通过紫外光谱扫描,确定230 nm作为测定波长。在0.010~0.200 g/L范围内,苯甲酸、山梨酸和糖精钠的回归方程相关系数均大于0.99,检出限分别为0.0100、.004和0.002 g/L。水果罐头中苯甲酸、山梨酸和糖精钠的添加回收率在94.0%~102.0%,变异系数在0.56%~2.15%。按样品测定方法平行测定5次,苯甲酸、山梨酸和糖精钠的峰面积相对标准偏差(RSD)分别为0.92%、0.79%和0.95%。[结论]该法测定水果罐头中的苯甲酸、山梨酸和糖精钠具有良好的准确性和精密度。 相似文献
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北美悬铃木无性系生根特性遗传变异研究 总被引：2，自引：0，他引：2
对50个从北美悬铃木优良家系中初选的无性系进行扦插生根性状研究.结果表明:无性系问的扦插成活率、扦插生根时间、生根根数、根系总长度等性状在基质盆插和圃地扦插均达到极显著差异水平.无性系扦插生根性状的重复力介于0.219 7-0.592 3之间,表明这些性状受中等程度的遗传控制.北美悬铃木扦插生根能力差异极大.发现NY36、NY44、SX1、ZJ9、SJ36、SX11、ZJ36、DY6、ZJ29、DY36、DY10、SX36、ZJ14、SJ8等生根数量多、重复力高的无性系14个. 相似文献
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作者对150只星杂288蛋鸡的生长发育和生产性能进行了测定,并估计7个性状遗传参数重复力,为蛋鸡育种提供了理论依据。 相似文献
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甘蔗的遗传相关及与环境互作的研究 总被引：1，自引：0，他引：1
估算了甘蔗(Saccharum officinarum L.)三个主要经济性状的遗传相关及其与环境互作的大小。结果表明,每英亩蔗产量与每英亩糖产量有强的基因型相关,而与每吨蔗的糖产量却没有这种关系。遗传参数的分析还表明,每英亩蔗产量具有最大的遗传进度,而每吨蔗的糖产量重复力最大。故甘蔗品种改良中,同时提高品种单位面积的蔗产量和单位蔗量的糖产量是可获得的。因子分析的结果说明,每英亩蔗产量和每吨蔗的糖产量之基因型方差都达显著水平;不同土壤类型和新植蔗及宿根蔗的互作都影响着每英亩蔗产量、每英亩糖产量和每吨蔗的糖产量的表型方差。因此,在甘蔗育种中要提高育种最后阶段的选择效率,排除环境因子的影响是很重要的。 相似文献
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幼龄楸树生长、生理和形态性状的遗传变异 总被引：2，自引：0，他引：2
通过对幼龄楸树无性系生长、生理和形态性状的遗传变异分析,探讨楸树早期选择指标,并进行楸树优良无性系的选择.结果表明:1年生楸树无性系间树高存在显著差异,地径不存在差异,而2～4年生楸树无性系间树高、胸径均存在极显著差异.2年生叶部各性状无性系间均存在极显著的差异,3年生皮孔各性状无性系间均存在极显著的差异.3年生树高、... 相似文献