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81.
Daniel J. Tolhurst Ky L. Mathews Alison B. Smith Brian R. Cullis 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(4):279-300
Genomic selection (GS) is a statistical and breeding methodology designed to improve genetic gain. It has proven to be successful in animal breeding; however, key points of difference have not been fully considered in the transfer of GS from animal to plant breeding. In plant breeding, individuals (varieties) are typically evaluated across a number of locations in multiple years (environments) in formally designed comparative experiments, called multi‐environment trials (METs). The design structure of individual trials can be complex and needs to be modelled appropriately. Another key feature of MET data sets is the presence of variety by environment interaction (VEI), that is the differential response of varieties to a change in environment. In this paper, a single‐step factor analytic linear mixed model is developed for plant breeding MET data sets that incorporates molecular marker data, appropriately accommodates non‐genetic sources of variation within trials and models VEI. A recently developed set of selection tools, which are natural derivatives of factor analytic models, are used to facilitate GS for a motivating data set from an Australian plant breeding company. The power and versatility of these tools is demonstrated for the variety by environment and marker by environment effects. 相似文献
82.
20%毒死蜱微胶囊悬浮剂防治松墨天牛成虫药效试验 总被引:2,自引:0,他引:2
以8%氯氰菊酯(绿色威雷)微胶囊悬浮剂为对照药剂,测定了20%毒死蜱微胶囊悬浮剂对松墨天牛成虫的防治效果。野外罩笼试验结果表明,药后1 d,毒死蜱500,400,300倍和8%氯氰菊酯300倍处理的松墨天牛成虫校正死亡率分别为60.13%,60.78%,73.63%和60.73%;药后第3天,各处理校正死亡率达83.92%~89.68%,处理之间差异不显著。罩笼试验的持效期可达15 d以上。野外原木材垛上的药效试验结果显示,药后第7天,毒死蜱600,300倍和8%氯氰菊酯300倍处理的防治效果依次为64.68%,63.12%和72.92%,处理间无明显差异。研究结果表明,20%毒死蜱微胶囊悬浮剂对松墨天牛成虫的防治效果与8%氯氰菊酯微胶囊悬浮剂接近,可以作为替代药剂交替使用,以延缓靶标害虫抗药性的产生。 相似文献
83.
针对当前我国大力发展生物质能发电可再生新能源中生产环节用水状况进行了详细的分析,通过对生产运行中各个环节的水质实测数据统计,寻找到一条可以合理降低生物质能发电厂单位发电量水耗指标的串级用水技术路线。 相似文献
84.
以经防腐处理的木材作香蕉支撑和育苗大棚的大田试验;在园林建筑方面作应用试验。经过2年多的观察,初步结果表明,经防腐处理的木材未发现腐烂和虫害,经受多次台风袭击仍完好无损。防腐处理木材用于农业和园林建筑,效果良好。 相似文献
85.
86.
Changes in the Relationship Between Temperature During the Seed‐Filling Period and Soya Bean Seed Isoflavones Under Water‐Deficit Conditions 下载免费PDF全文
Isoflavones have been shown to have health‐promoting activities in humans and are particularly abundant in soya bean. This study was conducted to determine how water deficit during seed fill affects the already known relationship between temperature and, alternately, solar radiation with soya bean seed isoflavone content. Isoflavone profile was analysed from seed samples of commercial cultivars grown in 76 environments in Argentina (29–38°S). Significant explanatory multiple linear regressions were detected for total isoflavones (TI), aglycones (AGL), glucosides (GLC), malonyl glucosides (MAL) and acetyl glucosides (ACE) regarding the following: temperature during seed fill (TmR5R7) and precipitation minus potential evapotranspiration during the reproductive period (pp‐PETR1R7), as well as for the combinations of these climatic variables. Cumulative solar radiation predicted isoflavone content but was less robust than TmR5R7 and pp‐PETR1R7. To our knowledge, this is the first report of changes in the relationship between TI, as well as AGL, GLC, MAL, and ACE and TmR5R7 as a function of drought in the field. When pp‐PETR1R7 was below 70 mm (indicating drought), TI, as well as AGL, GLC, MAL, and ACE decreased linearly with rising temperatures and with increasing water deficit (decreasing values of pp‐PETR1R7), with both climatic variables exhibiting additive effects on isoflavones. Our results also suggest that water deficit (estimated by pp‐PETR1R7) would be important for modelling the relationship between temperature and soya bean seed isoflavones in rainfed crops. 相似文献
87.
88.
在研究考察事物过程中,有时需要对个体从不同方面考察分析许多指标,以判定某总体中个体间的优劣。同分等概方法是把所有的考察指标都同分等概地分数化,以总分 相似文献
89.
R. J. Vandenbelt 《Agroforestry Systems》1991,14(3):233-244
Faidherbia albida is a well-known and widespread agroforestry species of the Sudano-Sahelian zone of West Africa. Recent collection and testing
efforts have included attempts to introduce seed origins from eastern and southern Africa into the Sahel. These have generally
met with failure. Despite superior early growth, mortality is severe by the first or second year. Trials conducted at the
ICRISAT Sahelian Center in Niger have demonstrated that this is probably due to differences in rooting patterns between southern
and western Africa origins. A separation of the species into two ecotypes, i.e., upland (western Africa) and riparian (eastern,
southern and southwestern Africa) is proposed. Based on this argument, the Sudan/Ethiopia region is identified as a possible
center of origin for the species.
Submitted as ICRISAT Journal Article # JA-1107. 相似文献
90.