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991.
Ammar Elakhdar Toshihiro Kumamaru Kevin P. Smith Robert S. Brueggeman Ludovic J.A. Capo-chichi Shyam Solanki 《Journal of Crop Science and Biotechnology》2017,20(3):193-204
Changes in the relative genetic performance of genotypes across environments are referred to as genotype × environment interactions (GEIs). GEIs can affect barley breeding improvement for salt tolerance because it often complicates the evaluation and selection of superior genotypes. The present study evaluated the GEIs over 60 barley genotypes for yield components and grain yield in six salinity environments in North Delta, Egypt. Data were analyzed using the additive main effects and multiplicative interaction (AMMI) and Tai’s stability parameters. GEIs effects on yield explained 20.3, 20.1, 14.6, and 33.0% of the total variation besides, the first two principal components account for 67.3, 56.3, 64.3, and 83.7% of the explained variance in the four sets, respectively. Six genotypes namely G-4, G-7, G-20, G-34, G-36, and G-39 were found to be most stable and high yielding across environments (GY >2.00 t ha-1), and located close to zero projection onto the AEC ordinate. Tai’s stability parameters demonstrated that these genotypes were more responsive to the environmental changes. The genotypes G-50 and G-53 showed perfect/static stability (α = -0.95, -0.91, respectively). In contrast, the genotype; G-36 had α = 0 and λ = 1.10, indicating parallel with the environmental effects followed by G-44. Overall, we found that GEIs for grain yield are highly significant in all sets, suggesting that responded differently across environments. This interaction may be a result of changes in genotypes’ relative performance across environments, due to their differential responses to various abiotic factors. 相似文献
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993.
Soil N mineralization is affected by microbial biomass and respiration, which are limited by available C and N. To examine
the relationship between C and N for soil microbial dynamics and N dynamics, we conducted long-term laboratory incubation
(150 days) after C and N amendment and measured changes in C and N mineralization, microbial biomass C, and dissolved C and
N throughout the incubation period. The study soil was volcanic immature soil from the southern part of Japan, which contains
lower C and N compared with other Japanese forest soils. Despite this, the area is covered by well-developed natural and plantation
forests. Carbon amendment resulted in an increase in both microbial biomass and respiration, and net N mineralization decreased,
probably due to increasing microbial immobilization. In contrast, N amendment resulted in a decrease in microbial respiration
and an increase in net N mineralization, possibly due to decreased immobilization by microbes. Amendment of both C and N simultaneously
did not affect microbial biomass and respiration, although net N mineralization was slightly increased. The results suggested
that inhibitory effect on microbial respiration by N amendment should be reduced if carbon availability is higher. Thus, soil
available C may limit microbial biomass and respiration in this volcanic immature soil. Even in immature soil where C and
N substrate is low, soil C, such as plant root exudates and materials from above- and belowground dead organisms, might help
to maintain microbial activity and N mineralization in this study site. 相似文献
994.
松口蘑的半人工及人工驯化栽培 总被引:3,自引:0,他引:3
论述了松口磨的适应性和驯化潜能, 介绍了松口蘑半人工栽培的基本方法并进行评估, 分析了应用纯培养菌种人工栽培松口蘑的难点和关键问题, 提出了松口蘑人工驯化栽培的技术路线。 相似文献
995.
本文试图通过确定高职院校专业发展阶段识别的指标体系,建立相应的模糊识别模型,客观地认识和区分高职院校已有专业所处的发展阶段,准确地掌握高职院校专业的发展现状与未来变动趋势,并为增设新专业、调整和修改老专业提供一个系统化、可操作性强的分析管理工具,减少专业设置和发展中的盲目性和随意性。 相似文献
996.
997.
网状细胞肉瘤又称网状细胞增殖症,是淋巴网状系统的一种肿瘤。本病多见于鸡,猫也曾有过报道,国内在犬还未见报道,现介绍如下。1 病史1只2岁北京狮子犬,在包皮表面有红枣大小的肿块,经手术切除后,送病理室作组织病理学和电镜检查。2 肉眼观察患犬包皮表面有红枣大小的肿块,其大小为5-5cm×2-5cm,分叶,呈桑椹状,呈粉红色鱼肉样外观。质地柔软,脆弱,与周围组织界限明显,血管很丰富,一碰即出血,见图1。图1 包皮表面的肿块(↑)3 组织病理学变化肿瘤组织由大量形态和大小各异、呈圆形、梭形或星形的淋巴样… 相似文献
998.
999.
1000.
<正>水产动物在疾病和应激时,机体会产生大量自由基。如果动物自身的抗氧化系统不能及时将自由基清除,将会对水产动物造成严重的氧化损伤。在水产饲料中添加外源抗氧化剂,可以减轻或消除自由基对水产动物的氧化损伤。随着自由基研究和水产动物营养学的 相似文献