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991.
S. Iptas 《Journal of Agronomy and Crop Science》2002,188(5):357-362
The effects of row spacing (17.5 or 35.0 cm), support plant species (barley or triticale) and the proportion of crops in mixtures (no support plant or support plant 20, 40 or 60 %, respectively) on the seed yield and yield characteristics of Hungarian vetch (Vicia pannonica Crantz) were investigated. Increasing the row spacing increased the seed yield of V. pannonica from 881.0 to 1248.0 kg ha?1. On average, in a pure stand the seed yield of V. pannonica was 1141.0 kg ha?1. In mixtures with barley and triticale, the seed yield of V. pannonica averaged 986.0 and 1143.0 kg ha?1, respectively. In single mixed stands the seed yield of V. pannonica varied between 551.0 kg ha?1 (60 % support plant barley) and 1603.0 kg ha?1 (20 % support plant triticale). The yield advantage of V. pannonica in this triticale mixture was 40 % compared to the V. pannonica pure stand. With respect to the total yield in the mixture with 20 % triticale (1902.0 kg ha?1) the yield advantage over the V. pannonica pure stand was as high as 65.1 %. In the mixed stands the number of seeds per pod and the thousand‐seed weight of V. pannonica were higher than in V. pannonica pure stands. 相似文献
992.
993.
pMGA多基因家族主要编码一类黏附素/血凝素蛋白,存在于鸡败血支原体的细胞表面,其主要功能是促进支原体黏附到宿主细胞上。近年来的相关研究发现,编码pMGA的基因数量从32-70不等,主要转录水平上通过(GAA)n 基序的数量改变引发pMGA基因的选择性转录,造成pMGA的抗原发生变异,从而干扰宿主正常免疫功能的发挥,使支原体对宿主产生严重的免疫逃逸。其中,(GAA)n基序已被证实在pMGA基因表达调控中起重要作用,这一三联体重复基序数目的多少直接影响到pMGA基因的ON/OFF不,本文通过对鸡败血支原体pMGA多基因家分子生物学研究进展浅要综述,以提出pMGA基因可能的转录调控机制,这对研究鸡败血支原体的分子致病机理及其免疫机制大有裨益。 相似文献
994.
R. L. Villareal A. Mujeeb-Kazi E. Del Toro J. Crossa S. Rajaram 《Journal of Agronomy and Crop Science》1994,173(5):307-317
Two trials were conducted at the Mexican National Institute of Agricultural Research Experiment Station at Yaqui Valley, Sonora, Mexico to investigate the nature and extent of agronomic variation in 50 synthetic hexaploid (SH) wheats (2n = 6x = 42, AABBDD) derived from Triticum turgidum (2n = 4x = 28. AABB) × T. tauschii (In = 2x = 14, DD) crosses for subsequent use in wheat improvement. Plant height, spike length, days to flowering, physiological maturity, grain yield, above-ground biomass at maturity, harvest index, yield components and test weight were determined.
Significant agronomic variation was observed among the germplasm evaluated. Outstanding SH genotypes were identified with higher grain yield, above-ground biomass at maturity, 1000-grain weight, and spikes m−2 than the bread wheat ( Triticum aestivum L.) check cultivar Seri 82. Genotypic correlations of grain yield with other character traits show that grain m2 was the most important determinant of gram yield (r = 0.993). Data on agronomic traits subjected to complete linkage cluster analysis resulted in classifying the genotypes into two distinct phenotypic groups excluding Seri 82. Groups generally corresponded to durum progenitors of the SH with significant group differences for all characters. This demonstrates use of practical numerical analysis procedures to describe agronomic variation in representative SH genotypes. Clustering by quantitativy traits may be valuable for identification of genotypes with divergent sources for breeding and agronomic purposes. 相似文献
Significant agronomic variation was observed among the germplasm evaluated. Outstanding SH genotypes were identified with higher grain yield, above-ground biomass at maturity, 1000-grain weight, and spikes m
995.
996.
将69头肺炎奶犊牛分成3组,分别为24,25和20头,分别应用双莴连注射液。氨基苄青霉素和恩诺沙星进行治疗,治愈率分别为62.5%,,68.0%和90%,治愈时间分别为11.3±1.20,9.8±1.4和4.4±1.1d。治疗结果表明恩诺沙星组的治疗效果明显优于另外2组,该药可作为治疗犊牛肺炎的首选药物。 相似文献
997.
黄山松球果生命表的研究 总被引:6,自引:2,他引:4
1992-1994年,在浙江省天台县华顶林场北山区铁泉湖黄山松种子园研究了黄山松球果生命表。结果表明,从雌球花开放球果成熟过程中,导致球果死亡的主要因子是松实小卷蛾幼虫的危害。 相似文献
998.
Nils Ek 《Acta veterinaria Scandinavica》1980,21(4):482
Studies of Pr protein concentrations in sera of sick horses were carried out using Mancini et al.’s (1965) immunodiffusion technique. Relative values against a chosen standard of 100 % were determined for a total of 102 horses. Horses with acute infections had Pr protein values significantly above the normal. The highest individual Pr protein value recorded in this group was 202. Horses suffering from acute laminitis and malignant tumours also had increased Pr protein values.There was a positive correlation between the Pr protein value and the blood leucocyte count and a negative correlation between the Pr protein value and the albumin content in serum. 相似文献
999.
1000.
对海南产区感染花叶病的香蕉病株进行生物学分离获得一种直径为28—30nm的球形病毒分离物,该分离物汁液接种可引起香蕉花叶症状,并侵染一些黄瓜花叶病毒(CMV)的诊断寄主植物,提纯病毒外壳蛋白由一种分子量约为3.2×10~6道尔顿的亚基构成,琼脂免疫双扩散试验表明,该病毒分离物和CMV有血清学关系,根据这些性质该病毒分离物被鉴定为黄瓜花叶病毒。 相似文献