向镰刀菌毒素污染的谷物添加葡甘露聚糖对初产母猪生产性能和血液生化指标的影响

研究表明,镰刀菌毒素会导致泌乳母猪的采食量和日增重下降,具有延长母猪从断奶至发情间隔时间的倾向;葡甘露聚糖能够防止由镰刀菌毒素毒性作用引起的血清尿素和总蛋白浓度的下降。     

不同含水率对油莎豆物理特性及力学特性的影响

为探究不同含水率条件下油莎豆的物理特性及力学特性,减少油莎豆在收获、干燥、清洗等过程中受到挤压摩擦而产生的机械损伤,开展5种含水率(20%,25%,30%,35%,40%)水平下油莎豆的主要物理特性及力学特性试验。试验结果表明,含水率在20%～40%范围内,随着含水率的升高,油莎豆平均几何粒径显著增加;滚动摩擦系数呈线性增加;而最大破碎力呈先增大后减小趋势,在含水率为30%时达到最大值210.169 N。根据试验结果,分别拟合得到油莎豆压缩特性、摩擦特性、休止角与含水率的关系方程,为油莎豆播种、收获、干燥、清洗等装备设计及参数优化提供技术依据。     

THE HERBICIDAL EFFECT OF SOME SUBSTITUTED ANILIDES

Summary. The 3,4-dichloroanilides of four herbicidally active and of four inactive or weakly active phenoxyalkanecarboxylic acids were synthesized and tested for herbicidal activity, in order to study the effect of compounds comprising the two characteristic groupings within one molecule. 4-Chloro-2-methylphenoxyacetic acid, 2,4-dichloro-phenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid and a-[2,4,5-trichlorophenoxy] propionic acid were selected as representatives of active compounds; and phenoxyacetic acid, 2-methylphenoxyacetic acid, 3,5-dichlorophenoxyacetic acid and 2,4,6-trichloro-phenoxyacetic acid as inactive or weakly active compounds.
The compounds were tested in the glasshouse on wheat and white mustard as pre-and post-emergence treatments. The synthesized 3,4-dichloroanilides had no or little herbicidal activity, as compared with the high activity of the known herbicides 3,4-dichloropropionanilide and 2,4-dichlorophenoxyacetic acid. The conclusion can be drawn that the introduction of phenoxy groupings into the acid moiety of the active fatty acid-3,4-dichloroanilides as well as the introduction of the 3,4-dichloroaniline group into the carboxylic group of the active phenoxyacetic acids decreases herbicidal activity. This last phenomenon is probably due to a decreased ability to be hydrolysed.
L'activité herbicide de quelques anilides substituées     

THE EFFECT OF MCPA ON THE AMINO ACID AND SUGAR COMPOSITION OF VICIA FABA LEAVES

Summary. The effect of spraying Vicia faba leaves with 5000 ppm MCPA is described. Three to 4 days after spraying, a marked increase (× 5 approx.) was found in the concentrations of leucine iso -leucine and valine in the leaves. No significant changes were detected in the other amino acids. Treatment with MGPA also caused a significant increase (× 4 approx.) in the glucose and fructose content of the leaves. Detached leaves (sprayed and unsprayed), when kept in a moist atmosphere for 3–4 days, exhibited very similar increases in amino acids and sugars to sprayed intact plants. Experiments using ¹⁴CO₂ revealed that in short term photosynthesis (30 min) of sprayed and unsprayed plants, 80–90% of the radioactivity was incorporated in sucrose, with about 5% in each of glucose and fructose. Over photosynthelic periods of 4 days, glucose and fructose were found to be almost as heavily labelled as sucrose in sprayed plants, but in the controls the distribution of radioactivity was similar to that in short term photosynthesis. It is suggested that the build up of amino acids and sugars in plants treated with MCPA is due to an interruption of the translocatory flow from the leaves, and that this build up of metabolites may be a contributory factor in the toxic action of this herbicide.
Effet du MCPA sur la composition en amino-acides et en sucre des feuilles de Vicia faba