Effect of Gibberellic Acid Spray and Basal Nitrogen and Phosphorus on Productivity and Fatty Acid Composition of Rapeseed-Mustard

Two field experiments were conducted during] 994-95 to study the effect of spray of 10⁻⁵ M GA3 at 40 days after sowing on mustard ( Brassica juncea (L.) Czern & Coss.) cv. Varuna grown with basally applied 0, 40, 80 and 120 kg N ha⁻¹ (Expt. 1) and 0,15, 30 and 45 kg P ha⁻¹ (Expt. 2) on pod number per plant, seeds per pod, 1000 seed weight, seed yield, biological yield, harvest index and fatty acid composition of oil. No significant difference between water and GA3 spray was found when basally applied nitrogen was 0 or 40 kg N ha⁻¹. N₈₀ proved to be the best for yield characteristics. In another experiment on phosphorus, GA₃ and 30 kg P ha⁻¹ individually enhanced the yield, but interaction of GA₃ and P remained non-significant. The fatty acid composition of oil in both experiments was significantly affected only by nitrogen and phosphorus treatments for oleic acid and erucic acid. It was found that return in the form of yield was more for every kg applied fertilizer under GA, spray treatment. The response was more for N fertilizer in comparison to P. GA₃ at a low level of fertilization significantly increased the return from fertilization.     

德系安格拉毛用兔日粮最适营养水平探讨

本试验选用德系安格拉成年毛用兔80只,研究了其日粮不同粗蛋白(CP)、含硫氨基酸(SAA)和粗纤维(CF)水平对产毛性能的影响。结果表明,日粮中CP水平以16%～18%为宜,过高的CP水平并不能提高产毛率和毛的质量;日粮中SAA水平以0.65%～0.85%为宜,日粮配方中添加一定量的蛋氨酸能显著提高产毛性能;日粮中CF水平以14%左右提高毛的产量和质量为最佳,过精的日粮不仅造成浪费,而且对产毛性能并没有好处。     

酸性醇醚磷酸酯中单、双酯含量的测定

以三氯氧磷和醇醚为原料合成的醇醚磷酸酯中含有大量盐酸,盐酸的存在影响产品中单、双酯含量的确定.通过测定氯离子含量可间接确定醇醚磷酸酯中的盐酸含量,从而可较准确的测定单酯、双酯、三酯及磷酸含量.     

Evaluation of some systems for classifying soil sensitivity to acid deposition in the South African highveld

Abstract. The Skokloster and Stockholm Environmental Institute (SEI) approaches were applied to the assessment of 145 soils of the South African highveld region in terms of sensitivity to acid deposition. The critical load class calculated by variants of these methods was compared with the acid neutralizing capacity (ANC) determined by pH measurement of soil suspended in a dilute acetate buffer solution. This rapid index of ANC correlates well both with ANC determined by an established but more laborious method which involves titration and equilibration of soil with HCl, and with a number of soil properties related to base status. The correlation between Skokloster or SEI critical load classes and ANC was weak. It was concluded that ANC determination would be a preferable basis for classifying these soils in terms of their sensitivity to acid deposition, since the method is direct and integrates the contribution of various soil properties to acid sensitivity instead of requiring the relative contribution to be calculated according to somewhat arbitrary weightings given to broadly defined classes of soil properties.     

热水溶出茧层丝胶蛋白的结构变化

对不同时间热水溶出的茧层丝胶的氨基酸组成、热分解温度和分子结构等进行了测定分析．结果表明，随着热水溶出时间的延长，茧层丝胶蛋白中的酸性氨基酸因易溶于水而略有下降，热分解温度因受取向性、结晶性的影响而有所增高，分子结构也由无规则卷曲转化为β构象．丝胶蛋白被降解而成分子大小不一的混合类型     

午潮山常绿阔叶林气候生态效应定位研究

午潮山常绿阔叶林气候生态效应，经过８年（１９８８￣１９９５）定位观测研究，取得了若干规律性数据，加深了对常绿阔叶林生态系统气候生态学特征的认识，为持续经营、保护、利用和发展常绿阔叶林，提供了一定的科学依据。文中较系统地论述了午潮山常绿阔叶林的日照、温度、湿度，林内降水量再分配，酸雨等问题。     

Chloroacetic acids—Degradation intermediates of organic matter in forest soil

Chloroacetic acids (CAA), especially trichloroacetic acid (TCA), were considered phytotoxic secondary air pollutants of anthropogenic origin affecting conifers and were therefore intensively studied. However, another source of CAA has been then found: a forest soil in which humic substances are degraded by microbial processes to CAA and chloroform. This new aspect—formation of CAA in the soil—means that CAA are continuously produced and also biodegraded by other microorganisms in the soil and contribute thereby to the degradation of soil organic matter (SOM). Here we show for the first time the formation of dichloroacetic acid (DCA) and TCA in the forest soil by chlorination of SOM using ³⁶Cl labeled chloride. We suggest that CAA are both formed and biodegraded in the forest soil and thus represent intermediates in one of the processes of SOM decay.     

含N三臂类肽的合成

利用胺分子中氮原子成键的空间特征，接上3个含有S，N杂原子的氨基酸侧链从而合成了穴醚状含N三臂类肽，其独特的分子结构对客体识别具有重要的实践价值．     

Effect of pollination on cell division,cell enlargement,and endogenous hormones in fruit development in a gynoecious cucumber

To study the effect of pollination on fruit development in gynoecious and parthenocarpic cucumbers (Cucumis sativus L. cv. NK × AN8), the number of cells, cell size, mitotic index, histone H4 gene expression, and concentrations of endogenous cytokinins and auxin were compared in fruits that had developed from pollinated and non-pollinated flowers. Fresh weight was more in the pollinated group 4–12 days after anthesis (DAA) in both winter and spring, and 2–6 DAA in the summer. In winter, mitotic index increased from anthesis to 2 DAA and then decreased gradually in the pollinated group but immediately after anthesis in the non-pollinated group. Histone H4 gene in the pericarp zone was expressed more strongly during the period from pre-anthesis to 2 DAA in the pollinated group in summer. Concentrations of zeatin, isopentenyladenine, and indole-3-acetic acid (IAA) were higher in the non-pollinated group 2 and 4 DAA and peaked 4 DAA in spring whereas isopentenyladenine and IAA showed no distinct peaks in the pollinated group. These results are incompatible with the idea that pollination activates cell division by stimulating the synthesis of cytokinins and auxin in cucumber fruits.