农药市场常见违法行为分析与建议

本文对四川省近5年立案查处的农药市场违法案件进行整理,对案例反映出的农药市场常见违法行为进行归类分析,并提出了相应的监管建议,试图给农药市场监管工作提供参考。     

The mechanical roles of the clasping leaf sheath in cereals: Two case studies from oat and wheat plants

Stem lodging is a common problem in cereal crop production and a main constraint for grain yield improvement. The leaf sheath that surrounds and protects the hollow internodes of stem could provide the plants with a great physical support. However, this biomechanical function has been ignored for several decades in cereal crops. This study aimed to examine the biomechanical properties of basal stem internodes and lodging susceptibility of the whole plants with or without the clasping leaf sheath in wheat (Triticum aestivum L.) and oat (Avena sativa L.) among different genotypes and agronomic practices (including planting densities and nitrogen application rates). The main objective was to quantify the mechanical role of the leaf sheath in oat and wheat crops by a “safety factor” method. On average, the leaf sheath contributed 40%, 68% and 38% of the overall stem bending strength, flexural rigidity and safety factor, in oat, while it accounted for 11%, 24% and 10%, respectively, in wheat plants. The significant contribution of the leaf sheath is due to its vital role in enlarging the peripheral position (i.e., second moment of area) and stiffness (i.e., Young's modulus). The contribution ratios (%) were found to be higher in oat than in wheat plants, due to the greater mass density of leaf sheath and more proficient/prevailing stay-green capability in oat genotypes. This study emphasizes the important mechanical role of clasping leaf sheath on stem internodes of cereals and indicates that the stay-green trait of the leaf sheath can be exploited to design appropriate varieties with improved lodging resistance and great yield potential.     

不同保水处理下苏丹草光合特性研究

为了研究矿区生态修复过程中植物对不同保水措施的生理响应,以常用修复植物苏丹草为研究对象,利用CIRAS-2型(PP-Systems)光合仪测定苏丹草的光合指标,探讨高温下苏丹草对不同保水措施的生理响应,以期为矿区生态修复中的保水措施提供理论依据。结果表明：不同保水处理下苏丹草的光合速率Pn和瞬间水分利用效率WUE日变化均呈“W”型曲线,蒸腾速率Tr日变化呈“M”型曲线。苏丹草的Pn有“午休”现象存在,主要受非气孔因素的影响。影响苏丹草Pn、Tr的主要环境因子为大气CO₂浓度Ca、大气温度Tc、大气相对湿度RH。在土壤上覆盖火烧石和添加粉煤灰均显著增大了苏丹草的Pn和WUE,增强了苏丹草适应高温环境的能力。从Pn的指标来看,土壤表面覆盖火烧石处理比土壤中添加粉煤灰处理的效果好,但两者同时作用效果略低于单独用火烧石处理,原因有待进一步研究。     

沼气池热传递过程研究进展

温度是沼气工程高效运行的关键,沼气发酵不仅要维持适宜的温度,还须保证温度的稳定性。为此,对沼气池热传递过程的相关研究进行分析介绍,主要包括沼气池发酵液温度的影响因素、发酵系统热流损失、增温方式和热传递模型研究,并指出增温方式的选择应建立在正确的热过程分析基础上,建议进一步改进优化热传递模型,更好地指导沼气工程实施。     

阿勒泰羊生长速度与主要血液生化指标含量及尾脂Leptin基因表达关系

试验通过研究不同生长速度阿勒泰羊主要血液生化指标含量和尾脂中瘦素（Leptin）基因的表达水平，探讨阿勒泰羊生长速度与脂肪沉积之间的关系。选取300只出生时间相近的阿勒泰羊公羔，正常饲喂至6月龄，记录日增重，取平均日增重排前10%和后10%的公羔各30只，分为生长快速组（HBW）和生长慢速组（LBW），从生长快速组随机选12只分为抑制生长组（饲喂低能量饲粮以抑制其生长，HBW-75%，n=6）和生长快速对照组（饲喂标准饲粮，HBW-100%，n=6），生长慢速组随机选12只分为促进生长组（饲喂高能量饲粮以促进生长，LBW-125%，n=6）和生长慢速对照组（饲喂标准饲粮，LBW-100%，n=6）；预饲期7 d，正饲期30 d，试验结束后称重并采集血液，屠宰后采集尾部脂肪。检测血液TG、CK、TSH、T3、T4、S.S、GH、INS、PG、Leptin含量或活性及尾部脂肪Leptin mRNA和蛋白表达量，并观察尾部脂肪细胞形态学变化。结果显示，HBW-100%和LBW-100%组初体重与末体重均差异显著（P<0.05），HBW-75%和HBW-100%组初体重与末体重均无显著差异（P>0.05）；LBW-100%和LBW-125%组初体重差异显著（P<0.05），末体重无显著差异（P>0.05）。LBW-100%组的T4、S.S、Leptin、TSH、T3含量显著低于HBW-100%组（P<0.05）；LBW-125%组T3含量显著高于LBW-100%组（P<0.05）；HBW-75%组GH、PG和Leptin含量显著低于HBW-100%组（P<0.05）。LBW-125%组尾部脂肪细胞面积大于LBW-100%组，HBW-75%组小于HBW-100%组（P<0.05）。Leptin mRNA和蛋白表达量检测结果表明，HBW-100%组的Leptin mRNA表达量与LBW-100%组无显著差异（P>0.05），Leptin蛋白表达量极显著高于LBW-100%组（P<0.01）。LBW-125%组Leptin mRNA和蛋白的表达量均显著高于LBW-100%组（P<0.05）。HBW-75%组Leptin mRNA的表达量极显著低于HBW-100%组（P<0.01），Leptin蛋白表达量显著低于HBW-100%组（P<0.05）。综上所述，生长快速组与生长慢速组中，Leptin的表达量与体重和体脂有一定关联；在生长慢速组促进生长后体重和体脂显著增加，Leptin的表达量呈上升趋势；在生长快速组抑制生长后体重和体脂减少，Leptin的表达呈下降趋势。改变生长速度对Leptin的表达量会产生影响，从而改变机体的脂肪沉积状况。     

浅议农业科研单位固定资产如何计提折旧

文章针对农业科研单位固定资产折旧作了初步分析,从固定资产计提折旧的重要性、计提方法、会计核算及存在的问题等方面进行了一些探讨。     

心房钠尿肽基因敲除小鼠的鉴定

研究心房钠尿肽基因敲除小鼠(ANP-/-小鼠)的生物学及病理学特性。ANP-/-小鼠与C57BL/6小鼠饲养于SPF级环境中,观察小鼠的繁育状况及其生物学特性,选取合适时间处死小鼠,通过HE染色观察脏器形态及组织结构。ANP-/-小鼠的繁殖周期比C57BL/6长,产仔率较低;ANP-/-小鼠肝脏、肺脏、脾脏较C57BL/6小鼠的有明显炎症反应,但是C57BL/6小鼠未见明显的病理改变。提示ANP基因的缺失可能与炎症发生有关。说明ANP-/-小鼠繁殖较慢、产仔率低,且正常繁殖的普通小鼠不会引起器官的病理学改变。但作为一种在心血管、代谢疾病上的动物模型,并与炎症甚至肿瘤有可能的未知联系的转基因动物,其很有研究和探索价值。     

后备公猪的科学选育与利用

后备公猪的科学选育及利用直接影响猪场制种效果和经济效益,同时也能体现规模化猪场的制种技术与水平。文章针对后备公猪选育的基本环节和操作要点,从如何选种选育、科学饲养管理、合理配种利用等方面进行系统阐述,为规模化猪场后备公猪生产提供技术指导和参考依据。     

Effects of Glyphosate on Soil Salinization and Alkalization in Cotton Fields

We analyzed the effects of glyphosate to the index of salinization and alkalization by simulation in soils collected from cotton fields in Anyang, Henan and Anqing, Anhui, China, in 2014. The results showed that application of glyphosate changed electrical conductivity (EC), total alkalinity (TAL), exchangeable sodium percentage (ESP), sodium adsorption ratio (SAR) and pH of soil in both regions，compared with the blank control. With increased frequency of glyphosate application and increased concentration applied, all indices increased in the Anqing cotton fields soil which were treated with concentrations of 2.5-20 g·L^－1 . However, EC, TAL and ESP increased dynamically in Anyang soil to which high concentrations of 20 g·L^－1 were applied only four consecutive times. After different glyphosate treatments, the soil pH value showed an upward trend but smaller changes. Therefore, after repeated use of glyphosate to soils of two different region soils, although the changes of all indices were within the range of non-saline and non-sodic soils, the soils affected by salt in the glyphosate aqueous solution tended towards saline-sodic soils.