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71.
大兴安岭北部林区森林防火基础设施建设项目是建国后国家一次性用于国有林区森林防火投资最大的基础设施建设工程。介绍了该项目建设的基本情况,总结了主要建设成效,分析了存在问题,提出了相关对策建议。  相似文献   
72.
高端人才的缺乏以及人才素质问题已经成为制约辽宁科技特派行动的主要因素。分析科技特派行动高端人才支撑体系在运行机制、体系构建及内外部协调等方面存在的问题,提出具体的完善措施。  相似文献   
73.
浅议通过标签内容查找农药隐性成分   总被引:1,自引:0,他引:1  
本文针对农药隐性成分危害大和监管难等问题,剖析了企业主要动机,以农药标签为对象,研究建立了一种查找"问题"农药、锁定农药隐性成分的方法。该方法具有成本低、易于普及、克服检测仪器谱库不足、发挥基层各方力量进行监管等优点。与检测技术结合使用,可以弥补各方不足,更好地发挥监管作用。  相似文献   
74.
Banana anthracnose incited by Colletotrichum musae is a serious disease in post harvest marketing stage. It occurs in almost all the banana growing countries. In the current study, 5 isolates of C. musae infecting banana cv nendran were collected from various district of Tamil Nadu. C5 isolate collected from Tiruchirappalli showed maximum virulent with (66.60%) PDI. In vitro efficacy of six Pseudomonas fluorescens superior strains were tested for their inhibition on mycelial growth of C. musae. P. fluorescens (FP7) showed significantly higher inhibition of 41.12 per cent over control and with a mean mycelial growth of 52.10 mm. Water in oil emulsion was used in the present research for formulation of P. fluorescens (FP7). The emulsion contained the following ingredients (w/w), sterile deionized water (45.25%), glycerine (4.00%), water-soluble wax ((0.75%), Tween 20 (2.50%), and a mixture of 19.00% soybean oil + 28.50% castor oil. The application of water in oil emulsion formulation significantly increased the yield (68.12 t/ha) compared to control (66.49 t/ha), and also increase in the activity of defense related enzymes viz., phenyl alanine ammonia lyase, peroxidase, polyphenol oxidase, catalase and β-1, 3 glucanase was observed which was followed by talc based formulation of Pf1 and FP7.  相似文献   
75.
据笔者在石塘镇水产畜牧兽医站工作十余年,本文对石塘镇牛品改工作存在的问题及整改措施进行了分析,只有剖析与解决了制约牛品改工作发展的不利因素,才能促进石塘镇牛品改工作的顺利发展,提高广大养殖户的经济收入。  相似文献   
76.
SmartStax® insect-protected corn (Zea mays L.) contains genes for six Bacillus thuringiensis (Bt) proteins controlling both lepidopteran pests and the corn rootworm complex (Diabrotica spp.). The properties of SmartStax, particularly the multiple effective modes of action (i.e., each Bt protein provides a high level of control of the target pests with a low probability of cross-resistance among the proteins), have provided the opportunity to add to previously approved structured refuge options by combining the non-Bt refuge seed with SmartStax seed in a seed mix. Seed mixes ensure that a refuge is present in every Bt field, remove concerns about grower compliance with refuge requirements, and provide grower convenience. However, seed mixes could increase the likelihood that larval insects move between Bt and non-Bt plants and vice versa. Assessing the insect resistance management (IRM) value of a seed mix refuge requires an assessment of the amount of larval movement, and the consequences of that movement, for the key target pests. The studies here present such data for control of corn rootworm by SmartStax corn, which contains the rootworm-active protein Cry3Bb1 and the binary protein Cry34Ab1/Cry35Ab1. In a growth chamber experiment, SmartStax was most effective against first instars and significantly effective against second instars, but did not control third instars. In a field study of movement from a heavily infested non-Bt plant onto surrounding plants, a larger percentage of insects successfully dispersed from the infested plant when the surrounding plants were non-Bt plants than when they were SmartStax plants. A paired-plant study showed that few larvae migrated from infested SmartStax plants and survived on nearby non-Bt plants; larvae that migrated from infested non-Bt plants had low survival if the adjacent plants were SmartStax. Replicated field studies of plant-to-plant movement indicated that the non-Bt plants in a 5% or 10% seed mix consistently supported large populations of susceptible insects and represented a productive refuge, whereas the SmartStax plants had few or no survivors. The timing of emergence from seed mix plots containing 5% or 10% non-Bt plants was more similar to that of the non-Bt plots than that of the SmartStax plots. Thus, the available growth chamber and field data indicate that a seed mix of 5% or more will provide an effective refuge for corn rootworm in SmartStax corn.  相似文献   
77.
通过Rusitec-s体外发酵系统研究不同粒度猫尾草对羔羊体外发酵参数与微生物数量的影响,选取6种不同粒度(1.00、2.36、3.35、4.75、8.00和12.50 mm)的猫尾草作为试验饲粮的纤维来源,按照猫尾草的粒度将试验分为6个处理组,每个处理4个重复,利用Rusitec-s型人工瘤胃模拟装置进行48 h体外发酵,测定养分降解率、发酵参数及发酵液中6种微生物菌群的拷贝数。结果表明:与其他处理组相比,2.36 mm组显著提高了体外中性洗涤纤维降解率(IVNDFD)、丁酸、异丁酸、戊酸、异戊酸摩尔比和溶纤维丁酸弧菌(B. f)数量(P<0.05),且显著降低总产甲烷菌(TMe)数量(P<0.05)。总菌(TB)与氨态氮(NH3-N)浓度、乙酸摩尔比呈正相关(R2=0.84,P=0.038;R2=0.88,P=0.021);B. f数量与丙酸摩尔比呈正相关(R2=0.82,P=0.045),且与pH呈负相关(R2=-0.98,P=0.001);TMe数量与体外粗蛋白质降解率(IVCP...  相似文献   
78.
Acetamiprid (ACE) and imidacroprid (IMI) are known neonicotinoid insecticides with strong affinities for the insect-selective nicotinic acetylcholine receptor. These provide insect control by hyperstimulating insect nerves and are used for agricultural pest management. However, it has also been reported that ACE and IMI affect mammalian reproductive function. We determined the effects of ACE and IMI on the in vitro maturation of porcine oocytes. Significant decreases in nuclear maturation rates were observed in the ACE or IMI-exposed groups. Also, in matured oocytes from the ACE or IMI-exposed groups, irregular chromosomes were observed. Our results suggest that ACE and IMI exposure was detrimental to porcine oocytes and the extent of the effects depends on the concentration of exposure.  相似文献   
79.
为更好地利用老芒麦(Elymus sibiricus L.)野生资源,本研究从我国青藏高原、西北、华北、东北地区以及国外部分地区共采集了1 723份野生披碱草属种质资源,通过表型特征观测和流式细胞仪检测,共鉴定出了990份野生老芒麦种质,246份垂穗披碱草种质,并测得老芒麦的DNA含量在5.86~7.30 Gb之间,平均DNA含量为6.66 Gb;垂穗披碱草材料的DNA含量在9.50~10.36 Gb之间,平均DNA含量为9.97 Gb。研究结果显示,在西北、华北以及东北地区的部分野生老芒麦材料在苗期基部叶鞘出现了绒毛,分析发现该表型出现的概率与经度和纬度呈极显著正相关关系(P<0.01),与海拔、年年均气温以及年平均降雨量呈极显著负相关关系(P<0.01)。表明老芒麦苗期基部叶鞘绒毛的有无与环境因子之间存在着必然的联系,可能是老芒麦种质应对不同环境类型的适应性机制之一。本研究为老芒麦的形态鉴定提供了新的依据,为老芒麦种质资源挖掘和育种应用提供了材料基础。  相似文献   
80.
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