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991.
有机硅表面活性剂Tech-408和Fairland2408对农药雾滴在烟草叶片上覆盖面积的影响 总被引:1,自引:0,他引:1
[目的]研究有机硅表面活性剂Tech-408和Fairland2408对农药雾滴在烟草叶片上覆盖面积的影响,寻找提高农药使用效率的途径.[方法]将10%吡虫啉乳油稀释3 000倍,分别加入有机硅表面活性剂Fairland2408和Tech-408以及农乳500#后,采用连续拍摄的方法,测试直径范围为340~360 μm单个雾滴在‘NC471,、‘云110,和‘T66'3种烟叶片上的蒸发时间和覆盖面积,重点研究Fairland2408和Tech-408对药液雾滴在烟草叶片上覆盖面积的影响规律.[结果]表面活性剂不同,雾滴覆盖面积的扩展程度也不同.当Tech-408、Fairland2408和农乳500#的添加比例为0.03%时,雾滴覆盖面积在上述3种烟叶片上扩展的平均倍数分别为8.1、6.4倍和1.2倍.表面活性剂添加比例不同,其对农药雾滴覆盖面积的影响程度也明显不同.随着Tech-408、Fairland2408和农乳500#的添加比例从0.03%增加到0.1%,雾滴在‘T66’烟叶片上覆盖面积分别增大了39.8%、156.1%和53.3%.[结论]有机硅表面活性剂Tech-408和Fairland2408和其添加比例均对吡虫啉在烟叶上的雾滴覆盖程度有明显影响. 相似文献
992.
993.
Based on the trace of origin and development process of low-carbon economy, the paper defined the concept of low-carbon agriculture. As a case, the development of low-carbon advantage and disadvantage of agriculture in Heilongjiang Province made a systematic analysis of factors; it based on the empirical and comparative analysis of low-carbon development in Heilongjiang Province and put forward countermeasures and suggestions of agriculture. At last, the low-carbon agriculture was prospected in the future. 相似文献
994.
Panax ginseng is an indigenous medicinal herb and has traditionally been used among Asian population for relief of many human ailments. We investigated the prophylactic role of Korean P. ginseng extract (KG) against X-ray irradiation-induced emesis in an acute rat pica model. Rats were treated with KG (12.5, 25, 50 mg/kg orally at -48, -24 and 0 h) prior to X-ray irradiation (6 Gy), and intake of kaolin and normal food and body weight changes examined as an index of the acute emetic stimulus. Levels of serotonin in small intestine tissue were assessed and histopathology of gastric tissue, small intestine and colon examined specific staining. Pre-treatment with KG (12.5 and 25 mg/kg) reduced X-ray irradiation-induced kaolin intake at 24h. Normal food intake was improved in rats treated with 25 mg/kg KG. The anti-emetic effect of KG was further confirmed on the basis of serotonin release, histopathological findings. Our findings collectively indicate that KG protects against X-ray irradiation-induced acute pica to a moderate extent, leading to improved feeding behavior in rats. 相似文献
995.
Plants in the alpine zone mainly depend on the reserved food materials stored in their rhizomes for the next growing season.We investigated the effect of mixed cropping(Phaseolus vulgaris L.var.Pinto) with four rhizomatous medicinal plants,i.e.,Angelica glauca,Arnebia benthamii,Rheum emodi and Pleurospermum angelicoides as well as three levels of water stress treatment under two conditions(shade net and open field) on macronutrients(NPK) and biochemicals(carbohydrates and protein).The experiment was conducted by completely randomized design(CDR).The data were analyzed with ANOVA as well as CDR.The experimental results show that in all the species shade conditions with sever water stress(SSWS) increased the level of macronutrients(NPK).However,(N) concentration was highest under shade with mixed cropping(SMIX).Under SMIX,carbohydrate content was highest than open field control conditions(CONT).This investigation results demonstrate that mixed cropping of medicinal plants with Phaseolus vulgaris could be a good livelihood option in the mountainous regions of Indian Central Himalaya.And the water-stress conditions along with mixed cropping could improve the biochemical constituents in the rhizome of these species. 相似文献
996.
介绍了微型生物群落监测法、指示生物法、污水生物系统、生物标志物等不同的湿地水生生物监测方法,并对未来的工作提出了展望。 相似文献
997.
B. Sarath Babu S.R. PandravadaR.D.V.J. Prasada Rao K. AnithaS.K. Chakrabarty K.S. Varaprasad 《Crop Protection》2011,30(4):389-400
Today India is the main producer of peppers especially the hot peppers, albeit mostly for domestic use. The thrips and mites, and the virus diseases transmitted by them along with fungal diseases like fruit rot, powdery mildew, bacterial wilt and leaf spots are the limiting factors in pepper productivity. The solution for managing these pests on a sustained basis exists in adopting eco-friendly approaches like using resistant cultivars. Fortunately huge natural genetic diversity exists in pepper and therefore, essential research efforts in finding out resistant sources and their utilization have been by and large dynamic and successful. Despite continuous scientific efforts there is a dire need for new cultivars with resistant traits for various pests suitable to varied climatic conditions, consumption and quality preferences all over the world. Efforts need to be intensified to find out useful genetic material and to introduce genes of resistance against insects, fungal and virus diseases into commercial cultivars. Genetic resources that have been used intensively in pepper breeding are for developing sweet peppers, hot peppers, bell peppers in various shapes, sizes and colors. Germplasm repositories at the World Vegetable Research Center (AVRDC) and United States Department of Agriculture (USDA) do possess number of genotypes resistant to insect pests, nematode, fungi, bacteria and virus diseases. At AVRDC resistant genotypes originating from several pepper growing countries to most virus diseases like Tobacco mosaic virus, Cucumber mosaic virus, Pepper veinal mottle virus, Chilli veinal mottle virus, Peanut bud necrosis virus etc., were identified from its rich pepper diversity. Exploitation of rich genetic diversity resulted in the development of new cultivars encompassing resistance to various pests and good agronomical traits. This has eventually resulted in meeting the demanding situations of diverse domestic as well as global production requirements. The chile database (Chile Database, 2010) highlights the exemplary utilization of germplasm and development of large number of cultivars and hybrids resistant to most diseases and nematodes around the world. This paper also depicts information on Indian sources of resistance to thrips, mites, leaf curl complex, nematodes and diseases, while presenting the scope for exploitation of diversity available in the Indian National Gene Bank and other repositories all over the world. An attempt is also made to identify the gaps in the genetic diversity and cultivars against the biotic constraints and the augmentation efforts required to be initiated toward enrichment of the gene pool for domestic as well as global use. 相似文献
998.
充分运用现代信息技术开展教学实践活动,有利于激发学生学习热情,实现最优化教学.福建林业职业技术学院教师在教学过程中,通过信息技术和多媒体演示,实现地形图三维动态演示教学,活跃了课堂气氛,激发了学生求知欲,在提高教学质量,建立新型师生关系等方面起到了良好作用. 相似文献
999.
Govind Pratap Rao Madhupriya Ajay Kumar Tiwari Shailendra Kumar Virendra Kumar Baranwal 《Phytoparasitica》2014,42(3):349-354
During a survey of sugarcane fields at the Sugarcane Research Institute, Shahjahanpur, Uttar Pradesh, India, in August–September 2012, 6% to 28% incidence of sugarcane grassy shoot disease was observed in different fields of sugarcane variety CoS 7250. The association of phytoplasma with symptomatic sugarcane was confirmed by direct and nested PCR amplification of phytoplasma ribosomal gene. Four different delphacid leafhopper species, viz. Cofana unimaculata Signoret, Exitianus indicus (Distant), Sogatella kolophon Kirkaldy and Hishimonus phycitis (Dist.) were the prevalent feeding species of the Auchenorrhyncha fauna in the symptomatic sugarcane fields. Out of these four leafhopper species, only E. indicus tested positive for phytoplasma presence. Phylogenetic analysis suggested that the phytoplasmas from sugarcane and E. indicus in the present study were members of 16Sr XI. The confirmation of association of sugarcane grassy shoot phytoplasma in E. indicus population is important to understand the secondary spread of this phytoplasma in sugarcane plants. 相似文献
1000.
Salt Stress Delayed Flowering and Reduced Reproductive Success of Chickpea (Cicer arietinum L.), A Response Associated with Na+ Accumulation in Leaves
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R. Pushpavalli J. Quealy T. D. Colmer N. C. Turner K. H. M. Siddique M. V. Rao V. Vadez 《Journal of Agronomy and Crop Science》2016,202(2):125-138
Salinity is known to reduce chickpea yields in several regions of the world. Although ion toxicity associated with salinity leads to yield reductions in a number of other crops, its role in reducing yields in chickpea growing in saline soils is unclear. The purpose of this study was to (i) identify the phenological and yield parameters associated with salt stress tolerance and sensitivity in chickpea and (ii) identify any pattern of tissue ion accumulation that could relate to salt tolerance of chickpea exposed to saline soil in an outdoor pot experiment. Fourteen genotypes of chickpea (Cicer arietinum L.) were used to study yield parameters, of which eight were selected for ion analysis after being grown in soil treated with 0 and 80 mm NaCl. Salinity delayed flowering and the delay was greater in sensitive than tolerant genotypes under salt stress. Filled pod and seed numbers, but not seed size, were associated with seed yield in saline conditions, suggesting that salinity impaired reproductive success more in sensitive than tolerant lines. Of the various tissues measured for concentrations of Cl?, Na+ and K+, higher seed yields in saline conditions were positively correlated with higher K+ concentration in seeds at the mid‐filling stage (R2 = 0.55), a higher K+/Na+ ratio in the laminae of fully expanded young leaves (R2 = 0.50), a lower Na+ concentration in old green leaves (R2 = 0.50) and a higher Cl? concentration in mature seeds. The delay in flowering was associated with higher concentrations of Na+ in the laminae of fully expanded young leaves (R2 = 0.61) and old green leaves (R2 = 0.51). We conclude that although none of the ions appeared to have any toxic effect, Na+ accumulation in leaves was associated with delayed flowering that in turn could have played a role in the lower reproductive success in the sensitive lines. 相似文献