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31.
随着我国综合国力的稳步发展,城乡人民的生活水平也不断提高,发展瓯柑种植面积和提高产量,改善瓯柑品质,是人们物质生活的需要,也是我国新形势下农业产业结构调整的发展趋势,并带动山区农民共同致富,利国又利民。本文就温州地区发展山园瓯柑节水喷灌机械配套节本增效技术进行叙述,对于推广应用具有重要的现实意义。 相似文献
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根据现有的矸石山自燃发生理论和防治技术原理以及困难立地条件下植被生态恢复理论,结合十一五国家科技支撑计划项目专题陡坡绿化喷播技术研究与开发的研究内容,在矸石山植被生态恢复工程实践中探索出一套技术装备、两类泥浆配方、多种喷射施工工艺的机械化综合治理技术方案,将矸石山自燃防范措施与高陡边坡植被重建技术有机地结合起来,创造出一种符合循环经济要求、成本低廉、可机械化高效率施工的方法。 相似文献
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密闭空间药雾浓度测量的试验方法研究 总被引:1,自引:3,他引:1
运用改进后的大气采样器,建立了一种对密闭空间细雾流分批采样分批分析的研究方法。对于采样参数组合的选取以及双侧采样的空间差异性进行了研究和统计判断,得出了最佳采样参数组合为采样时间5min,采气量5L/min。基于最佳采样参数组合,发现沉降曲线中存在分段点现象,分段点在喷雾结束后13min,也即开始喷雾后27min附近。针对分段点现象,给出了分段拟合的细雾流浓度沉降曲线及解析描述。采用改进的大气采样器可以获取喷雾结束后79rnin内的浓度数据,文献[13]中所用的采样方法只能得到喷雾结束后45min左右的浓度数据,因此该方法对药雾浓度沉降曲线的尾部特征描述能提供更多的信息。 相似文献
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Manganese (Mn) deficiency may be induced by adding large quantities of iron (Fe), provided that soil manganese is marginally deficient. Results of a greenhouse study showed that iron soil application did not influence shoot dry matter yield of dry bean due to the fact that the iron:manganese ratio in aerial parts of dry bean was higher than 0.4. A foliar spray of 2% iron sulfate significantly reduced it probably due to the high level of shoot iron and iron:manganese ratio greater than 4. Iron application decreased concentration/uptake of shoot manganese due to the iron-manganese antagonistic relationships. Mangenese soil application is not an effective method in correction of manganese deficiency induced by iron fertilizers. Iron did not affect root manganese uptake, indicating that manganese absorption was not affected by iron application. Both manganese/iron soil tests are recommended in calcareous soils with manganese soil test in marginal range. 相似文献
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五种叶面喷施剂对茶树增产效应的对比试验 总被引:1,自引:0,他引:1
2011年在飞竹镇梧桐村茶园内,用茶丰素、茶博士、茶叶催芽素、磷酸二氢钾、尿素等五种叶面喷施剂进行对比试验。实验结果表明:五种叶面喷施剂都有一定的增产效果和经济效益,但以茶丰素的作用最佳,茶博士、茶叶催芽素、磷酸二氢钾的作用又优于尿素。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(4):528-544
This study is a synthesis of information on growth, yield, and boron-use efficiency of hybrid sunflower (cultivar Aditya) in an inceptisol (Gangetic alluvium) of West Bengal, India, under varied proportions of soil and foliar-applied boron. Foliar spray of boron (B), under all circumstances, performed better than soil application of B fertilizers with regard to sunflower seed and total dry-matter yield, B uptake, and B-use efficiencies, while 0.2 percent foliar B spray was associated with greatest B recoveries, B-use efficiencies, and sunflower seed yields in the experimental years. 相似文献
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Improved planting methods and foliar application of glycinebetaine (GB) and salicylic acid (SA) can improve the water productivity in field crops under limited water supply conditions. A 2‐year field study was conducted to evaluate the possible role of different planting methods and foliar applications of GB and SA in improving the yield, quality and water productivity of hybrid sunflower (Helianthus annuus L.). The crop was planted by flat sowing (75 cm spaced rows) and ridge sowing (75 cm spaced ridges), with GB and SA applied exogenously at 100 and 0.724 mm , respectively, at both budding and flowering stages, while control plots received distilled water. Ridge sowing, rather than flat sowing, improved the biological yield, oil yield, leaf area index (LAI), crop growth rate (CGR), plant height, water‐use efficiency and final achene yield during both the years. Foliar applications of GB and SA at both the stages improved the achene yield, although foliar application of GB at flowering was the most effective. Neither the planting methods nor the foliar application of GB and SA altered the achene oil contents during both the years. Foliar application of GB and SA increased the free proline content of the leaf and GB contents at flowering but reduced the achene protein contents, whereas planting method had no effect on these attributes across the years. Of the foliar applied chemicals, GB was more effective in improving sunflower growth and yield and water productivity than SA. To conclude, ridge sowing coupled with foliar application of GB at flowering stage could be beneficial for achieving maximum yields of hybrid sunflower under relatively water limited conditions in the field. 相似文献