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201.
橡胶高产综合技术开发试验十年总结报告 总被引:2,自引:0,他引:2
华南热带作物研究院于1982年开始,与海南省国营卫星农场合作进行“成龄橡胶芽接树高产综合技术的开发试验”,面积128.8hm~2,历时10年。高产综合技术措施包括:(1)挖沟盖草培肥;(2)营养诊断指导合理施肥;(3)乙烯利刺激高效低频周期割胶;(4)产胶动态分析指导割胶生产。试验结果表明,几项措施产生综合效应,能较大幅度提高产量。试验10年,试区干胶产量从试验前1149kg提高到1621.5kg/hm~2,而对照区则从1104kg下降至952.5kg;试区平均年增产干胶630kg/hm~2,增产率达63.6%。该技术的应用对胶树的生长量、死皮等副性状无明显不良影响。 相似文献
202.
冷季型草坪杂草综合防治技术与策略 总被引:6,自引:1,他引:5
冷季型草坪发展速度很快 ,但养护管理技术滞后 ,杂草危害严重。在调查掌握杂草的种类、数量及发生规律的情况下 ,应采取以下防治策略 :(1)严格杂草检疫制度 ,清洁播种材料 ;(2 )合理耕作 ,深埋杂草种子或幼苗 ,清洁坪床 ;(3)科学栽培管理 ,诱杀或抑制杂草 ,具体技术包括草种选择、播期、播量、施肥、浇水、修剪等 :(4)化学防除 ,具体包括播前诱杀除草 ,播后苗前和播后苗期除草 相似文献
203.
应用MD23A进行农用潜水电动机参数综合测试 总被引:1,自引:0,他引:1
张方 《东北农业大学学报》2008,39(4):14-17
应用MD23A电机参数综合测试仪及微型计算机进行农用潜水电机试验时,应用A/D转换器结合微型计算机,进行瞬时采样,测取数据组,进行数据处理后,应用数学方法和手段,绘制潜水电动机的工作特性曲线,对于产品生产企业,可以直接得到产品特性曲线,是生产潜水电机的企业的新型测试手段,具有广泛的意义。 相似文献
204.
退牧还草改善草地生态环境 总被引:8,自引:2,他引:6
针对青海省草地生态环境趋于恶化的实际状况,提出退牧还草,改善草地生态环境建议和措施一是种植优良牧草,建立高产优质的人工草地;二是发展牧区二、三产业,搞好畜牧业服务体系建设;三是大力推广使用优质饲料产品;四是压缩非生产畜,缓解草场压力,走高效畜牧业路子;开展草地生态综合治理. 相似文献
205.
砂土地肥料配施对小麦产量和土壤肥力的影响 总被引:1,自引:0,他引:1
彩四因子干净人通用旋转设计,研究了砂土地施用有机肥、氮、肥、磷肥和钾肥对小麦产量的作用和对土壤肥力的影响及其施肥因子之间的交互作用和最适配比。结果表明:有机肥、氮肥、磷肥和钾肥与小麦产量呈二次回归关系,砂土地要提高产量和培肥地力应立足于肥料配合施用,重施有机肥,酌情多施磷肥。 相似文献
206.
207.
Ian R. Crute 《Euphytica》1992,63(1-2):95-102
Summary Over the last 30 years, six resistance alleles (Dm2, Dm3, Dm6, Dm7, Dm11 andDm16) located in two linkage groups, have contributed to the control of downy mildew in lettuce crops grown under protection (glass or polythene) in northern Europe. More recently, an as yet genetically uncharacterised resistance factor, R18, has also begun to assume importance. The occurrence of the various combinations of these resistance alleles that exist in commercial cultivars has been dictated by the pathotypes ofBremia lactucae used in their selection but also restricted by linkage in repulsion. In the UK, a pathotype ofB. lactucae insensitive to phenylamide fungicides, such as metalaxyl, emerged in 1978 and became prevalent throughout lettuce production areas in subsequent years. The specific virulence of this pathotype was identical to the previously described phenylamide sensitive pathotype NL10 and cultivars carryingDm11, Dm16 or R18 were resistant. Consequently, an integrated control strategy based on the utilisation of metalaxyl on cultivars carryingDm11 provided effective control in UK until 1987 when a new phenylamide insensitive pathotype began to cause problems. The specific virulence of this second pathotype, which was first reported in the Netherlands and France, was identical to the previously described phenylamide sensitive pathotype NL15. Cultivars carryingDm6, Dm16 or R18, but notDm11, were resistant to NL15; consequently an appropriate change in the cultivar recommendations for use in the integrated control strategy was successfully promulgated. It is predicted that variations of this integrated control strategy involving the use of appropriately selectedDm gene combinations may prove effective for some time. This prediction is based on studies of the status of the avirulence loci in the two phenylamide insensitive pathotypes and of the specific virulence characteristics of phenylamide sensitive components of the pathogen population. 相似文献
208.
A field experiment was conducted from 1985–1986 to 2002–2003 on Vertisols under rainfed conditions to evaluate the effect of cropping systems and application of fertilizers and manure on seed cotton yield. To determine the long‐term effects, trends and stability analyses were performed. Soil samples (0–0.15 and 0.15–0.30 m) were collected at the end of year 18 and analysed for available P and AB‐DTPA extractable Zn. Among cropping systems, Asiatic diploid cotton (Gossypium arboreum) yielded 233 kg ha?1 more seed cotton than the upland tetraploid cotton (Gossypium hirsutum). Yield trend was positive for G. arboreum compared with G. hirsutum. However, the slope was not significant. Stability analyses indicated overall higher yield stability for G. arboreum than G. hirsutum. Compared with monocropping G. hirsutum, G. hirsutum–sorghum (Sorghum bicolor L.) (H‐S) rotation was significantly more stable. Soil samples (0–0.30 m) of the manure‐amended plots had significantly greater P and Zn content (above the critical limit) compared to those receiving inorganic fertilizers alone. With regard to nutrient management practices, seed cotton yield was the highest for the integrated nutrient management (INM) treatment receiving a combination of organic and inorganic fertilizers. Among primary nutrients, the effect of P was significant while that of K was not. Balanced fertilizer application was significantly better than treatments receiving N and NK. Yield trends were, in general, not significant. However, a positive trend was noticed for treatments receiving manure compared to fertilizer alone. Stability analysis, on the other hand, indicated that the slopes were, in general, significant. Among the nutrients, mean yield response with and without P was 1007 and 672 kg ha?1 respectively. Combined application of manure and fertilizer (INM) resulted in the highest mean yield response (1218 kg ha?1) and the slope was highly significant (P < 0.004). In the manure‐amended plots, a better nutrient status probably imparted a greater degree of yield stability. The present study suggests that compared to trend analysis, stability analysis being sensitive as it recognizes the treatment × environment interaction, is a better option to interpret results from long‐term agronomic experiments. 相似文献
209.
There are more than two power source in Hybrid Electrical Vehicle(HEV). By using of assist accelerating, power regeneration, Idle stop and power management, HEV gains more acceleration performance and more fuel economy and better gas emission than Conventional Vehicle(CV). With Integrated Starter and Generator(ISG) as a auxiliary power source, batteries and battery control module and power manage module as a Load leveling Device (LLD), two prototype HEV separately equipped Manual Transmission (MT) and Continuously Variable Transmission (CVT) was successfully developed. 相似文献
210.
The author analyses the advantages and disadvantages of common indirect regulation pricing methods of public utility goods. It is pointed out that it results in high trade-cost and A-J effect binging in an excess of investment when capital yield method be used. It is not reasonable enough in setting PRI-X of PRI-X pricing method. An integrated indirect regulation pricing method is put forward which is to form a two-tier incentive mechanics both in expanding producing ability and improving efficiency. In initial stages of new public project, capital yield method should be used in order to activate investment motive. Upper-limit pricing method should be used in anaphase in order to improve the producing efficiency. 相似文献