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为分析棉花早衰的原因及表现、总结棉花高产栽培经验,对2014年河北威县3块早衰棉田的土壤养分状况、棉花生长情况和产量进行调查分析。分析表明:棉田起土、复耕棉田由于起土或持续失耕造成土壤氮磷钾和有机质等养分含量明显降低导致棉花早衰;前茬为苜蓿的棉田由于苜蓿的固氮作用,土壤氮磷钾和有机质等养分含量明显增加,能够减缓棉花早衰的发生。棉花早衰在冠层上表现为株高降低、棉株变细、叶绿素含量降低、果节数减少和最长果枝长度减小等方面,根系上表现为主根长和最长侧根长度变短、侧根数目变少,与相应对照棉田相比,本调查早衰棉田棉花主根长度和最长侧根长度分别降低9.7%和31%,一级侧根数减少36.4%。早衰棉花产量明显降低,主要原因是早衰棉花单株成铃数和铃重降低,起土棉田、复耕棉田和前茬棉花棉田棉花理论产量与相应对照棉田相比分别低29.3%,13.2%和4.3%。本调查说明土壤养分状况变差是造成棉花早衰的主要原因,棉田持续耕作可能造成棉花早衰。 相似文献
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近年来,45团大力推广棉花膜下滴灌技术,由于栽培方式的改变,棉田生态小气候也发生了变化,也使棉叶螨的发生、消长规律发生了变化,表现为发生早、发生量大、对棉田危害加重的趋势。通过近几年的调查和实践,提出滴灌棉田棉叶螨的发生特点、危害加重原因与防治措施。1棉叶螨生活史 相似文献
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棉铃虫性诱剂的应用方法 总被引:1,自引:1,他引:0
近几年,北疆广大棉区由于耕种和灌溉制度发生了较大的变化,秋翻冬灌被多种耕作方式所替代,如加压滴灌、干播湿出等.棉田生态系统也随之发生了较大的变化,给病虫害的防治带来了一定困难。其中,棉铃虫的危害直接影响棉花单产的提高和生产效益。近年来本地区推广棉铃虫性诱剂对棉铃虫危害起到了一定的防治效果。现将具体做法总结如下: 相似文献
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《玉米科学》2001,9(1)
苏 俊 (SuJun)研究员 ,1 956年 5月生 ,黑龙江省鸡东县人 ,汉族 ,中共党员 ,1 973年 3月下乡插队 ,1 977~ 1 982年就读于东北农业大学农学系 ,获农学学士 ;后就读于哈尔滨师范大学 ,植物遗传硕士研究生毕业。1 985~ 1 986年在南京农业部科技人员英语培训班学习一年 ,1 987年去南斯拉夫哲盟玉米所学习。 1 982~ 1 998年先后在黑龙江省农业科学院作物育种研究所和玉米研究中心工作。 1 999年后任黑龙江省农科院副院长、研究员 ,黑龙江省第九届青联副主席。主要学术任职有黑龙江省科学技术经济顾问委员会委员、黑龙江省农业科学院学术… 相似文献
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《玉米科学》2000,8(4)
郭海鳌 (GuoHaiao) ,男 ,1 94 1年 1 0月 2 5日生 ,辽宁省黑山县人、汉族 ,1 96 6年毕业于沈阳农学院遗传育种专业。现任中国北方农作物优良品种开发中心首席专家、研究员 ,东北农业大学客座教授、沈阳农业大学兼职教授、吉林省作物学会副理事长。郭海鳌高校毕业后曾在县良种场、乡农业站工作 ,1 973年后调到四平市农科所从事玉米育种研究。自 1 976年主持玉米育种课题以来 ,“六五”期间育成玉米杂交种四单 8号。四单 8号以高产、抗病、适应性广、制种产量高等优点先后通过吉、黑、内蒙和国家的审定 ,累计种植面积达 1亿亩以上 ,特… 相似文献
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Summary In many seed potato producing areas, micro- and minitubers are too small for direct planting as seed tubers in the field.
Such use of these propagules can, however, be feasible if the crop's growth and development can be advanced. Increasing light
interception, harvest index and yield of useable progeny tubers has been proved possible with plastic mulch and pre-planting
of small tubers in a greenhouse. High amounts of nitrogen (up to 180 kg ha−1) or deep planting (up to 9 cm) were less effective. Using older or pre-sprouted micro- or minitubers may be beneficial, because
this might increase the number of sprouts per mother tuber (and thus stems per plant) or advance the growth of sprouts or
stems. However, this would require even more careful management, due to the weakness of these sprouts and stems. Micro- and
minitubers should be as large as feasible when used for direct planting in the field. 相似文献
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The growth and yield in the field of two cultivars of potatoes originating from three different propagation sources — tubers, microcultured shoots (microcuttings) and small tubers produced in culture (microtubers) — were analyzed. Plants originating from microculture produced only single stems emerging from the soil surface whereas tubers formed multistemmed plants. Due to vigorous branching on microcultured plants, however, vine growth appeared similar. Although the total tuber yields were the same for plants from all three propagation sources, in general microcultured plants produced smaller-sized but a greater number of tubers. Microculture is a promising method of producing high quality, certified propagules for potato production. 相似文献
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Improvement of paddy field drainage for mechanization 总被引:1,自引:1,他引:1
In Japan, land consolidation and drainage improvement for farm mechanization in paddy fields began during the 1960 s. It was not easy to use big machines in the muddy conditions caused by the clayey soil and heavy rainfall during the harvesting period. A number of investigations were carried out by many researchers, and factors relating to drainage were clarified. Not only surface drainage but also underdrainage was planned. However, drainage was not always sufficient, because the clayey surface soil was impermeable to ponding water. It became clear that underdrainage for a clayey paddy field for the harvest is quite different from underdrainage for an ordinary field. Field and soil characteristics, as well as water conditions, should be examined carefully before planning drainage improvement for farm mechanization.Dr. Toshio Tabuchi is an honorable member of the Japanese Society of Irrigation, Drainage and Reclamation Engineering (JSIDRE), a former Professor of the University of Tokyo, and a former President of JSIDRE 相似文献