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棉田杂草发生危害及防除技术概述 总被引:12,自引:3,他引:9
概述了目前我国不同棉区的杂草发生规律、分布特点和危害情况,归纳了当前棉田采用的植物检疫、人工防除、农业防除、物理防除、生物生态防除和化学防除等六种杂草防除方法,结合当前棉花生产现状提出了棉田杂草综合防治技术体系。 相似文献
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[目的]解决早熟禾草坪中禾本科杂草的防除难题。[方法]采用坪安2号、坪安3号加草坪抑制荆对早熟禾草坪中的禾本科杂草进行防除试验。[结果]坪安2号300倍液对早熟禾草坪中的禾本科杂草防除效果较好。[结论]坪安2号可有效防除早熟禾草坪中禾本科杂草,且对草坪安全,环境污染小。 相似文献
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北方春季干旱多大风,严重影响除草剂药效,因此掌握豆田杂草防除技巧对指导豆田杂草防除工作具有十分重大的现实意义.本文阐述了豆田苗前封闭除草和苗后茎叶处理的化学除草技巧,以期为农业科技人员提供防除豆田杂草的理论参考. 相似文献
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稻瘟病是最主要的世界性水稻病害,化学防治是目前最为有效的防控措施。通过室内生测和田间试验相结合的方法,测试了多个特效药剂和广谱药剂对稻瘟病的防治效果,探讨了稻瘟病的最优防治适期和穗颈瘟、稻曲病兼防的可能性。结果表明,三环唑仍然是预防穗颈瘟的特效杀菌剂,而嘧菌酯、肟菌酯·戊唑醇和嘧菌酯·苯醚甲环唑等广谱杀菌剂对叶瘟表现出更好的防控效果。始穗期是防治穗颈瘟的关键时期,在发病严重的情况下在齐穗期再施1次药是必要的。如果选用合适的药剂,破口前施药对穗颈瘟也有一定的防控作用。由于防治稻曲病的最佳施药时期是破口前,因此,一次施药兼防穗颈瘟和稻曲病是可行的。 相似文献
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P. M. Tomasula M. F. Kozempel M. J. Kurantz J. C. Craig 《American Journal of Potato Research》1992,69(9):525-536
Computer control of color development of potatoes through regulation of glucose/reducing sugar content in the blancher is demonstrated for french fry production. Color was controlled using two methods. In the first, anticipatory-feedback control was used to adjust glucose concentration in the potatoes leaving a hot-water blancher. Because the relationship between concentration and color was not defined through the mathematical model, operator intervention was required to control color. In the second, anticipatory-feedback control was combined with some simple rules for adjusting setpoints and color. Results indicate that the second scheme is preferable because it eliminates operator intervention to effect color control. 相似文献
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菌克毒克防治大豆根腐病药效研究 总被引:1,自引:0,他引:1
为验证生物农药-菌克毒克防治大豆根腐病的效果,用不同浓度的菌克毒克和多菌灵对大豆根腐病进行防治试验,结果表明,菌克毒克拌种剂量为1.0%~2.0%时,防效为69.1%~74.3%,增产14.1%~16.3%;多菌灵防效为45.9%,增产6.3%.菌克毒克的防病及增产效果均明显好于多菌灵. 相似文献
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Han Jo Bae Youn-Sung Kim Soon-Yong Chun Un-Ho Ji Mu Han Kim Sung Soo Han 《Fibers and Polymers》2008,9(3):323-327
High regularity is important in manufacturing spun yarn. Among controllers used in regularity control, existing PID controller
is suitable for linear time-invariant systems but not for the control of sliver draft systems with non-linear characteristic.
Thus, the present study designed a knowledge-based fuzzy controller in consideration of disturbance and non-linear characteristic
of sliver draft systems. RLS (Recursive Least Squares) was used as an estimation algorithm to formulate a model used in computer
simulation for implementing the controller, and real time estimation was made using real data from draft systems to get a
model close to actual systems. This research used a estimation model in designing a knowledge-based controller that minimizes
the variation of control response to the sliver linear density of the system, and the result of linear density control was
used to prove the superiority of the controller in control performance through CV%. 相似文献
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选择合适的防治药剂和防治次数是减轻稻曲病危害的关键。本研究以籼粳杂交稻甬优12为材料,比较了6种药剂和3种喷施次数对稻曲病的防控效果和产量性状差异。结果表明,在6种药剂中,阿米妙收处理的病穗率防效和病指防效最好,分别达到91.53%和96.63%,但与其他药剂无显著性差异。在防治次数上,爱苗和拿敌稳均为防治3次的处理病指防效最好,分别为81.73%和80.15%,显著高于防治次数3次以下的处理。阿米妙收处理的产量最高,达11 719.52 kg/hm~2,显著高于其他处理。 相似文献
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优化施肥量控制马铃薯早疫病的发生 总被引:1,自引:0,他引:1
马铃薯早疫病是一种常见的马铃薯病害,采用农艺措施控制病害的发生是一举多得的好办法。本试验通过施肥处理控制早疫病危害试验,结果表明,马铃薯早疫病发生早晚与施肥多少直接相关,施用60 kg/667m2和40 kg/667m2马铃薯复合肥,对早疫病防治效果为93.39%和88.56%,增产26.61%和22.18%,纯增效益405元/667m2和365元/667m2。因此,施40~60 kg/667m2马铃薯复合肥可以作为防治马铃薯早疫病发生的一项农业措施进行应用。 相似文献
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This series of paper addressed the quality control of a vertical-type cross-lapper machine, which is used to produce uniform
layers of fibers with suitable widths and thicknesses. The nonlinear model of the system was derived, and the corresponding
state space representation was obtained. The linearized model based on the equilibrium position of the nonlinear model was
generated, and the associated control property was analyzed. The high order linearized model would be reduced to a verified
lower order model for control system design. The designed traditional and modern controller could make the crosslapper machine
for good card web quality control. 相似文献
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野燕麦是马铃薯田的主要杂草之一,人工除草工作量大。本研究的目的是明确240 g/L收乐通EC在青海省马铃薯田防除野燕麦药效、适宜剂量及对作物的安全性。在田间使用了240 g/L收乐通EC制剂量300,450,600 mL/hm2,以108 g/L高效盖草能EC制剂量375 mL/hm2为对照药,设空白对照处理,于马铃薯3~5叶期,野燕麦为3~6叶期兑水300 L/hm2喷雾处理。结果表明,240 g/L收乐通EC是马铃薯田防除野燕麦的优良除草剂,适宜剂量为450 mL/hm2,对野燕麦40 d株防效和鲜重效均达85%以上,对马铃薯安全,增产率达10%以上。 相似文献