【摘 要】
：
魏县大葱连年暴发甜菜夜蛾魏县种植大葱已有多年历史，每年种植７００～１０００ｈｍ２，主要害虫是蓟马、潜叶蝇，从未发生过甜菜夜蛾为害。１９９３～１９９５年，甜菜夜蛾在大葱田连年暴发，为魏县大葱上的危险性害虫。８～９月份，如
论文部分内容阅读
魏县大葱连年暴发甜菜夜蛾魏县种植大葱已有多年历史，每年种植７００～１０００ｈｍ２，主要害虫是蓟马、潜叶蝇，从未发生过甜菜夜蛾为害。１９９３～１９９５年，甜菜夜蛾在大葱田连年暴发，为魏县大葱上的危险性害虫。８～９月份，如果防治不及时，大葱叶片可全部被吃...
Weixian green onions outbreak consecutive years of beet armyworms Weixian planting green onions have been for many years, each year planted 700 ~ 1000hm2, the main pests are thrips, leaf miner, never had Beet armyworm damage. From 1993 to 1995, beet armyworm outbreaks in the scallion field year after year for Wei County scallions on the dangerous pests. 8 ~ September, if the control is not timely, all the leaves can be eaten onions ...
其他文献
Due to the drawbacks in Support Vector Machine(SVM)parameter optimization,an Improved Shuffled Frog Leaping Algorithm(Im-SFLA)was proposed,and the learning abil
“洪深先生的熟情、勇敢,阴切民族团家的命莲,在同峙代的文化工作者中,可以能是最粱能可查的一个。”“洪深先生的作品是雅俗共赏,洪深先生的焉人是清周兼容。”——夏衍能
《水浒传》所以能家喻户晓、历久不衰的秘诀之一是占全书极大比重的武打描写,使外行看出热闹,内行品出门道。
“Outlaws of the Marsh” so it can be known to all, one o
冻融循环作用是砂岩风化的重要影响因素,研究冻融循环条件下砂岩的变形破坏规律对寒区岩石文物保护具有重要意义.对不同含水状态含层理及完整砂岩展开冻融循环试验,研究冻融
黄杉素是一种重要的黄酮类化合物,具有抗炎症、抗氧化等功效,在医药及保健品行业有着广泛的应用.黄酮3-羟化酶(Flavanone 3-hydroxylase,F3H)可以催化圣草酚合成黄杉素等3位
Higher order numerical schemes for stochastic differential equations (SODEs) can be derived systematically using stochastic Taylor expansions based on itera