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梨木虱是全国性的梨树主要害虫之一 ,以若虫和成虫在叶片和新梢上危害 ,剌吸树汁。受害后的叶片主脉两侧靠叶柄处发黑 ,还可诱发煤污病 ,严重时引起提早落叶 ,果实发育不良 ,新梢受害后生长停顿、树势衰弱 ,严重影响梨子的产量和品质 ,因此应抓住关键时期进行防治。1.越冬期。清扫果园 ,清除枯枝落叶及杂草 ,刮除翘裂树皮 ,以减少越冬虫口基数。2.出蛰期。梨木虱在3月初(气温0℃以上)开始活动 ,此时虫体较虚弱。且出蛰盛期是第1代卵孵化始期 ,梨叶尚未长出 ,成虫和卵均暴露在枝条上 ,此时重点防治1~2次 ,可有效杀灭越冬成虫。常… 相似文献
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1993-1994年在莱阳梨区对第1、2世代中国梨木虱自然种群进行了系统观察,组建了2个生命表,并对影响种群数量变动的一些因素作了探讨。经生命表分析得出,该虫第1、2世代种群的趋势指数分别为4.19和3.97;世代的存活率分别为5.82%和5.52%。通过存活曲线分析得出,该虫自然种群的存活曲线属Peral(1928年)Ⅲ型曲线,这表明,种群消亡的主要阶段为生命的早期;而实验种群则为Ⅱ型曲线。经P 相似文献
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梨木虱(PsylapyrisugaForster)是鲁西北地区梨树的主要害虫之一。当地梨园多注重化学防治害虫,梨木虱的抗药性越来越强,而一些天敌遭致杀伤,使该虫为害日趋严重。因此,以天敌保护利用为主的害虫生物防治受到人们的重视。我们于1991~199... 相似文献
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中国梨木虱(Psylla chinensis)是危害梨树最严重的害虫之一,严重影响梨树的生长发育和果品产量,掌握环境因素对梨木虱生存的影响对制定有效防控策略具有重要意义.为了了解温度和水分对越冬代冬型中国梨木虱存活的影响,本研究在室内分别测定了2,10,20℃3种温度条件下,有无外源水分对梨木虱的死亡率和存活时间的影响... 相似文献
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梨木虱在我市梨区发生较普遍 ,近几年随着农村产业结构调整 ,梨树栽培面积 0 .4万 hm2 左右 ,梨木虱在梨区都有不同程度的大面积发生 ,部分受害严重的梨区被害株率达 1 0 0 % ,造成树势衰弱 ,严重影响花芽分化 ,导致减产 ,果品品质下降 ,我站就梨木虱的危害 ,发生规律与防治进行了系统研究。1 为害特点与发生规律1 .1 为害特点梨木虱食性专一 ,主要为害梨木 ,据我们从 2月中旬开始在玉泉胡井村梨园定点系统观察 ,发现越冬成虫出蛰。成虫、若虫早春及食花、芽、嫩梢、叶及幼果汁液。夏、秋多在叶背取食 ,成虫及若虫食芽、叶及嫩梢汁液 ,受… 相似文献
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梨木虱在北方梨区发生较普遍,近几年随着梨树栽培面积的不断扩大,在湖北省梨区都有大面积的发生,部分受害严重的梨园被害株率几乎100%,造成树势衰弱,影响花芽分化,导致连年减产,果品品质下降,为此,笔者在湖北省农科院果茶所就梨木虱的危害、发生规律与防治进... 相似文献
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Oviposition deterrents have the potential to prevent insect infestations in agroecosystems. In the present study, the level
and duration of this behavioral effect was evaluated against pear psylla,Cacopsylla pyri (L.) (Hemiptera: Psyllidae), a serious pest of pears in Turkey. The activity of four oily substances — cotton seed oil, fish-liver
oil, neem oil and summer oil — was tested against winterform and summerform females of the pest in laboratory and field experiments,
in order to determine their oviposition deterrency and stability as deterrents. In the laboratory assays, the initial (3 days
after treatments) deterrency of all test materials was 100%. While decreases in initial deterrency started after 1 week for
neem oil and after 2 weeks for cotton seed oil, fish-liver oil and summer oil exhibited 100% deterrent activity against winterforms,
but not summerforms during the 3-week test period. The last two also exhibited strong oviposition deterrent activity for both
forms ofC. pyri females in field trials. A significant reduction in the total number of eggs laid was observed in the field plots. Data showed
that summer oil and fish-liver oil are the most promising oviposition deterrents against pear psylla females.
http://www.phytoparasitica.org posting Sept. 28, 2004. 相似文献
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为明确中国梨喀木虱Cacopsylla chinensis越冬代(也称冬型梨木虱)在非寄主越冬植物(苹果树、桃树、樱桃树、李树、杏树、山楂树)上的适应性,于实验室内测定其在选择性条件下对不同植物组合的趋向偏好及产卵特点,并测定非选择性条件下其在不同植物上的存活、产卵以及寄主转换后的死亡情况。结果显示,在选择性条件下,当有寄主植物梨树枝条存在时,冬型梨木虱对其的趋向占比为 24.29%,而对苹果树、桃树、李树、杏树、樱桃树和山楂树枝条的趋向占比分别为 25.76%、20.81%、13.26%、8.25%、4.01%和3.62%,在梨树和苹果树枝条上的产卵量为111.00粒和7.67粒,未在其他果树枝条上产卵;当无寄主植物梨树枝条存在时,冬型梨木虱对苹果树枝条的趋向占比最高,为 35.45%,明显高于对樱桃树、杏树、桃树、山楂树和李树枝条的趋向占比,分别为 15.96%、13.19%、13.05%、12.41%和9.95%,且在苹果树、樱桃树、李树、桃树、杏树和山楂树枝条上的产卵量分别为14.25、9.75、7.25、4.75、2.75和1.00粒,总产卵量下降。在非选择性条件下,梨树枝条上冬型梨木虱的致死中时为17.11 d,在其他非寄主果树枝条上的致死中时集中在7.00~9.00 d;其在梨树枝条上的14 d累计产卵量最高,为136.67粒,而在苹果树、樱桃树、桃树、杏树、山楂树和李树枝条上的14 d累计产卵量大幅减少,分别为41.00、11.30、5.33、1.00、1.00和0.67粒,在梨树枝条上卵的孵化率为74.26%,在苹果树枝条上卵的孵化率为24.80%,在其他果树枝条上卵极少孵化。冬型梨木虱从非寄主苹果树转到寄主梨树时对其存活影响较小,第8 天累计死亡率为13.33%,相反,从寄主梨树转到非寄主苹果树上后对其存活影响明显,第8天累计死亡率达到了81.67%。表明所测试的非寄主植物均不能满足冬型梨木虱存活和子代发育所需营养,仅可作为临时替代寄主或越冬过渡寄主,非寄主植物苹果树可作为致死性诱集植物用于冬型梨木虱的防治。 相似文献
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A field trial was carried out to evaluate the efficacy of several selective insecticides for the control of pear psyllaCacopsylla pyri (L.) (Hemiptera: Psyllidae) in two successive years. Three insect growth regulators (IGRs) — diflubenzuron, pyriproxyfen
and teflubenzuron, and an amin-hydrazine derivative — amitraz, were evaluated singly and in combination with summer oil (1%).
All insecticides were applied at recommended label rates in both years. When compared with the untreated control, all insecticides
alone and their combinations with summer oil, except for pyriproxyfen alone, provided control of young (1st and 2nd instars)
nymphs. However, combined applications of these insecticides and summer oil were more effective than either insecticide alone
for controlling the egg and young nymph stages of the pest. The products were less effective against older (3rd–5th instars)
nymphs, even in combination with summer oil, and failed to suppress the population of older nymphs. Adding oil to sprays also
delayed oviposition by winterform and summerform females. With the exception of oil with amitraz, combinations of insecticides
with summer oil did not cause any phytotoxicity during the study. 相似文献
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本文采用24孔板叶片浸渍法,分别测定以水胺硫磷为主的三种混剂对梨木虱的毒力,结果显示三种混剂增效明显,其25%水胺.辛乳油,25%高渗水.硫乳油增效显著,通过应用系数分析证明二者实际应用价值较大。 相似文献