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101.
Caraway (Carum carvi L.) belongs to the traditional crops which have been grown in Bohemia since the end of the 19th century. Depressaria daucella (Denis and Schiffermüller) and Aceria carvi Nal. are two main pests of caraway in the Czech Republic. The latter becomes a serious problem in major caraway-growing areas. So far, no effective method for its control is known. The aim of this paper is to describe the phenology of symptoms of A. carvi infestation and damage caused by this pest. Our observation revealed that although A. carvi overwinters hidden within leaves of young caraway plants, the first symptoms are usually not visible before the start of flowering. Though the initial density of the pest is low, the mite population multiplies during the season when the pest attacks plant tissues and causes development of galls on leaves and flowers. Comparison of healthy plants and plants infested by A. carvi showed that infested plants had significantly more umbels but produced far fewer seeds, and the yield of caraway was thus substantially decreased. Recommendations for crop management methods to suppress the pest are given.Electronic Supplementary Material Supplementary material is available for this article at  相似文献   
102.
以河南省虞城县、获加县和灵宝县棉田朱砂叶螨种群动态数据和气象资料为建模材料,通过逐步回归分析分别组建了雌成螨、幼若螨和卵的预报模型。利用该模型对太康县和郑州市棉田朱砂叶螨种群动态进行了模拟,结果表明,该模型具有较高的准确度  相似文献   
103.
The poultry red mite (Dermanyssus gallinae) is a serious problem for the poultry industry worldwide. However, the relationship between the mite population and the damage that they cause is still unclear. In this study, the mite population in poultry houses was examined using an established trap method, and the risk of blood‐stained eggs caused by the mites was assessed. Traps were placed once a week outside the egg channels and/or on the floor in two poultry farms in Fukuoka Prefecture, Japan, from April 2012 to July 2014. The numbers of blood‐stained eggs and total eggs were counted at weekly intervals. The results showed that the number of mites increased from April to May, and reached a peak around the beginning of June when the average temperature and humidity were >24°C and 70–90%, respectively. In the segmented model, the correlation between the proportion of blood‐stained eggs and the number of mites or temperature was positive over a threshold. In conclusion, our established trap method is useful for monitoring mites and can be used to predict when poultry farms should be treated to prevent appearance of blood‐stained eggs.  相似文献   
104.
通过在曲阜孔林地区选择四种典型生境作为采集样点,定时定量采集土样,共分离获得标本8934号,经鉴定发现所采集标本隶属21科33属45种,其中含有16种中国新记录种。对鉴定出的45种甲螨进行区系分析表明,该地区土壤甲螨在世界动物地理区划中的分布,可以划分为8个区系型。在中国动物地理区划中可划分11种区系型。其群落分析表明:No-thrus asiaticus Aoki et ohnishi、Erembelba foliata Foliata hummer、Zygoribatula hailongensis、Ceratozetes japonicus Aoki、Scheloribates latipes为该地区的优势类群。多样性分析表明C样地多样性指数最高。  相似文献   
105.
106.
戴轩 《贵州农业科学》2008,36(1):136-138
对贵州东北低山丘陵山区茶园土壤螨类进行了调查,共获标本4 253头,隶属4个亚目。其中隐气门类占个体总数的63%,分属38科。土壤螨类平均密度为1 833.4 ind/m2。土层(0~20 cm)的螨类优势类群Schelorbates latipes,Ros-trozetes ovulum,占土层螨类27.43%。凋落物层(L层)的优势类群S.latipes,Galumna curvum,Oribatella meridionalisBer-lese,R.ovulum,共占L层的42.73%。土壤螨类在L层和表土层(0~5 cm)所占整个土壤螨类的87.73%。一年中以3~5月和9~12月份出现较多。土壤螨类栖息层次出现较强的表聚性,冬季也不减弱。  相似文献   
107.
The ovicides clofentezine and hexythiazox were shown to be compatible with integrated control of European red mite, Panonychus ulmi (Koch), in a replicated field trial conducted over two growing seasons in an apple orchard at Batlow, New South Wales, Australia. Reduced concentrations of clofentezine (5 and 10 g a.i. per 100 litres water—normally 20 g) applied as foliar sprays to run-off, stabilized the predator/prey interaction between P. ulmi and Typhlodromus pyri Scheuten more effectively than low rates of cyhexatin (5 and 10 g a.i. per 100 litres water—normally 20 g). There was no evidence that the effectiveness of clofentezine or hexythiazox would destablize integrated control by eliminating P. ulmi and starving T. pyri. Populations of T. pyri persisted in low numbers on the trees in the absence of P. ulmi or other arthropod food sources on leaves.  相似文献   
108.
在人为控制和创造有利于玉米红蜘蛛发生、又能基本满足玉米正常生长发育需要的条件下,以来自国内外的74个重要玉米自交系为材料,进行了玉米自交系对红蜘蛛抗性的人工诱发鉴定。结果表明:不同的玉米自交系对红蜘蛛的抗性差异很大,其受害指数为0.06~0.91;叶片平均受害面积百分率与受害指数呈极显著正相关(r=0.97,P0.000 01)。这些自交系以其受害指数为基础,通过聚类分析划分为高抗、抗、中感、感和高感5个类群;自交系受害指数在类群间[高抗(0.11±0.02),抗(0.22±0.04),中感(0.35±0.03),感(0.49±0.05),高感(0.75±0.10)]差异极显著(P0.01)。在参试自交系中,ZH4改-1、BSSSS53-B、Q381等20个高抗红蜘蛛,KS2564、B47、1028S等19个抗红蜘蛛,掖478、冀35、PH6WC等18个中感红蜘蛛,郑58、B73、丹340等12个感红蜘蛛,昌7-2、B107、SK59、GNS12059和Mo17-476等5个高感红蜘蛛,其中,Mo17-476对红蜘蛛表现为易感。  相似文献   
109.
Summary The bitter cucumber variety Improved Long Green did not differ in resistance to the twospotted spider mite from its near isogenic non-bitter mutant, the source of all non-bitter varieties. Four pairs of near isogenic bitter and non-bitter varieties gave similar results. Therefore any causal relation between bitterness and resistance is denied.  相似文献   
110.
为了研究山羊痒螨病对机体氧自由基及抗氧化系统的影响,分别对感染山羊和健康山羊GSH-Px、T-SOD、CAT的活力和MDA、LPO的含量进行了测定。试验结果显示,感染组山羊血清中GSH-Px活力极显著低于对照组(P<0.01),T-SOD活力极显著低于对照组(P<0.01),MDA含量显著高于对照组(P<0.05),LPO含量极显著高于对照组(P<0.01);感染组与对照组CAT活力差异不显著。试验结果表明,山羊患痒螨病后,体内氧自由基含量升高,抗氧化酶活力降低,脂质过氧化物含量上升。  相似文献   
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