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651.
GARRY W. LEVOT 《Medical and veterinary entomology》1992,6(2):131-134
Manual application of aqueous solutions of malathion, carbaryl and permethrin controlled northern fowl mite, Ornithonyssus sylviarum Canestrini and Fanzago, on caged layer hens for at least 118 days. Azamethiphos sprayed manually provided acceptable control for a shorter period. Machine application, particularly of azamethiphos, but also malathion, provided lesser control. The addition of surfactant increased the wetting ability of the sprays but interfered with the efficacy of azamethiphos. 相似文献
652.
A new software for measuring leaf area, and area damaged by Tetranychus urticae Koch 总被引:1,自引:0,他引:1
E. M. Bakr 《Journal of Applied Entomology》2005,129(3):173-175
Abstract: Measuring leaf area manually is a tedious and time-consuming process and it is inaccurate. In an attempt to make this process easier and more accurate, a new software namely 'Compu Eye, Leaf & Symptom Area' was developed. A standard green shape with a known area of 1.5 cm2 was used to evaluate the accuracy of the software. The measurements obtained were of high accuracy. Measurements varied between 1.4771 and 1.5095 cm2 . Probabilities of t values were usually <0.01 and did not exceed 0.023. It was also observed that accuracy could be enhanced either by increasing scanner resolution and/or by decreasing measurement unit area. In order to evaluate the performance of the software, leaves with symptoms of mite injury were collected from six different plant species (squash, cucumber, green bean, vigna, dahlia and rose). Symptom area of each leaf was assessed manually and by the software. It was observed that the software was able to assess the symptom area accurately with no significant difference compared with manual measurement. 相似文献
653.
The damage of Oligonychus perseae Tuttle, Baker and Abbatiello on 'Hass' avocado trees occurs mainly on the underside of the leaves along the midrib, main veins and leaf depressions. The lower epidermal, spongy parenchyma and palisade parenchyma cells of the leaf tissues are destroyed. Large necrotic areas on the underside of the leaves result from feeding when high population levels occur. Feeding and reproduction takes place in 'nests' of silken webbing, which also provide protection from some predator mites and other natural enemies. Oligonychus perseae shows a modification of the earlier defined life-type web nest (WN-c). The greatest number of nests built by a female was 12.17 at 20°C and the greatest number of eggs per female per nest was 5.20 at 25°C. 相似文献
654.
P. W. JOHNSON 《Medical and veterinary entomology》1996,10(2):121-128
Abstract. A group of thirty-two Merino sheep infested with itch mites (Psorergates ovis) and fed a maintenance diet which imposed moderate nutritional stress had a significantly higher mite population, significantly more skin scurf, and significantly more fleece damage or derangement (P < 0.05) than a second group of thirty-two infested sheep fed a diet designed for unrestricted body weight gain and wool growth. Histologically there were no significant differences between the groups in the numbers of mast cells, neutrophils or eosinophils observed in skin sections, but sheep that had high mite counts (>10 per 200 cm2 of skin area) in both groups, had more dermal mast cells than sheep with fewer mites irrespective of the plane of nutrition. Skin thickness and greasy fleece weight in die group maintained on the low plane of nutrition were significantly less (P < 0.05) than in die well-nourished group, reflecting the difference in protein and energy content of the two diets. Within the nutritionally stressed group, the sheep with low mite counts had a significantly lower (P < 0.05) greasy fleece weight and a shorter mean staple length than the sheep with high mite counts. There was no significant difference in greasy fleece weight between sheep with low or high mite counts in the group fed on the high plane of nutrition. 相似文献
655.
Lucie M. Evans Deborah A. Dawson Richard Wall Terry Burke Jamie Stevens 《Molecular ecology resources》2003,3(3):420-424
Nine microsatellite markers have been isolated from the scab mite, Psoroptes ovis. These markers have been tested for polymorphism in individual Psoroptes mites originating from two hosts, the European rabbit, Oryctolagus cuniculus, and sheep, Ovis aries. No definitive picture of Psoroptes species’ status or interrelationships exists. This study provides the basis for a new molecular system to elucidate the systematics of groupings within the genus Psoroptes, allowing us to clarify the population dynamics and epidemiology of the mites causing sheep scab world wide. 相似文献
656.
腐食酪螨、粉尘螨传播霉菌的实验研究 总被引:14,自引:0,他引:14
探讨粉满能否携带、传播霉菌,对腐食酪螨(Tyrophagus putrescentiae)和粉尘螨(Dermatophagoides farinae)传播5种霉菌进行实验观察,并对自然环境中分离出的腐食酪螨和粉尘螨进行霉菌培养。结果表明,无论是实验条件下,还是自然情况下,腐食酪螨和粉尘螨均可携带、传播霉菌,两者无明显差异(p>0.05),且腐食酪螨和粉尘螨携带、传播霉菌不受其种类的影响。因此认为粉螨是携带、传播霉菌的重要媒介之一,应积极控制粉螨孳生,减少粉螨和霉菌对人类的危害。 相似文献