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391.
  1. A blend of longhorn beetle pheromones was tested as a generic attractant in a Central European oak forest. Overall, 20 cerambycid species totalling 1250 specimens were captured using two trap types.
  2. More adults of Phymatodes testaceus and Leiopus nebulosus nebulosus were attracted to pheromone-baited traps compared to solvent controls. Significant numbers of four other species were caught by panel traps but not funnel traps. For the cerambycine Pyrrhidium sanguineum, significantly more beetles were caught in treatment traps than controls. For the cerambycine Anaglyptus mysticus, lepturines Cortodera humeralis and Rhagium sycophanta, the numbers of beetles caught in treatment or control traps were similar, indicating no attraction to the lure blend. Adults of a predatory clerid beetle Clerus mutillarius were caught in significantly larger numbers by both baited trap types in comparison to controls, totalling 1514 specimens.
  3. Antennae of both sexes of C. mutillarius showed responses to 3-hydroxyhexan-2-one and 2-methylbutan-1-ol, and males also responded to syn-2,3-hexanediol.
  4. Strong attraction of C. mutillarius suggests eavesdropping on the pheromones of cerambycids and that such attractant baits, without traps, might be used to manipulate the local population density of predators in a push-pull biological control program.
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392.
Erwinia amylovora is the causative agent of fire blight, a bacterial disease existing as an unsolved problem in most countries where pome fruits like apple (Malus domestica) and pear (Pyrus communis) or ornamental plants of Rosaceae are grown. The primary site of colonization is the open flower. As for the establishment of the disease, the importance of various organs within the flowers is considerably different. The usual place for developing a large epiphytic population is the stigma. The actual infection will be attained by the external washing (rain, heavy dew) of bacteria from the stigma to the hypanthium. The bacteria penetrate through the openings of the nectary, so, the nectarthodes are the main entrance sites for them. Nectar is an excellent medium for growth of fire blight bacteria. Most often, however, the incidence of disease is significantly less than the percentage of colonized flowers. Little is known about the interrelationships of free moisture, nectar sugar concentration, ovary water potential, fine-structural characteristics of nectary versus the disease incidence and severity. The aim of this paper is to review the ecology and infection biology of Erwinia amylovora on floral surfaces and in floral tissues. Received July 8, 2002; accepted October 17, 2002 Published online: June 2, 2003  相似文献   
393.
Plasmonics - A novel numerical methodology has been developed, which makes possible to optimize arbitrary emitting dipole and plasmonic nano-resonator configuration with an arbitrary objective...  相似文献   
394.
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