الفهرس 
Survey of red palm weevils in palm plantationsOnly 14 pages are availabe for public view
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Abstract
The infestation pattern of the red palm weevil (RPW) Rhynchophours ferrugineus in Eastern Part of Saudi Arabia was studied conclusively in 11000 date palm trees. The general infestation rate was 3.69%, however, this was independent of location sites, irrigation system, pruning of leaves, intercropping of plants. On the other hand, infestation rates was varied significantly according to the farm size (number of date palms/farm), the age of the tree, and the infection site (root, trunk or crown). Also, infestation levels (severity) were differed according to the surface (early),the moderate and the deep (late) infestation. Isolation and identification of Saudi entomopathogenic nematodes (EPNs) detected the existence of Heterorhabditis indica and two new steinernematid nematodes. The pathogenicity tests using LC50 and LT50 indicated that the most virulent and fastest nematode against all stages of RPW is the Egyptian H.bacteriophora followed by the Saudi H.indica then the two Saudi steinernematids. In addition, the most susceptible insect stage to EPNs was the fourth larval instar, then the eighth instar followed by the adult stage then, the cocooned pupal stage. In this content, all the isolated nematodes were easily mass-produced on the full grown larvae of Galleria mellonella. Spraying nematodes on date palm trunks and surrounding soil, under semi-field conditions, revealed that, H.indica was efficient than steinernematid in controlling adults of RPW. However, differences of insect mortality were time exposure and nematode dose dependent. Also, spraying nematodes to the leaf-petioles, under field condition, induced highly significant mortality in cocooned pupae of RPWs. This support the possi, bility of using this technique in controlling the RPW population in the beginning of spring season. Additionally, injection of the heterorhbditid nematode in the galleries of the infested trunk, succeeded in controlling the larvae of the RPW. This mortality differs according to the nematode spices isolate, the frequency of treatment and the severity symptoms. Using the EPNs in soil under the pheromone/kairomone traps caused high mortality of the visiting weevils (58.4%) that attracted under traps. This method is rather encouraging since 50% of the total weevils were attracted under the traps while the remaining weevils were captured inside it.