Field and laboratory observations on some tree borers and their hosts in North Sinai Governorate, Egypt.
The present investigation showed some field and laboratory observations on the borers infesting economic fruit and wood trees in North Sinai Governorate, Egypt. Studies revealed that the survival of Capnodis carbonaria beetles differed during different months, the longest survival was 48.8 days during December, while the shortest one was 12.5 days during July. Monthly relative percentage of deposited eggs per female was 7.5, 12.5, 27.5, 22.5, 19.5 and 11.1% during May to October, respectively. Batocera rufomaculata infested mango trees also. The activity period of this pest was observed from April until November. The beetles were able to attack fig, mango, sycamore [Acer pseudoplatanus] and apple with relative percentages of deposited eggs of 21.3, 31.7, 40.2 and 6.8% on previous hosts, respectively. However, peach, pear, mulberry and acacia were not suitable to infestation. The seasonal emergence of Xystrocera globosa beetles as abundant during different seasons. The emergence percentages were 9.8, 41.1, 37.3 and 11.8% for winter, spring, summer and autumn, respectively. Two peaks of emergence were observed during May and September. Monthly relative percentages of developmental stages of Steraspis squamosa [Geoica utricularia] within tamarisk [Tamarix spp.] trees showed that the immature larvae and beetles were abundant within the host throughout the whole year, the full grown larvae and pre-pupae were observed from February to November, while the pupae were found during March to December. Beetles had quiescence period within trees during winter and early spring months. The weather factors revealed positive significant effect on population of fullgrown larvae, pre-pupae and pupae, while the effect was negative significant on adult populations within trees.