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Abstract:The role of bruchid beetle infestation on seed germination of Acacia tortilis (Forssk.) Hayne) Mimosaceae under different incubation temperatures and degrees of scarification was studied under controlled conditions. Results indicate that seed germination was highest (96%) in scarified seeds at 25-35ºC incubation temperature, whereas, it was only 28% in intact seeds. Seeds infected by bruchid beetles with one or two holes did not germinate regardless of different incubation temperatures. X-ray results of A. tortilis seeds showed substantial consumption of endosperm and embryonic portions by the bruchid beetles resulting in one or two holes in the infected seeds curtailing seed germination. A unique method of identifying seed viability of A. tortilis by X-ray studies is reported.

This study was conducted during 2010 and 2011 to investigate the effect of preharvest sprays on yield, harvest date, harvest period and fruit physico-chemical quality characteristics at commercial harvest date of Sokary date palm growing in Riyadh area, Saudi Arabia. These palms were sprayed at hababouk and khalal stages with naphthalene acetic acid (NAA), gibberellic acid (GA 3 ), cytofex (CPPU), putrescine (Put), salicylic acid (SA) or ethyphon (Eth). The results showed that the yield components and fruit physical characteristics (except ground color) were improved by all sprayed bioregulators, especially NAA, GA 3 and CPPU. The applications of bioregulators delayed harvest date in comparison with the control and Eth treatments. The latest harvest date was obtained with NAA followed by GA 3 and CPPU treatments. On the other hand, Eth advanced fruit ripening date in comparison with the control. All the bioregulator treatments decreased the harvest period and the percentage of unmarketable fruits. It also delayed fruit carotenoids pigment formation, but increased fruit acidity and chlorophyll content as compared with control and Eth treatments. Fruit TSS and sugar content at rutab stage were higher compared to the control. However, at tamar stage, fruit acidity was decreased by all treatments.

The life cycle of Steatoda triangulosa Walckenaer (1802), belonging to family Theridiidae, was studied in laboratory. It had 6 and 5 spiderling instars before adulthood for female and male respectively. Various instars reared on the cotton aphid, Aphis gossypii, vinegar fly, Dorsophila melanogaster, two-spotted spider mite, Tetranychus urticae, stored grain moth, Ephestia kuhniella, and larva of the Cotton leaf worm Spodoptera littoralis. Prey consumption was calculated for different stages. Mating behavior was also described.

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