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The present work aimed to evaluate the efficiency of three insecticides [indoxacarb (Avaunt 15% EC), lufenuron (Match 5% EC) and methoxyfenozide (Runner 24% SC)] at their recommended rates at two different spray times of 10 or 15 days after the first spray against potato tuber moth (PTM), Phthorimaea operculella (Zeller) larvae on two potato varieties (Spunta and Mondial) during two successive summer seasons 2014 and 2015 at Appig village, Kafer El-zyaat center, Gharbia Governorate, Egypt. A randomized complete block design was applied for treatments including untreated check. The results showed that for 10 days experiments at season 2014, all treatments achieved reduction of PTM population in the foliage infestation when the highest values were recorded with Avaunt (46.29% & 41.97%) followed by Runner (34.84 % & 28.10 %) and Match (33.04% & 26.53%), for Spunta and Mondial varieties, respectively. The same trend was also recorded during the season of 2015. However, for 15 days experiments during season 2014, all treatments showed reduction of PTM population in the foliage infestation when the highest values were recorded with Avaunt (54.46% & 61.41%) followed by Runner (47.01 % & 47.47 %) and Match (41.18% & 44.51%), for Spunta and Mondial varieties, respectively. The same trend was also recorded at season 2015. Generally, all treatments achieved reduction of PTM population in the foliage infestation and resulted in increasing the potato yield of two varieties compared with untreated check. Fifteen days experiments were more appropriate than ten days where, Spunta variety was more susceptible to foliage infestation than Mondial variety.

The acaricidal activity of Chrozophora oblongifolia (Delile) Spreng. (Euphorbiaceae) extracts collected from Dakhla Oasis, Western Desert of Egypt was examined against larvae and adult females of Tetranychus urticae Koch (Acari: Tetranychidae). Acaricidal activity-guided isolation of methylene chloride, ethyl acetate, butanol fractions resulted in separation and identification of phydroxybenzaldehyde (1), 3,5-dimethoxy-4-hydroxybenzaldehyde (2), scopoletin (3), amentoflavone (4), apigenin 7-O-β-D-glucopyranoside (5) and apigenin 7-O-β-D-[2",6"-bis(4-hydroxy-E-cinnamoyl)] glucopyranoside (6). The isolated compounds were identified by MS and NMR spectral analyses. The susceptibility of the larvae and adult females of T. urticae Koch to the tested isolated compounds revealed that apigenin 7-O-β-D-[2",6"-bis(4-hydroxy-E-cinnamoyl)] glucopyranoside (6) and apigenin 7-O-ß-D-glucopyranoside (5) isolated from butanol fraction (most effective fraction) exhibited a high degree of acaricidal activity using leaf-dipping technique against larvae after 7-days of exposure, respectively.

Chromatographic separation of Catharanthus roseus yielded six fractions. Of the sex fractions, the alkaloid and butanol fractions were the most effective fraction against Spodoptera littoralis (Boisd.) larvae in their second instar after seven days of exposure using leaf dipping technique with LC50 value 234.58 and 481.09 ppm, respectively. Toxicological effect guided isolation and elucidation of the most toxic fraction and yielded three monoterpenoid indole alkaloids, vindoline (1), vindorosin (2) and ajmalicine (3) using extensive chromatographic and spectroscopic techniques. The effect of alkaloid and butanol fractions on biochemical aspects including transaminases enzymes (AST and ALT), acelylcolinesterase and chitinase for S. littoralis, 2 nd instar larvae were evaluated. A significant activation on AST and ALT activities were obtained after treatment with LC50 of alkaloid and butanol fractions also, both fractions might be used as AchE inhibitors and suggested an ability in biodegradation of chitin. The sublethal effect of both alkaloid and butanol fractions on the biological aspects of S. littoralis immature and adult stages were studied in details.