Effect of Two Egyptian Cotton Varieties on Development and Life Table of the Two-Spotted Spider Mite, Tetranychus urticae Koch (Acari: Tetranychidae) in Relation to Leaf Chemical Contents

Document Type : Original Article

Authors

Department of Cotton and Field Crops Mites, Plant Protection Research Institute, Agricultural research Center, Nadi El-Said St., Dokki, Giza, 12311 Cairo, Egypt

Abstract

The development and life table of the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) were studied when reared on two Egyptian cotton varieties: Giza 86 and Giza 90 at laboratory conditions of 27±2°C and 60±5% R.H. Results cleared that the development of T. urticae female was significantly affected by cotton variety.  Immatures developmental time was shorter on Giza 90 (3.82 days) than Giza 86 (9.86 days). The adult female longevity averaged 12.29 and 16.65 days on Giza 90 and Giza 86, respectively. In addition, the values of Net reproductive rate (Ro), Intrinsic rate of natural increase (rm) and Finite rate of increase per day (λ) of T. urticae were (65.04, 0.407 and 1.502 days) and (31.95, 0.184 and 1.202 days) on Giza 90 and Giza 86, respectively. The female fecundity recorded 98.63 and 71.00 eggs / female on Giza 90 and Giza 86, respectively. The mean generation time (T) and generation doubling time (DT) values were the lowest on Giza 90 (10.27, 1.702 days) than Giza 86 (18.82, 3.766 days), respectively. A positive significant correlation was recorded between development, fecundity of T. urticae female and availability leaf nitrogen content.

Keywords

Files

Share

How to cite

Statistics