Effect of irrigation systems on some insect pest populations on bean (Phaseolus vulgaris L.)

In this study, the effect of three irrigation systems on the developmental of some pest populations on bean in field conditions was evaluated. In addition, temperature-dependent development and reproduction capacity of Aphis fabae Scopoli and Aphis craccivora Koch were studied in the laboratory conditions on bean (Phaseolus vulgaris L.) at different temperature. The aim of this work was to obtain the basic information about irrigation system selection in field areas, which play a fundamental role in IPM control strategies and emphasis was laid on common irrigation systems often applied on bean plantation. In total six insect pests were investigated which are Frankliniella occidentalis (Pergande) and Thrips tabaci Lindeman (Thysanoptera; Thripidae), Bemisia tabaci (Grenn) (Hemiptera; Aleyrodidae), Aphis fabae Scopoli (Hemiptera; Aphididae), Tetranychus urticae Koch (Acari: Tetranychidae), Empoasca decipiens Paoli (Hemiptera: Cicadellidae), Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) and some insect predators such as Aphidoletes aphidimyza, (Cecidomyiidae), Coccinella septempunctata (Coccinellidae), and Orius Spp (Anthocoridae). According to the results, the number of A. fabae individual per plant from Sprinkler, drip, and furrow irrigation was 36.56, 540.95, and 10.92 adults and 42.91, 130.1, and 8.17 nymphs respectively. T. urticae was 15.88, 29.85 and, 6.91 eggs and 6.91, 6.36 and, 1.88 nymphs and 1.88, 3.27 and, 0.71 adults respectively. According to the predator numbers, they were more significant on drip irrigation than other systems. However, developmental period of A. fabae was determined at 16°C (11.58 days), 24°C (5.7 days), and at 28°C (6.62 days) compared to A. craccivora at 16 °C (10.5 days) and 28°C (5.0 days). The intrinsic rate of increase (rm) was calculated at 24oC for A. fabae and A. craccivora (0.361 and 0.352 developmental rate/days, respectively). Developmental threshold of A. fabae and A. craccivora on bean were 8.14 and 1.75°C, while thermal constant temperatures were 104.16 and 66.66 degree-days on pinto bean, respectively.