The effect of irrigation water type on life table parameters of Tetranychus urticae on eggplant
Paper ID : 1133-IPCA4
Hussein Sadeghi-Namaghi1, Gholamhossein Moravvej1, Behnaz Bakhshi Mohebbi *2
1Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Razavi Khorasan, Iran
2Plant Protection Department, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
With increasing global demand for freshwater for irrigation, the use of unconventional water sources including treated wastewater has become more prevalent, especially in regions with a paucity of water. The knowledge on how such type of water might affect the performance of the herbivorous pests is limited. In this study, the effect of irrigation water type consisting of groundwater and reclaimed wastewater on the eggplant macronutrients (Potassium (K), Sodium (Na), Nitrogen (N)), organic carbon (C/N), protein and chlorophyll content (a, b), as well as the demographic parameters of the two-spotted spider mite, Tetranychus urticae Koch, was investigated at 25±5 ℃,65±5% R.H. and 16L:8D photoperiod in the plant protection greenhouse compartment No.1 in a rectangular large standing cotton mosquito-net of 4*3 and 4-meter height. Using techniques such as Kjeldahl digestion method and Flame Photometric detection, we found that a significant increase ('p < 0.05') was obvious in K, Na, N, C/N, and chlorophyll a amounts in eggplants irrigated with wastewater in comparison with protein and chlorophyll b amounts. By studying the life history parameters of T. urticae, we recorded a remarkable decrease ('p < 0.05') in egg development time, Gross Reproductive Rate (GRR), Net Reproductive Rate (R0), Doubling Time (DT), and Mean Generation Time (T), although the natural rate of increase (rm) and the finite capacity for increase (λ) were significantly increased ('p < 0.05'). No noticeable statistical difference was observed among other demographic parameters. While treated wastewater is commonly perceived as beneficial for plants growth, our results suggest that it could amplify the risk via having a positive impact on the subsequent damages caused by herbivores.
treated wastewater, Tetranychus urticae Koch, demographic parameters, plants growth, herbivores performance
Status : Abstract Accepted (Oral Presentation)