Efficacy of Plant Oils and Insecticide for Controlling Tetranychus urticae Koch as Influenced by Onion Intercropping with Tomato

Abstract

The present work was carried out at the experimental farm of Sakha Agricultural Research Station, Kafr El-Sheikh Governorate (310 07ˉ N Latitude and 300 57ˉ E longitude with an elevation of about 6 meters above sea level), Egypt in 2020/2021 and 2021/2022 seasons. The aim of the present work was to evaluate some compounds (Ethion, chamomile oil, Chamomilla recutita L. and black cumin oil, Nigella
sativa L.) against Tetranychaus urticae Koch (Acarina: Tetranychidae) on tomato (Lycopersicon esculentum Mill.) Intercropped with onion. Three intercropping systems (tomato sole, one row, two rows and three rows at the top of the ridge and onion sole). These compounds were tested for toxicity of T.urticae under laboratory and field conditions using leaf dipping and spray methods, respectively. Ethion was the most effective (R = 83.3 and 67.6) in the first and second seasons, respectively, while chamomile and black cumin oils were least toxic with R% value of 24.5% and 34.8% respectively during the first and the second seasons, respectively. The laboratory tests took a similar trend. Chamomile and black cumin oils had a less toxic effect on egg deposition, % hatchability and sterility compared to Ethion. The intercropping system (one row of onion) with tomato produced the highest yield and yield attributes except plant height. The highest LER (land equivalent ratio; 1.71 and 1.69) and the highest total income (135530 and 187035 L.E.) were obtained with Ethion treatment when tomato intercropping with one row of onion at the top of tomato ridge of two seasons, which seems to be the appropriate suggestion for farmers in North and Middle Nile Delta region, Egypt.