Marginal Effects of the Datura Plant (Datura starmonium L.) on Density of Key Pests of Tomato (Lycopersicon esculentum Mill.)

Fields marginal weed can be used as effective factor in dispersion and spatial distribution of pests and work as trap plants to protect the main product or can be a suitable habitat for beneficial insects as well. An investigation was conducted in one of tomato farms in Kalat-miyan village, located in Chenaran city in 2012-13 in order to evaluate the effects of marginal datura weed on the density of tomato important pests such as aphid, thrips, and heliotis. This factorial experiment was done in randomized complete blocks designed with two treatments (presence or absence of weed margins) and four different levels (the distance from the field’s margin) with three repelication. The results showed that after growing tomato plants, aphids and thrips emerged and a significant difference was observed in pest reduction between the plots with presence of marginal datura and those with no marginal datura .About the effect of Helianthis,a significant relationship was observed between the amount of heliothisdamage and presence of marginal datura plant. Since datura contains daturin toxic compounds, it will cause the repelling of suncking insects such as aphids and thrips which feed on the plant. datura had an effective role on Heliothis density. There was also a significant relationship between the distance from weed margin and the pest density so that the more the distance from weed margin, the more density of aphids and thrips and the less density of Heliothis happend. So datura plant can be used in tomato farms as integrated pest management.