Evaluation of the control of citrus nematode (Tylenchulus semipenetrans) by leaf extracts of many plants and their effects on plant growth

The citrus nematode is an important nematode that is distributed in citrus gardens worldwide and causes decline and growth reduction of citrus plants. A control way of this nematode is chemical control that it is dangerous to environment. In this research, leaf extract of Allium sativum,_ Brassica campestris, Capsicum frutescents,_Glycyrrhiza glabra,_Datura innoxia, Chenopodium botrys_and Foeniculum vulgare was used to evaluate them on plant growth and citrus nematode control in Fars province, Iran. In laboratory conditions different plant extracts, concentration of each extract and duration time of exposure extracts was examined in Petri dishes. Results showed that increase in concentration and duration time of exposure extracts caused increased percentage of nematode mortality. In laboratory experiments extracts of A. sativum and C. frutescents, D. innoxia, F. vulgare were more effective respectively. In pod experiments, nematode populations decreased in seedlings that were treated with A. sativum, C. frutescents and F. vulgare compared with control sample. In these, pods increased plant growth. These results confirm that it is possible to use local plant extracts to control citrus nematode instead of using chemical nematicides.