Effect of Neem Seeds Ethanolic Extracts on Mortality of Tomato leaf-miner Tuta absoluta (Lepidoptera: Gelechiidae)

Abstract

The survey data showed that there was significant difference between mean population of Tuta absoluta from the three areas Elselate, Abu Halima and Wad Elnaaeem in Khartoum State during July, August and September (2013). The population in July and August was significantly higher than September. The population in Elselat and Abu Halima was significantly higher than Wad Elnaaeem. Laboratory experiments were conducted at College of Agricultural Studies of Sudan University of Science and Technology to evaluate the lethal effect of neem seeds Azadirachta indica ethanolic extracts on the third larval instars of tomato leafminer Tuta absoluta. Five concentrations of neem seeds ethanolic extract (15%, 7.5%, 3.75%, 1.8% and 0.9) were used in this study. The highest concentration used in this study (15%) gave the higher mortality percentage of (93.3) after 72h of exposure that significantly different compared with other concentrations. However, it was not significantly different from the recommended dose of Spinosad. The probit analysis showed that the LC50 values for seeds ethanolic extracts of neem were 16.3 %, 9.7% and 3.2% after 24, 48 and 72 hrs respectively.