Bio-rationale Management of Tomato Leaf Miner, Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae) Using Extracts of Neem (Azadirachta indica A. Juss) Jimsonweed (Datura stramonium L) and Periwinkle (Vinca rosea L.)

Abstract

Recently, tomato leaf miner (TLM) Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), is the most notorious pest of tomato worldwide causing severe reduction of yields in both protected and open fields. In Sudan, the pest was recorded to attack all tomato cultivation areas causing considerable damage affecting income of poor farmers. Various pesticides of different active ingredients are applied excessively and routinely to control T. absoluta in tomato. As known, reliance on insecticide cause adverse impacts in human health, create insect resistance as well as affect environment and natural enemies. This study is initiated to evaluate the efficacy of extracts of 3 botanicals as alternative to synthetic insecticides against T. absoluta. A randomized Complete Block Design field experiment was conducted at Takroof experimental farm of Kassala and Gash Research Station, Sudan during season (2019/2020). The experiment consisted of Neem seed oil, water extracts of Datura, Water extract of Vinca, Dancid®; synthetic insecticide as standard, and non-treated treatment as control. Each treatment was replicated thrice Data included number of infested plants/plot, number of mines/plot, percentage of infested fruits and yield (Ton/ha) were compiled, variance among treatments (ANOVA) was statistically analyzed and means were separated using Duncan Multiple Range Test (DMRT) applying SAS 9 a computer based program. The results of this study, revealed high significant difference between treatments in the number of infested plants/plot, number of active mines/plots for the three assessment times of the post spray counts. Water extract of Datura and Neem seed oil were better than Dancid® and Vinca in reducing the number of infested plants/plots and number of active mines/plots. All test products were significantly same in reduction the percentage of infestation of fruits and they were less than the control. Also high significant difference was observed between treatments on yield. Plots treated with Neem seed oil obtained the highest yield followed by WE of Datura, Dancid®, WE of Vinca with 11.2, 9.9, 9.7, 8.8 (Tons/ha) while the un-treated plots obtained the lowest yield (3.8 Tons/ ha). For their potency, cheapness, easy processing and environmental friendly characters, Neem seed oil, WE of Datura, and WE of Vinca are recommended to be used to control T. absoluta in tomato crop. Keywords: Tuta absoluta neem seed oil, Datura, periwinkle, aqueous extracts