Efficacy of various natural plant extracts and the synthetic insecticide cypermethrin 25EC against Leucinodes orbonalis and their impact on natural enemies in brinjal crop

• Published in: International journal of tropical insect science 2022-02, Vol.42 (1), p.173-182
• Main Authors: Ullah, Mehran, Ullah, Farman, Khan, Muhammad Anwar, Ahmad, Shakil, Jamil, Momana, Sardar, Sapna, Tariq, Kaleem, Ahmed, Nazeer
• Format: Article
• Language: English
• Subjects: Biomedical and Life Sciences; Borers; Cypermethrin; Entomology; Eucalyptus; Flowers; Fruits; Garlic; Infestation; Insecticides; Leaves; Leucinodes orbonalis; Life Sciences; Natural enemies; Neem; Neem oil; Original Research Article; Plant extracts; Population density; Shoots; Vegetable oils
• ISSN: 1742-7592; 1742-7584; 1742-7592
• DOI: 10.1007/s42690-021-00528-1

The fruit and shoot borer, Leucinodes orbonalis , is a major pest affecting brinjal production throughout the world. In this study, we investigated the efficacy of various natural plant extracts and a synthetic insecticide against L. orbonalis , and their impact on natural enemies. Eight different treatments were tested as follow: (1) neem oil at 2%, (2) neem oil at 5%, (3) Eucalyptus leaf extracts at 3%, (4) Eucalyptus leaf extracts at 6%, (5) garlic bulb extracts at 4%, (6) garlic bulb extracts at 8%, (7) cypermethrin 25 EC, and (8) untreated control. Results showed the lowest shoot and fruit infestation in cypermethrin-treated plots (2.03%), followed by neem oil (5%). The highest shoot and fruit infestation were recorded in the untreated control, followed by garlic bulb extract (4%). The highest number of flowers per plant was observed in cypermethrin-treated plots, followed by neem oil (5%), while the lowest was recorded in untreated control, followed by garlic bulb extract (4%). The highest population densities of ladybird beetle, green lacewing, and syrphid fly were recorded in the control, while the lowest densities of these natural enemies were observed in cypermethrin-treated plots. The highest yield of brinjal was recorded in cypermethrin-treated plots (3731.5 kg/ha), followed by neem oil at 5% with 3273.2 kg/ha, while the lowest yield was obtained in control plots (753.3 kg/ha). Overall, this study showed that the natural plant extracts (notably neem oil 5%) significantly reduced shoots and fruit infestation, and could, therefore, be used against L. orbonalis in the brinjal crop.