Bio-efficacy of Different Plant Products against Earhead Bug (Leptocorisa spp.) on Rice (Tulaipanji) in Old Alluvial Zone, West Bengal, India
Résumé
Rice (Oryza sativa) is an important staple widely consumed in Asian countries and it is attacked by several pests. Gundhi bug or ear head bug (Leptocorisa spp) is one of the major pest of rice. Botanical is now gaining importance to manage the crop pest and protect the environment from toxic effect of pesticides causing pollution which is a global concern. So, the present study was conducted in three consecutive kharif seasons from 2017 to 2019 at Regional Research Station (Old Alluvial Zone), UBKV, Majhian, Dakshin Dinajpur, West Bengal to evaluate bio efficacy of different botanicals against rice ear head bug (Leptocorisa spp.). The experimental design was laid out in RBD (Randomized Block Design) using ten treatments and three replications. All the treatments were superior over control. The standard check treatment, Thiamethoxam (100g/ha.) was found most effective treatment in all the cases as compared to the formulated botanicals used in the studies The three years pooled mean data of kharif of rice earhead bug population and grain yield revealed that inorganic chemical treatment, Thiamethoxam (100g/ha.) was found very effective and exhibited lowest population of earhead bugs (0.90 /hill) and highest yield (28.57q/ha). Amongst the botanicals, Neem Seed Kernel extracts 5% was recorded lowest population (1.80) and highest yield (27.03 quintal/ha) over control and followed by Neem oil 1% (2.08/hill), Pongamia seed kernal extract 5% (2.14/hill), Karanja oil 1% (2.30/hill), Jathropa leaf extract 10% (2.47/hill), Custard apple leaf extract 10% (2.56/hill), Jathropa leaf extract 5%( 2.92/hill) and Custard apple leaf extract 5% (3.05/hill). The untreated control plot recorded highest population of ear head bug (6.24 /hill) and lowest grain yield (15.06 q/ha). Considering two parameter efficacy and yield, Neem Seed Kernel extracts 5% was found most effective treatment amongst the botanicals used in the studies. Botanical source of insecticides could serve as an alternative to popularly used synthetic chemical insecticides which result to reduce environmental hazards and save non-targets living beings. Botanical pesticides can supplement and easily be incorporated into Bio-intensive Integrated Pests Management Programme for the development of sustainable agriculture.