Evaluation of Achook (Azadirachtin 1500ppm) against root knot nematode (Meloidogyne incognita) infecting okra

Abstract

Evaluation of different doses of Achook (1500 ppm azadirachtin EC) against Meloidogyne incognita (RKNâ€Mi) infecting okra (Abelmoschus esculentus Moench.) was undertaken under net house and openâ€field conditions. Results of pot (10cm dia) experiment showed that soil drenching of Achook and Achook A1 (contains sesame oil) at higher dosage (≥10litre/ha) showed reduced root galling, greater suppression of final soil nematode (J2) population and increased shoot height of okra. The single drenching of Achook andAchook A1 at 5 litre/ha at 15 days after sowing (DAS) immediately after appearance of first gall was also quite effective for managing the RKNâ€Mi on okra. Results from openâ€field testing of Achook EC showed efficacy to control RKNâ€Mi. The Achook and Achook A1 formulations at 5 litre/ha as single application after with the appearance of first gall was found to be most effective for reduction of root galling, soil nematode population (63 to 67%), increasing shoot height and improving (20 to 23%) fruit yield of okra. Further, at all dosages both formulations showed nematode control efficacy and enhancement of crop yield. The Achook A1 was found to be more effective (38%more yield) than soil application of carbofuran 2kg a.i./ha and neem cake at 1000kg/ha. Considering incremental cost benefit ratio (ICBR), the Achook (ICBR~4.23) and Achook1 (ICBR~4.03) at 5 litre/ha as a single soil drench with the appearance of root galling in okra was found to be the most economical. This was followed by Achook1 at 2.5 litre /ha as soil drench twice (7 DAS and 30 days after first drench) and Achook A1 5litre and 10litre/ha. The Achook A1 was found to be relatively more effective than that of carbofuran at 2kg a.i./ha and neem cake at 1000kg/ha.