Management of root-knot nematode Meloidogyne incognita infesting turmeric (Curcuma longa) under coconut (Cocos nucifera) cropping system

Abstract

Field experiments were conducted during 2018–19, 2019–20 and 2020–21 at ICAR-Central Plantation Crops Research Institute, Kasaragod, Kerala for assessment of biocontrol fungi for the management of root-knot nematode (RKN), Meloidogyne incognita damaging turmeric (Cucuma longa L.) (cv. IISR-Prathibha) under coconut (Cocos nucifera L.) cropping system. Treatments included talc-based formulations of Trichoderma harzianum (ICAR- Indian Institute of Spices Research (IISR), Kerala and ICAR-Central Plantation Crops Research Institute (CPCRI), Kerala isolates) and Pochonia chlamydosporia (ICAR-Indian Institute of Spices Research, Kerala isolate), neem cake, marigold and carbosulfan 25 ec (standard check). Talc-based formulations were applied at 50 g/bed, neem cake @1 kg/bed at pre-monsoon and post-monsoon, marigold @30 plants/bed compared with untreated and standard check carbosulfan 25 ec @5 litre/bed at pre-monsoon and post-monsoon against M. incognita. Maximum reduction of RKN in the soil, as well as root, was achieved by either P. chlamydosporia (74 and 86%, respectively) or carbosulfan (67 and 87%, respectively) over the control. A number of the tillers (3.75/plant) for P. chlamydosporia and (3.23/ plant) for carbosulfan were recorded more in comparison to control (1.42/plant). The findings demonstrated that P. chlamydosporia (ICAR-Indian Institute of Spices Research) is a promising alternative to synthetic nematicides for the management of M. incognita due to its high antagonistic and good plant growth promotion activities. However, large scale field trials on these promising fungal biocontrol agents can be considered for evaluation in relation to the management of RKN under field conditions for confirmation.