In vitro and in vivo evaluation of fungicides against anthracnose disease on pomegranate (Punica granatum L.) caused by Colletotrichum gloeosporioides

Abstract

Successful cultivation of pomegranate in India has faced many challenges, with diseases and pests being the major constraints. Many pathogens affect pomegranate leaves and fruits, and anthracnose, which can cause significant damage to the pomegranate crop. The spraying of fungicides with varying modes of action is a successful disease management approach. Hence, the present work was aimed to characterize the pathogen and evaluate the different fungicides for the effective control of the disease under field conditions. The pathogen was identified as Colletotrichum gloeosporioides through morphological features and sequencing of ITS 1 and ITS 4 regions. Fifteen fungicides were then tested in vitro against C. gloeosporioides using the poison food technique at various concentrations. Out of the five contact fungicides evaluated, copper oxychloride was found to be the most effective against C. gloeosporioides. On the other hand, all three concentrations of pyraclostrobin, thiophanate methyl, tebuconazole, hexaconazole, and propiconazole showed 100 % inhibition. Among the five combination products tested, propiconazole + difenconazole, tebuconazole + trifloxystrobin, and pyraclostrobin + epoxiconazole showed 100 % inhibition. After the in vitro results, the field evaluation was further studied to find the most effective fungicides. The trifloxystrobin + tebuconazole fungicide was found to have a percent disease index of 4.50, which was significantly lower than all other treatments. The plots treated with this fungicide produced the highest yield of 10.92 t/ha, followed by Pyraclostrobin + Epoxiconazole at 9.89 t/ha. The control plot had the lowest yield, producing only 3.02 t/ha. Based on field evaluations, Tebuconazole + Trifloxystrobin is recommended as a preventative measure against anthracnose disease in pomegranates.