Integrated management of dry root rot of Arachis hypogaea caused by Rhizoctonia bataticola

Abstract

Groundnut a principal vegetable oilseed crop in India with about 85 percent area under rainfed conditions is prone to dry root rot causing considerable loss in the yield when left unmanaged. In order to find out an effective method of managing the disease, an experiment was conducted at Regional Agricultural Research Station, Tirupati during kharif 2019–20 as an integrated approach by combining the use of bio agents, organic amendments and fungicides. Native bacterial and fungal bio agents along with commercial formulations of Pseudomonas flourescens and T. harzianum, oil cakes and different fungicides were screened and tested for their efficacy against the pathogen under in vitro and field conditions. Experiment was laid out with the best performing bio agent, organic amendment and fungicide using single and combination treatments. Results revealed that, seed treatment with mancozeb @ 3g/kg and with commercial formulation of T. harzianum @ 5g/kg seed along with soil application of karanj cake @ 1.3 t/ha maintained its superiority over other treatments by recording the least PDI, maximum germination percentage (92.10%), root length (35.61 cm), shoot length (14.24 cm), number of pods per plant (26.97) and pod yield (3797.77 kg/ha) which proves the synergist effect of all the treatments viz., chemical, biological and organic amendment. Hence, integrated management of dry root rot combining chemical, biological and cultural practices effectively controls the disease besides enhancing the crop yields.