Effect of Organic Amendments on Pigeonpea stem canker incited by Macrophomina phaseolina (Tassi) Goid under Pot Culture

Abstract:

Stem canker of pigeonpea, incited by Macrophomina phaseolina (Tassi) Goid, is recognized as one of the most widespread and damaging diseases, especially under rainfed farming conditions. Its soil-borne nature and complex disease cycle make effective management in the field quite challenging. In view of this, a study was carried out during 2023–24 to examine the potential of different organic amendments in managing this disease in pigeonpea (Cajanus cajan). Nine organic amendments were applied to the soil before sowing and evaluated using the sick soil technique. A susceptible pigeonpea variety, Khadka, was grown in earthen pots under controlled screen house conditions. The findings indicated that all the organic treatments were effective in lowering pre-emergence and post-emergence seedling mortality, as well as total plant mortality, when compared to the untreated control. The most effective organic amendment found was Neem seed cake, with significantly highest reduction in pre-emergence seed rot PRESR (80.52%) and post-emergence seedling mortality POESM (82.08%). This was followed by Castor seed cake (66.23% and 70.58%), Linseed seed cake (53.00% and 61.00%), Safflower seed cake (50.97% and 60.16%), Cotton seed cake (47.47% and 57.72%), Poultry manure (34.34% and 46.58%), Goat manure (30.40% and 43.91%), whereas, Sunflower seed cake (25.73% and 38.92%) and Vermicompost (24.38% and 38.28%) was found least effective with significantly least reduction.