EFFECT OF MULCHING WITH GRASSES AND CHEMICAL TREATMENT ON WHITE MOLD (Sclerotinia sclerotiorum) IN COMMON BEAN (Phaseolus vulgaris L.)

摘要

White mold of common bean, caused by the soilborne pathogen Sclerotinia sclerotiorum, is one of the worst yield-limiting diseases in brazilian plantations. The employment of straw mulch on soil surface on the reduction of pathogen sclerotia's germination and white mold severity were reported previously (Civardi et al. 2019). However, most cover crops traditionally used for this purpose have high decomposition rates in tropical climates, not allowing sufficient soil cover and consequently protection of S. sclerotiorum hosts. The common bean crop in Brazil is the second largest in the world, exceeding 3.0 million tons on around 2,7 million ha annually. Although brazilian total production is half of India's, the south american country employs only 18%of the area used by India (FAOSTAT 2019). Hence, there is a strong demand for eco-friendly methods that provide efficient soil protection to manage white mold and improve bean production systems. Cultural practices recommended for the management of soilborne pathogens such as S. sclerotiorum must be associated with no-tillage cropping (NT), considered essential for sustainability of annual crops, once NT systems benefit the physical, chemical and biological soil components and therefore the dynamics ofplant diseases (Silva et al. 2018). Despite the limited management options of white mold in common bean, cultural control with straw mulch for the no-tillage system and conscious chemical control with specific fungicides are efficient practices that canhelp the management of the disease. The aim of this work was to verify the effects of mulching with different vegetal species, volumes of straw mulch and chemical treatment with fungicide on Sclerotinia sclerotiorum by verifying grain yield of common bean.