Liming and biofungicide for the control of clubroot in cauliflower1

Abstract

RESUMOand summer in higher altitudes (May et al. 2007, Filgueira 2008.

Use of limestone and agricultural gypsum in cauliflower crop management and clubroot control in mountain farming

“…Root development (volume and fresh weight) and clubroot severity were also quantified. The clubroot severity was estimated with the aid of a scale composed of seven scores (0%, 8%, 20%, 42%, 68%, 87%, and 95% of roots with galls) (Santos et al, 2017). The volumes of the healthy roots (HRV) and diseased roots (DRV) were calculated based on the water displacement method, and the total volume (TRV) was calculated by the sum of the HRV and the DRV (Bhering et al, 2017).…”

“…The plants, shoot, and roots were harvested at 100 and 106 DAT, and the evaluations were performed according to the methodology described for the previous experiment. The evaluations determined disease severity (Santos et al, 2017) and root development by measuring the volume and weight of the healthy and diseased roots [HRV, DRV, TRV, HRFW, DRFW, TRFW, PDRV, PDRFW, and total root dry weight (TRDW)] and IFW and ID. Yield (Mg ha -1 ) was estimated based on the IFW.…”

“…Considering the existing limitations for the chemical and genetic control of the disease (Donald & Porter, 2009;Gossen et al, 2015), management practices are the most important strategy for reducing the losses caused by the disease. Among these, soil acidity correction is the most important, followed by basic strategies for successful crop and disease management (Dixon, 2009b;Donald & Porter, 2009;Gossen et al, 2014;Bhering et al, 2017;Santos, Amaral Sobrinho, Costa, Diniz, & Carmo, 2017). Cauliflower is a demanding crop in terms of phytotechnical, phytosanitary, and soil fertility management [pH (H₂O) = 6.0 to 6.8, V = 80%, and Ca + magnesium (Mg) content ≥ 3.0 cmol c dm -3 ] (May et al, 2007;Guerra, Leal, & Ferreira, 2013) as well as the required environmental conditions, especially temperature and humidity.…”

Clubroot disease in Latin America: distribution and management strategies

“…Trichoderma harzianum reduced clubroot incidence by 33% on broccoli in Venezuela (García et al ., ). In contrast, application of a commercial biocontrol product based on T. harzianum had no effect on clubroot incidence in cauliflower in Brazil (Santos et al ., ), or on broccoli in Colombia (Castillo & Guerrero, ) and Peru (Carpio, ). Also, application of T. harzianum together with Bacillus subtilis did not reduce clubroot severity on cabbage in Peru (Pachari, ).…”

“…The large volumes of lime required may also contribute to making the efficacy of liming inconsistent. For example, limestone applied at up to 4 t ha À1 in Brazil increased soil pH from 6.2 to basic pH values and reduced clubroot levels in cauliflower (Santos et al, 2017). In contrast, the application of 2.1 t ha À1 of dolomite limestone to a cabbage field in Colombia raised pH from 6.2 to 6.5 but did not reduce clubroot, probably because the treatment did not sufficiently change the soil pH or Ca 2+ concentration (Botero-Ram ırez et al, 2015).…”