Alternative management strategies reduced the incidence and severity of root rot of melon

Abstract

Melon (Cucumis melo L.) is one of the most economically important fruit crops in the Northeastern region of Brazil, nearly all production is exported to European countries. Because of the indiscriminate use of monoculture, the incidence of soilborne pathogens in melon fields is on the rise, resulting in increasing losses in fruit production. The objective of this study was to investigate if the incorporation of different vegetable materials (Crotalaria juncea L. and Pennisetum glaucum L.) in the soil, combined with polyethylene mulch, and the application of commercial products (Compost-Aid^® + Soil-Set^®) can efficiently control soilborne pathogens in melon fields. Two greenhouse experiments were identically set up using soil naturally infested with various phytopathogenic fungi, including Fusarium spp. and Macrophomina spp. The experimental design was completely randomized, with seven treatments and seven replications. The pathogens’ occurrence, disease incidence, and severity were evaluated, as well as fruit quality indicators (weight, firmness, and Brix Degree). Two treatments showed great potential for decreasing disease incidence, severity, and the occurrence of pathogens. One of the treatments had pearl millet (Pennisetum glaucum) incorporated into the soil that was covered with polyethylene mulch. The other treatment was when crotalaria was incorporated into the soil and covered with polyethylene mulch. Commercial products (Compost-Aid^® and Soil-Set^®) were applied in high temperatures and lower humidity, in both treatments. Plants submitted to these treatments also yielded fruits with higher weight and Brix Degree than the control treatment.