Bacillus subtilis and Trichoderma harzianum on the quality and occurrence of anthracnose in bananas

Abstract

The objective of this study was to assess the efficiency of Trichoderma harzianum and Bacillus subtilis on postharvest control of anthracnose, the effects on postharvest quality in ‘Nanicão’ bananas, and the sensory acceptance of fruits. In vitro and in vivo tests were performed. The in vitro tests included the following treatments: control (distilled water), T. harzianum, B. subtilis, and thiabendazole. In vitro tests consisted of pairing Colletotrichum musae with T. harzianum and B. subtilis by daily measuring the mycelial growth of C. musae and by counting the spore germination of C. musae. For in vivo tests, the treatments were control (distilled water), T. harzianum, B. subtilis, T. harzianum + B. subtilis, and thiabendazole. In vivo tests consisted of a daily evaluation of the incidence and severity of anthracnose in ‘Nanicão’ bananas. Some physicochemical characteristics of fruits were evaluated (weight loss, color, pulp firmness, soluble solids (SS), titratable acidity (TA), pH, and SS/TA ratio), as well as the sensory acceptance of bananas. Based on the results, the application of T. harzianum in ‘Nanicão’ bananas was efficient in decreasing the severity of anthracnose caused by C. musae, but treatments with biological control agents were inefficient in this process. On postharvest quality, treatments with biological control agents seem to have accelerated the maturation process. However, results from the sensory analysis showed that fruit acceptance was not affected.