Alternative control of post-harvest diseases in Tainung 1 papaya

Abstract

Controlling post-harvest papaya diseases without using agrochemicals is a challenge for producers. This study aimed at evaluating the effect of clove essential oil, biological fungicide (Trichodermil^®), resistance inducer (Cob Sistem^®) and chemical fungicide (Imazacure^®) on the in vitro control of phytopathogenic fungi isolates from papaya as well as on the post-harvest quality of Tainung 1 papaya. The in vitro experiment was conducted in a complete randomized design, with five fungal species x five treatments and five replications. The in vivo experiment was conducted in a complete randomized design, with five treatments x five storage times, five replications and three fruits per replication. The fruits were stored under refrigeration at 10 ± 2 ºC and 90 ± 5 % of relative humidity and evaluated at 0, 7, 14, 21 and 28 days of storage, plus two shelf life days at 25 ± 2 ºC, to simulate marketing conditions. The inhibition of mycelial growth was evaluated in the in vitro experiment, while the diseases occurrence and post-harvest quality of the fruits were evaluated in the in vivo experiment. The clove essential oil and Trichodermil^® were as efficient as Imazacure^® in inhibiting the mycelial growth of Alternaria sp., Colletotrichum gloeosporioides and Rhizopus sp. The treatments with clove essential oil, Trichodermil^® and Imazacure^® were similar in controlling the pathogens up to 21 days of storage. The treatments had no effect on the fruits soluble solid contents.