This study aims to evaluate the efficacy of hot water and chitosan treatments to control green mould caused by Penicillium digitatum in 'Murcott' tangor. P. digitatum conidial germination and mycelial growth were evaluated in assays in vitro to verify whether chitosan (0.5, 1 and 2%) or hot water (45, 50, and 55°C, for 30 s, 1, 2, and 5 min) acts directly on fungus development. In vivo assays consisted of inoculating the fruit with P. digitatum (105 conidia ml−1) 4 hr before the chitosan and hot water treatments. Subsequently, green mould incidence and severity were evaluated in fruits stored at 25°C/80% RH for 4 days. Also, treatments combining chitosan and hot water were investigated for controlling green mould and the effect on postharvest quality of fruit stored at 5°C/90% RH. The results showed that P. digitatum conidia germination and mycelial growth were significantly reduced by the hot water treatments especially at 50°C/5 min and 55°C/2 or 5 min in the first case and 50 and 55°C/5 min in the second. These two treatments, when applied alone, 1 min dipping in 2% chitosan or hot water at 50°C/5 min, significantly reduced green mould development in fruit kept at 25°C/80% RH or refrigerated. However, the hot water dip combined with chitosan did not improve green mould control on ‘Murcott’ tangor at room temperature or under refrigeration. Besides, chitosan and hot water did not impair fruit quality. Thus, chitosan and hot water could be an alternative to synthetic fungicides to control green mould in citrus while also contributing to a decrease in the postharvest losses of ‘Murcott’ tangor.

Because it is a highly perishable fruit, due to its high metabolic activity and water content, the strawberry has a shelf life limited by weight loss, texture alteration and microbiological deterioration. Such susceptibility to proliferation of microorganisms and the occurrence of postharvest diseases, especially some rot, stimulates the study of alternative sanitizing treatments that aims at the maintenance of fruit quality such as ultraviolet radiation, which it exhibits germicidal properties in the region UV-C (200-280nm). The non-formation of residual toxic compounds on the surface of the product, a low cost and the fact of being odorless are advantages of its use in fruits and vegetables.¹ In the present study the objective was to evaluate the efficacy and effects of UV-C radiation in strawberries by applying 0.0 (T1), 1.25 (T2), 2.50 (T3), 3.75 (T4) and 5.0 (T5) kJ/m² and storage at 5.37 ± 0.74 ºC and 53.38 ± 6.84% RH after irradiation. The experiment was conducted in a completely randomized blocks design with three replicates per treatment. In the results, it was not possible to observe some benefits of UV-C in strawberries in relation to their non-use, suggesting it needs further studies with different doses and storage conditions.