Quality of sweet potato cultivars planted harvested at different times of two seasons
Australian Journal of Crop Science
This study aimed at adapting harvest time of different potato cultivars in two seasons during the year. Two experiments were conducted: one in the rainy season and another in the dry period. Two production factors were studied in experiments using a splitplot design in a complete randomized block design. The first factor (including 3 sweet potato cultivars: ESAM 1, Paraná and Mãe de Família) was assigned to the plots. The second factor (harvest time: 90, 105, 120, 135 and 150 days after
... ) was assigned to the subplots. Soluble solids, total soluble sugars, starch content, pulp firmness, cooking time and vitamin C were assessed. The harvest after 150 days resulted in increased levels of soluble sugars, starch, and vitamin C in both growing seasons, compared to other harvests, demonstrating that tuberization does not depend on season. In addition, late harvesting increased the cooking times with all cultivars, especially those grown in the rainy season. In the dry season, cooking time was higher for cv. ESAM 1. Of the three sweet potato cultivars, cv. Parana presented the highest total amount of soluble sugars and vitamin C, as well as faster cooking time, while cv. ESAM 1 had the highest starch content, pulp firmness and the longest cooking time. The results suggest that Paraná and Mãe de Família are feasible for the fresh market and ESAM 1 for industry, regardless of the season or harvest time. These cultivars offer growers flexibility when deciding on sweet potato crops for different purposes, i.e. fresh market or industry. Delaying the harvest of sweet potatoes until 150 days gives greater flexibility to producers in the semi-arid region of Brazil in relation to either fresh or the industrial market.