Influences of plant density and fruit thinning on watermelon hybrid production cultivated in different seasons

ABSTRACT Brazilian watermelon productivity is not efficient when compared to the largest producer countries, due to abiotic and biotic factors. Some of the difficulties are because of a small number of studies on this crop in Brazil. The aim of this study was to evaluate the effects of plant density and fruit thinning on two commercial watermelon hybrids (Talisman and Youlie), using trials which were carried out in two different seasons (April - July and August - November). The experiment was conducted in Uberlândia-MG and consisted of two managements of fruit position (A-basal and B-distal) and four plant densities (3,000, 4,000, 5,000 and 6,000 plants/ha). In season 1, the distal management was the most productive in relation to all cultivation densities. The distal management shows higher productivity in both hybrids, with greater increase in mass, productivity and 0Brix content in hybrid Talisman, however with lower density, firmness and internal cavity compared to hybrid Youlie. Weather conditions determined the influence of fruit management on watermelon crop. Cultivation during the hottest period and with a better water supply (season 2), basal management (A) showed a performance similar to the distal management. At this time, hybrid Talisman surpassed hybrid Youlie concerning productivity, average mass, fruit density, firmness and internal cavity. In both seasons, higher densities are related to higher productivities. Hybrid Talisman showed higher productivity in cultivation from April to July (season 1) under distal fruit management. RESUMO A produção brasileira de melancia é menos eficiente se comparada aos principais países produtores devido a fatores bióticos e abióticos. Parte das dificuldades vem da escassez de estudos sobre a cultura no Brasil. Em razão disso, objetivou-se avaliar os efeitos da densidade de plantas e do desbaste de frutos em dois híbridos comerciais de melancia (Talisman e Youlie), a partir de ensaios realizados em duas épocas (abril - julho e agosto - novembro). Além das duas cultivares comerciais utilizadas, o experimento, conduzido em Uberlândia-MG, consistiu de dois manejos de posição de frutos (A-basal e B-distal) e de quatro densidades de plantas (3.000, 4.000, 5.000 e 6.000 plantas/ha). Na época 1 o manejo distal é o mais produtivo em todas as densidades de cultivo. O manejo distal revela maior produtividade em ambos híbridos, com maior incremento de massa, produtividade e teor de 0Brix no híbrido Talisman, porém meno