Fluctuations of Production and Quality of Bananas Under Marginal Tropical Climate

The knowledge of the inter-seasonal fluctuations in characteristics of fruit quality and production is important for management of plants, prediction of yield and marketing strategies. This study aims to evaluate how the climatic conditions prevailing in the month of harvest impact bunch mass and variability of the size and color of the banana fruit 'Nanica' and 'Prata' cultivated under marginal tropical climate. The experiments were carried in Registro, Ribeira Valley region, São Paulo, Brazil, in a completely randomized design with 24 treatments (months of bunch harvest) and ten replications, for each cultivar. Cyclic seasonal fluctuations in production were found in for the two cultivars, with the lowest bunch mass (BM), fruit size consistently recorded between July and February associated with lower global solar radiation (Rad) and temperature (T) of the harvest month, but not precipitation (Ppt). The extension of monthly fluctuations in BM were similar to 'Prata' (18.95±3.31 kg) and 'Nanica' (29.51±4.69 kg). Independent of the harvest month, there was a trend of greater variability for fruit length (FL) and lower for fruit diameter (FD) between fruits of the different positions in the bunch. The correlations between Rad or T of harvest month with BM, FL, FD and SL were all positive. For both cultivars, the shelf life (SL) was longer for fruits of the last hand. There were also positive correlations between Rad or T with SL. The decrease of peel color characteristics of the 'Nanica' fruit was associated with cold fronts from autumn to spring and chilling injury, with higher intensity in the last hand.