Crescimento, fisiologia e produção do meloeiro "pele de sapo" cultivado sob diferentes lâminas de irrigação

Abstract

The Brazilian Northeast for having satisfactory edaphoclimatic conditions for growing melons stands out as the largest national producer, and the use of irrigation together with proper plant nutrition is an important factor for quantitative and qualitative increase of the production. In this region, the hidric resource is limited and the distribution of rainfall doesn‟t furnish satisfactorily the water requirements of crops throughout the year with needing of water supply for the growth and development of plants. In this sense, the objective of this work was to evaluate either growth parameters, as well as physiological and biochemical parameters of plant and physicochemical parameters of Pele de Sapo melon fruit under levels of water replacement. The research was conducted in the experimental area in the Campus IV, Universidade Estadual da Paraíba. The research involved the study of four levels of replacement of plant water requirements (40, 60, 80 and 100 % of ETo) in Pele de Sapo melon in randomized blocks design with five replications. The following variables were evaluated: growth (leaf area and dry matter partitioning), physiological (gas exchange and chlorophyll fluorescence), biochemical (organic solutes and antioxidant enzymes), and physicochemical (mass, longitudinal and transverse diameter, flesh thickness, vitamin C, acidity, pH and °Brix of the fruit). Proline has an indicating action of overcoming the stress. The rehydration of plants increased the content of photosynthetic pigments. Higher rates of water replacement increased the mass, diameter and pulp of Pele de Sapo melon. The water replacement rate of 100 % of ETo led significant change in the Internal Carbon (IC) and Transpiration (E).