Ecophysiological and biochemical behavior in young plants of Parkia gigantocarpa Ducke subjected to waterlogging conditions

Abstract

The Parkia gigantocarpa is a neotropical tree that naturally occurs in terra firme forest and floodplain. The aim of the study was to evaluate the physiological and biochemical behavior in young plants of P. gigantocarpa subjected to waterlogging conditions. The waterlogging was imposed at approximately 5 cm above the blade surface of the soil using pots with a capacity of 14 kg of substrate. The experimental design was completely randomized with two water conditions (control and waterlogging) combined with five evaluation times (0, 4, 8, 12 and 16-days waterlogging conditions). The variables evaluated were: Predawn water potential ( p Ψ); the foliar xylem water potential ( x Ψ); hydraulic conductivity; concentration of nitrate; nitrate-reductase activity (NRA); glutamine-synthetase (GS); total soluble amino acids; proline; glycine-betaine; alcohol-dehydrogenase (ADH) and lactatedehydrogenase activity (LDH). The significant reduction in x Ψ and hydraulic conductivity continued until the 8th day in plants subjected to waterlogging, with subsequent stabilization. The concentration of nitrate, NRA, GS, and total soluble amino acids reduced significantly, in the leaves of plants subjected to waterlogging. The waterlogging increased the proline and glycine-betaine, mainly, in the leaves. The ADH activity was significantly higher in the root of the flooded plants, especially, on the 16th day of flooding. In the same period, the LDH activity showed the highest values, mainly, in the leaves of flooded plants. The results showed susceptibility of young plants of P. gigantocarpa subject to waterlogging conditions.

Desenvolvimento e qualidade de mudas de Parkia gigantocarpa Ducke (Fabaceae) em função de fertilizante de liberação controlada

“…Esses fertilizantes, aliados a um substrato de alta qualidade, podem contribuir para reduzir o tempo de formação das mudas, as perdas dos nutrientes por lixiviação e volatização, proporcionando diversas vantagens para o ciclo produtivo em comparação com os fertilizantes comumente utilizados [13,14]. Diversos autores comprovaram os benefícios promovidos pelos FLC, principalmente nos parâmetros fisiológicos e morfológicos das plantas, como incrementos na área foliar, aumento do diâmetro do coleto, na transpiração, fotossíntese, alocação da biomassa, conteúdo nutricional e na qualidade de mudas [15][16][17].…”