Tecnologia de sementes de Pachira aquatica Aubl

Abstract

The experiments were carried out at the Laboratory of Seed Analysis - (LSA) of the Universidade Federal Rural de Pernambuco/Unidade Acadêmica de Garanhuns UFRPE/UAG in Garanhuns-Pernambuco. The fruits and the stakes of Pachira aquatica Aubl. were collected from five mother trees located on the campus of UFRPE/UAG, aiming to evaluate the physiological quality of seeds of P. aquatica subjected to drying, and salt stress, and the influence of plant extracts the rooting of P. aquatica to contribute to scientific and technical knowledge to deploy this new oilseed areas in the state of Pernambuco. The first experiment was conducted with seed drying at temperature of 35 ºC, the following exposure periods of 0 (without drying), 24, 48, 72 and 96 hours; and evaluated the water content, germination, first count and rate of germination rate, length and dry weight of roots and shoots of seedlings. Data were subjected to analysis of variance and regression. The second experiment simulation of salt stress was performed using as solute sodium chloride (NaCl) at concentrations of 0,0 (control); 3,0; 6,0; 9,0; 12,0 and 15,0 dS.m-1 diluted in distilled and deionized water, then the seeds were germinated at temperatures of 25 ºC and 30 ºC. The experimental design was completely randomized, and evaluated the germination percentage, speed of germination, seedling length (root and shoot) and dry mass of shoots. In the third experiment the rooting of P. aquatica immersed in water, immersion in commercial fertilizer Forth®, immersion extract of Salix babylonica (10, 25, 50 and 100%) and immersion in extract of Cyperus rotundus was performed (10, 25, 50 and 100%). Treatments were arranged in completely randomized design, and 60 days after planting the cuttings were conducted evaluations of rooting percentage, number of roots/cuttings, number of shoots, number of leaves, number of cuttings with shoots and dry weight leaves. The seeds of Pachira aquatica species are scattered with very high water content (55%), and a small reduction in value commits physiological quality, allowing the characterization of the seeds of this species as recalcitrant. Increasing the salt concentration in the substrate reduces the germination and seed vigor P. aquatica, especially when the seeds are subjected to a temperature of 25 ºC. P. aquatica seeds are tolerant to salinity, temperature under 30 ºC, with a reduction in seed germination at concentrations above the concentration of 6.0 dS.m-1. The P. aquatica is an easy to root species, the use of commercial fertilizer and phytohormone Forth® not necessary. The application of leaf extracts of Cyperus rotundus and Salix babylonica not a viable alternative in the production of seedlings of P. aquatica.