Ácido ascórbico exógeno no vigor de sementes de limoeiro ꞌCravoꞌ

Abstract

Studies about seed germination of citrus rootstock species are important, since that the low longevity and slow germination compromises the seedling production. The ascorbic acid (AA) increases the synthesis capacity of DNA by cells stimulation and proliferation, with possible effects on seed germination. This work aimed to evaluated the effect of solutions of AA (Control; 0,05 mM; 0,1 mM; 0,5 mM e 1 mM of AA) on the vigor of seeds rangpur lime (Citrus limonia Osbeck cv Cravo) seeds, with or without tegument, at 12 and 24 hours of immersion. Two additional control treatments also were tested: water and water + phosphate buffer 0,01M (1:1). After this time, the sowing of seeds was done in trays containing vermiculite as substrate. It was evaluated the speed index emergency and emergency rate of seedlings. It was observed that the AA solutions and the immersion for 24 hours are detrimental to vigor of seed without tegument, and the phosphate buffer 0,01M pH 5,9 had favorable effect on the seed vigor of rangpur lime seed with or without tegument.