Isoenzyme activity in maize hybrid seeds harvested with different moisture contents and treated

Atividade isoenzimática em sementes de milho híbridos colhidas com diferentes teores de água e tratadas

Abstract:

The analysis of isoenzyme activity is an important monitoring and characterization tool of the physiological quality of seeds and to understand the deterioration. The purpose of this work was to study the isoenzyme expression allied to the quality of maize hybrid seeds harvested at different moisture levels and subjected to chemical treatment. A completely randomized experimental design was used with four replicates, in a 3x2 factorial arrangement with three moisture levels (45%, 40% and 35%), and two forms of seeds tillage (with and without treatment). Seeds from maize hybrids, semi-hard BM 810 and dented BM 3061, were used. Seeds were manually gathered on ears. Chemical treatment was performed with commercial products Maxin^(r) + K-obiol^(r) + Actellic^(r). Seed quality was assessed by moisture test, incidence of mechanicals damage, first count of germination, germination, emergence, emergence speed index, mean emergence time, accelerated aging, and electrical conductivity. Isoenzyme expressions were assessed by means of the systems superoxide dismutase (SOD), catalase (CAT), esterase (EST), alcohol dehydrogenase (ADH), malate dehydrogenase (MDH), peroxidase (PO) and α-amilase. Isoenzyme expressions are different, depending on moisture levels at harvest, the hybrid maize and seeds quality. Seeds treatment does not interfere in their isoenzymes expression.

Index terms:
Zea mays ; isoenzyme expression; physiological quality