Tratamento de sementes de milho com peróxido de hidrogênio: análise fisiológica e sanitária.

Abstract

The sanitary quality of maize (Zea mays L.) seeds is a requirement that is of great importance for agricultural production, since the phytopathogenic microorganisms associated with them can cause anomalies and lesions in plants, as well as seed deterioration and low productivity. However, the greatest damage is caused by the action of fungi during the germination process. Thus, the objective of this research was to analyze corn seeds in the physiological and sanitary scope, submitted to different doses of hydrogen peroxide. Corn seeds were collected in the municipalities of Camalaú-PB. For the sanity test, the seeds received the following treatments: T1: control (untreated seeds); T2: dicarboximide fungicide (240 g a.i./100 kg of seeds); T3, T4, T5, T6, T7, T8, T9, T10: immersion of seeds in 0.5% aqueous solution; 1.0; 1.5; 2.0; 4.0; 6.0; 8.0 and 10.0% hydrogen peroxide (H2O2) for five minutes, respectively. The total amount of solution used (distilled water + hydrogen peroxide) was 100 mL for each treatment solution. In the germination test, the same treatments described in the sanity test were used. The design used in the experiments of sanitary and physiological analysis was completely randomized (DIC). Regression analysis was performed for quantitative data with the significance of the models verified by the F test (p ≤ 0.05). The following fungi were identified in the corn seeds: Aspergillus flavus (34%), Aspergillus niger (14%), Penicillium sp. (20%), Cladosporium sp. (10%), Fusarium sp. (37%) and Colletotrichum sp. (4%). The concentrations of 4, 6, 8 and 10% of hydrogen peroxide were efficient in the reduction of fungi: Aspergillus flavus, Aspergillus niger, Penicillium sp., Cladosporium sp., Fusarium sp. and Colletotrichum sp. There was a 3% reduction in germination when the seeds were submitted to concentrations of 6, 8 and 10% of hydrogen peroxide. The vigor of corn seeds submitted to the treatments was 80.3%, considered as average vigor. The concentration of 4% hydrogen peroxide was efficient in the sanitary and physiological quality of corn seeds.