Avaliação do efeito do tratamento da semente do arroz - oriva sativa l. - na germinação e no controle de bypolar orizae

Abstract

The present work consisted of evaluating the effect of 4 treatments on rice seeds (Orvza sativa L. ), on their germination and on the control of Bipolaris oryzae. Rice seeds and fungicides were provided by SEMOC (Sementes de Moçambique). In this work, the wet chamber method was used in the pathological test and the sand method in the germination test. The four treatments in question included the fungicides Vitavax (100 microliters of vitavax + 100 microliters of water per 33g of seed) and Mancozebe (0.056g of mancozeb per 40g of seed), dry heat (70°C for 10 consecutive days) and the moist heat (56°C for 10 minutes). The samples were subjected to these treatments using a completely randomized design and 4 replications for each treatment. The fungus under study was cultivated and inoculated in the seeds due to the low percentage of infection by the fungus in them. The treatments mentioned above were performed in order to see which of these is the most effective in controlling B. oryzae without harming seed germination. The results were as follows: Germination test: seeds treated with vitavax, mancozeb and moist heat had significantly higher germination percentages compared to those treated with dry heat, which did not germinate and those without any treatment (control). Thus, we can infer that the three treatments had the same effect on the germination capacity of the seeds. Pathological test: seeds treated with mancozeb and with dry heat showed total control of Bipolaris oryzae , untreated seeds showed a high percentage of infection and those treated with vitavax and with moist heat showed very low percentages of infection. In summary, all treatments have the same level of efficiency in controlling the fungus, and treated seeds have higher germination values ​​compared to untreated seeds.