Qualidade fisiológica de sementes de variedades de milho sob estresse por alagamento e respostas no armazenamento em diferentes embalagens

Abstract

Maize is one of the most important crops in the world, part of human food, as well as animal feed. In view of its importance, it is necessary to research possibilities of different varieties in order to overcome production barriers. Flooding for long periods is harmful to seeds of some varieties of corn, and the seed deteriorates until it loses its qualities. Another important factor to be taken into account is the type of packaging with the greatest capacity to maintain the viability and vigor of the seeds, aiming at the reality of family farming and small producers. The tests were conducted at the Seed Analysis Laboratory of the Federal University of Pelotas. For the first chapter, the seeds were subjected to flooding treatments for periods of 0,1,2,3,4 and 5 days at 27 ° C. After the periods, evaluations of the first germination count, germination, cold test without soil, length and weight of dry mass were carried out. For the second chapter the seeds were stored in paper bags and PET bottles for a period of six months under ambient conditions. After this period, evaluations of the first germination count, germination, cold, length, dry mass, tetrazolium, electrical conductivity and emergency were carried out. Thus, the objectives of the present work were: 1) To evaluate the physiological quality of seeds of different varieties of maize, which were induced to flooding in periods of time; 2) To evaluate the physiological quality of seeds of varieties of Creole and hybrid maize, stored, in a period of six months, in permeable (paper bags) and impermeable (PET bottles) packages. The main conclusions obtained were: 1) The flooding of corn seeds for different periods of time, affects their physiological quality, decreasing percentages of germination, vigor, length and dry mass, however, the varieties: All 25, was the most stable and vigorous in the tested flooding periods .; 2) The Pampa variety has greater seed storage potential and lots stored in PET bottles showed less deterioration over the six months of storage, showing good quality at the end of the period, pointing out that they can be a good alternative for storage of small lots of seeds.