Deslintamento, neutralização e tratamento químico sobre a qualidades de sementes de algodão armazenadas

Abstract

Cotton farming is one of the agricultural activities with a great impact on the world economy, in Brazil, it has been gaining prominence in the national agribusiness due to its great contribution and socioeconomic importance. Currently, Brazil occupies the fifth position among the world's major producers, a position of privilege conquered through advances in the development of research aimed at increasing productivity and increasing investment in the adoption of technologies for crop management. During the cotton processing process, it goes through the ginning stage, which aims to separate the fiber from the seed, after this stage the seeds are still coated with short fibers called linter. In order to eliminate the linter, we move on to another step, which is delinting, which can be carried out in several ways. In addition to delinting, seed treatment with phytosanitary products is a widely adopted and impactful technique. In this sense, it was proposed in this research to study the levels of delinting, types of neutralizing and chemical treatment on the physiological and sanitary quality of cotton seeds before and after storage. For this, the work was divided into four chapters. Having aimed in the first chapter, to determine the effect of delinting and neutralizing residue on the physiological quality of stored cotton seeds through image analysis. In the second, the objective was to analyze the effects of combinations of delinting levels and compositions of chemical treatments on the physiological and functional qualities of stored cotton seeds. The third chapter aimed to evaluate the influence of delinting levels on the sanitary and physiological quality of treated and stored cotton seeds. And in the fourth chapter, the effect of the implications of the doses and volumes of syrup in the chemical treatment on the physiological quality of cotton seeds was evaluated. It can be inferred that the neutralizing Quicklime, Hydrated Lime and Lime filler did not harm the physiological quality of cotton seeds, however, the neutralizing NaOH has a continuous effect after storage, reducing the physiological quality of cotton seeds. Digital image analysis was efficient in identifying differences in vigor levels. Seeds with the correct delinting close to 100%, or at least 90%, showed higher physiological and physical/functional qualities, both at the beginning and after storage. The spray mixture with the combination of Dynasty® fungicide, Cruiser® 350 FS, Fortenza® 600 FS® and Avicta® 500 FS nematicide was efficient in controlling Aspergillus sp. and Fusarium and eradicated the occurrence of Colletotrichum gossypii and Penicillium sp., which consequently contributed to the maintenance of sanitary and physiological quality in storage. Syrup volumes of 3100, 3600 and 4100 mL.100 kg-1 did not affect seed germination when not stored, but reduced vigor.