Inativação fotodinâmica das sementes, técnicas de conservação e anatomia dos frutos de mangaba em desenvolvimento

Abstract

Mangaba is a fruit with potential for exploration. However, some information about its biology is unknown, and there are also obstacles to its consolidation in the market and the propagation of the species. This study is divided into chapters with different objectives. The first and second chapters present a general introduction and a literature review of the main topics covered in the experimental chapters, ranging from the general characteristics of the species to post-harvest conservation techniques, seed health quality, and fruit anatomy. Chapter three aims to anatomically characterize the pericarp of the fruit of Hancornia speciosa Gomes var. gardneri, found in the Brazilian Cerrado, during its development to maturity. The results detail important structures related to the survival and perpetuation of the species, as well as aspects of the fruit's post-harvest quality. In this sense, new information is described in the anatomical characterization of the fruit, making this study fundamental for understanding the biology of the species. Chapter four aims to determine whether photodynamic inactivation and immersion in sodium hypochlorite are effective in reducing pathogens in seeds. This study involves three experimental parts: seeds immersed or not in 1% sodium hypochlorite to evaluate the occurrence of endophytic fungi; in vitro inactivation with methylene blue and toluidine blue irradiated with LED light to assess the mortality of the pathogens found in the previous experiment; and the physiological quality of seeds treated with the saniti zers used in the other two experiments regarding germination, germination speed index, first germination count, primary root protrusion, seedling length, and seedling fresh and dry weight. The results show that 1% sodium hypochlorite and inactivation with methylene blue and toluidine blue are effective in fungal control in mangaba seeds, eliminating up to 100% of the fungi without compromising physiological quality. The fifth chapter aims to evaluate the effects of hydrocooling on the preservation of mangaba fruits stored at ambient and refrigerated conditions. The parameters evaluated include mass loss, soluble solids, titratable acidity, soluble solids/titratable acidity ratio, pH, firmness, vitamin C content, luminosity, chromaticity, and hue angle. The results show that storage temperature and the time spent immersing the fruit in ice water influence the effect of hydrocooling, and it is not possible to extend the shelf life of mangabas. Mangabas can be stored at 5°C and 10°C for 12 days. Conversely, deterioration occurs after eight days at 25°C. The final chapter aims to evaluate the effects of the combination of hydrocooling and calcium chloride on mangaba storage. Mangabas were evaluated based on mass loss, soluble solids, titratable acidity, vitamin C, firmness, soluble pectin, and polygalacturonase. Storage temperature and low relative humidity influenced the effect of hydrocooling combined with calcium chloride, which was not effective in extending the shelf life of mangabas.