Caracterização e termoanálise de variedades de cana-de-açúcar no bioma Cerrado.

Abstract

The objective of this thesis was to evaluate the agronomic, chemical and bromatological characters of twelve sugarcane varieties (IAC: 86-2210; 86-2480; 87-3396; 93-6006, RB:72-454; 73-9735; 75-8540; 86-7515, and SP: 79-2233; 80-1842; 80-3280; 81-3250), in order to assist in decision-making in choosing the most suitable variety for feeding cattle. In chapter 1, a study was developed with the objective of characterizing the chemical and agronomic composition of sugarcane varieties for feeding ruminants during the year 2018 and 2019. (CC), node number on the plant (NODE N), distance between nodes (DEN), diameter (DIÂ), number of leaves, (NF), leaf length (CF), leaf width (LF), dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), non-fiber carbohydrates (NFC), in vitro dry matter digestibility (DIVMS), digestibility in vitro of organic matter (IVMOD). The experiment was set up in a randomized block design in split plots. Correlations were obtained by Person's correlation analysis and t-test. The year 2018 was the one with the highest nutritional and productive indices. The RB 8675-15 and RB 72454 varieties showed greater viability for use in animal nutrition. Chapter 2 aimed to determine the thermal behavior of twelve varieties of sugarcane using thermogravimetry and thermogravimetry derived from the stem of commercially available sugarcane. The characterization of the energy potential of the culm was performed using thermogravimetry and derived thermogravimetry (TG-DTG). The degradation of the RB 75-8540 variety showed the lowest weight loss equivalent to 92.38%, followed by the IAC 87-3396 variety, which showed a weight loss of 94.52%. Comparing the thermogravimetric curves of the twelve varieties, SP 81-3250 stood out with the highest mass loss 97.04%, it had a slower burning process. Thus, the varieties RB 86-7515 e RB 72-454, stand out in their nutritional aspects and low energy loss in the process of weight loss.