Solução conservante floral como alternativa à solução havaiana na hibridação da cana-de-açúcar (Saccharum spp.)

Abstract

The hybridization process of sugar cane is characterized as the primary phase for genetic improvement. During this process, it is essential the use of preservative solution since it is responsible for maintaining the stalks metabolism. Currently, breeding culture programs (nao sei), including PMGCA / CECA / UFAL uses preservative solution known as Hawaiian, which has in its composition sulfur dioxide (SO2), element considered toxic to the environment and to humans. With the emphasis now given to sustainable development and to health care and the welfare of workers, combined with the requirements established by public agencies to reduce the environmental impacts caused by toxic elements, there is the need to seek new alternatives in the conservation of stalks during the hybridisation process. The objective of this study was to evaluate a trademark of a preservative solution as na alternative to Hawaiian Floral Solution in the process of hybridization of sugarcane in the conditions of Flowering and Crossing Serra do Ouro Station. The experiment was conducted in a completely randomized design in hierarchical classification scheme. The first factor rated was cross containing two levels of parents (1 parent pollen receptor; 2- parent pollen provider) and the second factor preservative solutions within the crossing for the maintenance of stalks containing four levels (1 Hawaiian Solution ; 2- Preservative Floral plus 0.3 mL.L-1 non-volatile acids (CF1); 3- Preservative Floral plus 0.4 mL.L-1 non-volatile acids (CF2); 4- preservative floral plus 0.5 mL.L-1 nonvolatile acids (CF3). The variables studied were the percentage of fertile spikelets, the physiological potential of the spikelet in two conditions (laboratory and greenhouse), and the number of viable seedlings, plant height, leaf area and dry mass of seedlings grown for 60 days. The data were submitted to analysis of variance. To the crossing factor we used the Student t test for comparison of contrasts and for the preservative solution factor in the intersection, it was applied the F test for orthogonal contrasts mean comparison. The results from sugarcane hybridization, show that the Hawaiian solution gave better results than the Floral preservative solution in all variables regardless of the concentration of non-volatile acids added. Based on the results obtained, the use of Floral Preservative Solution in both evaluated tests (laboratory and greenhouse) reduces the physiological potential of spikelets in relation to Hawaiian solution. Considering the damage to the environment caused by the Hawaiian solution and market requirements, its replacement by Floral Preservative Solution should be considered. New research should be carried out, testing new concentrations of nonvolatile acids and possible changes of the solution during the hybridization process.