Produção de porta-enxertos cítricos em hidroponia

Abstract

The appropriate propagation of nucellar seedlings of citrus rootstocks varieties is one of the most important steps in the production of budded citrus trees. The present experiment aimed to investigate the development of citrus rootstocks transferred at different heights to the hydroponic system till the grafting point. The experiment was established and conducted in a completely randomized block design following a factorial scheme: 4 rootstocks (‘Rangpur Santa Cruz’ lime, ‘Cleopatra’ and ‘Sunki Tropical’ mandarins, and the hybrid TSKC x (LCR x TR) - 059) x 3 plant heights at the transfer stage (0, 3 and 6 cm), with four replications and ten plants per plot, amounting to 480 plants. Treatment 0 (zero) corresponded to the seeds submitted to germination already in the nutrient solution whereas the treatments concerning both 3 and 6 centimeters of plant height at the transfer stage were kept up to that height in an aqueous solution then being transferred into the nutrient solution. Seed germination was evaluated through the Emergence Velocity Index (EVI) and percentage of emergence, the development of the plants as well as their biomass yield. Hybrid TSKC x (LCR x TR) - 059 had its EVI decreased when it was cultivated since germination in the nutrient solution. The mandarin varieties can be sown already in the nutrient solution. ‘Rangpur Santa Cruz’ lime and the hybrid TSKC x (LCR x TR) - 059 when transferred 6 cm high into the nutrient solution had better development both in diameter and height. These yielded a greater amount of biomass. ‘Rangpur Santa Cruz’ lime presented a leaf area larger than the other rootstocks.