Vernalization temperature and maturation point of seed cloves on garlic production and quality

ABSTRACT Brazilian producers have been seeking to improve garlic productivity and quality via vernalization at negative temperatures. However, more concrete information about the application and effects of this technique on the productivity and quality of noble garlic varieties is lacking. Moreover, there are also questions about the use and influence of seed cloves at different maturation points on this crop’s yield. Therefore, the objective of this work was to evaluate the effects of vernalization temperatures and different maturation points of seed cloves on the yield and quality of noble garlic cultivars. Three experiments were conducted using the Ito cultivar over three garlic planting seasons in Cristalina, GO, Brazil. The experimental design followed a 3 x 3 factorial scheme: three vernalization temperature ranges (-1 to -3 °C; 1 to 3 °C; and 2 to 4 °C) and three seed clove maturation points (normal, early and late). Plant height, aboveground fresh mass, bulbar ratio, and bulb yield and quality were evaluated after harvesting. The negative vernalization temperature had significant results with the highest garlic yields occurring in all three planting seasons, with a considerable increase in the quantity of bulbs with better commercial value (‘class 6’) and a decrease in the quantity of ‘discard’ bulbs. In comparison to the other temperatures, negative vernalization temperatures also yielded higher fresh plants in all evaluated seasons. The normal maturation point resulted in gains in total bulb yield. The use of below-zero vernalization temperatures increased the productivity of the garlic cultivar Ito under the conditions found in Brazil.