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.

Treating Garlic Seed Cloves with Negative Temperatures Increases the Productivity of Noble Garlic in the Brazilian Semi-Arid Region

“…These results indicate the potential of this technique, associated with sub-zero temperatures, to bring higher yields to the garlic crop in the study regions, with positive effects on the developmental characteristics and yield of the bulbs. Other authors have reported increased garlic production by treating the seed cloves below-zero temperatures [5,14].…”

“…However, the productivity of garlic cultivated in São Miguel, observed in the treatments with negative temperatures, is equivalent to the average yield of garlic produced in the southern region, with productivity ranging from 4.5 to 9.8 kg ha −1 [2]. Luz et al [14] also obtained high productivity values with the Ito cultivar, applying temperatures below zero in the pre-planting treatment of seed cloves.…”

“…This result highlights the potential of the treatments with sub-zero temperatures to increase garlic productivity. According to Luz et al [14], as the temperature of the treatments of the garlic seed cloves increases (−3 to −1 • C to 1 to 3 • C), storage for 50 days, the productivity of bulbs in the discard class is increased, which demonstrates the great advantage of using negative temperatures.…”

“…Several studies report the effect of garlic seed clove treatment using temperatures between 0 and 5 • C on garlic plants' growth, development, and productivity [4,[11][12][13]. Treatment with negative temperatures also favors garlic development, providing greater plant height, bulb ratio, and number of leaves [5], with significant increases in the production and quality of bulbs [14]. Given this, the treatment of garlic seed cloves with temperatures below zero potentially increases the production of noble garlic, favoring the development of the culture.…”