Effects of irrigation and gibberellic acid on yield and fruit quality of sweet cherry produced in high tunnels
Tunnel production of sweet cherry results in higher yields of larger fruit than in the open. When cherry trees were grown under tunnels in Norway, fruit cracking was higher in a year when soils were saturated and when 20 ppm gibberellic acid was applied at straw color. In this study we evaluated the effect of soil moisture on fruit cracking under tunnels. In 2013, a trial on mature 'Sweetheart'/'Colt' trees growing under high tunnels was initiated. Each plot consisted of 8 trees, spaced 2×4 m apart with 'Lapins' as guard trees. Experimental design was a split-plot design with or without 20 ppm GA3 application at straw color; and three drip irrigation regimes (zero, deficit and full based on evapotranspiration). During the season, soil water content was monitored weekly. Due to unfavorable weather conditions during bloom time, crop loads were lower than normal. Average fruit sizes were large and GA3 application at yellow straw color resulted in small increases in average fruit diameter and fruit weight with all three irrigation treatments. Fruit cracking was very variable and occurred almost exclusively at the distal side of fruit and not on the stem side. GA3-treated fruit cracked slightly more than untreated fruit. There were no differences in fruit cracking due to irrigation scheme.
Meland, M., Maas, F. and Kaiser, C. (2017). Effects of irrigation and gibberellic acid on yield and fruit quality of sweet cherry produced in high tunnels. Acta Hortic. 1177, 307-312
'Sweetheart' Prunus avium L., protected environment, fruit cracking, fruit firmness, fruit quality