Evaluation of Estonian apple cultivars and hybrids in Latvia
Estonian apples have always been popular in Latvia. At present, ‘Tiina’ is widely grown commercially as well as in home gardens, and ‘Liivika’ is promising for organic and home orchards. A number of new Estonian apple cultivars and hybrids have been screened in 1990–2020. Several new selections by breeder Kalju Kask (Polli) are included in field trials at Institute of Horticulture - ‘Aule’, ‘Kastar’ and KK 201-2 (‘Karlote’) since 2011, ‘Kersti’ since 2014, KK 5-16 (‘Kelin’) with scab resistance gene Rvi6 and KK 2812 since 2015. Their trees were planted on dwarfing rootstock B.9 as one-year-old whips at distances 1.5×4 m, in 3 to 5 replications with 2 or 1 trees. Commercial cultivars ‘Auksis’, ‘Antei’ and ‘Zarya Alatau’ were used as controls. The highest productivity had ‘Aule’ and ‘Kastar’, the best fruit quality - ‘Aule’ and ‘Kelin’. ‘Aule’ has been highly esteemed also by some Latvian farmers. Fruits of ‘Kelin’ had the best storage, which is crucial for a cultivar’s commercial success in Latvia. On the other side, ‘Kersti’ proved to be unsuitable for Latvian conditions, having very strong tree vigour and low yields. ‘Kastar’ showed a high tendency to fruit cracking at calyx, while KK 201-2 and KK 2812 had irregular or low yields. Of newer acquisitions, scab resistant (gene Rvi6) ‘Virve’ and KK 4-11 show good preliminary results and have been propagated for trials on dwarfing rootstocks. Productivity, tree characteristics, fruit quality traits and taste panel evaluation of Estonian apples in Latvia are discussed.