INFLUENCE OF CLIMATIC CONDITIONS ON YIELDS AND FRUIT PERFORMANCE OF NEW APPLE CULTIVARS FROM THE CZECH REPUBLIC

Yields, fruit size and some other fruit characteristics of apple trees on ‘M9’ rootstock were monitored in 35 orchards located in different climatic conditions of the Czech Republic between 1996–2001. Altogether 31 cultivars, mostly newly bred in the country and some standard ones, were ranged according to their average yield per tree, specific productivity (based on a unit of canopy volume), and mean fruit weight in three groups of orchards with different climatic conditions.
These three groups were based on average annual mean temperature like: cold (below 7.5°C), medium (7.5–9°C) and warm (above 9°C), which roughly corresponded to decreasing altitude: over 400 m, 200–400 m, and less than 200 m above sea level respectively.
Majority of studied cultivars differed considerably in yields, cropping efficiency, fruit size and some other fruit characteristics in a relation to different climatic conditions.
The most productive cultivar that also gave the highest average yield per tree was ‘Produkta’. However in the cold climatic conditions the best cropper was ‘Jonalord’. ‘Rajka’, ‘Selena’ and ‘Otava’ were also generally very productive.
On the contrary the lowest yields were observed in case of ‘Rubin’, ‘Bohemia’, ‘Rubinola’ and ‘Julia’. ‘Angold’, ‘Rubin’, ‘Bohemia’, ‘Melrose’, ‘Jonalord’, ‘Zuzana’ and ‘Vanda’ belonged among cultivars with very big or big fruits.
Above-average size of fruits was further typical for ‘Jarka’, ‘Gloster’, ‘Delor’, ‘Goldstar’, ‘Glockenapfel’ and ‘Produkta’. On the other hand round ‘Julia’ and ‘Karmina’ had on the average the smallest fruits.
Beside them small fruits sometimes appeared also in ‘Otava’, ‘Florina’, ‘Resista’ and ‘Elstar’.