THE INFLUENCE OF THE CLIMATIC FACTORS ON THE DEVELOPMENT AND YIELD CAPACITY OF SOME APPLE VARIETIES CULTIVATED IN HIGH DENSITY ORCHARD SYSTEM

Researches have been effectuated in a high density apple orchard (2500 trees/ha) established in the year 2001 with apple varieties resistant or tolerant to scab (Venturia inaequalis), Florina, Generos, Auriu de Bistrita grafted on rootstocks M9 and M 26.Growth and yield capacity of trees was influenced in the period 2001 and 2011 beside the fruit growing technology also by the evolution of climatic factors. The effects of drought has influenced the fruit production quantitatively and qualitatively through an increase of medium and little sized fruits in the years 2002 (118.5 mm rainfall deficit when compared with 677 mm/ year normal atmospheric precipitation quantity), 2003 (rainfall deficit 244.2 mm) and 2011 rainfall deficit 181.5 mm). In the 11 years of studies there have been registered hail droppings, in the year 2004, phenomena which has contributed to the quality depreciation of the fruit production. Also in the year 2007 in the period of blossom there have been registered low temperatures ( -2.8˚C) which have been contributed to the reduction of the fruit production. The growth and yield capacity of the fruits in the eleven years have been influenced by the age of fruit trees, by the rootstock-scion combination, training system and not least by the evolution of the climatic factors.