THE ESTABLISHMENT OF INTENSIVE APPLE ORCHARDS IN SERBIA
AbstractSerbia at the present time grows apple on an area of 25.917 ha with an average production of 412.000 tons per year. This production is almost 2.5 fold higher than in the period of 2001-2005., which is associated with establishment of new intensive orchards, starting from 2006.Apple production was moving from the locations, typically used for traditional apple production to the regions, mostly located in the different valleys, that poses enough quantity of fresh water for drip irrigation. The new established orchards are equipped with anti-hail net preventingfruit damagesagainst hail or intensive sunlight. The most dominant cultivars are different clones of Golden Delicious, Granny Smith, Gala and Red Delicious, which are mostly grafted on M9 rootstock. Spacing between the rows is the same as in the past (3.0-3.5 m), whileÂ distance withinthe rows is significantly reduced and now is 0,5-0,9 m, which provide 3,200-6,250 trees ha-1. Tree height reaches 2.20-3.0 m. Large and well feathered nursery trees are used for planting, which provide fast returns of high investment. "Knip" nursery treesÂ as 2-year-old trees with one-year old crown are preferred for establishing new orchards. After planting, light pruning is usually applied. Only lateral shoots at the tip which are too steep and too vigorous lateral shoots along the leader are removed in its base. This type of pruning, which promotes fruit bud production and early cropping, reduces vegetative growth of the tree. In the case of good development of the trees after planting ,Â they can be loaded up to 40 fruits in the second growing year, providing a yield of more than 30 tons per hectare. Production in the third leaf can achieve 40-50 t ha-1 and full production, which usually started in the fourth leaf, more than 60 t ha-1can be expected depends on cultivar and growing conditions. Pruning of the mature trees means cutting of the strong watersprouts, the upright shoots and the strong terminal shoots at the top of the tree at their base, remaining only weak fruit-bearing wood. The fruit thinning is regularly applied in modern apple orchards, starting from the second growing year, in order to achieve regular yield and uniform fruit quality.. For this purpose plant growth regulators such as auxins [naphthalene acetic acid (NAA) or naphthalene acetamide (NAAm)] and cytokinin [6 - benzyladenine (BA)] are used. Recently, herbicide metamitron, as a new chemical thinners that at a low dosage reduces photosynthesis and consequently enhances fruit drop are also used. Metamitron exhibited thinning activity when applied to apple fruitlets at the 6 to 15 mm in diameter, or even later, at 20 mm. It can be applied once or twice, depend on the weather conditions in the day of application and three days after.
Working Group 1: Plant Cultivation and Animal Growing Technologies