The humic acids influence on the quantity and quality of table grape varieties under the Absheron peninsula conditions

Abstract

Humates are widely used in viticulture, including ecological viticulture. Humic stuffs benefit the qualitative and quantitative indicators of the grape harvest and can reduce the use of synthetic fertilizers and pesticides. This article presents the results of tests on the foliar application of various doses of the “Rostok” fertilizer in the conditions of the Absheron zone of Azerbaijan on local varieties of table grapes – traditional Tabrizi and a selection variety of Scientific Research Institute of Viticulture and Wine-making Ganjavi, grown in the Ampelographic collection of the institute, located on the Absheron peninsula. Fertilizer was applied in three doses – 0.5; 1.0 and 1.5 liter per hectar. Under the influence of the fertilizer, such elements of yield as the vigor of shoot growth, the number of opened buds, fruitful shoots, the number of berries in a bunch, the weight of a bunch, as well as the sugar content of berry juice increased. Fertilizer application had a positive effect on eliminating signs of leaf chlorosis. No toxic effect on the vegetative organs of the grape plant, on its development, or on the beneficial insect fauna of the vineyard was noted. Based on the data obtained, as well as calculations of economic efficiency, a four-fold application of fertilizer (twice before flowering, once after, once during veraison) at the rate of 1 liter per hectare was recommended for widespread use in wine-growing farms.