The experiment was carried out near Szczecin (Poland), in 2008 - 2009. The object of the study was the first Polish cultivar of dessert grapevine - Danmarpa Polonia. The experimental factor was spraying of biostimulator Biochicol 020 PC. Two concentrations of Biochicol were applied - 1% and 4%. Spraying was performed from flowering to fruit harvest. The following parameters of the investigated variety were determined: the yield of fruit, number and size of clusters, firmness, mass and diameter of an individual fruit, the content of L-ascorbic acid, total acidity in fruit and soluble solids content. The degree of infection of leaves and fruit by fungi of downy mildew (Plasmopara viticola) was also observed. The results were put to a one-factor analysis of variance. The significance of differences between the averages was defined by Duncan`s test at a=0.05. Biochicol influenced the yield, number and size of clusters, and the number of fruit in clusters, whereas the length of clusters was not affected 1% concentration of Biochicol, significantly decreased infection by downy mildew and total acidity in fruit and increased the content of L-ascorbic acid and soluble solids in fruit.
The influence of biostimulator biochicol 020 PC on quantity and quality of yield of grapevine cultivar Danmarpa Polonia