Effects of Foliar Biofertilizer Sprays on Nutrient Uptake,Yield, and Quality Parameters of Blaufrankish (Vitis vinifera L.) Grapes

Nowadays the main task of scientists is to find natural ways of improving plant productivity that lead to environmentally friendly agriculture. Biofertilizers have a great potential to achieve this aim but unfortunately there is little information about their application in grape growing in Hungary. For this reason, a foliar nutrition experiment was conducted to investigate the effect of two biofertilizers (an algae product and a biostimulator, containing amino acids) on yield, leaf nutrient concentration, and quality parameters of Blaufrankish grape variety. The study was conducted in 2012 at Noszvaj in northeastern Hungary in a 24-year-old grapevine plantation on cv. Blaufrankish. Treatments (application time and doses) were adjusted to the phenological phases of grapevine. Effect of treatments was monitored by soil and leaf analysis, grape quality measurements, and field observations. Treatments increased the yield but did not affect the fruit quality compared to the control. The applied products significantly increased the bunch weight and the size of berries. Applied biofertilizers had no effect on leaf nutrient concentration. According to our field observations, it seemed that treated vines had larger and greener leaves.