Different Nutrition Approaches for Raspberry (Rubus idaeus L.) cv. 'Himbo-Top' (`Rafzaqu'): Influence on Productivity, Fruit Quality and Storage Potential

A field trial was conducted to assess the effects of different approaches of plant nutrition (from extensive >> low-input << to intensive >> luxury << nutrition program) of raspberry (Rubus idaeus L.) cv. 'Himbo-Top' (`Rafzaqu') on productivity, yield quality and storage potential. The experiment was based on the amount of applied nitrogen and the use of a biostimulant with addition of silicon ( Si). Different water-soluble crystalline fertilisers were used at different growth stages of the plants with the use of a fertigation system, while the biostimulant was applied on leaves. The experiment consisted of four different treatments: 20 kg N/ha in total in one application, 60 kg N/ha in total in multiple applications, 80 kg N/ha in total in multiple applications and 80 kg N/ha in total in multiple applications in combination with biostimulant. The results show that higher rate of nitrogen results in an increased mass of individual fruit, while it does not affect the total yield. On optimally prepared soil with approx. 3 % of organic matter, the use of nitrogen amounts higher than 60 kg N/ha significantly reduces fruit quality in terms of soluble solids content and sensory value. It also significantly reduces the storage potential due to increased microbial activity (mould appearance). The efficiency of silicon containing biostimulant seems to be limited and cannot compensate the negative effects of higher rates of nitrogen on fruit quality and storability.