Summer- and autumn-fruiting raspberry quality as influenced by the harvest date

During a three-year study conducted at the Experimental Garden of the University of Warmia and Mazury in Olsztyn, the yield and quality of raspberry fruit of the summer-fruiting cultivars ‘Benefis’, ‘Laszka’ and the autumn-fruiting cultivars ‘Polesie’, ‘Polka’ and ‘Popiel’ were evaluated. The raspberry harvest was carried out on three carefully selected dates, i.e. for summer-fruiting cultivars: in the first, second and third decades of July and for autumn-fruiting cultivars in the second decade of August and the first and third decades of September. The highest yields were obtained from the cultivars ‘Polesie’ and ‘Polka’. The fruit of the tested cultivars collected during the third term had significantly lower masses. The highest contents of dry matter in fruit were recorded for ‘Polka’ and of organic acids for ‘Popiel’ and ‘Benefis’. The fruit harvested in the second and the third term had a higher content of dry matter.