Realization of the potential productivity of black-currant under the conditions of cryolithozone

Abstract

Productivity components, calculated and actual productivity, winter resistance, ability to ear­ ly maturing were studied for the varieties of eight genetic groups of black-currant during the years 1990– 2015. It was revealed that the potential productivity of the hybrids of the Siberian sub-species of blackcurrant Ribes nigrum ssp. sibiricum E. Wolf and R. dikusсha Fischer ex Turczaninow was the highest (511,4 centners/ha for Dubrovskaya, 467,1 centners/ha for Seyanets Golubki). The actual productivity was less than 10 % of the potential level during the first years of cultivation. The productivity of local species and varieties was lower (242,7 centners/ha – Sardaana variety), its realization reached 48 %. The main reasons of low actual productivity are insufficient winter resistance due to the genotype, and the lack of heat during blossoming and fruiting; as a consequence, up to 45 % of the yield is lost. The local species of black-cur­ rant, as well as the varieties of the 4^th, 5^th, 8^th genetic groups, are winter-resistant (winter resistance: 1 point), the varieties of the Siberian sub-species are characterized by winter resistance of 2 points. Gen­ eral warming of the climate in Central Yakutia caused an increase in actual yield. Realization of the potential productivity increased to 33–40 %. A strong positive correlation between the productivity and the number of berries in a bunch was established (r = 0,803, P = 0,04), and the mass of a berry (r = 0,811, Р = 0,05).