COMPARATIVE STUDY ON THE RESPONSE OF SEVERAL PLUM CULTIVARS IN CENTRAL TRANSYLVANIA CONDITIONS, ROMANIA

In the conditions of central Transylvania, Romania, five plum cultivars were studied, with different fruit ripening: earlier (Tuleu timpuriu), semi-earlier (Reine Claude d’Althan), medium (Valor), semi-late (Vinete de Italia), late (Vinete romanesti). Tuleu timpuriu and Reine Claude d’Althan distinguish for their high productivity (over 20 kg of fruits per tree), Valor for the large fruits (with the average of 68.0 g, but with a lower quality), Vinete romanesti and Vinete de Italia for their extreme susceptibility to the most important diseases (Polystigma rubrum and Plum-pox virus). One of the traditional plum cultivars from Romania, still largely spread in Transylvania, Vinete romanesti, which is very appreciated, both for its fruit taste and for the alcohol distillation obtained, confirmed its estimation due to fruit quality. Vinete romanesti has small fruits compared to the actual commercial requirement of the fresh plum, low productivity, and it is extremely susceptible to Plum-pox virus and Polystigma rubrum attack, thus the cultivar unfulfills the conditions for modern cultivars. In addition, the cultivar can be used in plum breeding, as genitor for quality (taste of fruits) and the low vigour of trees. The high values of the heritability coefficient, in a broad sense, applied to the majority of the analyzed traits, suggest that, through an adequate selection of the genitors, descendents, which can present valuable traits from the parental form, can be obtained and thus, new cultivars can be selected. Vinete romanesti can be used in plum breeding, as genitor for quality (taste of fruits) and the low vigour of trees.