GENETIC GAIN ACHIEVED IN PLUM BREEDING PROGRAMS IN ROMANIA
Genetic gain in the case of European plum grown in Romania was a major concern for the breeding programs from 1951 to 2010. The breeding programs produced 30 cultivars and 13 rootstocks that have been named. Plum growing has historical tradition and has a 45% share of the fruit tree production in Romania. Initially, the cultivar assortment was formed by local cultivars which have small fruits and used in proportion of 80% for alcohol production, only 20% of the production being used for fresh consumption, dried and processed as jam or marmalade. Plum quality and productivity issues influenced cultivar and rootstock breeding programs. The most obvious genetic gain was obtained for size and weight of fruits. The old autochthonous cultivars had small fruits (20-25 g); the bred cultivars have an average fruit weight of 48 g (from 35 to 70 g). The achieved genetic gain was 190% in average. The new cultivars yields varies from 15 to 26 t/ha, that is 8 to 16 t/ha higher than the case of old cultivars (162-214%). Also, the new cultivars have firm flesh and non-adherent to the stone. The majority of the old plum cultivars had adherent stone to the flesh and rarely firm flesh (Tuleu Gras, Vinete Româneşti). Very important genetic gain in plum cultivar breeding was the improving of Plum pox resistance as it is the case of Andreea, Flora and Agent. Plum culture in Romania is spread in different ecological areas, on various soils. As result, new rootstocks of low vigor and with high adaptability to different soil conditions and with clonal or seed propagation. The rootstocks that can be used for high density plum orchards (over 1000 trees/ha) proved to be: Oteşani 8 and Mirobolan Dwarf. Oteşani 8, Miroval, Corval, Oltval, etc. are clonal rootstocks.
Botu, M., Achim, G., Botu, I., Preda, S. and Vicol, A. (2012). GENETIC GAIN ACHIEVED IN PLUM BREEDING PROGRAMS IN ROMANIA. Acta Hortic. 968, 47-53
plum, plum breeding, cultivars, genetic gain