Evaluation of non-traditional plum cultivars for growing in the Czech conditions

The current trend of climate change has led fruit growers to seek solutions stabilizing yields and ensuring profitable production. Furthermore, it is necessary to take into account the qualitative requirements of the market, such as the emphasis being placed on bio-sustainable cultivation and fruit production. This study deals with the possibility of growing cultivars from species not typical for fruit growing in the Czech Republic. These cultivars are derived from Prunus salicina, Prunus cerasifera and various hybrids. A total of 29 interesting cultivars and two control cultivars (‘Stanley’ and ‘Čačanska Rana’) were included in the experiment. Phenological data, pomological and qualitative characteristics were evaluated. The cultivar with the largest fruit was the Japanese plum ‘Aphrodite^®’, with an average fruit weight of 53.6 g, followed by ‘Fortune’ with 48.5 g, and the interspecific hybrid ‘Čornyj Princ’ with 45.7 g. The highest refraction was recorded in the European plum ‘Stanley’ (22.7%) and some Asian plums such as ‘Wan Hong’ and ‘Burbank’ (22.3 and 21.6%, respectively). Surprisingly, the highest content of titratable acids was found in the cultivars ‘Lavina’ (40.19 g 100 g^‑1) and ‘Kleopatra’ (36.98 g 100 g^‑1) (both of a myrobalan origin) and the Asian plums ‘Aphrodite’ (34.18 g 100 g^‑1) and ‘Zurna’ (33.62 g 100 g^‑1) (both interspecific hybrids P. salicina×P. cerasifera). On the other hand, the lowest content of titratable acids was observed in ‘Stanley’ (7.69 g 100 g^‑1) as the control cultivar. Vitamin C content is a very important parameter for human health. The results again show significant variability among the assessed cultivars, with the highest values of vitamin C measured in both interspecific hybrids from our breeding work ‘SLE2014/1’ and ‘SLE2014/2’ (447.1 and 328.9 mg 100 g^‑1, respectively). Similarly high vitamin C contents were measured in other interspecific hybrids as well. On the contrary, European and Japanese plum cultivars had less vitamin C (on average 15.7 and 26.7 mg 100 g^‑1, respectively). Another important parameter for consumers is the taste of the flesh. The results show that the European plum dessert cultivars had the best taste, followed by greengage cultivars, and cultivars derived from big fruit myrobalans and their hybrids. Surprisingly, the cultivars of Asian plums and interspecific hybrids had the lowest taste ratings.