Abstract
The aim of evaluations performed in experimental plantings of the Research and Breeding Institute of Pomology Holovousy Ltd. was to verify the effect of covering systems on fruit characteristics – size, weight, firmness and soluble solids content (SSC). The research was focused on evaluation of fruit characteristics in 2017 and 2018 on fourteen cultivars: ´Amid´, ´Cristiana´, ´Early Korvik´, ´Elza´, ´Fabiola´, ´Felicita´, Horka´, ´Justyna´, ´Kasandra´, ´Kordia´, ´Korvik´, ´Tamara´, ´Těchlovan´ and ´Vanda´. The tested cultivars were grown in an IPM irrigated covered orchard. The largest fruit size was recorded for the cultivar ´Tamara‘ with 29.5 mm followed by the cultivar ´Horka‘ with 29 mm and ´Felicita´ with 28.6 mm. The greatest weight was recorded for the cultivar ´Tamara‘ with 12.4 g followed by ´Felicita´ with 12.3 g. The greatest firmness was recorded in fruits of the cultivar ´Amid´ with index 77.5 and ´Tamara´ with index 73.2. High correlation between fruit characteristics was found only between weight and size of fruits (correlation coefficient 0.88). High differences were recorded between years. In 2017, fruits characteristics were higher (size 27.5 mm, weight 10.9 g, firmness 65.3, SSC 19.3 °Brix) while in 2018, fruit characteristics were lower (size 26.5 mm, weight 9.2 g, firmness 59.2, SSC 16.5 °Brix).