Darius Kviklys, Nomeda Kviklienė and Nobērtas Ūselis
Seven apple clones of cv. ‘Jonagold’: ‘Red Jonaprince’, ‘Jonagold Boerekamp’, ‘Jonagored Supra’, ‘Jonaveld’, ‘Jonagold DeCoster’, ‘Jonagold Novajo’ and ‘Jonabel’ were tested at the Institute of Horticulture in Babtai in 2003-2011. Significant differences among cv. ‘Jonagold’ clones were recorded in yield, fruit quality parameters and winter hardiness. The highest total yield was recorded for cvs. ‘Jonagold Boerekamp’ and ‘Red Jonaprince’, the lowest for cv. ‘Jonagold Novajo’. Average fruit weight of cv. ‘Jonagold Novajo’ was significantly lower. ‘Red Jonaprince’ fruits had the best colouration. ‘Jonagored Supra’ fruits had the best appearance according to the test panel. During winter 2009-2010, 30% of ‘Red Jonaprince’ trees suffered frost damage. No losses were recorded for ‘Jonagored Supra’. During the experiment tree losses due to frost and disease damages were 25-60% and depended on the clone.
Juozas Lanauskas, Darius Kviklys, Nobertas Uselis and Loreta Buskienė
Twenty plum cultivars on Myrobalan (Prunus cerasifera Ehrh.) seedling rootstock were tested in 2012–2017 at the Institute of Horticulture of the Lithuanian Research Centre for Agriculture and Forestry. Plum trees were spaced at 4.5 × 2.5 m and trained as spindles. Orchard floor management included frequent mowing of grass in the alleyways with herbicide strips along tree rows. ‘Duke of Edinburgh’, ‘Kijevas Vēlā’, ‘Dąbrowicka Prune’, ‘Čačanska Najbolje’, ‘and ‘Štaro Vengrinė’ cultivars were the most vigorous plum trees at the end of 6th year. Their trunk diameter achieved 92–96 mm. ‘Valor’, ‘Queen Victoria’, ‘Herman’, ‘Čačanska Najbolje’, ‘Favorita del Sultano’, ‘Ave’, and ‘Jubileum’ cultivars had the lowest trunk diameter — 72–78 mm. The highest cumulative yield of four fruiting years was recorded for ‘Kometa’ and ‘Violeta’ cultivars, respectively, 43.0 and 46.5 kg/tree. ‘Favorita del Sultano’, ‘Rausvė’, and ‘Kijevas Vēlā’ produced the largest fruits — 52–60 g. The smallest fruit occurred on ‘Dąbrowicka Prune’ and ‘Herman’ cultivars, respectively, 22 and 25 g. ‘Dąbrowicka Prune’ had the highest soluble solids content (SSC) — 19.5%. The least SSC was recorded in ‘Kometa’, ‘Violeta’ and ‘Herman’ fruits — 10.6–11.8%. ‘Renklod Rannij Doneckij’, ‘Čačanska Najbolje’, and ‘Valor’ cultivars had the highest fruit flesh firmness.
Darius Kviklys, Mindaugas Liaudanskas, Jonas Viškelis, Loreta Buskienė, Juozas Lanauskas, Nobertas Uselis and Valdimaras Janulis
The trial was carried out at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in 2013-2015. Cv. ‘Auksis’ was tested on 12 rootstocks: B.396, B.9, M.9, M.26, P 22, P 59, P 61, P 62, P 66, P 67, PB.4, and Pure 1. Accumulation of phenolic compounds depended on fruit yield and average fruit weight. On average, significantly lower concentration among rootstocks occurred when apple trees had abundant yield and fruits were smaller. On average chlorogenic acid constituted 50% and total procyanidins 28% of total phenols in ‘Auksis’ fruits. Flavonoid concentration most depended on rootstock and the highest variation was recorded. More than 50% difference occurred between the highest total flavonoid concentration in apples on PB.4 and the lowest on M.9 rootstocks. Low variability of total procyanidin concentration among rootstocks was observed. Differences between the highest and lowest concentration was 15%. Total concentration of phenolic compounds differed among rootstocks by 29-35% depending on the year. Differences in accumulation of phenolic compounds depended on rootstock genotype but not on yield or fruit weight. PB.4 and P 67 rootstocks had the highest, and M.9, P 62 and M.26 had the lowest concentration of total phenol in ‘Auksis’ fruits