Preventive evaluation of drought resistance of apple varieties and hybrids

Abstract

In 2020, the central area of the Republic of Moldova was subjected to a terrible drought. The collection was established in the years 2007-2009, M26 rootstocks, and the selection orchard in the years 2009 - 2011 with planting distances of 4 x 1.5 and 4 x 0.75m, respectively. The 1878 hybrid plants and 203 cultivars, species and elites including 162 genotypes with genetic resistance to apple radish and 41 non-resistant were observed. The assessment of the reaction of the plants was carried out by scoring according to the scale 1-6 where: - 1 – no attack ... 6 - very strong attack, over 80% of the leaves have fallen and the rest are yellow, wilted and twisted. Precipitation in 2019-2020, in the months of October-April, was 60% less than normal. Average monthly temperatures between October 2019 and September 2020 were 3-5% higher. The observations were carried out between September 17-23, 2020 until the rains intervened. Data processing was performed in Excel using one-way analysis of variance without repetitions with the determination of partial differences between hybridization combinations and the level of heritability, H2%. A very weak reaction was observed in the trees of the Dalinred, Florina and Corelita varieties, weak in Nova Easygro and Generos, medium in the trees of the Priam and Dalinbel varieties and strong in Goldrush, Coredana, Coredar and Romus 2.