The influence of growth regulators on the achieving of high productions from the Kordia cherry variety on the MaxMa 14 rootstock

Abstract

The object of the researches were cherry trees of the Kordia variety grafted on the MaxMa 14 rootstock. The research was carried out during 2021. To study the effect of the growth regulators Auxiger (1-naphthylacetamide (1-NAD - 1.5 g/l) and 1-naphthylacetic acid (1-NAA - 0.6 g/l)) and Gibbera, SL (gibberellins, 10 g/l mixture of GA4+7) on the degree of fruit setting, development processes, fruit production and economic production efficiency, the following treatment variants were experimented: 1. Control – no treatment; 2. Auxiger, 0.7 l/ha; 3. Gibbera, SL, 0.25 l/ha; 4. Gibbera, SL, 0.5 l/ha. The growth regulator Auxiger was administered only once, during the period of intensive fruit growth, when their diameter reached 12-13 mm (14.05.2021), and Gibbera, SL in three rounds. The first treatment at the end of the flowering phase (26.04.2021), and subsequent two at an interval of 7-10 days, (05.05.2021) and (14.05.2021), respectively. In the reference period it was established that the degree of fruit binding, development processes, higher fruit productions was recorded when treated with the growth regulator Gibbera, SL in a dose of 0.5 l/ha.