Коренева система відсадків яблуні 54-118 за обробки регулятором росту КАНО / The root system of apple-tree layers 54-118 treated with the growth regulator NAA

Abstract

Обробка основи пагонів маточних рослин клонової підщепи яблуні 54-118 10% водним розчином калійної солі α-нафтилоцтової кислоти з нормою витрати 2,0 мл/л (перед першим підгортанням) сприяє збільшенню числа і довжини коренів та зони окорінення. / The article is devoted to the investigation of the number, root length and rooting zone, depending on the treatment of the bases of shoots of the mother plants of apple-tree clonal rootstock 54-118 type with 10% aqueous solution of potassium salt of α-naphthylacetic acid (before the first hilling). The quality of the clonal rootstocks is largely determined by the sufficient number of roots and the length of the rooting zone. Rooting is stimulated by growth regulators, in particular by treatment with indolyl-butyric acid and alpha-naphthylacetic acid. Rooting is improved by the use of potassium salt of alpha-naphthylacetic acid (NAA), a compound of auxin nature, which increases the ratio of auxins to cytokinins, promoting the formation of accessory roots. The treatment of the above-ground part of the mother plants of clonal apple rootstocks with α-naphthylacetic acid increases the output of standard layers, and also increases the number and length of roots. The purpose of this study is to improve the quality of the root system and the productivity of the mother plantation of clonal rootstock 54-118 by treating the base of the shoots with the growth regulator NAA. In 2012–2014 the research was conducted in the training and production department of Uman National University of Horticulture. In 2010 the mother plantation of rootstock 54-118 was laid down with the virus-free plants in the way of horizontal layers with the scheme of planting 1.4 x 0.33 m and hilling with sawdust. The soil of the experimental plot was black earth podzolized heavy loam with humus content of 3.5%; pH of the salt extract is 5.9. There were 10.8 mg/100 g of easily hydrolyzed nitrogen (according to Kornfield), 11.9 – mobile phosphorus and 10.1 mg/100 g of exchangeable potassium (according to Chirikov) in the arable soil layer. The soil density is 1.18–1.20 g/cm3, the lowest field moisture capacity is 30.3% and 28.6% in arable and subsoil layers, respectively. The relief of the experimental plot was flat with an insignificant southern slope; the subsoil waters were located at a depth of 10–15 m. The basis of the aboveground part of the mother plants was treated before the first hilling, which was carried out at a shoot height of 20 cm. An aqueous solution with 10% application rate of potassium salt of α-naphthylacetic acid from 0 (control) to 2.5 ml/l (0.5 ml/l step) was used at a flow rate of 1000 l/ha of working solution. The replication of the experiment was fourfold with a randomized arrangement of the plots and at each registration plot (the hilling with sawdust of deciduous species up to a height of 40 cm) there were 10 accounted/recorded mother plants. Recordings and observations were conducted by generally accepted methods. The total root length on the layers was determined after separation from the mother plants, and the length of the rooting zone was also taken into account. The statistical processing of the results was carried out by the dispersion and correlation analysis of program "Statistica". It has been established that treatment of the base of shoots of mother plants with an aqueous solution of 10% potassium salt of α-naphthylacetic acid with a rate of 2.0 ml/l (before the first hilling) improves the parameters of the root system of rootstocks 54-118 significantly. With the increase in the NAA application rate in the interval 0.5 ... 2.0 ml/l, the number of roots increases by 11.7–13.9%, the total length of the roots on the layer – by 23.7–28.7%, the length of the root – by 9.8–14.3% and the rooting zone increases by 6.3–7.0%. At the same time, at a rate of 2.5 ml/l of 10% NAA, the parameters of the root system are 2.6–9.9% less than at a rate of 2.0 ml/l, which is described by equations of the form y = a + bx + x2 (ηyx = 0.83 ... 0.96). The change in the parameters of the root system by 52–90% is determined by the NAA-treatment of the base of the shoots of the mother plants.