DYNAMICS OF REPRODUCTION OF GRAPE ROOTSTOCKS IN THE SYSTEM IN VITRO

In connection with the extension of areas under vineyards, it becomes necessary to use rootstocks, resistant to certain soil and climatic conditions (high content of active lime and salts in the soil, drought). Growth of the assortment of rootstocks available for propagation is one of the most important strategies of domestic nursery farming development, along with the production of improved planting material and better performance of its quality indicators. Today it is important to optimize clonal micro-propagation technology for promising grape rootstocks in order to increase net reproduction while maintaining the genetic identity of planting material. The purpose of the work was to study the dynamics of morphogenesis of grape rootstocks in the system in vitro to optimize the technology of clonal micro-propagation, taking into account the genetic specificity of particular genotypes. The study materials were the in vitro plants of grape rootstocks: Fercal clone 242, Ruggeri 140, and Gravesac (clones 11 and 12). The methods accepted in biotechnology and developed in the Breeding Department of the Institute Magarach were both used in the process of research. Cultivation was carried out on PG medium supplemented with NAA (α-naphthylacetic acid) 0.05 mg/l. The results showed that the dynamics of morphogenesis of rootstocks Ferсal clone 242, Gravesac clone 11 and Gravesac clone 12, analyzed on the basis of net propagation, did not differ significantly by varieties, with the exception of the second passage. The study of morphogenetic potential of Ruggeri 140 rootstock bud made it possible to reveal the dependence of net propagation on the line, it was especially noticeable in the first passage. Separate lines showed high net propagation in the second passage. The average indicator value for all lines was 2.59. In general for all rootstocks, similar results were obtained in successive passages, indicating a tendency for net propagation to be decreased. In order to increase the efficiency of technology, it is necessary to optimize the conditions of cultivation for industrial propagation, taking into account the genetic characteristics of every rootstock.