MODIFICATION VARIABILITY OF INTRODUCED PHLOX PANICULATE CULTIVARS IN THE CONDITIONS OF THE ALTAI OB REGION

In the weather conditions of 2015–2023, 17 fall phlox cultivars (Phlox paniculata L.) from the collection of the Federal Altai Scientific Centre for Agrobiotechnology were studied. The aim of the research is to evaluate the modification variability and propensity to direct and reverse clone mutations of Ph. paniculata cultivars. The diameter of the flower, depending on the cultivar, varied from 1.5 to 3.5 cm. Five cultivars are small-flowered, one lacks a corolla, the rest are classified as medium-flowered. The variation in the flower diameter over the years ranged from 2 % (‘Swizl’) to 9 % (‘Jeff's Blue’, ‘Miss Elie’, ‘Sherbet Cocktail’). Inflorescence size and peduncle height varied over the years from 2 and 4 %, respectively (‘Fancy Feelings’) to 32 % (inflorescence height in ‘Miss Elie’, ‘Natural Feelings’ and shoot height in ‘Areole’). Within favorable weather conditions in 2017, plants had the highest biometric values of indicators. The cultivars ‘Elizabeth’ and ‘Candy Twist’ were severely affected by fungal diseases, as a result they were dropped from the collection. In the hot year 2020, when the sum of active air temperatures exceeded the norm by 521 о C, the formation of flowers with a jagged edge of petals was observed on the cultivars ‘Jeff's Blue’ and ‘Swizl’. The feature was preserved in subsequent years. Reverse mutations were noted in the cultivars ‘Midnight Feelings’, ‘Fancy Feelings’ and ‘Mishenka’, ‘Twister’ in the 6th year of cultivation. In the cultivars ‘Pure Feelings’ and ‘Natural Feelings’, inflorescences with larger petals appeared in the 8th year. Cultivars ‘Yozhik’, ‘Peppermint Twist’, ‘Picasso’ and ‘Sherbet Cocktail’ did not show reverse or modification variability.