RHYTHMOLOGICAL FEATURES OF THE SPECIES OF SPRING-SUMMERGREEN PHENORHYTHMOTYPE
The enrichment of the regional range of plants with valuable ornamental perennial species assumes the study of their seasonal development as an indicator of adaptability and ornamental effect duration. The seasonal rhythms of 81 species of spring-summergreen phenorhythmotype were investigated at their introduction in Novosibirsk. The following features were revealed: a long growing season, mainly early spring growth, flowering from late spring to mid-summer, and natural or forced vegetation end. More than a half of the species (53%) grow in the second or third ten-days of April, while few species (11%) have the late start of the growing season. The period before flowering varies from 8-15 days in spring-flowering species up to 3 months or more in late flowering species. Most of the species (88%) bloom in the period from late spring to mid-summer. The growing season of the spring-summergreen species averages to 143 ± 1 day, varying within 104-167 days. Their growing season ends naturally regardless of the weather conditions or forcedly under the influence of autumn frosts. Considerable heterogeneity of sping-summergreen phenorhythmotype in terms of the rate of seasonal development was revealed. Its domination among the long growing perennial species in West Siberia shows the greatest compliance of this type to the climate of the region. Due to a long growing season, various flowering terms and duration, the spring-summergreen species create ornamental effect from May to September.