Flowering peculiarities of the genus Crataegus plants in the Kola Subarctic conditions

УДК 582.734.3:581.543(1-924.16)

Abstract

The article results of phenological observations of plants of 12 introduced species from the genus Crataegus L. growing on the territory of the experimental site of the Polar-Alpine Botanical Garden in Apatity. The morphometric parameters of flowers and inflorescences were studied, the flowering score, the duration of flowering and the content of flavonoids in flowers were determined. The influence of the sums of positive temperatures on the dates of the onset of flowering phenophases is analyzed. Flowering of hawthorns in the Kola Subarctic occurs in late June - early July. The flowering period of hawthorns ranges from 5 to 11 days. High flowering scores were determined for C. flabellata, C. maximoviczii and C. pinnatifida. The remaining species are characterized by medium and weak flowering. C. dahurica, C. russanovii and C. maximoviczii have the largest inflorescences, the largest flower diameters are characteristic of C. dahurica, C. russanovii and C. douglasii. In all species, the hyperoside content was not lower than the norm recommended by the State Pharmacopoeia. The species with the lowest requirements for heat accumulated at the beginning of the flowering period include C. flabellata and C. х schroederi, which is relevant in the climatic conditions of the Subarctic.