Features of the anatomical structure of <i>Juniperus foetidissima</i> Willd. needles in the conditions of the Crimean Peninsula

Abstract

Currently, the natural flora of Crimea includes 5 species of junipers, the smallest of which is J. foetidissima. The anatomical structure of needles is an important diagnostic feature that allows one to assess the intraspecific variability of rare species and the stability of their tree stands. In the conditions of the Crimean Mountains, extensive intercellular spaces are clearly visualized on a cross section of J. foetidissima needles. Such a feature of the anatomical structure of the needles of the species under study has not been described previously. The proportion of intercellular spaces varies from 5,36% to 20,89%, on average, their area is 0,018 ± 0,002 mm². Intercellular spaces are located in the central part of the needles between the vascular bundle and the resin canal, and sometimes on both sides of it. The mesophyll is very loose here. Along the periphery, the dense mesophyll consists of 3–5 rows of elongated oval cells. In addition, there is one fairly large resin channel. Its area can occupy up to 15% of the total cross-sectional area of the needles. The correlation dependences of the parameters of the anatomical structure of the needles of J. foetidissima are similar to those of J. deltoides, which, in turn, has a needle-shaped needle type. The drought resistance coefficient of the studied species made it possible to classify them as mesophytes.