BIOMETRIC INDICES OF POLLEN FROM NATURAL POPULATIONS OF <i>PINUS BRUTIA</i> VAR. <i>PITYUSA</i> (PINACEAE) OF THE CRIMEAN MOUNTAINS

Abstract

The study of biometric characteristics of Pinus brutia var. pityusa pollen was carried out in natural populations of P. brutia var. pityusa in the Crimean Mountains. The pollen was collected during the period of its free flight on sample plots along four hypsometric profiles. In the western part of the southern macroslope of the Main Ridge of the Crimean Mountains on Cape Aya in the Ayazma tract, 3 sample plots were laid at altitudes of 50–290 m above sea level, in Batiliman – 2 plots, at altitudes of 50 and 120 m above sea level; in the eastern part of the macroslope, 3 plots were laid on Karaul-Oba Mt. at altitudes of 40–120 m above sea level, and in the Novyy Svet tract – 2 plots at 50 and 100 m above sea level. Biometric analysis of pollen grains was carried out on temporary acetocarmine slides using generally accepted methods. The results of the study showed that an average size of the pollen grain of P. brutia var. pityusa in natural populations of the Crimean Mountains varies within the following ranges: total grain length from 81.5 to 88.5 μm, the length and height of the pollen grain body 52.2–59.4 μm and 47.8–53.4 μm, respectively, and the length and height of the air sac 40.0–43.0 μm and 25.5–30.4 μm, respectively. The smallest pollen is formed in coastal stands. In the plantations of P. brutia var. pityusa in the western part of the Crimean Mountains, a decrease in the length and height of the air sacs was noted. It was revealed that the indices characterizing the ratio of individual structural elements of the pollen grain, namely γ – the ratio of the body length to the height of the air sac of the pollen grain, δ – the ratio of the body height to the height of the air sac, and Θ – the ratio of the body length to the length of the air sac, allow to analyze aerodynamic properties of P. brutia var. pityusa pollen. The decrease in γ, δ, and Θ pollen indices in the plantations of Ayazma and Batiliman reflects a decrease in the efficiency of its aerial distribution, which has a negative effect on the level of heterogeneity of natural populations in these territories.