The seed production and quality of Pinus sylvestris seeds in forest plantations on the Crimean yaylas has been studied. The dynamics of biometric indicators of cones and seeds by year and in connection with the peculiarities of growing conditions has been characterized. Significant differences in the quality of seeds of P. sylvestris trees have been revealed in terms of the level of germination energy. It has been shown that, along with the temperature regime, a significant impact on the effectiveness of P. sylvestris reproduction processes is exerted by air humidity and the nature of precipitation, as well as the dynamics of air mass movement, since the success of pollination is determined by the quantity and quality of pollen that has reached the female reproductive structures. Based on the analysis of weather phenomena and the dynamics of seed quality, it has been found that the level of seed germination is best reflected by an integrated index that takes into account the combined effect of several factors – the dryness index. In addition, the results of the analysis allowed us to conclude that the efficiency of the pollination process of female cones of P. sylvestris under yayla conditions is most likely influenced by the number of hours of sunshine. The germination energy and seed germination differ not only within the studied plantations, but also depending on the year of study. During the observation period, the forest plantations of the Ai-Petrinskaya Yayla have produced the highest quality seeds. In 2014, in the plantations with a density of 0.5, the seed germination rate was 74.5±2.2 %. The lowest level of germination energy and seed germination has been noted in artificial plantations of P. sylvestris on the Tirke Yayla; in 2012, these indicators here amounted to 15.2±0.7 and 46.2±2.1 %, respectively. In general, the development of the generative sphere of P. sylvestris in artificial plantations on the Crimean yaylas is quite effective. Based on this, a conclusion has been made that the growing conditions on the yaylas are favourable for the implementation of the initial stages of the ontogenesis of the species.
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