Адаптация сезонных ритмов развития на примере дендроколлекций ФНЦ агроэкологии РАН

Abstract

Assessment of the success of adaptation of woody plants to soil and annual changes in seasonal meteorological conditions of the arid growing region based on the method of phenological observations allows us to identify the synchronicity of the development of vegetative and generative organs of cultivated plants. The years of experimental materials (for a 20-year period: 1979, 1989, 2019) seasonal development of 47 woody plant species growing in areas with brown soils in dendrological collection Nizhnevolzhsky station on selection of tree species, branch of Federal scientific center of agroecology of the Russian Academy of Sciences (Kamyshin, Volgograd oblast). It is revealed that each species has its own annual cycle with a certain sequence and duration of periods of growth and development, reproduction, etc. The conjugation of prophases with the seasonal rhythm of climatic parameters and important prophases with each other is established, and the frequency characteristic of prophases of seasonal development is given. Plant biorhythms are associated with anatomical, morphological, physiological, and biochemical characteristics and properties that affect the degree of adaptation to environmental factors. The phenological patterns of trees and shrubs development necessary for predicting their prospects for protective afforestation and landscaping under the influence of stress factors and climate change are established. Based on the analysis of long-term (60 years) phenological observations, it was found that the variability of onset dates within the phase is significantly lower than between the development phases. This is consistent with the energy needs of phenophases of development in ontogenesis and species affiliation and geographical origin. The revealed regularities between plant biorhythms and seasonal changes in climatic factors in the conditions of the Volgograd region. In most species, leaf budding begins and reaches its maximum when the sun shines for more than 13.5 hours a day and the average daily air temperature is between 5-10-15°C. The maximum prophase of the beginning of flowering in woody plants is the duration of sunshine 14-16 hours a day at an air temperature within 10-18°C. The end of flowering is shifted a decade later at approximately the same parameters of solar radiation and air temperature. The foliage of all plants is laid in three decades of may — this is 15-16 hours of sunshine and the air temperature is 15-21 °C. The end of the growth of runs occurs during the period of the year when solar radiation reaches a maximum of 16 hours per day and the air temperature is approaching the maximum of the average daily air temperature of + 24 °C. In a series of studied prophases, there are certain relationships: each subsequent one begins at the end of the previous one; sometimes it is possible to overlap the prophases of development (vegetative and generative organs).