Acclimation of photosynthetic apparatus of leaves and reproductive sphere of Dryas octopetala L. when introduced into the middle zone of Russia
E. V. Chernyaeva, N. G. Kuranova, V. P. Viktorov
Moscow Pedagogical State University, Moscow, Russia
Keywords: Dryas octopetala, introduction, acclimation, photosynthetic pigments, specific leaf area
Abstract
The rhythm of development, seasonal dynamics of photosynthetic pigment content, specific leaf area (SLA), water content, and the rate of accumulation of dry matter in D. octopetala leaves of spring and autumn generations under introduction conditions were studied. The obtained results were compared with similar indicators in the natural habitat according to the literature data. It was found that the restructuring at the cellular-tissue level led to an increase in the specific leaf area by 3.7-4 times. The leaves of the spring generation have increased the life span, the duration of vegetation, the amount of chlorophylls and carotenoids. In the leaves of the autumn generation, these indicators have not changed. The leaves of the spring and autumn generations contained 7.89 mg∙g-1 and 3.32-6.48 mg∙g-1 of chlorophyll, respectively. The structural and functional characteristics of the pigment apparatus of the leaves of spring generation corresponded to the high intensity of photosynthesis, the autumn - low intensity. Under the conditions of introduction, the former showed ecological plasticity and a high ability to acclimation changes, the latter - a conservative, stenobiont adaptation strategy. The growth rates of D. octopetala remained at the characteristic level for the species. The number and mass of diaspores per flower, the length of peduncles increased by 2.2 and 2.8 times, respectively. Germination over the entire observation period was low, 2.32 ± 0.7 % over a six-year observation period.
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