The effect of drought on the photosynthetic apparatus condition in some <i>Ficus Carica</i> cultivars

Abstract

The results of field and laboratory studies of drought tolerance in some Ficus carica cultivars of various origins are presented. It has been found out that under the conditions of the Southern Coast of the Crimea, the cultivar Sabrutsiya Rozovaya is characterized by high drought tolerance. Low resistance to dehydration was noted in the cultivars Vladimirska Krupna, Pomoriyskiy 6, Franziana Biella. It was revealed that in August, a decrease in water holding capacity occurs in all the studied cultivars. Using Chlorophyll Fluorescence Induction (CFI) method, an integrated assessment of the photosynthetic apparatus in the leaves of Ficus carica cultivars under conditions of simulated wilting is given. It has been demonstrated that drought is the cause of decrease in the photosynthesis light phase efficiency, the part of chlorophyll involved in the transfer of energy from light harvesting antenna complexes to reaction centers and the enhancement of non-photochemical photo quenching. A resumption of photosynthetic activity was observed with the normalization of leaf water supply in the resistant cultivar Sabrutsiya Rozovaya and the medium-resistant cultivar Iyulskiy. In the cultivars characterized with low drought tolerance, Vladimirska Krupna, Pomoriyskiy 6 and Ranniy iz Sozopol, the resumption of the water content in leaves was followed by a decrease in the variable fluorescence and photochemical activity of PS 2, which indicates further stress development in these cultivars and high sensitivity of their photosynthetic apparatus to dehydration. During the fruit ripening, on the background of water holding capacity decrease, water deficit in leaf tissues within 20-25% results in irreversible disturbances in the photosynthetic apparatus activity in Ficus carica cultivars that is proved by a decrease in the viability index below the vitality norm and may adversely affect the preparation of plants for transition to a state of rest.

Features of the water regime and photosynthesis in hybrid forms of cherry plum under the dry wind season conditions

“…3). Выявленные различия могут быть связаны как с индивидуальными особенностями гибридных форм (сроки жизни листа, его морфофизиологические характеристики), так и с реализацией физиолого-биохимических защитных механизмов (Yakovleva et al, 2005;Gubanova et al, 2019).…”