Morphological and anatomical changes in leaves of some Ficus carica L. cultivars damaged with viral diseases

V.A. Brailko, I.V. Mitrofanova, Yu.V. Plugatar, S.V. Chelombit, O.V. Mitrofanova, S.N. Chirkov
Ficus carica L. (family Moraceae) is valuable highly productive early subtropical plant, with the fruit of high calorie and diet value. At the same time, in many fig cultivation areas infection with Fig mosaic virus, Fig leaf mottle-associated virus-1, Fig leaf mottle-associated virus-2, Fig latent virus-1, Fig badnavirus-1 and others was noticed. Monitoring studies in collection plots on the south of Russia allowed us to identify a number of cultivars affected with viral diseases, and presented studies give the analysis for four of them: ‘Pomoriyskiy’, ‘Medovyiy’, ‘Sabrutsiya Rozovaya’ and ‘Smena’. The percentage of leaves with clear symptoms was 10-30% of the whole tree crown. At the same time, mosaic chlorosis and leaf folding were localized along the veins and at the base of the leaf. Morphometric analysis of the leaves from visually asymptomatic trees and ones with clear symptoms let us to consider the tendency of dwarfism and more frequent cases of heterophilicity in the damaged plants (in the damaged plants in ‘Medovyiy’, a significant decrease in the linear parameters of both leaves and plants was noted; in ‘Smena’ – atypical round shape of leaf blades appeared). In the structural parameters under viral infection damage following significant differences were noted: a decrease in leaf thickness by 5-16%; a decrease in the palisade index to 0.50-0.61; large intercellular spaces appeared in the spongy tissue; chloroplast destruction started in the middle mesophyll layers and then it spread throughout the mesophyll, necrosis initiated in the spongy chlorenchyma; the number of lithocyst with cytolites and crystalline inclusions significantly increased, a decrease in the adaxial epidermis thickness was observed, the distribution density of stomatal apparatus changed. These structural features reduced the drought resistance of plants; degradation of chlorenchyma provoked the inhibition of production processes.
Brailko, V.A., Mitrofanova, I.V., Plugatar, Yu.V., Chelombit, S.V., Mitrofanova, O.V. and Chirkov, S.N. (2021). Morphological and anatomical changes in leaves of some Ficus carica L. cultivars damaged with viral diseases. Acta Hortic. 1310, 261-266
DOI: 10.17660/ActaHortic.2021.1310.40
common fig, anatomy, morphology, symptoms, viral infections

Acta Horticulturae