The content of photosynthetic pigments in the leaves of Chrysanthemum×hortorum Bailey

Abstract

The article presents data on the content of the main photosynthetic pigments in the leaves of various varieties of Chrysanthemum×hortorum, depending on the methods of cultivation. The efficiency of the photosynthetic apparatus is one of the most important parameter of the adaptive potential of plants in limiting environmental conditions. It’s linked with the peculiarities of the development and functioning of the pigment complex. The purpose of the work is to study the features of the content of photosynthetic pigments in the leaves of various Chrysanthemum×morifolium varieties to expand the assortment in the humid subtropics of Russia. The studies were conducted on model varieties of large-flowered (‘Sevan’ control, ‘Gilbert Leigh Purple’, ‘Gagarin’) and small-color chrysanthemums (‘Golden Niva’ control, ‘Tigerrag’, ‘Vesuvio’, ‘Dante’) cultivated in open and closed ground. It was found that relative humidity and illumination are higher in open ground throughout the year (average annual values in open ground are 65.4 % and 28 563 lx, in closed ground 61.8 % and 18 763 lx), while the temperature regime is higher in closed ground (average values in open and closed ground +18.6 °C and +20.8 °C, respectively). This favorably affects the preservation of the roots of chrysanthemum in winter when grown indoors in an unregulated microclimate (average temperature in the winter months in the open ground is +9.1 °C, in the closed +11.0 °C), but it negatively affects vegetative plants in the summer period (average temperature indicators in open and closed ground are +26.8 °С and +28.8 °С, respectively). The content of photosynthetic pigments in the leaves of Chrysanthemum×hortorum was studied in the period of the budding and flowering vegetation 2018-2019. Varietal differences were noted in the quantitative composition of pigments and their ratio, as well as differences depending on growing conditions in open ground and in protected ground (in glass greenhouses under solar heating).