CHLOROPHYLL AND CAROTENOID CONTENT IN WOLFBERRY (LYCIUM BARBARUM L.) LEAVES

Abstract

The aim of the study included the spectrophotometric quantification of chlorophyll and carotenoid pigments and the estimation of the ratios of the respective pigments in the species Lycium barbarum L. from the spontaneous flora and in four cultivars of this species ('Licurici', 'New big', 'Amber Sweet' and 'Ning Xia N1'), obtained by tissue culture in the Laboratory of Embryology and Biotechnology of the "Alexandru Ciubotaru" National Botanical Garden (Institute). The total content of chlorophyll pigments was between 6.934 and 11.604 mg/g plant mass. The minimum values, similarly to the separate fractions of chlorophyll a and b, were recorded in the leaves collected from wolfberry plants in the spontaneous flora. The maximum total chlorophyll content is characteristic of the 'Ning Xia N1' cultivar, which also demonstrated the highest chlorophyll a content, quantified separately. This is also true for the content of carotenoids. The ratio of chlorophyll a to b is about 3:1 in the leaves collected from the cultivated varieties and exceeds 4:1 in the plants found in the spontaneous flora. However, the ratio of total chlorophyll to carotenoids in the leaves of specimens from the spontaneous flora indicated a value equal to the average of this ratio calculated for the four cultivated varieties. The cluster analysis confirmed the differences of the contents of chlorophyll a, chlorophyll b and carotenoids between the cultivated goji varieties and the species Lycium barbarum L. from the spontaneous flora, and the similarities between the goji plants from the spontaneous flora and the cultivated varieties, particularly 'Licurici' and 'Ning Xia N1', in terms of the ratio of the total chlorophyll content to the carotenoids. The generalization of the results obtained in the study on chlorophyll and carotenoid pigments and the estimation of the values established between their ratios allow us to assume that all four cultivars of Lycium barbarum L. ('Licurici', 'New big', 'Amber Sweet' and 'Ning Xia N1') have acclimatized very well to the pedoclimatic conditions of the Republic of Moldova, and the determined optimal values indicate a good development of the vital processes of the plants.