SEASONAL VARIATIONS IN LEAF NUTRIENT CONCENTRATIONS IN THREE FIG (FICUS CARICA L.) VARIETIES

Leaves from three fig (Ficus carica L.) varieties (White, Black Royal and White Royal) were collected at different development stages of the tree, i.e. flowering, fruit development, fruit maturity, and postharvest, after which the variation of macro- (K, Na, Ca, Mg, N, P) and micronutrient (Fe, Mn, Cu, Zn, B) concentrations during the growing season were measured. The leaf concentrations of N, P, K, Ca and Mg during the studied period for the White variety ranged from 19 to 25, from 1.1 to 1.3, from 13 to 18, from 20 to 24 and from 2.7 to 2.9 g kg(-1) (on dry weight basis DW), respectively. The corresponding values for the Black Royal variety ranged from 22 to 26, from 1.1 to 1.4, from 13 to 19, from 23 to 29 and from 2.5 to 3.4 g kg(-1) (DW), respectively. The corresponding values for the White Royal variety ranged from 19 to 25, 0.9 to 1.2, 10 to 17, 26 to 30 and 4.3 to 4.5 g kg(-1) (DW), respectively. The leaf content values of Fe, Zn, Cu, Mn, and B during the studied period for the White variety ranged from 107 to 147, from 42 to 35, from 10 to 9, from 52 to 61 and from 23 to 40 mg kg(-1) (DW), respectively. The corresponding values for the Black Royal variety ranged from 77 to 155, from 38 to 41, from 8 to 9, from 52 to 66 and from 23 to 56 mg kg(-1) (DW), respectively. The corresponding values for the White Royal variety ranged from 84 to 126, from 44 to 48, from 8 to 9, from 88 to 98 and from 23 to 47 mg kg(-1) (DW), respectively. According to the results, the leaf nutritional content varies in the plant's development stages and there were differences between the fig varieties in the nutrient content at different development stages, which indicated that different varieties of plants need different amounts of nutrients during the growing cycle. These results should be taken into consideration when elaborating a fertilization program.