The combined effects of gibberellic acid and kinetin on growth, yield and quality in globe artichoke (Cynara scolymus L.)

Abstract

: The globe artichoke cv. 'Balady' is considered one of the most important cultivars in Egypt due to the earliness of its flowering compared with other cultivars, but the size of its head is small. Two field experiments were conducted during 2019-2020 and 2020-2021 growing seasons to assess the effects of gibberellic acid (GA 3 ) and kinetin (KN) alone or in various combinations on the growth, earliness, productivity, and head quality of globe artichokes. The results showed that plants treated with combination of GA 3 (20 ppm) and KN (50 ppm) had superior effects on growth, number of early heads feddan -1 , total number of heads feddan -1 , fresh weight of head, and head size as measured by length, and diameter of the head. Comparison with the control, the foliar spraying of 20 ppm GA 3 + 50 ppm KN raised the percentages of number of early head feddan -1 by 180 %, total number of head feddan -1 by 24 %, head fresh weight by 8%, head length by 21% and head diameter by 21%, in both seasons. Also, the same treatment recorded the highest values for the leaf minerals and chlorophyll contents as well as head quality traits (minerals, protein, inulin and ascorbic acid content). However, only the content of total phenolic compounds in heads was reduced with all exogenous hormone applications. Therefore, the combined treatment with 20 ppm GA 3 and 50 ppm KN might be considered as an optimal treatment to produce the highest yield with good quality of globe artichoke cv. 'Balady'