The effects of high concentration of bicarbonate applications on kiwifruit genotypes with different ploidy levels on some growth parameters of leaves

Abstract

: The high concentration of bicarbonate ion ( HCO₃ - ) in irrigation water or soil is a limiting factor for the growth and production of kiwifruit vineyards. Especially the high concentration of bicarbonate in irrigation water can cause negative effects on the development of many plants at different rates. In this study, the effects of different concentrations (0, 170, 350, and 550 mg L-1) of bicarbonate ion (HCO₃ - ) in irrigation water on six kiwifruit seedlings (DA 1 , DA 2 , CK 1 , CK 2 , CK 3 , AA) were studied in the greenhouse condition. The six kiwifruit seedlings used in the study belong to a total of 3 different species ( A. deliciosa, A. chinensis , and A. arguta ) and also have different ploidy levels (2n, 4n, and 6n). The highest (16.6%) leaf abscission was found in AA ( A. arguta ) seedlings when exposed to HCO₃-stress, and the lowest value (1.19%) was found in DA 1 ( A. deliciosa cv. ‘Bruno’) seedlings. Depending on the cultivar or species, bicarbonate caused leaf chlorosis at different rates in kiwifruit seedlings. CK 1 ( A. chinensis ) seedlings showed the highest (38.46%) leaf chlorosis and DA 2 ( A. deliciosa ) seedlings showed the lowest (6.95%) leaf chlorosis. Bicarbonate reduced chlorophylls and carotenoid content in all kiwifruit genotypes. Furthermore, it induced leaf iron (Fe), manganese (Mn), and zinc (Zn) deficiency. Seedlings of ‘Bruno’ showed the lowest decline of leaf iron (Fe) and Zinc (Zn) content when exposed to HCO₃-stress. In contrast, a high level of Manganese (Mn) was found in seedlings of CK3. Overall, it was detected a close relationship between bicarbonate stress and nutrient homeostasis in different kiwifruit genotypes.