RESPONSE OF FLAME SEEDLESS GRAPEVINE CUTTINGS GROWN UNDER HYDROPONIC CULTURE CONDITIONS TO SOME BIOFERTILIZATION TREATMENTS

Abstract

A hydroponic culture experiment was carried out during two successive seasons (2017 and 2018) on two years old grapevines cv. Flame seedless (Vitis vinifera L.) aimed to study the effect of Mycorrhiza, Azospirillum and Azotobacter treatments on growth, leaf chemical composition and cation equilibrium of Flame Seedless grapevines own rooted cuttings. The plants were two years old at the start of the experiment. The experiment was conducted under controlled conditions in Laboratory, with temperature fixed at 25 ± 3C°, relative humidity between 75–85% and 14-hours light exposure. Three microorganisms commonly used in biofertilization, namely: Arbuscular Mycorrhiza, Azospirillum brasilense, and Azotobacter chrococcum were used as biofertilizers. Standard nutrient solution, adapted with grapevines needs, reported by Morard 1995 and Ibrahim (2001) was prepared and used in this experiment. The Flame seedless own rooted cuttings exhibited high growth parameters as a result to biofertilization than those untreated cuttings. However, the higher values of shoot length, number of leaves/shoots, leaf area, chlorophyll contents and growth ratio at nutrient solutions was obtained from the seedlings treated with the three micro-organisms in combination. The chemical analysis of mature leaves and roots indicated that the own rooted cuttings received Mycrrohiza showed significantly higher ratio of P, K, Mg and Fe than other bio-fertilizers treatments. On the other hand, the Azotobacter treatments exhibited higher levels of N and Zn contents. Significant differences were observed between the two cultivars in Ca contents. However, the lowest N. P, K, Mg, Fe and Zn values were obtained from control treatment.