EFFECT OF HUMIC ACID, BIO-FERTILIZERS AND MICRO-ELEMENTS ON LEAF MINERAL CONTENTS OF KING RUBY GRAPEVINES

Abstract

The present investigation was carried out during the seasons of 2011 and 2012 to study the effect of soil application of humic acid (at 0.75, 1.5 and 3 g / vine) with or without bio-fertilizers (Serratia sp. + Bacillus polymyxa + Pseudomonas fluorescens + Trichoderma viride + Trichoderma harzianum) at 7.14 ml / vine and micro-elements (FeSO4.7H2O at 0.35 g + ZnSO4.7H2O at 0.18 g + MnSO4.H2O at 0.18 g) / vine on mineral contents of King Ruby leaf petioles. Results obtained showed that adding humic acid at 3 gvine with bio-fertilizers at 7.14 mlvine and micro-elements (FeSO4.7H2O at 0.35 g + ZnSO4.7H2O at 0.18 g + MnSO4.H2O at 0.18 g) / vine, activated the absorption of macro-elements since it produced significantly the highest values of N, P and K content in leaf petioles when compared with all of the other treatments, N values were 3.83 and 3.71 %, P values were 0.47 and 0.42 % and K values were 2.49 and 2.59 % in 2011 and 2012 seasons, respectively. Concerning micro-elements, it was observed that adding humic acid at 3 gvine with bio-fertilizers and micro-elements also activated micro-elements uptake by grapevines, it recorded in 2011 and 2012, respectively the highest values, Fe was (131.00 and 128.43 ppm), Zn (45.40 and 47.70 ppm) and Mn was (150.07 and 143.37 ppm). On the other hand, the control treatment gave the lowest values of macro and micro-elements if compared to those resulted in the other treatments in both seasons of the study.