Effect of Mycorrhiza Inoculation on Phosphate Fertilization Efficiency of Soils Cultivated with Tissue Cultured Date Palm Trees

Abstract

The aim of this current study was to evaluate the growth and absorption of phosphorus (P) by tissue cultured date-palm offshot trees (cv. Khallas) grown in pots filled with cultivated soils inoculated with mycorrhiza (Mycorrhiza Glomus) and supplied with P from triple super-phosphate (TSP) or rock phosphate (RP) with control treatments (uninoculated and unfertilized). The obtained results showed that the roots of the tissue cultures trees were invaded after being inoculated with the mycorrhiza strains of LPA21 and LPA22. Also, the mycorrhiza inoculation caused significant increases in growth traits of the inoculated tissure cultured date-palm trees represented by the length as well as the fresh and dry weights of both the stems and roots as compared to the uninocluated trees. Also, it was found that application of phosphate fertilizers caused significant increases in growth characters of these trees in comparison with the control treatment (unfertilized). The values of the length of stems and roots as well the fresh and dry weights of stem and roots were significantly higher with the application of TSP than with the RP. The obatined results also showed that there were positive interaction effects between inoculation with both strains and appliaction of phosphate fertilizers on growth and phosphorus contents in the stems and roots of the tissue cultured date palm trees. The inocultaed trees absorbed more isotops phosphorus from the soils than the uninoculated trees. It can be recommended to take into considrations the appropriate selection of the mycorrhiza strain when used for inoculation in oredr to assure its utilization success for the tissue cultured date palm trees. Also, it is favorable to use of the more readily available phosphate fertilizers with the mycorrhiza inoculation particularly for cultivated soils characterized by its high P fixation capacity resulting from their high calcium carbonate contents as those in the Al-Hassa Oasis and KSA in general. Nonetheless, the use of RP is potentially feasible.