Native Mycorrhizae for Improving Seedling Growth in Avocado Nursery (Persea americana Mill.)

Objectives: This research aims to evaluate the efficiency of the use of native mycorrhizae on seedling growth of avocado to produce high quality avocado plants. Methods: Root and soil sampling was done in 14 avocado production sites from Interandean valleys of Ecuador. Native mycorrhizae inoculum and two control treatments (commercial product and absolute control without inoculation) were evaluated in both seed and seedlings. A randomized complete block design was applied for the trails. Analysis of variance was run to determine statistical differences and the Tukey test at 5% was used to determine ranges of significance. Findings: Soils showing largest number of spores and highest percentage of mycorrhizal colonization were collected in Tumbabiro (Imbabura) and San José de Minas (Pichincha). Compared to the absolute control, an increase in total phosphorus and dry matter content of 84% and 100%, respectively, was observed in trap plants. Using inoculum from Tumbabiro and San José de Minas to inoculate avocado seeds and seedlings, dry matter content increased by 44% while the percentage of total phosphorus increased by 42% compared to the controls. Although acceptable results were obtained with the commercial product about the percentage of phosphorus and dry matter, poor percentages of ischolar_main colonization were obtained; whereas the native inoculum from Tumbabiro and San José de Minas produced better results improving avocado seedling growth in nursery. Application/Improvements: This research allows us to infer that native mycorrhizal strains are effective as inoculum to enhance the development of avocado seedlings.