Arbuscular mycorrhizal fungus on the initial growth and nutrition of Coffea arabica L. genotypes

ABSTRACT The benefits of mycorrhization occur with the growth of hyphae in colonized roots by promoting an increase of the contact surface which improves the initial growth due to a better absorption of water and nutrients. The objective was to evaluate the effect of arbuscular mycorrhizal fungus Rhizophagus clarus inoculation over the initial development and nutritional response of six genotypes of Coffea arabica L. Six genotypes of Coffea arabica L. were used (MGS Aranas, H29-1-8-5, Red Catuai IAC 144, IPR 100, Catigua MG2, Paraiso H 419-1) and with arbuscular mycorrhizal fungus - AMF: Rhizophagus clarus and without the application of the fungus. For the production of coffee seedlings, seeds were placed to germinate in plastic trays with sterile sand. After germination, 10 seedlings of each genotype were transferred to 0.120 dm3 polyethylene tubes with substrate. Then the inoculation of five seedlings of each genotype with the AMF R. Clarus was performed. When the seedlings with and without inoculation with the AMF presented six pairs of leaves they were transplanted to 13-liter pots containing soil (Dystrophic red-yellow latosol). The inoculation favored the initial growth of the coffee plants and its intensity varied according to the genotypes. The genotypes H 29-1-8-5, Red Catuai IAC 144 and Catigua MG 2 were the ones that presented higher shoot dry mass, root dry mass, total dry mass and accumulation of P, in relation to MGS aranas, Paraiso H 419-1 and IPR 100, so they are the most promising to be inoculated with the arbuscular mycorrhizal fungus.