An experiment was conducted at the Embrapa -- Cassava and Tropical Fruit Crops with the aim of estimating the genotypic determination coefficient (b) of papaya for its capacity of associate and response to arbuscular mycorrhizal fungi (AMF). Four genotypes and one variety of both "Solo"and "Formosa" groups were tested, inoculated or not with Gigaspora margarita in a soil which received 30 mg dm-3 of phosphorus. Data of shoot dry weight (SDW), mycorrhizal efficiency and colonization were statistically analized to generate the coefficient. All genotypes responded significantly to AMF but plants from "Formosa" group showed lower root length; mycorrhiza efficiency and colonization were similar for both groups, but there was no correlation between these characteristics; inoculation increased P, K and Cu absorption with higher values for the variety of each group. Coefficient "b" showed that for "Formosa" group, plant breeding may modulate shoot plant production, root length, plant heigth and mycorrhizal effeciency; for "Solo"group this effect showed to be more probable for root colonization than to mycorrhizal efficiency.
Mycorrhizal efficiency; Gigaspora margarita; root length; Carica papaya
