Search

The extent to which pretransplant colonization of seedlings with the arbuscular mycorrhizal fungus (AMF) Schenck and Smith emend. Koske could enhance the post-transplant growth of two cultivars of (Lam.) de Wit (cv. K-8 and cv. K-636) in Al- and Mn-rich acid soils was evaluated in a greenhouse. Arbuscular mycorrhizal colonization measured at the end of the experiment was significantly stimulated by inoculation in both cultivars at all pH levels tested, although colonization was most stimulated if cv. K-8 was grown in the Al-rich soil at the lowest pH. Symbiotic effectiveness measured as P content of pinnules was significantly suppressed in both cultivars if they were grown at the lowest pH. Symbiotic effectiveness measured as pinnule P content and shoot biomass yield was enhanced in both cultivars by liming. The trends in effectiveness were similar in both cultivars, but cultivar effect was significant in the Mn-rich Oxisol (Wahaiawa soil) but not in the Al-rich Ultisol (Leilehua soil). The tolerance of the cultivars to acid soil toxicity in the Wahiawa soil varied with the pretransplant mycorrhizal status of their seedlings. The effect of pretransplant colonization of seedlings was to eliminate the differences in the tolerance of the cultivars to acid soil toxicity. Our data suggest that AMF could offset some of the growth reduction associated with soil acidity and that host genotype could play a role in this regard. [ABSTRACT FROM AUTHOR]