In vitro EVALUATION OF EUCALYPTUS ECTOMYCORRHIZAE ON SUBSTRATE WITH PHOSPHORUS DOSES FOR FUNGAL PRE-SELECTION

Lidiomar Soares Costa,Paulo Henrique Grazziotti,Márcio José Rossi,Ângela Laís Fernandes Gomes,Victor Hugo Duarte Da Costa,Alexandre Christófaro Silva,Enilson De Barros Silva,Danielle Cristina Fonseca Santos Grazziotti

doi:10.1590/0100-67622015000100012

Abstract

The benefit promoted by ectomycorrhizal depends on the interaction between symbionts and phosphorus (P) contents. Phosphorus effect on ectomycorrhizal formation and the effectiveness of these in promoting plant growth for fungal pre-selection were assessed under in vitro conditions. For P effect evaluation, Eucalyptus urophylla seedlings inoculated with four Pisolithus sp. isolates and others non-inoculated were grown on substrate containing 0.87, 1.16 and 1.72 mg P per plant. For evaluation of effectiveness and fungal pre-selection, other 30 isolates of Pisolithus sp., Pisolithus microcarpus ITA06 isolate, Amanita muscaria AM16 isolate, Scleroderma areolatum SC129 isolate were studied. D26 isolate promoted the highest plant heights for the three P doses, D51 at the lower dose and D72 at the intermediate dose. P doses did not influenced shoot fresh weight and fungal colonization. In the pre-selection of fungi, 14 isolates of Pisolithus sp., P. microcarpus ITA06 isolate and S. areolatum SC129isolate increased plant height and fresh weight. D82 isolate of Pisolithus sp. had effect singly on plant height while D17 and D58 on fresh weight. Of these, only D15, D17, D58 and ITA06 had typical ectomycorrhizae. The cultivation in vitro has shown adequate for pre-selection of ectomycorrhizal fungi. Colonization and benefits depend on species and isolate. D15, D17 and D58 of Pisolithus sp. and P. microcarpus isolate ITA06 are the most promising for nursery studies.

Highlights

Ectomycorrhizal fungal (EMF) can act with variable efficiency on plant growth, especially those belonging to Eucalyptus genus (SAWYER et al, 2003)
Height growth ceased after 30 days of inoculation, what was more pronounced at the highest P dose
Plants inoculated with D3, D26, and D72 isolates at the lowest P dose and for non-inoculated at the intermediate dose (1.16 g plant-1 P), the plant height increased linearly up to the 40th day

Summary

Introduction

Ectomycorrhizal fungal (EMF) can act with variable efficiency on plant growth, especially those belonging to Eucalyptus genus (SAWYER et al, 2003). The main effect is the increase of root absorption surface, allowing better use of water and nutrients such as N, K and especially P, which is less mobile in soil (BOUGHER et al, 1990; SAWYER et al, 2003). Overall, these benefits obtained under ectomycorrhizal association are variable and dependent on soluble P availability in soil, which in large amounts can limit association and its scarcity affects plant growth and yield. For Eucalyptus dunnii seedlings inoculated with four EMF and grown in fertilized substrates with 0 to 8 mg P per plant, the doses above 4 mg per plant completely inhibited EMF colonization for three isolates (SOUZA et al, 2004)

Methods

Results

Discussion

Conclusion