Growth response, phosphorus content and root colonization of Polylepis australis Bitt. seedlings inoculated with different soil types
- 375 Downloads
Polylepis forests are one of the most endangered high mountain ecosystems of South America and reforestation with native Polylepis species has been highly recommended. Greenhouse bioassays were set up to determine the influence of three different soils on growth and phosphorous nutrition of Polylepis australis seedlings. Soils were collected from a grassland, a rare mature forest and a forest degraded due to repeated fires. We identified the arbuscular mycorrhizal fungi (AMF) present in the three soils and after 12 months we harvested the seedlings to evaluate root and shoot biomass, plant P content and root colonization by native AMF and dark septate endophytes (DSE). The soil inocula contained 26 AMF morphospecies. Grassland inoculum showed the highest AMF richness, and mature forest showed a different AMF community assembly from grassland and degraded forest inocula. Root biomass and root colonization were highest in seedlings inoculated with mature forest soil, meanwhile shoot biomass and plant P content were similar between all treatments. AMF colonization correlated negatively with DSE and root biomass was negatively correlated with DSE colonization, thus these fungal symbionts could be competing for resources. Our results indicate that AMF inoculum from the mature forest stand has the potential to improve P. australis performance, probably due to the dominance of Glomeraceae and Acaulosporaceae families. However, other soil microorganisms could be together with AMF in the natural inocula, affecting the growth response of P. australis seedlings. Future studies evaluating the effect of these inocula under field conditions should be carried out.
KeywordsArbuscular mycorrhizal fungi Dark septate endophytes Mountain forest Natural soil inocula
Arbuscular mycorrhizal fungi
Dark septate endophytes
This work was financially supported by Agencia de Promoción Científica y Tecnológica—PICT 438-2008, Consejo Nacional de Investigaciones Científicas y Técnicas—PIP 0269 and Secretaría de Ciencia y Técnica de la Universidad Nacional de Córdoba (SECyT-UNC) Res Nº 162/12. We are very grateful to M. N. Cabello and G. Grilli for the constructive suggestions made on our manuscript. F.S. is grateful to CONICET for providing her fellowship. A.B. and D.R. are researchers of CONICET.
- Cabido M (1985) Las comunidades vegetales de Pampa de Achala, Sierras de Córdoba, Argentina. Doc Phytosociol 9:431–443Google Scholar
- Fjeldså J, Kessler M (1996) Conserving the biological diversity of Polylepis woodlands of the highland of Peru and Bolivia. A contribution to sustainable natural resource management in the Andes, Nordeco, p 250Google Scholar
- Jones JB, Wolf B, Mills HA (1991) Plant analysis handbook. A practical sampling, preparation, analysis, and interpretation guide. Micro-Macro Publishing, Inc, Athens, p 213Google Scholar
- Martino J, Urcelay C, Renison D (2011) Crecimiento y colonización micorrícica de Polylepis australis Bitter (Rosaceae) en suelos con distinta historia de pastoreo. Kurtziana 36:69–77Google Scholar
- Neumann E, Eckhard G (2010) Nutrient uptake: the arbuscular mycorrhiza fungal symbiosis as a plant nutrient acquisition strategy. In: Koltai H, Kapulnik Y (eds) Arbuscular mycorrhizas: physiology and function. Springer Netherlands, pp 137–167Google Scholar
- Renison D, Cingolani AM, Suarez R, Menoyo E, Coutsiers C, Sobral A, Hensen I (2005) The restoration of degraded mountain woodlands: effects of seed provenance and microsite characteristics on Polylepis australis seedling survival and growth in Central Argentina. Restor Ecol 13:129–137CrossRefGoogle Scholar
- Schenk NC, Perez Y (1990) Manual of identification of vesicular-arbuscular mycorrhizal fungi. Gainesville, USA, p 286Google Scholar
- Smith SE, Read D (2008) Mycorrhizal symbiosis. Academic Press, Great BritainGoogle Scholar
- Smith SE, Jakobsen I, Grønlund M, Smith FA (2011) Roles of arbuscular mycorrhizas in plant phosphorus nutrition: interactions between pathways of phosphorus uptake in arbuscular mycorrhizal roots have important implications for understanding and manipulating plant phosphorus acquisition. Plant Physiol 156:1050–1057PubMedCrossRefGoogle Scholar