Title:	Colonization of Acacia species by VA mycorrhizal fungi in a Mediterranean environment.
Authors:	GAIAD, S.
Affiliation:	SERGIO GAIAD, CNPF.
Date Issued:	1989
Citation:	1989.
Pages:	110 f.
Description:	This study investigated the factors affecting vesicular–arbuscular (VA) mycorrhizal associations in Acacia pulchella, an important leguminous understorey species in jarrah (Eucalyptus marginata) forests of south-western Australia. The species plays a key role in nutrient cycling and is widely used in revegetation after bauxite mining. Because VA mycorrhizal fungi enhance nutrient uptake and are obligate symbionts, their activity is closely linked to plant growth and seasonal environmental conditions. Three experiments were conducted to assess seasonal variation, soil depth effects, phosphate addition, and soil disturbance on mycorrhizal infectivity. Results showed that in natural jarrah forests, mycorrhizal formation was strongly influenced by rainfall, decreasing during the dry summer and increasing with winter rains. In contrast, soils from restored mining areas showed consistently low colonization and no clear seasonal pattern, likely due to soil disturbance reducing fungal propagules. Soil disturbance significantly affected infectivity assessments, with drying and mixing reducing winter infection levels. Mycorrhizal colonization was concentrated in the top 10 cm of soil, corresponding to the main root distribution of A. pulchella. Phosphate addition did not significantly affect colonization in the upper soil layers. The genus Glomus was the dominant VA mycorrhizal fungus across most conditions, while Gigaspora was more prominent during early seedling growth. Overall, the study highlights the strong influence of seasonal moisture, soil disturbance, and soil depth on VA mycorrhizal infectivity. It emphasizes the importance of minimizing soil disturbance in experimental assessments and suggests that combining glasshouse and field studies improves the reliability of infectivity measurements under Mediterranean climatic conditions.
Thesagro:	Colonização Fungo Micorriza
NAL Thesaurus:	Acacia pulchella Gigaspora Glomus
Notes:	Thesis (Master of Science) - University of Western Australia, Perth.
Type of Material:	Teses
Access:	openAccess
Appears in Collections:	Tese/dissertação (CNPF)