Abstract

Soils in northern Chile are poor in organic matter (OM), which defines a reduced spectrum of cultivable filamentous fun- gi. In its traditional practice, olive growers apply OM to im- prove soil conditions, stimulating the development and expres- sion of the soil biome. In this work the structure and dynamics of cultivable fungal communities present in the soil of olive or- chards in the Azapa valley were determined. Using criteria of abundance and diversity of cultivable filamentous fungi, two ol- ive groves were compared, demonstrating the short-term effect of the application of mature compost. The analysis of the fun- gal population evaluated the colony forming units (CFU) after five days of incubation in PDA plus chloramphenicol at 25 ±1°C. Each fungal colony was recorded, grouping those with the same growth rate and characteristics. From monosporic cultures, iso- lated taxa were identified morphologically. Rarefaction curves were generated, and the different soils were grouped before and after the application of OM. The composition of the communi- ties in both soils was compared using Venn diagrams. With the Shannon-Wiener diversity index, the effect of compost applica- tion on diversity was calculated. The application of compost did not generate significant changes in the abundance and diversity, but modified the composition favoring the abundance of decom- posing fungi and biocontrollers, which is a result of the increase of OM, improving the health and biological activity of the soil.