ABSTRACT
The assembly of fungal communities on stone materials is mainly influenced by the differential bioreceptivity of such materials and environmental conditions. However, little is known about the role of fungal interactions in the colonization and establishment of fungal species. We analyzed the effects of intra- and interspecific interactions between 11 species of fungi in oligotrophic and copiotrophic media and on limestone coupons. In a previous study, these species were the most frequently isolated in the epilithic biofilms of limestone walls exposed to a subtropical climate. In the culture media, we found a greater frequency of intra- and interspecific inhibitory effects in the oligotrophic medium than in the copiotrophic medium. On the limestone coupons, all fungi were able to establish; however, the colonization success rate varied significantly. Cladosporium cladosporioides had a less extensive colonization in isolation (control) than in dual interactions (coexistence) with other species. Phoma eupyrena exhibited the highest colonization success rate and competitive dominance among all tested species. X-ray diffraction (XRD) and scanning electron microscope (SEM) analyses revealed that Pestalotiopsis maculans and Paraconiothyrium sp. produced calcium oxalate crystals during their growth on coupon surfaces, both in isolation and in dual interactions. Our results demonstrate that interactions between abundant fungal species influence the fungal colonization on substrates, the biomineralization and the fungal community assemblage growing in limestone biofilms.
Subject(s)
Calcium Carbonate , Fungi/isolation & purification , Culture Media , Fungi/classification , Microscopy, Electron, Scanning , Species Specificity , X-Ray DiffractionABSTRACT
El follaje de arbustivas y arbóreas tropicales representan una fuente importante de nutrimentos para el ganado bovino en pastoreo de gramíneas tropicales. La composición química, digestibilidad y consumo del follaje de arbustivas y arbóreas son generalmente satisfactorios para su aprovechamiento por los rumiantes, aportando proteína en el rumen que favorece una rápida disponibilidad de nitrógeno para el crecimiento microbiano. Sin embargo, la disponibilidad de energía en relación a la del nitrógeno en el rumen, parece ser una restricción para el uso eficiente del follaje. La incorporación del follaje de arbustivas y árboles forrajeros en la ración de rumiantes tiene el potencial para aumentar la producción animal en sistemas de doble propósito en los trópicos, ya que son una fuente importante de nutrimentos para el ganado que consume gramíneas bajo pastoreo.
Foliage of tropical trees and shrubs represents an important source of nutrients for cattle grazing tropical grasses. Chemical composition, digestibility and intake of foliage of shrubs and trees are generally satisfactory for their utilization by ruminants, supplying protein to the rumen that promotes a readily available nitrogen for microbial growth. However, energy availability relative to nitrogen in the rumen, seems to be a constraint to the efficient use of foliage Incorporation of foliage of trees and shrubs in ruminant rations has the potential to increase animal production in dual-purpose systems in the tropics, since they are an important source of nutriments for livestock under grazing conditions.