Fungal Pathogens in Grasslands

Abstract

Grasslands are major primary producers and function as major components of important watersheds. Although a concise definition of grasslands cannot be given using a physiognomic or structural approach, grasslands can be described as vegetation communities experiencing periodical droughts and with canopies dominated by grasses and grass-like plants. Grasslands have a cosmopolitan distribution except for the Antarctic region. Fungal interactions with grasses can be pathogenic or symbiotic. Herbivorous mammals, insects, other grassland animals, and fungal pathogens are known to play important roles in maintaining the biomass and biodiversity of grasslands. Although most pathogenicity studies on the members of Poaceae have been focused on economically important crops, the plant-fungal pathogenic interactions involved can extend to the full range of ecological circumstances that exist in nature. Hence, it is important to delineate the fungal pathogen communities and their interactions in man-made monoculture systems and highly diverse natural ecosystems. A better understanding of the key fungal players can be achieved by combining modern techniques such as next-generation sequencing (NGS) together with studies involving classic phytopathology, taxonomy, and phylogeny. It is of utmost importance to develop experimental designs that account for the ecological complexity of the relationships between grasses and fungi, both above and below ground. In grasslands, loss in species diversity increases interactions such as herbivory, mutualism, predation or infectious disease transmission. Host species density and the presence of heterospecific host species, also affect the disease dynamics in grasslands. Many studies have shown that lower species diversity increases the severity as well as the transmission rate of fungal diseases. Moreover, communities that were once highly diverse but have experienced decreased species richness and dominancy have also shown higher pathogenicity load due to the relaxed competition, although this effect is lower in natural communities. This review addresses the taxonomy, phylogeny, and ecology of grassland fungal pathogens and their interactions in grassland ecosystems.

Soil Mycobiome Diversity under Different Tillage Practices in the South of West Siberia

“…Our study showed that no tillage shifted soil mycobiome composition (species richness) closer to the one in the undisturbed soil under natural vegetation, most likely by altering physicochemical properties of the soil environment [ 63 ], thus expanding the opportunity space [ 57 ] for fungi surviving and thriving. As, by general consensus, species-richer fungal communities or naturally developed communities are regarded as “healthier” [ 64 ] in comparison with agriculturally used ones, our results support the notion that switching the long-term conventional tillage fields to the no-till ones can improve soil health [ 65 ] and ecosystem productivity.…”

Hyphal Fusions Enable Efficient Nutrient Distribution in Colletotrichum graminicola Conidiation and Symptom Development on Maize

“…As the members of this genus are able to infect virtually any plant and can cause substantial losses of fruit, vegetables and cereals, this group ranks in the top 10 of important plant pathogenic fungi [3]. C. graminicola belongs to the graminicola-caudatum complex, which specializes in the infection of a wide variety of grasses including important crops such as maize and sorghum [1,4,5]. This fungus causes corn anthracnose disease in several Zea mays tissues such as leaves (anthracnose leaf blight, ALB), stems (anthracnose stalk rot, ASR) and roots, and can cause systemic plant infections [6,7].…”

Comparative transcriptomic analysis of the gene expression and underlying molecular mechanism of submergence stress response in orchardgrass roots

“…The grassland covers an area of 52,544,000 km 2 , which is 40.5% of the world’s land area. It is the second largest land type for human habitation after agricultural land ( Karunarathna et al., 2021 ). Orchardgrass is a cold-season, and perennial forage grass native to Eurasia and North Africa.…”