Rasit Asiloglu

• PhD
• Professor (Assistant) at Niigata University

The plant-microbe interactions, which is crucial for plant health and productivity, mainly occur in rhizosphere: a narrow zone of soil surrounding roots of living plants. The rhizosphere hosts one of the most intense habitats for microbial prey–predator interactions, especially between predatory protists and bacteria. Here, based on two key facts,...

Communities at any trophic level along the food chain are determined by simultaneous top-down (predators) and bottom-up (nutrients) effects; however, we still lack an understanding of this concept in the soil ecosystem. Here, we aimed to reveal the contributions of the top-down and bottom-up factors on the formation of paddy field bacterial communi...

Protists are among the most diverse and major microbial groups in the soil ecosystem and play versatile functional roles for soil fertility and agricultural productivity. However, protist community composition is poorly understood in paddy field soil, especially in alkaline paddy fields. Here we aimed to characterise protist communities of alkaline...

Biochar applications have an enormous impact on the soil microbial community and functionality. However, the majority of the knowledge on biochar–microbe interaction derives almost exclusively from bacterial and fungal studies, while the vast majority of eukaryotic diversity, protists, are mostly neglected. Protists play important roles in the soil...

Background Biological control (biocontrol) organisms are the key component of the sustainable agriculture. Although the majority of the research on biocontrol organisms focused on fungi and bacteria, recent studies revealed the importance of predatory protists in pathogen suppression through direct (by feeding on plant pathogens) and indirect (by e...

To overcome the global problem of food shortage while supporting sustainable life on Earth, we must appreciate the critical importance of soil microorganisms—the key drivers of essential ecosystem services such as nutrient cycling and plant productivity. Protists are one of the major microbial groups in soil ecosystem including primary producers, d...

Nitrogen fertilizers’ effects on protists in three paddy field soils were analyzed. Different nitrogen fertilizers had distinctive effects on the protist communities. The effect of nitrogen fertilizers on protist communities slightly depended on the soil types. Predatory protists were the main groups that were affected by nitrogen fertilizers. Prot...

Endophytic prokaryotes, bacteria, and archaea, are important microorganisms that benefit host plants by promoting plant growth and reducing stress. The objective of this study was to evaluate temporal shifts in the root endophytic prokaryotic communities associated with carrots (Daucus carota subsp. sativus) and the effect of organic matter applica...

This study aims to investigate the effects of soil as a microbial source on the assemblage of the endophytic bacterial communities in rice roots. Rice seedlings were grown hydroponically with the addition of a permeable bag filled with one of five soil types collected from different geographical locations in Japan. After 3 and 6 weeks, the endophyt...

Bacterial communities in the soil ecosystem including paddy fields are strongly controlled by the top-down force of predatory protists. However, the current knowledge on top-down regulation of bacterial communities exclusively comes from DNA-based molecular methods that have limitations to differentiate between alive and dead cells. Here, we compar...

Irrigated and rain-fed rice fields are unique agroecosystems and anthropogenic wetlands whose main feature is seasonal flooding. Flooded soils are characterized by spatiotemporal shifts and oscillation of the oxygen status and redox potential, sustaining varieties of microbial metabolisms, where bacteria and methanogenic archaea play principal role...

Microcosm experiments were performed to investigate the effect of organic material composition on soil bacterial and archaeal communities under paddy soil conditions. Rice straw and farmyard manure were used as the original organic materials, and three types of residues were prepared by sequential extraction from the original materials as follows:...

To highlight the importance of the soil-root interface in bacterial root colonization, we performed 16S rRNA gene amplicon sequencing on the Illumina MiSeq platform to characterize the bacterial endophytes of rice plants grown by two experiments – soil and hydroponic, considering their soil, solution, and endosphere compartments. We hypothesized th...

Maternal effects are ubiquitous in nature and have been demonstrated in a wide array of traits and taxa. In many species, the genotype of the mother is a major determinant of the phenotype of her offspring. In plants, less is known about the levels of sensitivity to stresses-mediated maternal effects. We generated 12 reciprocal crossed F2 lines fro...

The loss of cropland soils, climate change, and population growth are directly affecting the food supply. Given the higher incidence of salinity and extreme events, the cereal performance and yield are substantially hampered. Wheat is forecast to decline over the coming years due to the salinization widespread as one of the oldest and most environm...

Understanding the community composition and diversity of arbuscular mycorrhizal fungi (AMF) in agricultural ecosystems is important for exploring their potential for use in sustainable crop production. In this study, we collected rice root samples from upland rice fields under different agricultural practices in four districts of Bangladesh (Khagra...

The effects of protists on an indigenous soil bacterial community, putative bacterial genes involved in N-cycling, and the rice plant growth were studied in poultry litter biochar (PL) and rice husk biochar (RH) amended (with two application doses: 2% and 4% w/w) paddy field soil. The bacterial community composition, which was evaluated using 16S r...

Calcium cyanamide, a component of lime-N, is gradually hydrolyzed into urea in soil and generates dicyandiamide, a nitrification inhibitor. Calcium cyanamide also increases soil pH. In this study, we determined the effects of calcium cyanamide application and the consequent increase in soil pH on N2O emissions and soil bacterial community compositi...

Biochar-induced changes in microbial communities are exclusively derived from the studies on the soil bacterial and fungal communities, and we lack an understanding of how biochar can affect taxonomic and functional communities of protists. Here, the short-term effects of two biochars originating from rice husk and poultry litter (hereinafter refer...

Soils are characterized by diverse biotic and abiotic constituents, and this complexity hinders studies on the effects of individual soil components on microorganisms in soil. Although artificial soils have been used to overcome this issue, anoxic soils have not yet been examined. We herein aimed to create artificial soil that reproduces anaerobic...

Application of plant growth promoting rhizo-bacteria (PGPR) is a promising method for sustainably increasing the plant growth; however, survival of PGPR is the most important factor limiting its efficiency. We studied the effects of heterotrophic protists on the survival of introduced PGPR, Azospirillum sp. B510, on indigenous bacterial community s...

The rice rhizosphere is a hotspot for microorganisms, where heterotrophic protists are the major group of microeukaryotes and probably function as microbial predators. In this work, the microscale distribution of soil protists in a rice rhizosphere was studied in a microcosm experiment. Rice seedlings (Oryza sativa L. Nipponbare) were grown in “min...

The rhizosphere is one of the hot spots in soil ecosystems for a variety of microorganisms. In this study, we explored the seasonal change of the microeukaryotic community of a rice rhizosphere focusing on the active members through an RNA-based molecular approach. Rice plants (Oryza sativa L.) were grown in a pot where the rhizosphere was compartm...

Rice roots provide a specific habitat for microorganisms in the rhizosphere of a submerged field through supply of oxygen and organic matter. Many studies have focused on the microbial community in the rice rhizosphere, but less is still known about the microeukaryotic community structure of rice rhizosphere. This study explored the microeukaryotic...