Long-term effect of non-irrigation and irrigation on soil Pythium , Fusarium , and Rhizoctonia communities and their rel
- PDF / 1,171,665 Bytes
- 18 Pages / 547.087 x 737.008 pts Page_size
- 42 Downloads / 179 Views
Long-term effect of non-irrigation and irrigation on soil Pythium, Fusarium, and Rhizoctonia communities and their relation with seed-rot, root-rot, and damping-off of soybean Bo Liu & Hsinho Wei & Weishou Shen & Hosanna Smith
Accepted: 23 June 2020 # Koninklijke Nederlandse Planteziektenkundige Vereniging 2020
Abstract Long-term non-irrigation (N-IRR) and irrigation (IRR) might affect pathogen communities causing seed-rot, root-rot, and damping-off of soybean. Characterization and quantification of Pythium, Fusarium, and Rhizoctonia spp. are critical for understanding the ecology of these microorganisms and management of root diseases. The populations and communities of Pythium, Fusarium, and Rhizoctonia were assessed in soils with long-term NIRR and IRR using soil dilution plating, denaturing gradient gel electrophoresis (DGGE), and DNA sequence analysis. Disease incidences of seed-rot, root-rot, and dampingoff of soybean were also evaluated with the soils from NIRR and IRR in a growth chamber. Results showed that the population densities of Pythium and Rhizoctonia based on dilution plating and richness based on DGGE were significantly lower in soils with N-IRR than IRR, whereas the population densities of Fusarium and richness of Fusarium were significantly higher in soils with N-IRR than IRR. Cluster analysis based on DGGE band patterns demonstrated that the communities of Pythium, Fusarium, and Rhizoctonia were separated based on N-IRR and IRR. Species diversities of some Pythium, Fusarium, or Rhizoctonia were impacted differently in soils with N-IRR and
B. Liu (*) Department of Plant Pathology, University of Arkansas, Fayetteville, AR 72701, USA e-mail: [email protected] H. Wei : W. Shen : H. Smith Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE 69101, USA
IRR. Moreover, canonical correspondence analysis (CCA) showed that the disease incidences were positively correlated with levels of soil moisture, pH, the populations of Pythium and Rhizoctonia, richness of Pythium and Rhizoctonia, and negatively correlated with soil porosity, humic matter, and potassium. Long-term N-IRR and IRR could impact pathogen populations and communities and disease incidences differently, and the disease complex might be caused by different species under different systems. Keywords Non-irrigation and irrigation . Communities of Pythium, Fusarium, and Rhizoctonia . Soil bioassay . Dilution plating . DGGE . DNA sequence analysis
Introduction Seed-rot, root-rot, and damping-off is a disease complex that leads to the decay of germinating seeds and death of young seedlings, which is one of the major constraints to soybean (Glycine max (L.) Merr) production in the United States (Allen et al. 2017). A total yield loss in the United States owing to root and seedling diseases was estimated to be 6.6 million metric tons in 2014 (Allen et al. 2017). The disease was mainly caused by the infection of a complex consisting of Pythium, Fusarium, Rhizoctonia, and Phytophthora spp., either singly or in combination. These
Data Loading...
