Carbon Source and Soil Origin Shape Soil Microbiomes and Tomato Soilborne Pathogen Populations During Anaerobic Soil Disinfestation

Soilborne disease complexes are an emerging constraint in protected culture tomato production systems in the Midwestern United States. Diseases in these complexes include Verticillium wilt (Verticillium dahliae), black dot root rot (Colletotrichum coccodes), corky root rot (Pyrenochaeta lycopersici), and root knot (Meloidogyne spp.). Anaerobic soil disinfestation (ASD) may be a viable, environmentally benign strategy for managing these complexes. Soils from two farms in Ohio were used to determine the impacts of ASD, using wheat bran, molasses, or ethanol as carbon sources, on soilborne diseases and soil bacterial communities. ASD with wheat bran or ethanol amendments led to significantly reduced tomato root rot severity, while nematode galling damage was significantly reduced following ASD with any carbon source compared with nontreated controls. When ethanol was used as a carbon source in ASD, the colonization of tomato roots by P. lycopersici and C. coccodes was observed less frequently than in control roots. A high throughput sequencing approach was used to characterize soil bacterial communities following ASD. Carbon source and soil origin influenced the composition of bacterial communities in soils treated with ASD. Bacterial community diversity decreased following ASD with wheat bran in all soils tested and following ASD with ethanol in soils from one farm. The abundance of bacteria in the phylum Firmicutes generally increased significantly following ASD, while the abundance of those in the phyla Acidobacteria, Actinobacteria, Chloroflexi, and Plantomycetes generally decreased following ASD. These findings provide insight into the impacts of ASD on microbial communities and soilborne diseases and will be used to optimize ASD as a tool for Midwestern vegetable growers.

Download Full-text

Shifts in Soil Bacterial Communities as a Function of Carbon Source Used During Anaerobic Soil Disinfestation

Frontiers in Environmental Science ◽

10.3389/fenvs.2018.00160 ◽

2019 ◽

Vol 6 ◽

Cited By ~ 11

Author(s):

Amisha T. Poret-Peterson ◽

Sebastian Albu ◽

Ali E. McClean ◽

Daniel A. Kluepfel

Keyword(s):

Carbon Source ◽

Bacterial Communities ◽

Soil Disinfestation ◽

Anaerobic Soil Disinfestation ◽

Soil Bacterial Communities ◽

Soil Bacterial

Download Full-text

Synergy of Anaerobic Soil Disinfestation and Trichoderma spp. in Rhizoctonia Root Rot Suppression

Frontiers in Sustainable Food Systems ◽

10.3389/fsufs.2021.645736 ◽

2021 ◽

Vol 5 ◽

Author(s):

Ram B. Khadka ◽

Sally A. Miller

Keyword(s):

Carbon Source ◽

Rhizoctonia Solani ◽

Wheat Bran ◽

Root Rot ◽

Carbon Sources ◽

Chicken Manure ◽

Treated Soil ◽

Soil Disinfestation ◽

Anaerobic Soil Disinfestation ◽

Rhizoctonia Root Rot

Potential synergy between anaerobic soil disinfestation (ASD) and Trichoderma spp. in suppression of Rhizoctonia root rot in radish was evaluated. A split-plot design with three replications was used; main plots were Trichoderma harzianum T22, Trichoderma asperellum NT25 and a non-Trichoderma control. Subplots were ASD carbon sources wheat bran, molasses, chicken manure, and mustard greens and two non-amended controls: anaerobic (covered and flooded) and aerobic (not covered or flooded). Carbon sources and Rhizoctonia solani inoculant were mixed with soil, placed in pots, and flooded, followed by drenching Trichoderma spore suspensions and sealing the pots in zip-lock bags. After 3 weeks, bags were removed, soil was aired for 1 week and radish “SSR-RR-27” was seeded. Rhizoctonia root rot severity and incidence were lowest in radish plants grown in ASD-treated soil amended with wheat bran, molasses, or mustard greens across all Trichoderma treatments. Disease severity was lower in radish plants treated with NT25 than with T22 or the non-Trichoderma control across all ASD treatments, and in radish grown in ASD-treated soil amended with wheat bran plus NT25 compared to ASD-wheat bran or NT25 alone. Rhizoctonia solani populations were significantly reduced by ASD treatment regardless of carbon source, while Trichoderma populations were not affected by ASD treatment with the exception of ASD-mustard greens. The interactions of either Trichoderma isolate and ASD with most carbon sources were additive, while T22 with ASD-molasses and NT25 with ASD–wheat bran interactions were synergistic in reducing disease severity. One interaction, T22 with ASD-chicken manure was antagonistic. Enhancement of ASD efficacy in suppressing soilborne diseases such as Rhizoctonia root rot by additional soil amendment with Trichoderma spp. during the process appears to be dependent on both Trichoderma isolate and ASD carbon source.

Download Full-text

Anaerobic Soil Disinfestation Reduces Viability of Sclerotinia sclerotiorum and S. minor Sclerotia and Root-Knot Nematodes in Muck Soils

Phytopathology ◽

10.1094/phyto-10-19-0386-r ◽

2020 ◽

Vol 110 (4) ◽

pp. 795-804

Author(s):

Andres D. Sanabria-Velazquez ◽

Anna L. Testen ◽

Ram B. Khadka ◽

Zhe Liu ◽

Fuqing Xu ◽

...

Keyword(s):

Carbon Source ◽

Sclerotinia Sclerotiorum ◽

Wheat Bran ◽

Carbon Sources ◽

Ethanol Solution ◽

Meloidogyne Hapla ◽

Root Knot Nematodes ◽

Soil Disinfestation ◽

Anaerobic Soil Disinfestation ◽

Muck Soil

Experiments were conducted to evaluate potential functional and mechanistic differences in the suppression of Sclerotinia sclerotiorum and S. minor and root-knot nematodes in muck soils by anaerobic soil disinfestation (ASD) using different carbon source amendments. Volatile compounds produced during ASD in muck soil amended with molasses, wheat bran, or mustard greens at 20.2 Mg/ha or a 2% ethanol solution significantly reduced the mycelial growth and number of sclerotia produced by both Sclerotinia spp. compared with the anaerobic control. In amended soils, acetic and butyric acids were detected in concentrations that reduced the viability of sclerotia of both pathogens. Higher concentrations of carbon dioxide were observed in ASD-treated soils, regardless of the amendment, than in the nonamended anaerobic control. Only amendment with wheat bran did not increase the production of methane gas during ASD compared with the controls. Meloidogyne hapla survival was completely suppressed in soils treated with ASD regardless of carbon source. Field trials were conducted in Ohio muck soil to assess survival of sclerotia of both Sclerotinia spp. The viability of sclerotia of both Sclerotinia spp. was significantly reduced in soil subjected to ASD amended with wheat bran (20.2 Mg/ha), molasses (10.1 Mg/ha), or wheat bran (20.2 Mg/ha) plus molasses (10.1 Mg/ha) compared with the controls. A consistent negative correlation between soil reduction and viability of sclerotia of both pathogens was observed. Wheat bran and molasses are both widely available amendments that can be used as ASD carbon sources for the management of soilborne pathogens in muck soils.

Download Full-text

Effects of inoculation with organic-phosphorus-mineralizing bacteria on soybean (Glycine max) growth and indigenous bacterial community diversity

Canadian Journal of Microbiology ◽

10.1139/cjm-2016-0758 ◽

2017 ◽

Vol 63 (5) ◽

pp. 392-401 ◽

Cited By ~ 3

Author(s):

Wei Sun ◽

Xun Qian ◽

Jie Gu ◽

Xiao-Juan Wang ◽

Yang Li ◽

...

Keyword(s):

Glycine Max ◽

Carbon Source ◽

Bacterial Community ◽

Bacterial Communities ◽

Organic Phosphorus ◽

Community Diversity ◽

Carbon Source Utilization ◽

Soil Bacterial Communities ◽

Bacterial Community Diversity ◽

Soil Bacterial

Three different organic-phosphorus-mineralizing bacteria (OPMB) strains were inoculated to soil planted with soybean (Glycine max), and their effects on soybean growth and indigenous bacterial community diversity were investigated. Inoculation with Pseudomonas fluorescens Z4-1 and Brevibacillus agri L7-1 increased organic phosphorus degradation by 22% and 30%, respectively, compared with the control at the mature stage. Strains P. fluorescens Z4-1 and B. agri L7-1 significantly improved the soil alkaline phosphatase activity, average well color development, and the soybean root activity. Terminal restriction fragment length polymorphism analysis demonstrated that P. fluorescens Z4-1 and B. agri L7-1 could persist in the soil at relative abundances of 2.0%–6.4% throughout soybean growth. Thus, P. fluorescens Z4-1 and B. agri L7-1 could potentially be used in organic-phosphorus-mineralizing biofertilizers. OPMB inoculation altered the genetic structure of the soil bacterial communities but had no apparent influence on the carbon source utilization profiles of the soil bacterial communities. Principal components analysis showed that the changes in the carbon source utilization profiles of bacterial community depended mainly on the plant growth stages rather than inoculation with OPMB. The results help to understand the evolution of the soil bacterial community after OPMB inoculation.

Download Full-text

Anaerobic Soil Disinfestation to Manage Soilborne Diseases in Muck Soil Vegetable Production Systems

Plant Disease ◽

10.1094/pdis-09-18-1578-re ◽

2019 ◽

Vol 103 (7) ◽

pp. 1757-1762 ◽

Cited By ~ 4

Author(s):

Anna L. Testen ◽

Sally A. Miller

Keyword(s):

Soil Ph ◽

Wheat Bran ◽

Production Systems ◽

Field Measurements ◽

Vegetable Production ◽

Root Knot Nematode ◽

Soilborne Diseases ◽

Soil Disinfestation ◽

Anaerobic Soil Disinfestation ◽

Muck Soil

Anaerobic soil disinfestation (ASD) was evaluated as a tool for managing the root-knot nematode Meloidogyne hapla in lettuce (Lactuca sativa) and clubroot disease, caused by Plasmodiophora brassicae, in mustard greens (Brassica juncea) produced on Ohio muck soils in Huron and Stark Counties. In two consecutive years of field trials, wheat bran (20.2 Mg ha−1), molasses (10.1 Mg ha−1), and wheat bran (20.2 Mg ha−1) plus molasses (10.1 Mg ha−1) were assessed as ASD carbon sources and compared with nonamended controls. Data were collected from plants grown in the field and from plants grown in field-treated soils in growth chamber-based post-ASD bioassays. Anaerobic conditions developed in ASD-treated soils in both trial years, as indicated by polyvinyl chloride pipes painted with an iron oxide paint. Soil pH did not decrease during ASD at the Huron County site of the mustard greens clubroot trials in either trial year but soil pH decreased significantly during ASD in Stark County soils treated with ASD with either wheat bran or wheat bran plus molasses compared with control soils in both trial years. Impacts of ASD on plant biomass were inconsistent in direct field measurements; however, significantly higher biomasses were observed in lettuce and mustard greens grown in bioassay soils collected from plots treated with ASD with wheat bran-based amendments compared with plants grown in soils from control plots. Based on direct field measurements and bioassays, the use of ASD with any carbon source led to significant reductions in root-knot nematode galling on lettuce compared with controls. Reductions in clubroot severity in mustard greens following ASD were less consistent; however, significant reductions in clubroot severity were observed in the field in one trial year and in both years of bioassays. The results of these studies indicate that ASD is a promising tool for managing soilborne diseases in muck soil vegetable production systems.

Download Full-text

Changes and recovery of soil bacterial communities influenced by biological soil disinfestation as compared with chloropicrin-treatment

AMB Express ◽

10.1186/2191-0855-3-46 ◽

2013 ◽

Vol 3 (1) ◽

pp. 46 ◽

Cited By ~ 28

Author(s):

Subrata Mowlick ◽

Takashi Inoue ◽

Toshiaki Takehara ◽

Nobuo Kaku ◽

Katsuji Ueki ◽

...

Keyword(s):

Bacterial Communities ◽

Soil Disinfestation ◽

Soil Bacterial Communities ◽

Biological Soil Disinfestation ◽

Soil Bacterial

Download Full-text

Suppression of spinach wilt disease by biological soil disinfestation incorporated with Brassica juncea plants in association with changes in soil bacterial communities

Crop Protection ◽

10.1016/j.cropro.2013.08.012 ◽

2013 ◽

Vol 54 ◽

pp. 185-193 ◽

Cited By ~ 33

Author(s):

Subrata Mowlick ◽

Hitoshi Yasukawa ◽

Takashi Inoue ◽

Toshiaki Takehara ◽

Nobuo Kaku ◽

...

Keyword(s):

Brassica Juncea ◽

Bacterial Communities ◽

Wilt Disease ◽

Soil Disinfestation ◽

Soil Bacterial Communities ◽

Biological Soil Disinfestation ◽

Soil Bacterial

Download Full-text

Effects of Anaerobic Soil Disinfestation on Sclerotinia sclerotiorum in Paraguay

Plant Health Progress ◽

10.1094/php-12-18-0082-rs ◽

2019 ◽

Vol 20 (1) ◽

pp. 50-60

Author(s):

Andres D. Sanabria-Velazquez ◽

Anna L. Testen ◽

Guillermo A. Enciso ◽

Laura C. Soilan ◽

Sally A. Miller

Keyword(s):

Carbon Source ◽

Sclerotinia Sclerotiorum ◽

Wheat Bran ◽

Carbon Sources ◽

Significant Negative Correlation ◽

Field Trials ◽

Plastic Mulch ◽

Soil Disinfestation ◽

Anaerobic Soil Disinfestation ◽

Reducing Conditions

The effects of anaerobic soil disinfestation (ASD) on Sclerotinia sclerotiorum sclerotia viability was tested in four field trials in Paraguay. Plots were amended with wheat bran (20.2 Mg/ha), molasses (10.1 Mg/ha), or wheat bran (20.2 Mg/ha) plus molasses (10.1 Mg/ha), saturated with water, and covered with black plastic mulch for 3 weeks. Control plots were not amended but were saturated and either covered (anaerobic control) or maintained uncovered (aerobic control). Tubes painted with iron oxide paint were placed in soils to assess soil reducing conditions. Sclerotia were buried 6 cm deep in treated and control soils along with temperature data loggers. After 3 weeks, the viability of sclerotia was significantly lower in all ASD-treated soils (4 to 52%) compared with the aerobic control soil (100%), regardless of the carbon source used. Sclerotial viability was also significantly reduced compared with anaerobic controls at three sites, depending on the carbon source used. A significant negative correlation between soil reducing conditions and sclerotia viability was observed at all sites. Wheat bran and molasses are widely available and inexpensive in Paraguay, and ASD with these carbon sources provides smallholder South American vegetable farmers with a new option for sustainable management of Sclerotinia and potentially other soilborne pathogens.

Download Full-text