The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform

Robert P. Larkin - One of the best experts on this subject based on the ideXlab platform.

  • Cumulative and residual effects of different potato cropping system management strategies on Soilborne Diseases and soil microbial communities over time
    Plant Pathology, 2016
    Co-Authors: Robert P. Larkin, C. W. Honeycutt, Timothy S. Griffin, O.m. Olanya, John M. Halloran
    Abstract:

    Soilborne potato Diseases and soil microbial community characteristics were evaluated over 8 years in different potato cropping systems designed to address specific management goals of soil conservation, soil improvement and Disease suppression. Results were compared to a standard rotation and non‐rotation control in field trials in Maine. Standard rotation consisted of barley underseeded with red clover, followed by potato (2‐year). Soil‐conserving system (SC) featured an additional year of forage grass and reduced tillage (3‐year, barley/timothy–timothy–potato). Soil‐improving system (SI) added yearly compost amendments to SC, and the Disease‐suppressive system (DS) featured crops with known Disease‐suppressive capability (3‐year, mustard/rapeseed–sudangrass/rye–potato). Systems were established in 2004, evaluated with and without irrigation, and actively managed until 2010, with potato also planted in 2011 and 2012 to examine residual effects. All rotations reduced Soilborne Diseases black scurf and common scab, and increased yield after one rotation cycle (3 years), but Diseases increased overall after two rotation cycles. DS maintained lower Soilborne Disease levels than all other rotations, as well as high yields, throughout the study. Cropping system effects became more pronounced after multiple cycles. SI system and irrigation both resulted in higher yields, but also higher levels of Soilborne Disease. Cropping system and irrigation effects were significant even after systems were no longer maintained. Soil microbial community data showed significant changes associated with cropping system, and differences increased over time. Cropping system strategy had significant and lasting effects on soil microbiology and Soilborne Diseases, and can be used to effectively enhance potato production.

  • Management Effects of Disease-Suppressive Rotation Crops on Potato Yield and Soilborne Disease and Their Economic Implications in Potato Production
    American Journal of Potato Research, 2014
    Co-Authors: Robert P. Larkin, John M. Halloran
    Abstract:

    Soilborne potato Diseases are persistent problems in potato production. Use of Disease-suppressive rotation crops, such as Brassica spp. (mustards, rapeseed) and sudangrass, has shown potential for management of Soilborne Diseases and enhanced yield in various crop production systems. However, how to best implement these crops into productive potato cropping systems has not yet been determined. In this research, potential Disease-suppressive crops were evaluated under four different types of production management (as a cover crop, green manure, harvested crop-residue incorporated, and harvested crop-residue not incorporated) in potato rotation field trials, and their effects on Disease, yield, and economic viability determined. Mustard blend, sudangrass, and rapeseed rotations reduced the tuber Disease black scurf (by 16–27 %) and increased yield (by 6–11 %) relative to a barley rotation control, but only mustard blend consistently reduced common scab (by 11 %). All rotation crops managed as green manures produced lower Disease (by 15–26 %) and higher yields (by 6–13 %) than other management practices. Overall, the combination of mustard blend managed as a green manure was most effective, reducing scurf by 54 % and increasing yield by 25 % relative to a soybean cover crop. The use of mustard or rapeseed as a harvested crop with incorporation provided the best economic return, increasing net income by more than $860/ha relative to the standard barley rotation, but mustard blend grown as a green manure or non-incorporated harvest crop also substantially increased net income ($600 to $780/ha). Las enfermedades de la papa en el suelo son problemas persistentes en su producción. El uso de rotación de cultivos para suprimir las enfermedades, tales como Brassica spp. (mostaza, colza) y pasto sudán, ha mostrado potencial para el manejo de las enfermedades del suelo y ha aumentado el rendimiento en varios sistemas de producción del cultivo. No obstante, aún no está determinado cómo implementar de la mejor manera estos cultivos en los sistemas productivos en el cultivo de papa. En esta investigación, se evaluaron cultivos con potencial supresivo de enfermedades bajo cuatro diferentes tipos de manejo de la producción (como cultivo de cobertura, abono verde, incorporación de residuos del cultivo después de cosecha, y residuos del cultivo no incorporados) en ensayos de campo de rotación en papa, y sus efectos en enfermedad, rendimiento, y en determinada viabilidad económica. Las rotaciones con la mezcla de mostaza, pasto sudán y colza redujeron la enfermedad de la costra negra del tubérculo (de 16–27 %) y aumentó el rendimiento (de 6–11 %) en relación a una rotación con cebada como testigo, pero la mezcla de mostaza sola redujo consistentemente la roña común (en un 11 %). Todas las rotaciones de cultivo manejadas como abonos verdes produjeron más baja enfermedad (en 15–26 %) y más altos rendimientos (de 6–13 %) que otras prácticas de manejo. En general, la combinación de la mezcla de mostaza manejada como abono verde fue la más efectiva, reduciendo la costra negra en un 54 % y aumentando el rendimiento en un 25 % en relación a un cultivo de cobertura de soya. El uso de mostaza o colza como cultivo cosechado con incorporación suministró la mejor ganancia económica, incrementando los ingresos netos por más de $ 860/ha en relación con la rotación convencional con cebada, pero la mezcla de mostaza cultivada como abono verde o como cultivo cosechado no incorporado también aumentó substancialmente el ingreso neto (de $ 600 a $ 780/ha).

  • Management Effects of Disease-Suppressive Rotation Crops on Potato Yield and Soilborne Disease and Their Economic Implications in Potato Production
    American Journal of Potato Research, 2014
    Co-Authors: Robert P. Larkin, John M. Halloran
    Abstract:

    Soilborne potato Diseases are persistent problems in potato production. Use of Disease-suppressive rotation crops, such as Brassica spp. (mustards, rapeseed) and sudangrass, has shown potential for management of Soilborne Diseases and enhanced yield in various crop production systems. However, how to best implement these crops into productive potato cropping systems has not yet been determined. In this research, potential Disease-suppressive crops were evaluated under four different types of production management (as a cover crop, green manure, harvested crop-residue incorporated, and harvested crop-residue not incorporated) in potato rotation field trials, and their effects on Disease, yield, and economic viability determined. Mustard blend, sudangrass, and rapeseed rotations reduced the tuber Disease black scurf (by 16–27 %) and increased yield (by 6–11 %) relative to a barley rotation control, but only mustard blend consistently reduced common scab (by 11 %). All rotation crops managed as green manures produced lower Disease (by 15–26 %) and higher yields (by 6–13 %) than other management practices. Overall, the combination of mustard blend managed as a green manure was most effective, reducing scurf by 54 % and increasing yield by 25 % relative to a soybean cover crop. The use of mustard or rapeseed as a harvested crop with incorporation provided the best economic return, increasing net income by more than $860/ha relative to the standard barley rotation, but mustard blend grown as a green manure or non-incorporated harvest crop also substantially increased net income ($600 to $780/ha).

  • Relative effects of biological amendments and crop rotations on soil microbial communities and Soilborne Diseases of potato
    Soil Biology and Biochemistry, 2008
    Co-Authors: Robert P. Larkin
    Abstract:

    Abstract Various biological amendments, including commercial biocontrol agents, microbial inoculants, mycorrhizae, and an aerobic compost tea (ACT), were evaluated, alone and in conjunction with different crop rotations, for their efficacy in introducing beneficial microorganisms, affecting soil microbial community characteristics (SMCC), and reducing Soilborne Diseases of potato in greenhouse and field trials in Maine. Most amendments successfully delivered microorganisms into the soil, altering microbial populations and activity in accordance with the particular organisms added, and significantly altering SMCC (as determined by FAME analysis) to various degrees from 2 to 24 weeks. Amendment effects were greatest early on (2 weeks after amendment), but effects associated with crop treatment became more dominant at subsequent assessments (10 and 24 weeks after amendment). In field trials, effects on microbial characteristics, Soilborne Diseases and tuber yield were variable, with some microbial inoculants and a biostimulant producing no significant effects, whereas arbuscular mycorrhizae, reduced stem canker and black scurf by 17–28%. When used in three different 2 yr crop rotations (barley/ryegrass, barley/clover, and potato, all followed by potato), biological amendments reduced Soilborne Disease and improved yield in some rotations, but not others. Soil-applied ACT and the combination of ACT with a mixture of beneficial microorganisms (Mix) reduced stem canker, black scurf, and common scab on tubers by 18–33% and increased yield 20–23% in the barley/ryegrass rotation, but not in the other rotations. Mix also reduced Disease (20–32%) in the barley/clover rotation only. None of the amendments significantly reduced Disease in continuous potato plots. Both crop rotation and amendment treatments significantly affected SMCC, but rotation effects were more dominant. These results indicate that certain rotations were better able to support the added beneficial organisms from amendments and enable more effective biological control, and also that favorable crop rotations may be more effective than amendments in manipulating or altering SMCC. Establishment and persistence of amendment effects may depend on many factors, but an effective and supportive crop rotation is apparently important.

  • control of Soilborne potato Diseases using brassica green manures
    Crop Protection, 2007
    Co-Authors: Robert P. Larkin, Timothy S. Griffin
    Abstract:

    Abstract Brassica crops used in crop rotations and as green manures have been associated with reductions in Soilborne pests and pathogens. These reductions have been attributed to the production of volatile sulfur compounds through a process known as biofumigation, and to changes in soil microbial community structure. In this study, selected Brassica crops, including canola, rapeseed, radish, turnip, yellow mustard, and Indian mustard, were evaluated for control of various Soilborne potato pathogens and Diseases in culture, in greenhouse trials, and in field trials on commercial potato farms. In in vitro assays, volatiles released from chopped leaf material of Brassica crops and barley inhibited growth of a variety of Soilborne pathogens of potato, including Rhizoctonia solani , Phytophthora erythroseptica , Pythium ultimum , Sclerotinia sclerotiorum , and Fusarium sambucinam , with Indian mustard resulting in nearly complete inhibition (80–100%). All Brassica crops and barley reduced inoculum levels of R. solani (20–56% reduction) in greenhouse tests, and radish, rapeseed, and Indian mustard reduced subsequent potato seedling Disease by 40–83%. In an on-farm field trial at a site with a substantial powdery scab problem, Indian mustard, rapeseed, canola, and ryegrass grown as green manure rotation crops reduced powdery scab in the subsequent potato crop by 15–40%, and canola and rapeseed reduced black scurf by 70–80% relative to a standard oats rotation. At another field site where common scab was the primary Disease problem, an Indian mustard green manure reduced common scab by 25%, and rapeseed, yellow mustard, and ‘Lemtal’ ryegrass also reduced black scurf relative to a standard ryegrass rotation. Disease reductions were not always associated with higher glucosinolate-producing crops, and were also observed with non- Brassica crops (barley and ryegrass), indicating other mechanisms and interactions are important, particularly for control of R. solani . Overall, Indian mustard was most effective for reducing powdery scab and common scab Diseases, whereas rapeseed and canola were most effective in reducing Rhizoctonia Diseases. These results indicate that Brassica crops have potential for use as green manures for the control of multiple Soilborne Disease problems.

Katherine L. Stevenson - One of the best experts on this subject based on the ideXlab platform.

  • Sensitivity of Fusarium oxysporum f. sp. niveum to Prothioconazole and Thiophanate-Methyl and Gene Mutation Conferring Resistance to Thiophanate-Methyl
    Plant Disease, 2017
    Co-Authors: Aparna Petkar, David B. Langston, James W. Buck, Katherine L. Stevenson
    Abstract:

    Fusarium wilt, incited by the fungus Fusarium oxysporum f. sp. niveum, is a Soilborne Disease that affects watermelon production worldwide. Approaches for effective management of Fusarium wilt in watermelon are limited. Studies conducted in recent years indicated that prothioconazole and thiophanate-methyl reduced the Disease significantly under field conditions. However, effects of the fungicides on different life stages of F. oxysporum f. sp. niveum and potential existence of fungicide resistance in F. oxysporum f. sp. niveum populations are unknown. In the present study, effects of prothioconazole and thiophanate-methyl on mycelium growth and spore germination of F. oxysporum f. sp. niveum isolates collected in watermelon fields in Georgia were determined. In vitro mycelium growth studies indicated that all 100 isolates evaluated were sensitive to prothioconazole; the effective concentration that suppressed mycelium growth by 50% ranged from 0.75 to 5.69 μg/ml (averaged 1.62 μg/ml). In contrast, 33 and 4% of the isolates were resistant to thiophanate-methyl at 10 and 100 μg/ml, respectively. Microconidial germination assays showed that 36 and 64% of the isolates tested were sensitive or intermediately sensitive to prothioconazole at 100 μg/ml but the fungicide did not inhibit spore germination at 10 μg/ml. Sequencing a portion of the β-tubulin gene of eight isolates resistant or sensitive to thiophanate-methyl indicated that fungicide resistance was associated with a point mutation at nucleotide position 200, resulting in a substitution of phenylalanine by tyrosine. This is the first report of isolates of F. oxysporum resistant to thiophanate-methyl. Results of the research suggest that prothioconazole may be a viable option for management of Fusarium wilt of watermelon whereas thiophanate-methyl should be used judiciously due to the existence of isolates resistant to the fungicide.

Ramsey S. Lewis - One of the best experts on this subject based on the ideXlab platform.

  • Multiple Disease Resistance Loci Affect Soilborne Disease Resistance in Tobacco (Nicotiana tabacum).
    Phytopathology, 2017
    Co-Authors: Katherine E Drake-stowe, Nicolas Bakaher, Simon Goepfert, Berangere Philippon, Regis Mark, Paul D. Peterson, Ramsey S. Lewis
    Abstract:

    Phytophthora nicotianae and Ralstonia solanacearum are two of the most important pathogens affecting tobacco worldwide. Greater insight regarding genetic systems controlling resistance to these two Soilborne pathogens, as well as identification of DNA markers associated with genomic regions controlling this resistance, could aid in variety development. An evaluation of 50 historical tobacco lines revealed a high positive correlation between resistances to the two pathogens, preliminarily suggesting that some genomic regions may confer resistance to both pathogens. A quantitative trait loci (QTL) mapping experiment designed to investigate the genetic control of Soilborne Disease resistance of highly resistant 'K346' tobacco identified four QTL significantly associated with resistance to P. nicotianae (explaining 60.0% of the observed phenotypic variation) and three QTL to be associated with R. solanacearum resistance (explaining 50.3% of the observed variation). The two QTL with the largest effect on Phytophthora resistance were also found to be the QTL with the greatest effects on resistance to Ralstonia. This finding partially explains previously observed associations between resistances to these two pathogens among U.S. current cultivars and within breeding populations. Further study is needed to determine whether these relationships are due to the same genes (i.e., pleiotropy) or favorable coupling-phase linkages that have been established over time.

  • variability for resistance to phytophthora nicotianae within a collection of nicotiana rustica accessions
    Plant Disease, 2011
    Co-Authors: Jessica M Nifong, J S Nicholson, H D Shew, Ramsey S. Lewis
    Abstract:

    Abstract Black shank, caused by Phytophthora nicotianae, is one of the most important Diseases affecting tobacco (Nicotiana tabacum) production worldwide. Many current tobacco cultivars possess immunity to race 0 of this pathogen conferred by introgressed dominant genetic factors. Novel alleles conditioning resistance to alternative races are desired. The objective of this research was to evaluate variability for black shank resistance within a collection of N. rustica germplasm using both Soilborne Disease nurseries and controlled race-specific (race 0 and race 1) inoculations. Nearly all of the 86 accessions studied exhibited very high resistance to race 0, and many displayed levels of race 1 resistance greater than that exhibited by the resistant flue-cured tobacco check, ‘K 346’. Materials found to be highly resistant to race 0 and race 1 in growth-chamber experiments also had the best survivability in field Disease nurseries. N. rustica accessions TR 6, TR 12, TR 16, TR 21, TR 20, TR 48, TR 54, TR 57...

Jianhua Guo - One of the best experts on this subject based on the ideXlab platform.

  • Table_3_Comparative Transcriptome Analysis Reveals the Biocontrol Mechanism of Bacillus velezensis F21 Against Fusarium Wilt on Watermelon.xlsx
    2019
    Co-Authors: Chunhao Jiang, Xie-feng Yao, Bing-ye Yang, Ying Zheng, Jianhua Guo
    Abstract:

    The watermelon (Citrullus lanatus) is one of the most important horticultural crops for fruit production worldwide. However, the production of watermelon is seriously restricted by one kind of Soilborne Disease, Fusarium wilt, which is caused by Fusarium oxysporum f. sp. niveum (Fon). In this study, we identified an efficient PGPR strain B. velezensis F21, which could be used in watermelon production for Fon control. The results of biocontrol mechanisms showed that B. velezensis F21 could suppress the growth and spore germination of Fon in vitro. Moreover, B. velezensis F21 could also enhance plant basal immunity to Fon by increasing the expression of plant defense related genes and activities of some defense enzymes, such as CAT, POD, and SOD. To elucidate the detailed mechanisms regulating B. velezensis F21 biocontrol of Fusarium wilt in watermelon, a comparative transcriptome analysis using watermelon plant roots treated with B. velezensis F21 or sterile water alone and in combination with Fon inoculation was conducted. The transcriptome sequencing results revealed almost one thousand ripening-related differentially expressed genes (DEGs) in the process of B. velezensis F21 triggering ISR (induced systemic resistance) to Fon. In addition, the Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment indicated that numerous of transcription factors (TFs) and plant Disease resistance genes were activated and validated by using quantitative real-time PCR (qRT-PCR), which showed significant differences in expression levels in the roots of watermelon with different treatments. In addition, genes involved in the MAPK signaling pathway and phytohormone signaling pathway were analyzed, and the results indicated that B. velezensis F21 could enhance plant Disease resistance to Fon through the above related genes and phytohormone signal factors. Taken together, this study substantially expands transcriptome data resources and suggests a molecular framework for B. velezensis F21 inducing systemic resistance to Fon in watermelon. In addition, it also provides an effective strategy for the control of Fusarium wilt in watermelon.

  • Comparative Transcriptome Analysis Reveals the Biocontrol Mechanism of Bacillus velezensis F21 Against Fusarium Wilt on Watermelon
    Frontiers Media S.A., 2019
    Co-Authors: Chunhao Jiang, Xie-feng Yao, Bing-ye Yang, Ying Zheng, Jianhua Guo
    Abstract:

    The watermelon (Citrullus lanatus) is one of the most important horticultural crops for fruit production worldwide. However, the production of watermelon is seriously restricted by one kind of Soilborne Disease, Fusarium wilt, which is caused by Fusarium oxysporum f. sp. niveum (Fon). In this study, we identified an efficient PGPR strain B. velezensis F21, which could be used in watermelon production for Fon control. The results of biocontrol mechanisms showed that B. velezensis F21 could suppress the growth and spore germination of Fon in vitro. Moreover, B. velezensis F21 could also enhance plant basal immunity to Fon by increasing the expression of plant defense related genes and activities of some defense enzymes, such as CAT, POD, and SOD. To elucidate the detailed mechanisms regulating B. velezensis F21 biocontrol of Fusarium wilt in watermelon, a comparative transcriptome analysis using watermelon plant roots treated with B. velezensis F21 or sterile water alone and in combination with Fon inoculation was conducted. The transcriptome sequencing results revealed almost one thousand ripening-related differentially expressed genes (DEGs) in the process of B. velezensis F21 triggering ISR (induced systemic resistance) to Fon. In addition, the Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment indicated that numerous of transcription factors (TFs) and plant Disease resistance genes were activated and validated by using quantitative real-time PCR (qRT-PCR), which showed significant differences in expression levels in the roots of watermelon with different treatments. In addition, genes involved in the MAPK signaling pathway and phytohormone signaling pathway were analyzed, and the results indicated that B. velezensis F21 could enhance plant Disease resistance to Fon through the above related genes and phytohormone signal factors. Taken together, this study substantially expands transcriptome data resources and suggests a molecular framework for B. velezensis F21 inducing systemic resistance to Fon in watermelon. In addition, it also provides an effective strategy for the control of Fusarium wilt in watermelon

  • Data_Sheet_1_Comparative Transcriptome Analysis Reveals the Biocontrol Mechanism of Bacillus velezensis F21 Against Fusarium Wilt on Watermelon.docx
    2019
    Co-Authors: Chunhao Jiang, Xie-feng Yao, Bing-ye Yang, Ying Zheng, Jianhua Guo
    Abstract:

    The watermelon (Citrullus lanatus) is one of the most important horticultural crops for fruit production worldwide. However, the production of watermelon is seriously restricted by one kind of Soilborne Disease, Fusarium wilt, which is caused by Fusarium oxysporum f. sp. niveum (Fon). In this study, we identified an efficient PGPR strain B. velezensis F21, which could be used in watermelon production for Fon control. The results of biocontrol mechanisms showed that B. velezensis F21 could suppress the growth and spore germination of Fon in vitro. Moreover, B. velezensis F21 could also enhance plant basal immunity to Fon by increasing the expression of plant defense related genes and activities of some defense enzymes, such as CAT, POD, and SOD. To elucidate the detailed mechanisms regulating B. velezensis F21 biocontrol of Fusarium wilt in watermelon, a comparative transcriptome analysis using watermelon plant roots treated with B. velezensis F21 or sterile water alone and in combination with Fon inoculation was conducted. The transcriptome sequencing results revealed almost one thousand ripening-related differentially expressed genes (DEGs) in the process of B. velezensis F21 triggering ISR (induced systemic resistance) to Fon. In addition, the Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment indicated that numerous of transcription factors (TFs) and plant Disease resistance genes were activated and validated by using quantitative real-time PCR (qRT-PCR), which showed significant differences in expression levels in the roots of watermelon with different treatments. In addition, genes involved in the MAPK signaling pathway and phytohormone signaling pathway were analyzed, and the results indicated that B. velezensis F21 could enhance plant Disease resistance to Fon through the above related genes and phytohormone signal factors. Taken together, this study substantially expands transcriptome data resources and suggests a molecular framework for B. velezensis F21 inducing systemic resistance to Fon in watermelon. In addition, it also provides an effective strategy for the control of Fusarium wilt in watermelon.

  • whole genome sequence of bacillus cereus ar156 a potential biocontrol agent with high Soilborne Disease biocontrol efficacy and plant growth promotion
    Genome Announcements, 2017
    Co-Authors: Chunhao Jiang, Yun Chen, Fang Yan, Zhihang Fan, Jianhua Guo
    Abstract:

    ABSTRACT Bacillus cereus AR156 was originally isolated from the forest soil of Zhenjiang, a city in China. To shed new light on the molecular mechanisms underlying the biological control of Soilborne pathogens, the whole genome of this strain was sequenced. Here, we report the draft genome sequence of this strain, consisting of a single circularized contig measuring 5.66 Mb, with an average GC content of 35.5% and 5,367 open reading frames.

Chunhao Jiang - One of the best experts on this subject based on the ideXlab platform.

  • Table_3_Comparative Transcriptome Analysis Reveals the Biocontrol Mechanism of Bacillus velezensis F21 Against Fusarium Wilt on Watermelon.xlsx
    2019
    Co-Authors: Chunhao Jiang, Xie-feng Yao, Bing-ye Yang, Ying Zheng, Jianhua Guo
    Abstract:

    The watermelon (Citrullus lanatus) is one of the most important horticultural crops for fruit production worldwide. However, the production of watermelon is seriously restricted by one kind of Soilborne Disease, Fusarium wilt, which is caused by Fusarium oxysporum f. sp. niveum (Fon). In this study, we identified an efficient PGPR strain B. velezensis F21, which could be used in watermelon production for Fon control. The results of biocontrol mechanisms showed that B. velezensis F21 could suppress the growth and spore germination of Fon in vitro. Moreover, B. velezensis F21 could also enhance plant basal immunity to Fon by increasing the expression of plant defense related genes and activities of some defense enzymes, such as CAT, POD, and SOD. To elucidate the detailed mechanisms regulating B. velezensis F21 biocontrol of Fusarium wilt in watermelon, a comparative transcriptome analysis using watermelon plant roots treated with B. velezensis F21 or sterile water alone and in combination with Fon inoculation was conducted. The transcriptome sequencing results revealed almost one thousand ripening-related differentially expressed genes (DEGs) in the process of B. velezensis F21 triggering ISR (induced systemic resistance) to Fon. In addition, the Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment indicated that numerous of transcription factors (TFs) and plant Disease resistance genes were activated and validated by using quantitative real-time PCR (qRT-PCR), which showed significant differences in expression levels in the roots of watermelon with different treatments. In addition, genes involved in the MAPK signaling pathway and phytohormone signaling pathway were analyzed, and the results indicated that B. velezensis F21 could enhance plant Disease resistance to Fon through the above related genes and phytohormone signal factors. Taken together, this study substantially expands transcriptome data resources and suggests a molecular framework for B. velezensis F21 inducing systemic resistance to Fon in watermelon. In addition, it also provides an effective strategy for the control of Fusarium wilt in watermelon.

  • Comparative Transcriptome Analysis Reveals the Biocontrol Mechanism of Bacillus velezensis F21 Against Fusarium Wilt on Watermelon
    Frontiers Media S.A., 2019
    Co-Authors: Chunhao Jiang, Xie-feng Yao, Bing-ye Yang, Ying Zheng, Jianhua Guo
    Abstract:

    The watermelon (Citrullus lanatus) is one of the most important horticultural crops for fruit production worldwide. However, the production of watermelon is seriously restricted by one kind of Soilborne Disease, Fusarium wilt, which is caused by Fusarium oxysporum f. sp. niveum (Fon). In this study, we identified an efficient PGPR strain B. velezensis F21, which could be used in watermelon production for Fon control. The results of biocontrol mechanisms showed that B. velezensis F21 could suppress the growth and spore germination of Fon in vitro. Moreover, B. velezensis F21 could also enhance plant basal immunity to Fon by increasing the expression of plant defense related genes and activities of some defense enzymes, such as CAT, POD, and SOD. To elucidate the detailed mechanisms regulating B. velezensis F21 biocontrol of Fusarium wilt in watermelon, a comparative transcriptome analysis using watermelon plant roots treated with B. velezensis F21 or sterile water alone and in combination with Fon inoculation was conducted. The transcriptome sequencing results revealed almost one thousand ripening-related differentially expressed genes (DEGs) in the process of B. velezensis F21 triggering ISR (induced systemic resistance) to Fon. In addition, the Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment indicated that numerous of transcription factors (TFs) and plant Disease resistance genes were activated and validated by using quantitative real-time PCR (qRT-PCR), which showed significant differences in expression levels in the roots of watermelon with different treatments. In addition, genes involved in the MAPK signaling pathway and phytohormone signaling pathway were analyzed, and the results indicated that B. velezensis F21 could enhance plant Disease resistance to Fon through the above related genes and phytohormone signal factors. Taken together, this study substantially expands transcriptome data resources and suggests a molecular framework for B. velezensis F21 inducing systemic resistance to Fon in watermelon. In addition, it also provides an effective strategy for the control of Fusarium wilt in watermelon

  • Data_Sheet_1_Comparative Transcriptome Analysis Reveals the Biocontrol Mechanism of Bacillus velezensis F21 Against Fusarium Wilt on Watermelon.docx
    2019
    Co-Authors: Chunhao Jiang, Xie-feng Yao, Bing-ye Yang, Ying Zheng, Jianhua Guo
    Abstract:

    The watermelon (Citrullus lanatus) is one of the most important horticultural crops for fruit production worldwide. However, the production of watermelon is seriously restricted by one kind of Soilborne Disease, Fusarium wilt, which is caused by Fusarium oxysporum f. sp. niveum (Fon). In this study, we identified an efficient PGPR strain B. velezensis F21, which could be used in watermelon production for Fon control. The results of biocontrol mechanisms showed that B. velezensis F21 could suppress the growth and spore germination of Fon in vitro. Moreover, B. velezensis F21 could also enhance plant basal immunity to Fon by increasing the expression of plant defense related genes and activities of some defense enzymes, such as CAT, POD, and SOD. To elucidate the detailed mechanisms regulating B. velezensis F21 biocontrol of Fusarium wilt in watermelon, a comparative transcriptome analysis using watermelon plant roots treated with B. velezensis F21 or sterile water alone and in combination with Fon inoculation was conducted. The transcriptome sequencing results revealed almost one thousand ripening-related differentially expressed genes (DEGs) in the process of B. velezensis F21 triggering ISR (induced systemic resistance) to Fon. In addition, the Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment indicated that numerous of transcription factors (TFs) and plant Disease resistance genes were activated and validated by using quantitative real-time PCR (qRT-PCR), which showed significant differences in expression levels in the roots of watermelon with different treatments. In addition, genes involved in the MAPK signaling pathway and phytohormone signaling pathway were analyzed, and the results indicated that B. velezensis F21 could enhance plant Disease resistance to Fon through the above related genes and phytohormone signal factors. Taken together, this study substantially expands transcriptome data resources and suggests a molecular framework for B. velezensis F21 inducing systemic resistance to Fon in watermelon. In addition, it also provides an effective strategy for the control of Fusarium wilt in watermelon.

  • whole genome sequence of bacillus cereus ar156 a potential biocontrol agent with high Soilborne Disease biocontrol efficacy and plant growth promotion
    Genome Announcements, 2017
    Co-Authors: Chunhao Jiang, Yun Chen, Fang Yan, Zhihang Fan, Jianhua Guo
    Abstract:

    ABSTRACT Bacillus cereus AR156 was originally isolated from the forest soil of Zhenjiang, a city in China. To shed new light on the molecular mechanisms underlying the biological control of Soilborne pathogens, the whole genome of this strain was sequenced. Here, we report the draft genome sequence of this strain, consisting of a single circularized contig measuring 5.66 Mb, with an average GC content of 35.5% and 5,367 open reading frames.