Soil fumigation with ammonium bicarbonate or metam sodium under high temperature alleviates continuous cropping-induced Fusarium wilt in watermelon

Tomato (Lycopersicon esculentum Mill.) was grown to evaluate various chemicals as possible alternatives to methyl bromide soil fumigation. Due to a combination of weeds, nematodes, and soil fungi, the use of a broad-spectrum fumigant has been essential for economical tomato production in Florida. Methyl bromide (MBr) and combinations of MBr with chloropicrin (Pic) are the fumigants of choice for most growers using polyethylene mulch culture. In 1991, MBr was allegedly associated with stratospheric ozone depletion. The U.S. Environmental Protection Agency has since mandated a phaseout of MBr for soil fumigation in the United States by the year 2001. At three locations in Florida, alternative soil fumigants were evaluated, including soil injected 98% MBr—2% Pic at 450 kg·ha-1, 67% MBr—33% Pic (390 kg·ha-1), Pic (390 kg·ha-1), dichloropropene + 17% Pic (1,3-D + Pic) at 327 L·ha-1, and metam-sodium (935 L·ha-1). Also, metam-sodium and tetrathiocarbonate (1870 L·ha-1) were applied by drip irrigation. Dazomet (450 kg·ha-1) was surface applied and soil incorporated. Pebulate (4.5 kg·ha-1) was soil incorporated with some treatments. Pic and 1,3-D + Pic treatments provided good to moderate control of nematodes and soil fungi except in one of the six studies, in which nematode control with 1,3-D was moderate to poor. Nutsedge densities were suppressed by addition of pebulate. Tomato fruit yields with 1,3-D + Pic + pebulate and with Pic + pebulate at the three sites ranged from 85% to 114%, 60% to 95%, and l01% to 119%, respectively, of that obtained with MBr treatments. Pest control and crop yield were lower with treatments other than the above pebulate-containing or MBr-containing treatments. These studies indicate that no one alternative pesticide can provide the consistent broad-spectrum control provided by MBr. Chemical names used: trichloronitromethane (chloropicrin); 1,3-dichloropropene (1,3-D); sodium N-methyldithiocarbamate (metam-sodium); sodium tetrathiocarbonate (tetrathiocarbonate); 3,5-dimethyl-(2H)-tetrahydro-l,3,5-thiadiazine-2-thione (dazomet); S-propyl butyl(ethyl)thiocarbamate (pebulate).

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The grafting of triploid watermelon is an advantageous alternative to soil fumigation by methyl bromide for control of Fusarium wilt

Scientia Horticulturae ◽

10.1016/j.scienta.2004.04.007 ◽

2004 ◽

Vol 103 (1) ◽

pp. 9-17 ◽

Cited By ~ 73

Author(s):

A. Miguel ◽

J.V. Maroto ◽

A. San Bautista ◽

C. Baixauli ◽

V. Cebolla ◽

...

Keyword(s):

Fusarium Wilt ◽

Methyl Bromide ◽

Soil Fumigation ◽

Triploid Watermelon

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Possible mechanisms of control of Fusarium wilt of cut chrysanthemum by Phanerochaete chrysosporium in continuous cropping fields: A case study

Scientific Reports ◽

10.1038/s41598-017-16125-7 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 7

Author(s):

Ping Li ◽

Jingchao Chen ◽

Yi Li ◽

Kun Zhang ◽

Hailei Wang

Keyword(s):

Phanerochaete Chrysosporium ◽

Fusarium Wilt ◽

Continuous Cropping

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Drip Application of Alternative Fumigants to Methyl Bromide for Strawberry Production

HortScience ◽

10.21273/hortsci.39.7.1707 ◽

2004 ◽

Vol 39 (7) ◽

pp. 1707-1715 ◽

Cited By ~ 28

Author(s):

Husein A. Ajwa ◽

Thomas Trout

Keyword(s):

Methyl Bromide ◽

Irrigation Water ◽

Drip Irrigation ◽

Developed Countries ◽

Soil Fumigation ◽

Fruit Yield ◽

Methyl Isothiocyanate ◽

Irrigation Systems ◽

Metam Sodium ◽

Pathogen Populations

Strawberry (Fragaria ×ananassa Duchesne) is a high-value cash crop that benefits from preplant soil fumigation with methyl bromide (MB) and chloropicrin (CP). Methyl bromide will be banned in the U.S. and other developed countries by 2005 for most uses. Potential alternative chemicals to replace methyl bromide for soil fumigation include CP, 1,3-dichloropropene (1,3-D), and methyl isothiocyanate (MITC) generators such as metam sodium (MS). Commercial formulations of these fumigants applied singly and in combination through drip irrigation systems were evaluated at two sites for three consecutive growing seasons as alternatives to MB:CP fumigation for strawberry production. A mixture of 1,3-D and CP was shank injected as Telone C35 (62% 1,3-D and 35% CP) at 374 kg·ha-1. An emulsifiable concentrate (EC) formulation of 1,3-D and CP was applied as InLine (60% 1,3-D and 32% CP) at 236 and 393 L·ha-1 through drip irrigation systems in three amounts of irrigation water (26, 43, and 61 L·m-2). Chloropicrin (CP EC, 96%) was drip applied singly at 130 or 200 L·ha-1. Metam sodium was applied singly as Vapam HL in three amounts of water and in combination with InLine and CP EC. Strawberry growth, fruit yields, disease pressure, and weed biomass were compared to an untreated control and shank injection with MB:CP mixture (67:33) at 425 kg·ha-1. For soils high in pathogen populations, fruit yield from the untreated plots was 34% to 50% relative to the MB:CP treatment. The greatest (95% to 110%) yields relative to MB:CP were in the high rates of the InLine treatments. Yields from simultaneous drip fumigation with a combination of Vapam HL and InLine or CP EC were less (67% to 79%) than yields from shank fumigation with MB:CP due to 1,3-D and CP hydrolysis reactions with Vapam HL or the generated MITC in the irrigation water that reduced the efficacy of these combinations to control soilborne pathogens. Application of reduced rates of InLine or CP EC followed 6 days later with reduced rates of Vapam HL controlled soil borne pathogens and weeds and produced the greatest fruit yield relative to all treatments. Chemical names used: 1,3-dichloropropene (1,3-D); methyl bromide (MB); trichloronitromethane (chloropicrin, CP); sodium methyldithiocarbamate (metam sodium); methyl isothiocyanate (MITC).

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Soil inoculation of Trichoderma asperellum M45a regulates rhizosphere microbes and triggers watermelon resistance to Fusarium wilt

10.21203/rs.3.rs-36823/v1 ◽

2020 ◽

Author(s):

Yi Zhang ◽

Cheng Tian ◽

Jiling Xiao ◽

Lin Wei ◽

Yun Tian ◽

...

Keyword(s):

Fusarium Wilt ◽

Relative Abundance ◽

Average Length ◽

Plant Growth Promoting Rhizobacteria ◽

Continuous Cropping ◽

Trichoderma Asperellum ◽

Control Effect ◽

Total N ◽

P Transformation ◽

Plant Growth Promoting

Abstract Fusarium wilt (FW) caused by Fusarium oxysporum f. sp. niveum (FON) is a soil-borne disease that seriously limits watermelon production. In the present study, the Trichoderma asperellum (T. asperellum) M45a was shown to be an effective biocontrol agent against Fusarium wilt (FW). In a pot experiment, the application of 105 cfu/g of T. asperellum M45a granules had better control effect on FW at the blooming period (up to 67.44%) from soils subjected to five years of continuous cropping with watermelon, while the average length of watermelon vine was also significantly improved(P < 0.05). Additionally, the acid phosphatase (ACP), cellulase (CL), catalase (CAT) and sucrase (SC) activities in the M45a-inoculation group were significantly higher than in the control (CK) group, and the soil nutrients (total N, NO3-N, and available P) transformation was significantly increased. Moreover, T. asperellum M45a inoculation reduced fungal diversity and increased bacterial diversity, especially enhancing the relative abundance of PGPR (plant growth promoting rhizobacteria), such as Trichoderma, Sphingomonas, Pseudomonas, Actinomadura and Rhodanobacter. Through functional prediction, the relative abundance of Ectomycorrhizal, Endophyte, Animal pathotroph and saprotroph in fungal community was determined to be significantly lower than observed in the M45a-treated soil. Correlation analysis revealed that Sphingomonas, Pseudomonas and Trichoderma had the most differences in microorganisms abundance, positively correlated with ACP, CL, CAT and SC. These findings will provide ecological fungicide advice for microecological control of FW in continuous cropping watermelon.

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Synergistic Effect of Dazomet Soil Fumigation and Clonostachys rosea Against Cucumber Fusarium Wilt

Phytopathology ◽

10.1094/phyto-11-13-0297-r ◽

2014 ◽

Vol 104 (12) ◽

pp. 1314-1321 ◽

Cited By ~ 11

Author(s):

Tian Tian ◽

Shi-Dong Li ◽

Man-Hong Sun

Keyword(s):

Synergistic Effect ◽

Fusarium Wilt ◽

Disease Incidence ◽

Soil Fumigation ◽

Control Measures ◽

Clonostachys Rosea ◽

Synergistic Mechanism ◽

Colonization Potential ◽

Sporulation Rate ◽

Cucumber Fusarium Wilt

Soil fumigation and biological control are two control measures frequently used against soilborne diseases. In this study, the chemical fumigant dazomet was applied in combination with the biocontrol agent (BCA) Clonostachys rosea 67-1 to combat cucumber wilt caused by Fusarium oxysporum f. sp. cucumerinum KW2-1. When the mycoparasite C. rosea 67-1 was applied after dazomet fumigation, disease control reached 100%, compared with 88.1 and 69.8% for dazomet and 67-1 agent, respectively, applied alone, indicating a synergistic effect of dazomet and C. rosea in combating cucumber Fusarium wilt based on analysis of Bliss Independence. To understand the synergistic mechanism, the effects of chemical fumigation on the colonization potential and activity of F. oxysporum f. sp. cucumerinum, and the interaction between the BCA and the pathogen were investigated. The results showed that growth of the pathogen decreased with increasing dazomet concentration subsequent to fumigation. When exposed to dazomet at 100 ppm, the fungal sporulation rate decreased by 94.4%. Severe damage was observed in fumigated isolates using scanning electron microscopy. In the greenhouse, disease incidence of cucumber caused by fumigated F. oxysporum f. sp. cucumerinum significantly decreased. Whereas germination of C. rosea 67-1 spores increased by >sixfold in fumigated soil, and its ability to parasitize fumigated F. oxysporum f. sp. cucumerinum significantly increased (P = 0.014).

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Community Structures and Antifungal Activity of Root-Associated Endophytic Actinobacteria in Healthy and Diseased Cucumber Plants and Streptomyces sp. HAAG3-15 as a Promising Biocontrol Agent

Microorganisms ◽

10.3390/microorganisms8020236 ◽

2020 ◽

Vol 8 (2) ◽

pp. 236 ◽

Cited By ~ 3

Author(s):

Peng Cao ◽

Chenxu Li ◽

Han Wang ◽

Zhiyin Yu ◽

Xi Xu ◽

...

Keyword(s):

Antifungal Activity ◽

Plant Growth ◽

Fusarium Wilt ◽

Broad Spectrum ◽

Biocontrol Agent ◽

Infected Plant ◽

Rrna Gene ◽

Continuous Cropping ◽

Genus Streptomyces ◽

Cucumber Roots

Microorganisms related to plant roots are vital for plant growth and health and considered to be the second genome of the plant. When the plant is attacked by plant pathogens, the diversity and community structure of plant-associated microbes might be changed. The goal of this study is to characterize differences in root-associated endophytic actinobacterial community composition and antifungal activity between Fusarium wilt diseased and healthy cucumber and screen actinobacteria for potential biological control of Fusarium wilt of cucumber. In the present research, three healthy plants (also termed “islands”) and three obviously diseased plants (naturally infected by F. oxysporum f. sp. cucumerinum) nearby the islands collected from the cucumber continuous cropping greenhouse were chosen as samples. Results of culture-independent and culture-dependent analysis demonstrated that actinomycetes in the healthy roots were significantly more abundant than those of diseased roots. Moreover, there were seven strains with antifungal activity against F. oxysporum f. sp. cucumerinum in healthy cucumber roots, but only one strain in diseased cucumber roots. Out of these eight strains, the isolate HAAG3-15 was found to be best as it had the strongest antifungal activity against F. oxysporum f. sp. cucumerinum, and also exhibited broad-spectrum antifungal activity. Thus, strain HAAG3-15 was selected for studying its biocontrol efficacy under greenhouse conditions. The results suggested that the disease incidence and disease severity indices of cucumber Fusarium wilt greatly decreased (p < 0.05) while the height and shoot fresh weight of cucumber significantly increased (p < 0.05) after inoculating strain HAAG3-15. On the basis of morphological characteristics, physiological and biochemical properties and 100% 16S ribosomal RNA (rRNA) gene sequence similarity with Streptomyces sporoclivatus NBRC 100767T, the isolate was assigned to the genus Streptomyces. Moreover, azalomycin B was isolated and identified as the bioactive compound of strain HAAG3-15 based on analysis of spectra using a bioactivity-guided method. The stronger antifungal activity against F. oxysporum f. sp. cucumerinum, the obvious effect on disease prevention and growth promotion on cucumber seedlings in the greenhouse assay, and the excellent broad-spectrum antifungal activities suggest that strain HAAG3-15 could be developed as a potential biocontrol agent against F. oxysporum f. sp. cucumerinum used in organic agriculture. These results suggested that the healthy root nearby the infected plant is a good source for isolating biocontrol and plant growth-promoting endophytes.

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