Inhibition of <i>Pythium</i> spp. and Suppression of Pythium Blight of Turfgrasses with Phosphonate Fungicides

Cook, Philip J.; Landschoot, Peter J.; Schlossberg, Maxim J.

doi:10.1094/pdis-93-8-0809

Cited by 29 publications

(22 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In a later study, Pythium spp. were inhibited with EC 50 values between 38.7 and 220.8 μg mL −1 (Cook et al ., ). This direct mode of inhibition seems to involve disruption of the pathogen's metabolism.…”

Section: Introductionmentioning

confidence: 97%

Suppression of the in vitro growth and development of Microdochium nivale by phosphite

et al. 2018

View full text Add to dashboard Cite

The ascomycete fungus Microdochium nivale is a major pathogen of many species of the gramineae. Control measures rely heavily on chemical fungicides, making alternative means of disease reduction desirable. Phosphite (PO33−), has proven efficacy in reducing susceptibility of different species of gramineae to oomycetes, and has adverse effects on the in vitro growth of numerous other pathogens. The effect of phosphorous acid (H3PO3), phosphoric acid (H3PO4), dihydrogen potassium phosphite (KH2PO3), dihydrogen potassium phosphate (KH2PO4) and potassium hydroxide (KOH) on the in vitro mycelial growth and development of M. nivale was determined. Radial growth on amended potato dextrose agar (PDA) was used to calculate mean daily growth and percentage inhibition. PO33− had a significant inhibitory effect on mycelial growth, with EC50 values ranging between 35.9 and 40.99 μg mL−1, whilst PO43− and KOH had no significant inhibitory effect. Microscopic examination of mycelia showed morphological deformities in hyphae growing on PO33− amended PDA, whilst hyphal growth was normal on PO43− and KOH amended PDA. Conidial germination of M. nivale was significantly reduced following immersion in solutions of 50, 100 and 250 μg mL−1 of PO33−, while PO43− and KOH at the same concentrations induced no inhibitory affect. These results show that PO33− is a significant inhibitor of the growth of M. nivale and may have the potential to be used as a chemical control agent in the field.

show abstract

Section: Introductionmentioning

confidence: 97%

Suppression of the in vitro growth and development of Microdochium nivale by phosphite

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Así, mediante esa práctica se reportó disminución en el crecimiento de Alternaria alternata (Reuveni et al, 2003), Colletotrichum gloeosporioides (Araujo et al, 2010), Fusarium culmorum y F. graminearum (Hofgaard et al, 2010), Mycosphaerella digitatum (Cerioni et al, 2013), Phytophthora cinnamomi (Wilkinson et al, 2001;Won et al, 2009;King et al, 2010), P. cinnamomi, P. palmivora and P. nicotianae (Smillie et al, 1989), P. infestans (Bórza et al, 2014), P. plurivora (Dalio et al, 2014) and Pythium aphanidermatum, P. ultimum, P. irregulare, P. myriotylum, P. torulosum, P. volutum and P. graminicola (Cook et al, 2009). The decrease level in the microorganisms' growth as a consequence of the phosphite ion is determined by the organism tested, amount of phosphite added to the culture medium, type of ion bonded to phosphite and pH produced by the culture medium (Lobato et al, 2010).…”

Section: Acción Directamentioning

confidence: 99%

“…The susceptibility of the microorganisms to the phosphite ion was demonstrated by Wong et (Cerioni et al, 2013), Phytophthora cinnamomi (Wilkinson et al, 2001;Won et al, 2009;King et al, 2010), P. cinnamomi, P. palmivora y P. nicotianae (Smillie et al, 1989), P. infestans (Bór-za et al, 2014), P. plurivora (Dalio et al, 2014) y Pythium aphanidermatum, P. ultimum, P. irregulare, P. myriotylum, P. torulosum, P. volutum y P. graminicola (Cook et al, 2009). El grado de disminución en el crecimiento de los microorganismos como consecuencia del ion fosfito, está determinado por el organismo ensayado, la cantidad de fosfito agregado al medio de cultivo, el tipo de ion unido al fosfito y el pH que se origine en el medio de cultivo (Lobato et al, 2010).…”

Section: Acción Directaunclassified

“…Smillie et al (1989) determinaron la susceptibilidad de Phytophthora cinnamomi, P. palmivora y P. nicotiana a fosfito de potasio, explicando además que a medida que la concentración de fosfito se incrementó en el medio de cultivo, disminuyó el peso de la biomasa producida por las tres especies de Phytophthora. También Cook et al (2009) evaluaron la concentración necesaria de fosfito y el fungicida mefenoxan, para inhibir el 50% del crecimiento del micelio de ocho aislamientos de Pythium aphanidermatum, y reportaron que todos los aislamientos fueron susceptibles a los dos compuestos, pero que las concentraciones de fosfito utilizadas fueron mayores que las del fungicida.…”

Section: Acción Directaunclassified

“…Smillie et al (1989) showed Phytophthora cinnamomi, P. palmivora and P. nicotiana susceptibility to potassium phosphite, and explained that as the concentration of phosphite increased in the culture medium, the weight of the biomass produced by Phytophthora species decreased. Cook et al (2009) also evaluated the concentration of phosphite and mefenoxan fungicide needed to inhibit 50% mycelium growth of eight Pythium aphanidermatum isolates, and reported that all the isolates were susceptible to both compounds, but that the concentrations of phosphite were higher than those of the fungicide.…”

Section: Acción Directamentioning

confidence: 99%

See 2 more Smart Citations

Los fosfitos como alternativa para el manejo de problemas fitopatológicos

Juárez

Orona

Ayala-Tafoya

et al. 2018

RMF

View full text Add to dashboard Cite

Resumen. Los fosfitos son compuestos deriva-dos del ácido fosforoso empleados como alternativa para el control de organismos fitoparásitos y su eficacia se ha probado contra protozoarios, oomycetes, hongos, bacterias y nematodos; sin embargo, en comparación con los fungicidas convencionales sintetizados, generalmente son menos eficaces para disminuir el daño por fitopatógenos. El ion fosfito es fácilmente transportado en las plantas vía xilema y floema, por lo que se ha utilizado en aplicación foliar, baño a la raíz y cuello de la planta, inyección al tronco, a través de riego por goteo mezclado en la solución nutritiva en hidroponía, tratamiento a semilla, aplicación aérea en bajo volumen o como tratamiento en inmersión de semillas y frutos. Los Abstract. Phosphites are compounds derived from phosphorous acid used as an alternative for the control of phytoparasitic organisms and their effectiveness has been tested against protozoa, oomycetes, fungi, bacteria and nematodes; however, compared to conventional synthesized fungicides, phosphites are generally less effective at reducing damage by phytopathogens. The phosphite ion is easily transported in the plants via xylem and phloem, so it has been used in foliar application, drench of plant root and neck, injection trunk, through drip irrigation mixed in the nutrient solution in hydroponics, seed treatment, aerial application in low volume, or as treatment in immersion of seeds and fruits. The mechanisms of action involved in the prophylactic effects of phosphites are diverse and include the stimulation of biochemical and structural defense mechanisms in plants and direct action that restricts the growth, development and reproduction of phytopathogenic organisms. Phosphites as alternative for the management of phytopathological problems

show abstract

Iron sulfate and phosphite products fail to suppress snow mold on amenity turfgrass in Wisconsin

Koch

2021

Crop Forage & Turfgrass Mgmt

View full text Add to dashboard Cite

Snow molds are an important group of diseases of amenity turfgrass in temperate climates. Acceptable control is typically achieved through one or two fungicide applications prior to snow cover, though there is increasing interest in exploring alternative control products such as iron sulfate and/or potassium phosphite. Previous research has demonstrated that poor snow mold control is achieved when these alternative products are applied once prior to snow cover, so the objective of this study was to assess their efficacy when applied repeatedly throughout the fall. Iron sulfate heptahydrate, potassium phosphite, and the fungicide propiconazole were applied six times, every 2 weeks, throughout the fall of 2019 at three locations in Wisconsin that typically produce high, medium, and low snow mold pressure. No reduction in disease relative to the nontreated control was observed at any location in response to the iron sulfate and potassium phosphite treatments. Propiconazole did provide effective snow mold control at the low and moderate pressure locations but not at the high pressure location. Both iron sulfate and potassium phosphite have shown efficacy against select turfgrass diseases, but do not appear to provide control of snow mold in areas where snow cover persists during winter. INTRODUCTIONSnow molds such as Microdochium patch (caused by Microdochium nivale), gray snow mold (Typhula incarnata), and speckled snow mold (Typhula ishikariensis) are the primary low-temperature diseases of amenity turfgrass around the world (Hsiang et al., 1999;Mann & Newell, 2005). Microdochium patch, also known as pink snow mold, is defined by roughly circular patches of tan-or reddish-colored turf 2-8 inches (5-20 cm) in diameter. Symptoms are typically most severe under prolonged snow cover but can also occur in the absence of snow following periods of cool (32-48 ˚F) and wet weather. The presence of a pink-colored ring Abbreviation: HDD, heating degree day.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

show abstract

Inhibition of Pythium spp. and Suppression of Pythium Blight of Turfgrasses with Phosphonate Fungicides

Cited by 29 publications

References 10 publications

Suppression of the in vitro growth and development of Microdochium nivale by phosphite

Suppression of the in vitro growth and development of Microdochium nivale by phosphite

Los fosfitos como alternativa para el manejo de problemas fitopatológicos

Iron sulfate and phosphite products fail to suppress snow mold on amenity turfgrass in Wisconsin

Contact Info

Product

Resources

About