scholarly journals Reduced sensitivity to carbendazim in isolates of Botrytis allii

2007 ◽  
Vol 60 ◽  
pp. 108-113 ◽  
Author(s):  
S.L.H. Viljanen-Rolinson ◽  
M.V. Maroni ◽  
R.C. Butler
Keyword(s):  
New Zealand ◽  
Mycelial Growth ◽  
Management Strategy ◽  
Resistance Management ◽  
Maximum Growth ◽  
Effective Concentration ◽  
Variable Response ◽  
Growth Study ◽  
Onion Seed ◽  
Botrytis Allii

Fifty isolates of Botrytis allii causing onion botrytis neck rot were obtained from onion seed and bulbs throughout New Zealand and tested for their sensitivity to carbendazim (benzimidazole) fungicide in a mycelial growth study Agar plates amended with carbendazim at 6 or 8 different concentrations were inoculated with an 8 mm disc of mycelium of each of the isolates and incubated in the dark at 20C Radial growth of the colonies was measured after 4 days EC50 (effective concentration required to give half of maximum growth) values were estimated by fitting logistic curves with growth as a proportion of the maximum growth Of the 50 isolates 16 were identified as resistant 32 as sensitive and two had a variable response The estimated EC50 values for the isolates that were sensitive ranged from 0006 to 0053 g/ml active ingredient It is recommended that New Zealand onion growers closely follow the current benzimidazole resistance management strategy

scholarly journals Assessing the effectiveness of oxathiapiprolin towards Phytophthora agathidicida, the causal agent of kauri dieback disease

FEMS Microbes ◽  
2021 ◽  
Author(s):  
Randy F Lacey ◽  
Michael J Fairhurst ◽  
Kaitlyn J Daley ◽  
Te Amohaere Ngata-Aerengamate ◽  
Haileigh R Patterson ◽  
...  
Keyword(s):  
Life Cycle ◽  
New Zealand ◽  
Mycelial Growth ◽  
Phytophthora Species ◽  
Effective Concentration ◽  
Dependent Manner ◽  
Life Cycle Stages ◽  
Leaf Infection ◽  
Dieback Disease ◽  
Dose Dependent

Abstract Phytophthora species cause disease and devastation of plants in ecological and horticultural settings worldwide. A recently identified species, P. agathidicida, infects and ultimately kills the treasured kauri trees (Agathis australis) that are endemic to New Zealand. Currently there are few options for managing kauri dieback disease. In this study, we sought to assess the toxicity of the oomycide oxathiapiprolin against several life cycle stages of two geographically distinct P. agathidicida isolates. The effective concentration to inhibit 50% of mycelial growth (EC50) was determined to be approximately 0.1 ng/ml, indicating that P. agathidicida mycelia are more sensitive to oxathiapiprolin than those from most other Phytophthora species that have been studied. Oxathiapiprolin was also highly effective at inhibiting the germination of zoospores (EC50 = 2–9 ng/ml for the two isolates) and oospores (complete inhibition at 100 ng/ml). In addition, oxathiapiprolin delayed the onset of detached kauri leaf infection in a dose-dependent manner. Collectively, the results presented here highlight the significant potential of oxathiapiprolin as a tool to aid in the control of kauri dieback disease.

scholarly journals Assessing the effectiveness of oxathiapiprolin towards Phytophthora agathidicida, the causal agent of kauri dieback disease

2021 ◽  
Author(s):  
Randy F. Lacey ◽  
Michael J. Fairhurst ◽  
Kaitlyn J. Daley ◽  
Te Amohaere Ngata-Aerengamate ◽  
Haileigh R. Patterson ◽  
...  
Keyword(s):  
New Zealand ◽  
Mycelial Growth ◽  
Effective Concentration ◽  
Complete Inhibition ◽  
Dependent Manner ◽  
Significant Potential ◽  
Leaf Infection ◽  
Half Maximal Effective Concentration ◽  
Dieback Disease ◽  
Dose Dependent

AbstractPhytophthora species cause disease and devastation of plants in ecological and horticultural settings worldwide. A recently identified species, P. agathidicida, infects and ultimately kills the treasured kauri trees that are endemic to New Zealand. Currently there are few options for controlling or treating P. agathidicida. In this study, we sought to assess the toxicity of the oomycide oxathiapiprolin against several lifecycle stages of two geographically distinct P. agathidicida isolates. Half maximal effective concentration (EC50) values were determined to be approximately 0.1 ng/ml for inhibiting mycelial growth, indicating that P. agathidicida mycelia are more sensitive to oxathiapiprolin than those from most other Phytophthora species that have been studied. Oxathiapiprolin was also highly effective at inhibiting the germination of zoospores (EC50 = 2-9 ng/ml for the two isolates) and oospores (complete inhibition at 100 ng/ml). In addition, oxathiapiprolin delayed the onset of detached kauri leaf infection in a dose-dependent manner. Collectively, the results presented here highlight the significant potential of oxathiapiprolin as a tool to aid in the control of kauri dieback disease.

Management of collar rot disease in chickpea by Trichoderma species

2020 ◽  
Vol 7 (03) ◽  
Author(s):  
PREM PANDEY ◽  
G. C. SAGAR ◽  
SUNDARMAN SHRESTHA2 ◽  
HIRAKAJI MANANDHAR ◽  
RITESH K. YADAV ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Mycelial Growth ◽  
Sclerotium Rolfsii ◽  
Maximum Growth ◽  
Pot Experiment ◽  
Trichoderma Spp ◽  
Trichoderma Species ◽  
Collar Rot ◽  
Rot Disease

Nine isolates of Trichoderma spp. were isolated from different agro- ecological regions of Nepal viz; Jumla, Palpa, Chitwan, Tarahara, Banke, Illam and Salyan and screened against Sclerotium rolfsii Sacc. Adreded soil borne phytopathogen causing collar rot of chickpea in chickpea; In-vitro efficacy of nine fungal antagonist (Trichoderma spp.) against Sclerotium rolfsii were screened. Pot experiment was done to find out the effective management of S. rolfsi through Tricoderma using different methods i.e. Seed treatment, soil drenching and soil application. All the tested isolates of Trichoderma spp. were found effective on mycelial growth inhibition and sclerotial parasitization of S. rolfsii. Trichoderma isolated from Palpa district showed maximum growth inhibition (%) of pathogen periodically after 48(93.78%), 72(96.00%), 96(97.96%) and 120(100.00%) hours of inoculation. Parasitized sclerotium showed minimum sclerotial germination on agar plates. Moreover, Trichoderma species isolated from Palpa districts showed second best percent mycelial growth inhibition periodically at 72(25.00%), 120(29.16%), 168(29.16%) and 216(29.16%).In pot experiment at 40 days after sowing, Seedling height was maximum in soil drenching with 30g per 100ml of water (22.27cm) and Mortality percentage of seedlings was least or highest disease control was observed in seed treated with 109cfu/ml (0.000%).

Detection of oomycide-insensitive Phytophthora isolates in Maryland ornamental nurseries and Mid-Atlantic landscapes provide data for reconsidering management strategies

2021 ◽  
Author(s):  
Justine Beaulieu ◽  
Johanna Del Castillo Munera ◽  
Yilmaz Balci
Keyword(s):  
Growth Rate ◽  
Mycelial Growth ◽  
Management Strategies ◽  
Resistance Management ◽  
Phytophthora Species ◽  
Oak Forests ◽  
Relative Growth ◽  
Off Label ◽  
Potting Media ◽  
Almost All

Five Phytophthora species comprising a total of 243 isolates (77 P. cinnamomi, 23 P. citrophthora, 18 P. multivora, 18 P. pini, and 107 P. plurivora) were screened for sensitivity to mefenoxam, fosetyl-Al, dimethomorph, dimethomorph + ametoctradin and fluoxastrobin using amended agar assays. Mefenoxam-insensitive isolates were detected within P. cinnamomi (4%), P. multivora (11%), and P. plurivora (12%) even at approximately 2.5x the recommended label rate. These isolates were also insensitive to higher (off-label) concentrations of fluoxastrobin. Concentrations of dimethomorph (400 g/mL) and dimethomorph + ametoctradin (100 g/mL) were mostly effective in mycelial growth inhibition, but two P. plurivora isolates were insensitive, suggesting that resistance management is required. All mefenoxam-insensitive isolates were sensitive to fosetyl-Al at the label rate. Surprisingly, the populations of P. cinnamomi from mid-Atlantic oak forests included insensitive isolates. With almost all species, isolates recovered from asymptomatic hosts (e.g., soil/potting media collected of randomly selected asymptomatic hosts) had a significantly greater relative growth rate when compared to isolates recovered from symptomatic hosts (e.g., isolates recovered from lesions or wilted plants). These findings suggest that mefenoxam should no longer be used to manage oomycetes in Maryland ornamental nurseries and that the use of fluoxastrobin should be limited.

Botrytis allii. [Distribution map].

1978 ◽  
Author(s):  
Keyword(s):  
South Africa ◽  
Saudi Arabia ◽  
New Zealand ◽  
Central America ◽  
West Indies ◽  
Rio Grande ◽  
Rio Grande Do Sul ◽  
Distribution Map ◽  
Botrytis Allii ◽  
New Distribution

Abstract A new distribution map is provided for Botrytis allii Munn. Hosts: on Onion (Allium cepa), Leek (A. porrum), Shallot (A. ascalonicum). Information is given on the geographical distribution in AFRICA, Canary Islands, Egypt, Kenya, Morocco, South Africa, Tanzania, Zambia, ASIA, Afghanistan, China (Honan), Cyprus, Iran, Iraq, Israel, Japan, Jordan, Korea, Nepal, Pakistan, Saudi Arabia, Taiwan, Vietnam, AUSTRALASIA & OCEANIA, Australia, New Zealand, EUROPE, Austria, Belgium, Britain, Bulgaria, Denmark, Finland, France, Germany, Netherlands, Norway, Poland, Romania, USSR, Yugoslavia, NORTH AMERICA, Canada, Mexico, USA, CENTRAL AMERICA & WEST INDIES, Costa Rica, Guatemala, Panama, SOUTH AMERICA, Brazil (Rio Grande do Sul), Chile, Venezuela.

scholarly journals Detecting benzimidazole resistance in Botrytis allii using molecular techniques

2010 ◽  
Vol 63 ◽  
pp. 271-271
Author(s):  
M-I. Khan ◽  
S.R. Bulman ◽  
S.L.H. Viljanen-Rollinson ◽  
V.M. Marroni ◽  
I.A.W. Scott
Keyword(s):  
Storage Disease ◽  
Single Point ◽  
Resistance Management ◽  
Pcr Primers ◽  
Molecular Techniques ◽  
Single Point Mutation ◽  
Management Tools ◽  
Benzimidazole Fungicides ◽  
Botrytis Allii ◽  
Pcr Test

Neck rot caused by Botrytis allii is an important storage disease of onions Fungicides including benzimidazoles have been used as seed treatments and crop applications to control this disease during seed and bulb production Resistance to benzimidazole fungicides has been previously reported in B allii from New Zealand Five sensitive and five resistant isolates of the pathogen were grown in culture for DNA extraction and analysis of sequences of 946;tubulin fragments Sequence analysis revealed a single point mutation in the 946;tubulin gene in the resistant isolates PCR primers to detect the mutation were designed and tested and these clearly differentiated resistant from sensitive isolates The PCR test developed in this study will allow rapid and costeffective screening of B allii isolates to determine their sensitivity to benzimidazole fungicides The test provides technology that will assist in the development of fungicide resistance management tools for onion crops

scholarly journals Succinate dehydrogenase inhibitor (SDHI) fungicide resistance prevention strategy

2011 ◽  
Vol 64 ◽  
pp. 119-124 ◽  
Author(s):  
A.H. McKay ◽  
G.C. Hagerty ◽  
G.B. Follas ◽  
M.S. Moore ◽  
M.S. Christie ◽  
...  
Keyword(s):  
New Zealand ◽  
High Risk ◽  
Succinate Dehydrogenase ◽  
Fungicide Resistance ◽  
Fungal Pathogens ◽  
Resistance Management ◽  
Resistance Development ◽  
Development Of Resistance ◽  
Action Committee ◽  
Succinate Dehydrogenase Inhibitor

Succinate dehydrogenase inhibitor (SDHI) fungicides are currently represented in New Zealand by eight active ingredients bixafen boscalid carboxin fluaxapyroxad fluopyram isopyrazam penthiopyrad and sedaxane They are either currently registered or undergoing development in New Zealand for use against a range of ascomycete and basiodiomycete pathogens in crops including cereals ryegrass seed apples pears grapes stonefruit cucurbits and kiwifruit These fungicides are considered to have medium to high risk of resistance development and resistance management is recommended by the Fungicide Resistance Action Committee (FRAC) in Europe Guidelines are presented for use of SDHI fungicides in New Zealand to help avoid or delay the development of resistance in the fungal pathogens that they target

scholarly journals Strategies to manage the evolution of glyphosate resistance in New Zealand

2016 ◽  
Vol 69 ◽  
pp. 252-257 ◽  
Author(s):  
K.C. Harrington ◽  
T.K. James ◽  
M.D. Parker ◽  
H. Ghanizadeh
Keyword(s):  
New Zealand ◽  
Weed Control ◽  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Lolium Multiflorum ◽  
Resistance Management ◽  
Glyphosate Resistance ◽  
Italian Ryegrass ◽  
Fruit Crops ◽  
Sustainable Farming

The first cases of weeds developing resistance to glyphosate within New Zealand have recently been reported and investigated Both perennial ryegrass (Lolium perenne) and Italian ryegrass (Lolium multiflorum) populations have become resistant to glyphosate in several Marlborough vineyards due to many years of weed control using mainly just glyphosate Glyphosate is currently being used in many situations throughout New Zealand that could easily lead to further resistance developing such as in other perennial fruit crops on roadsides railways amenity areas waste areas fence lines and headlands of crops Following wide consultation as part of a Sustainable Farming Fund project strategies for resistance management in three systems (vineyard and orchards amenity and waste areas and crops and pastures) are suggested Adoption of these strategies will allow glyphosate to continue as a useful herbicide in New Zealand

scholarly journals A volatile compound 2undecanone increases walking but not flying tomato potato psyllid movement toward an odour source

2014 ◽  
Vol 67 ◽  
pp. 184-190 ◽  
Author(s):  
M.M. Davidson ◽  
R.C. Butler ◽  
N.M. Taylor ◽  
M-C. Nielsen ◽  
C.E. Sansom ◽  
...  
Keyword(s):  
New Zealand ◽  
North America ◽  
Integrated Pest Management ◽  
Pest Management ◽  
Volatile Compound ◽  
Management Strategy ◽  
Potato Psyllid ◽  
Bactericera Cockerelli ◽  
Odour Source ◽  
Important Pest

Bactericera cockerelli (tomato potato psyllid; TPP) is an important pest of solanaceous crops in New Zealand and North America A volatile compound that alters the behaviour of TPP could be developed into a component of an integrated pest management strategy for solanaceous crops One compound 2undecanone was found to increase the percentages of female and male TPP (65 P

Sign in / Sign up

Export Citation Format

Share Document