Evaluation of fungicide efficacy against Neofusicoccum species causing dieback disease of blueberries in New Zealand

New Zealand pipfruit crops require postharvest fungicides for control of European canker caused by Neonectria ditissima Fungicide efficacy trials to protect leaf scars from N ditissima infections were conducted during autumn 2013 and 2014 Disease control of artificially inoculated leaf scars was achieved by single applications of copper oxychloride and copper oxide but not copper hydroxide applied at 43 11 and 06 kg elemental copper/ ha respectively Control of leaf scar infections by copper oxide (065 and 095 kg elemental copper/ha) was similar to control by captan Leaf scars (010 days old) remained susceptible to infections up to 10 days after leaf fall; disease control was achieved by redistribution of copper and captan fungicides onto new leaf scars Disease control using copper oxide was consistent and similar to control using captan The copper product and concentration of elemental copper are important for successful control of leaf scar infections by N ditissima

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

FEMS Microbes ◽

10.1093/femsmc/xtab016 ◽

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.

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

10.1101/2021.03.10.434845 ◽

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.

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Magellanic Cloud Eclipsing Binaries: Primary Distance Indicators

Symposium - International Astronomical Union ◽

10.1017/s007418090011900x ◽

1999 ◽

Vol 190 ◽

pp. 563-566

Author(s):

J. D. Pritchard ◽

W. Tobin ◽

J. V. Clausen ◽

E. F. Guinan ◽

E. L. Fitzpatrick ◽

...

Keyword(s):

New Zealand ◽

Magellanic Cloud ◽

Eclipsing Binaries ◽

Fundamental Parameters ◽

Distance Indicators

Our collaboration involves groups in Denmark, the U.S.A. Spain and of course New Zealand. Combining ground-based and satellite (IUEandHST) observations we aim to determine accurate and precise stellar fundamental parameters for the components of Magellanic Cloud Eclipsing Binaries as well as the distances to these systems and hence the parent galaxies themselves. This poster presents our latest progress.

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Heat-Etching with a Bullivant Type II Simple Freeze-Cleave Device

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067522 ◽

1970 ◽

Vol 28 ◽

pp. 106-107 ◽

Cited By ~ 1

Author(s):

Ronald S. Weinstein ◽

N. Scott McNutt

Keyword(s):

New Zealand ◽

General Hospital ◽

Massachusetts General Hospital ◽

Type I ◽

Type Ii ◽

Collaborative Effort ◽

Temperature And Pressure ◽

The University

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.

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A Cytochemical Study of Glucose-6-Phosphatase (G-6-PASE) in Cells Participating in Atherogenesis of Rabbit Aorta

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115924 ◽

1975 ◽

Vol 33 ◽

pp. 460-461

Author(s):

Sidney D. Kobernick ◽

Edna A. Elfont ◽

Neddra L. Brooks

Keyword(s):

Lipid Metabolism ◽

New Zealand ◽

Aortic Wall ◽

Rabbit Aorta ◽

Plaque Formation ◽

Metabolic Changes ◽

Atherosclerotic Plaques ◽

Cytochemical Study ◽

Cellular Alteration ◽

New Zealand White Rabbits

This cytochemical study was designed to investigate early metabolic changes in the aortic wall that might lead to or accompany development of atherosclerotic plaques in rabbits. The hypothesis that the primary cellular alteration leading to plaque formation might be due to changes in either carbohydrate or lipid metabolism led to histochemical studies that showed elevation of G-6-Pase in atherosclerotic plaques of rabbit aorta. This observation initiated the present investigation to determine how early in plaque formation and in which cells this change could be observed.Male New Zealand white rabbits of approximately 2000 kg consumed normal diets or diets containing 0.25 or 1.0 gm of cholesterol per day for 10, 50 and 90 days. Aortas were injected jin situ with glutaraldehyde fixative and dissected out. The plaques were identified, isolated, minced and fixed for not more than 10 minutes. Incubation and postfixation proceeded as described by Leskes and co-workers.

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