Population dynamics of dicarboximide-resistant strains of Botrytis cinerea on grapevine in New Zealand

1990 ◽  
Vol 39 (3) ◽  
pp. 501-509 ◽  
Author(s):  
H. A. PAK ◽  
R. E. BEEVER ◽  
E. P. LARACY
2009 ◽  
Vol 62 ◽  
pp. 401-401 ◽  
Author(s):  
P.J. Wright ◽  
S. Chng ◽  
R.E. Beever ◽  
J. Thompson

Isolates from Botrytis cinerea collected from greenhouse tomato crops throughout New Zealand were tested for resistance to the dicarboximide fungicide vinclozolin and the benzimidazole fungicide carbendazim by assessing fungal growth on agar media amended with the fungicides (100 ppm active ingredient for both fungicides) Benzimidazole resistant strains of B cinerea were found on 15 of the 18 properties examined and dicarboximideresistant strains were found on 11 properties Dicarboximide resistance was more prevalent in the Auckland region with 71 of isolates resistant compared to 5 of isolates resistant for the other three regions All of the strains that were resistant to dicarboximide were also resistant to benzimidazole The high levels of dicarboximide resistant strains in the Auckland region correspond to reported loss of fungicide efficacy and loss of disease control in some greenhouses in this region


1995 ◽  
Vol 2 (1) ◽  
pp. 39 ◽  
Author(s):  
Doug P. Armstong ◽  
Ian G. McLean

One of the most common tools in New Zealand conservation is to translocate species to new locations. There have now been over 400 translocations done for conservation reasons, mainly involving terrestrial birds. Most translocations have been done strictly as management exercises, with little or no reference to theory. Nevertheless, translocations always involve some underlying theory, given that people must inevitably choose among a range of potential translocation strategies. We review theory relevant to translocations in the following areas: habitat requirements, susceptibility to predation, behavioural adaptation, population dynamics, genetics, metapopulation dynamics, and community ecology. For each area we review and evaluate the models that seem to underpin translocation strategies used in New Zealand. We report experiments testing some of these models, but note that theory underlying translocation strategies is largely untested despite a long history of translocations. We conclude by suggesting key areas for research, both theoretical and empirical. We particularly recommend that translocations be designed as experimental tests of hypotheses whenever possible.


PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243794
Author(s):  
Sam McKechnie ◽  
David Fletcher ◽  
Jamie Newman ◽  
Corey Bragg ◽  
Peter W. Dillingham ◽  
...  

A suite of factors may have contributed to declines in the tītī (sooty shearwater; Ardenna grisea) population in the New Zealand region since at least the 1960s. Recent estimation of the magnitude of most sources of non-natural mortality has presented the opportunity to quantitatively assess the relative importance of these factors. We fit a range of population dynamics models to a time-series of relative abundance data from 1976 until 2005, with the various sources of mortality being modelled at the appropriate part of the life-cycle. We present estimates of effects obtained from the best-fitting model and using model averaging. The best-fitting models explained much of the variation in the abundance index when survival and fecundity were linked to the Southern Oscillation Index, with strong decreases in adult survival, juvenile survival and fecundity being related to El Niño-Southern Oscillation (ENSO) events. Predation by introduced animals, harvesting by humans, and bycatch in fisheries also appear to have contributed to the population decline. It is envisioned that the best-fitting models will form the basis for quantitative assessments of competing management strategies. Our analysis suggests that sustainability of the New Zealand tītī population will be most influenced by climate, in particular by how climate change will affect the frequency and intensity of ENSO events in the future. Removal of the effects of both depredation by introduced predators and harvesting by humans is likely to have fewer benefits for the population than alleviating climate effects.


PLoS ONE ◽  
2014 ◽  
Vol 9 (11) ◽  
pp. e112846 ◽  
Author(s):  
Karlette A. Fernandes ◽  
Sandra Kittelmann ◽  
Christopher W. Rogers ◽  
Erica K. Gee ◽  
Charlotte F. Bolwell ◽  
...  

Author(s):  
S. M. Francis

Abstract A description is provided for Peronospora anemones. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Anemone coronaria, A. globosa. DISEASE: Downy mildew of anemones. Infected leaves lose their natural bloom, appearing dull green, almost grey in colour and are often down curled giving the plant a rounded appearance. As the disease progresses, leaf colour may change to shades of pink or purple with necrotic areas appearing on the older leaves. Invasion by secondary organisms (e.g. Botrytis cinerea) is common, especially after frost or storm injury, and this accelerates plant death. In favourable conditions conidiophores develop forming a whitish-grey down on the lower leaf surface, on the bracts and, less frequently, on the petioles. It is not uncommon for affected plants to show little or no sporulation and in these cases the presence of extensive intercellular mycelium and, later in the season, oospores in petioles and peduncles helps diagnosis. GEOGRAPHICAL DISTRIBUTION: Australasia (New Zealand); Europe (England, Jersey, France, Italy, Netherlands). TRANSMISSION: Primary infection is caused by oospores in plant debris in the soil. Tramier (1963) was unable to germinate oospores and thus work out precise details of the conditions affecting their germination but he showed evidence that regular and prolonged rain encouraged germination. Conidia, which cause secondary infections, are dispersed by rain and during harvesting of the flowers. Wind is thought to be unimportant in their dissemination as shown by glass slides covered with vaseline and placed near an infected crop (Tramier, 1965).


2019 ◽  
Vol 366 (8) ◽  
Author(s):  
Sophie Van Hamelsveld ◽  
Muyiwa E Adewale ◽  
Brigitta Kurenbach ◽  
William Godsoe ◽  
Jon S Harding ◽  
...  

Abstract Baseline studies are needed to identify environmental reservoirs of non-pathogenic but associating microbiota or pathogenic bacteria that are resistant to antibiotics and to inform safe use of freshwater ecosystems in urban and agricultural settings. Mesophilic bacteria and Escherichia coli were quantified and isolated from water and sediments of two rivers, one in an urban and one in an agricultural area near Christchurch, New Zealand. Resistance of E. coli to one or more of nine different antibiotics was determined. Additionally, selected strains were tested for conjugative transfer of resistances. Despite having similar concentrations of mesophilic bacteria and E. coli, the rivers differed in numbers of antibiotic-resistant E. coli isolates. Fully antibiotic-susceptible and -resistant strains coexist in the two freshwater ecosystems. This study was the first phase of antibiotic resistance profiling in an urban setting and an intensifying dairy agroecosystem. Antibiotic-resistant E. coli may pose different ingestion and contact risks than do susceptible E. coli. This difference cannot be seen in population counts alone. This is an important finding for human health assessments of freshwater systems, particularly where recreational uses occur downstream.


2001 ◽  
Vol 28 (1) ◽  
pp. 87 ◽  
Author(s):  
N. D. Barlow ◽  
G. L. Norbury

Introduced ferrets (Mustela furo) in New Zealand are subject to population control to reduce their threat to native fauna and the incidence of bovine tuberculosis (Tb) in livestock. To help in evaluating control options and to contribute to a multi-species model for Tb dynamics, a simple Ricker model was developed for ferret population dynamics in a semi-arid environment. The model was based on two data sets and suggested an intrinsic rate of increase for ferrets of 1.0–1.3 year–1 and a carrying capacity of 0.5–2.9 km–2. There was evidence for direct density-dependence in both data sets and the effect appeared to act mainly on recruitment. Dependence of the rate of increase of predators on the density of wild rabbits (Oryctolagus cuniculus) was exhibited in one of the two data sets, together with a numerical response relating current density of predators asymptotically to current density of rabbits, their primary prey. Predators in this data set included both cats and ferrets, estimated from spotlight counts, but the other data set demonstrated a direct proportionality between predator (cat and ferret) spotlight counts and minimum ferrets known to be alive by trapping. The model suggested, firstly, that populations are hard to suppress by continuous culling, with at least a 50% removal per year necessary to effect a suppression of 50% in long-term average density. Secondly, if control is episodic rather than continuous, culling in autumn gives a greater degree of suppression over time (280%, accumulated over time) than culling in spring (180%). A differential equation version of the model provides a component for a general Anderson/May bovine Tb/wildlife (possum/deer/ferret) model.


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