Comparison of sampling procedures for estimating botrytis bunch rot incidence in New Zealand vineyards

Quantifying botrytis bunch rot (BBR) in vineyards is essential to the New Zealand wine industry Simple random sampling (SRS) inverse sampling (IS) and adaptive cluster sampling (ACS) were compared using simulated disease incidence at two levels (1 and 3) three clustering factors (random low and high) and small (100 bays) or large (2500 bays) vineyard sizes Sampling relative efficiency (re) was highest using ACS when disease was highly clustered at low incidence Inverse sampling was investigated by repeatedly sampling from the simulated vineyards which resulted in total sample number and variance of IS being greatest in highly clustered BBR at low incidence IS resulted in a lower final sample number with less variance than ACS using simulated BBR that was randomly dispersed at 3 IS or SRS using a sample size calculated from desired sample confidence can provide practical and accurate botrytis bunch rot sampling for disease management decision support

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Grape tendrils as an inoculum source of Botrytis cinerea in vineyards a review

New Zealand Plant Protection ◽

10.30843/nzpp.2012.65.5373 ◽

2012 ◽

Vol 65 ◽

pp. 218-227 ◽

Cited By ~ 5

Author(s):

D.C. Mundy ◽

R.H. Agnew ◽

P.N. Wood

Keyword(s):

New Zealand ◽

Botrytis Cinerea ◽

Wine Industry ◽

Inoculum Sources ◽

Inoculum Source ◽

Major Disease ◽

Wide Range ◽

Bunch Rot ◽

Considerable Damage

Botrytis cinerea is a fungus responsible for considerable damage to a wide range of crops worldwide including grapes Botrytis bunch rot caused by B cinerea is the major disease problem that must be managed by the New Zealand wine industry each season However the fungus is not easily managed as it can be both necrotrophic and saprophytic with a range of overwintering inoculum sources New Zealand grape growers have asked whether it is necessary to remove tendrils at the time of pruning in order to minimise botrytis bunch rot infection at harvest This review provides a summary of the information currently available on the importance of tendrils in the epidemiology of botrytis bunch rot under New Zealand conditions Gaps in knowledge and areas for further investigation are also identified

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Botrytis cinerea control on Sauvignon blanc using a recycling sprayer

New Zealand Plant Protection ◽

10.30843/nzpp.2012.65.5377 ◽

2012 ◽

Vol 65 ◽

pp. 249-255

Author(s):

V. Raw ◽

D.C. Mundy ◽

A.R.G McLachlan ◽

C. Clifford ◽

M. Walter

Keyword(s):

New Zealand ◽

Disease Control ◽

Botrytis Cinerea ◽

Wine Industry ◽

Target Area ◽

Economic Threshold ◽

Control Efficacy ◽

Sauvignon Blanc ◽

Bunch Rot ◽

Excellent Coverage

The New Zealand wine industry is strongly committed to sustainable production The SprayPro Rseries sprayer is designed to recycle unused chemical sprays not deposited on the target area Sauvignon blanc vines in Marlborough New Zealand were studied during 2011/2012 The vineyard area was 5 ha at 80 flowering where the full canopy was sprayed and 10 ha at pre bunch closure (PBC) targeting the fruiting zone only Disease control efficacy of spray recycling was investigated using Botrytis cinerea as the model pathogen Pathogen colonisation of necrotic leaf discs placed in the canopy at 80 flowering and PBC showed even control of B cinerea At PBC 80 of the watersensitive papers had adequate to excellent coverage Botrytis bunch rot incidence and severity were evenly expressed throughout the block but increased during preharvest; severity was well below the 3 economic threshold Recycling of botryticides did not affect disease control

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Mini munchers to control powdery mildew and botrytis bunch rot in grapes

New Zealand Plant Protection ◽

10.30843/nzpp.2010.63.6591 ◽

2010 ◽

Vol 63 ◽

pp. 279-279

Author(s):

K.S.H. Boyd-Wilson ◽

S. Read ◽

D.C. Mundy

Keyword(s):

New Zealand ◽

Disease Management ◽

Powdery Mildew ◽

Production Systems ◽

Growing Season ◽

Wine Industry ◽

Wine Production ◽

Apple Leaves ◽

Bunch Rot ◽

Organic Wine

The use of mycophagous (fungal feeding) invertebrates has potential to contribute to disease management in both organic and conventional wine production systems in New Zealand The New Zealand wine industry is actively working towards producing ultralow residue wines This involves removing all late season botrytis fungicide sprays from the vineyard spray programme In organic wine production systems in New Zealand the only products available to control powdery mildew and botrytis bunch rot are protectants In both these systems when fungicides are not available mycophagous invertebrates may reduce the amount of inoculum available to cause disease A survey of leaf material in 19 vineyards in Canterbury and Marlborough over the 20082009 growing season identified populations of beetles in two vineyards in sufficient numbers to justify further research In the laboratory fieldcollected beetles that were starved for 2 days fed on spores of Botrytis cinerea (botrytis bunch rot) growing on blackcurrant flowers Podosphaerea leucotricha (apple powdery mildew) on apple leaves and Erysiphe necator (grape powdery mildew) on grape leaves Beetles were identified as Aridius bifaciatus (Reitter) A nodifer (Westwood) and Cortinicara hirtalis (Broun)

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Susceptibility of New Zealand wheat cultivars to sharp eyespot

New Zealand Plant Protection ◽

10.30843/nzpp.2005.58.4292 ◽

2005 ◽

Vol 58 ◽

pp. 268-272 ◽

Cited By ~ 5

Author(s):

M.G. Cromey ◽

R.C. Butler ◽

C.A. Munro ◽

S.C. Shorter

Keyword(s):

New Zealand ◽

Disease Incidence ◽

Growing Season ◽

Field Trials ◽

Genetic Interactions ◽

Wheat Cultivars ◽

The Third ◽

Sharp Eyespot ◽

Low Levels ◽

Low Incidence

The susceptibility of 12 New Zealand wheat cultivars to sharp eyespot (caused by Rhizoctonia cerealis) was examined in three autumnsown field trials in the 200405 growing season Moderate to high disease incidence was recorded in two of the trials and low levels occurred in the third While disease incidence was high in at least some plots of most cultivars low incidence was recorded in all plots of two cultivars and all but two plots of two other cultivars These trials provide evidence that at least 2 of the 12 cultivars have useful levels of resistance to sharp eyespot and that several cultivars are highly susceptible Ranking of the more susceptible cultivars varied between locations Further work is required to determine whether this is due to genetic interactions between hosts and pathogens or whether relative susceptibility of cultivars to sharp eyespot can be affected by environment

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A comparison of soil sampling procedures used to monitor soil fertility in permanent pastures

Soil Research ◽

10.1071/sr9840081 ◽

1984 ◽

Vol 22 (1) ◽

pp. 81 ◽

Cited By ~ 16

Author(s):

DK Friesen ◽

GJ Blair

Keyword(s):

Sampling Method ◽

Nutrient Status ◽

Temporal Variations ◽

Cluster Sampling ◽

Soil Test ◽

Sampling Strategies ◽

Grazed Pasture ◽

The Mean ◽

Sampling Procedures ◽

Bray 1

Soil testing programs are often brought in disrepute by unexplained variability in the data. The deposition of dung and urine onto grazed pasture brings about marked variation in the chemical status of soils which contributes to this variability. A study was undertaken to compare a range of sampling procedures to estimate Colwell-P, Bray-1 P, bicarbonate K and pH levels in adjacent low and high P status paddocks. The sampling strategies used consisted of 75 by 50 m grids; whole and stratified paddock zig-zag and cluster (monitor plot) samplings. Soil test means for the various parameters did not vary among sampling methods. The number of grid samples required to estimate within 10% of the mean varied from 121 for Bray-1 P down to 1 for soil pH. Sampling efficiencies were higher for cluster sampling than for whole paddock zig-zag path sampling. Stratification generally did not improve sampling efficiency in these paddocks. Soil test means declined as sampling depth increased, but the coefficient of variation remained constant for Colwell-P and pH. The results indicate that cluster sampling (monitor plots) is the most appropriate procedure for estimating the nutrient status of grazed pastures. This sampling method enables a more accurate measure to be taken of the nutrient status of a paddock and should allow more reasonable estimates to be made of the temporal variations in soil test.

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Spatial Heterogeneity of the Incidence of Powdery Mildew on Hop Cones

Plant Disease ◽

10.1094/pd-90-1433 ◽

2006 ◽

Vol 90 (11) ◽

pp. 1433-1440 ◽

Cited By ~ 17

Author(s):

David H. Gent ◽

Walter F. Mahaffee ◽

William W. Turechek

Keyword(s):

Powdery Mildew ◽

Spatial Heterogeneity ◽

Power Law ◽

Binomial Distribution ◽

Disease Incidence ◽

Disease Assessment ◽

Cluster Sampling ◽

Data Sets ◽

Ratio Test ◽

Frequency Distributions

The spatial heterogeneity of the incidence of hop cones with powdery mildew (Podosphaera macularis) was characterized from transect surveys of 41 commercial hop yards in Oregon and Washington from 2000 to 2005. The proportion of sampled cones with powdery mildew ( p) was recorded for each of 221 transects, where N = 60 sampling units of n = 25 cones assessed in each transect according to a cluster sampling strategy. Disease incidence ranged from 0 to 0.92 among all yards and dates. The binomial and beta-binomial frequency distributions were fit to the N sampling units in a transect using maximum likelihood. The estimation procedure converged for 74% of the data sets where p > 0, and a loglikelihood ratio test indicated that the beta-binomial distribution provided a better fit to the data than the binomial distribution for 46% of the data sets, indicating an aggregated pattern of disease. Similarly, the C(α) test indicated that 54% could be described by the beta-binomial distribution. The heterogeneity parameter of the beta-binomial distribution, θ, a measure of variation among sampling units, ranged from 0.01 to 0.20, with a mean of 0.037 and a median of 0.015. Estimates of the index of dispersion ranged from 0.79 to 7.78, with a mean of 1.81 and a median of 1.37, and were significantly greater than 1 for 54% of the data sets. The binary power law provided an excellent fit to the data, with slope and intercept parameters significantly greater than 1, which indicated that heterogeneity varied systematically with the incidence of infected cones. A covariance analysis indicated that the geographic location (region) of the yards and the type of hop cultivar had little effect on heterogeneity; however, the year of sampling significantly influenced the intercept and slope parameters of the binary power law. Significant spatial autocorrelation was detected in only 11% of the data sets, with estimates of first-order autocorrelation, r1, ranging from -0.30 to 0.70, with a mean of 0.06 and a median of 0.04; however, correlation was detected in only 20 and 16% of the data sets by median and ordinary runs analysis, respectively. Together, these analyses suggest that the incidence of powdery mildew on cones was slightly aggregated among plants, but patterns of aggregation larger than the sampling unit were rare (20% or less of data sets). Knowledge of the heterogeneity of diseased cones was used to construct fixed sampling curves to precisely estimate the incidence of powdery mildew on cones at varying disease intensities. Use of the sampling curves developed in this research should help to improve sampling methods for disease assessment and management decisions.

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Defining Regions: the making of places in the New Zealand wine industry

Australian Geographer ◽

10.1080/00049182.2012.619956 ◽

2011 ◽

Vol 42 (4) ◽

pp. 419-433 ◽

Cited By ~ 13

Author(s):

Warwick E. Murray ◽

John Overton

Keyword(s):

New Zealand ◽

Wine Industry

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A systematic approach to evaluating and ranking the relative animal welfare impacts of wildlife control methods: poisons used for lethal control of brushtail possums (Trichosurus vulpecula) in New Zealand

Wildlife Research ◽

10.1071/wr16041 ◽

2016 ◽

Vol 43 (7) ◽

pp. 553 ◽

Cited By ~ 16

Author(s):

N. J. Beausoleil ◽

P. Fisher ◽

K. E. Littin ◽

B. Warburton ◽

D. J. Mellor ◽

...

Keyword(s):

New Zealand ◽

Animal Welfare ◽

Policy Development ◽

Management Decision ◽

Pest Species ◽

Control Methods ◽

Trichosurus Vulpecula ◽

Welfare Impacts ◽

Wildlife Control ◽

Management Decision Making

Context Control of unwanted wildlife (‘pest’ animals) is undertaken for conservation and economic reasons, and when such animals are considered a nuisance. Such control should be undertaken using approaches that minimise, as far as possible, detrimental impacts on the welfare of the animals. Using a scientific framework based on the Five Domains model, the relative welfare impacts of pest control methods can be compared across methods and pest species. Aims We demonstrate the application of a modified version of this framework to evaluate the relative impacts of seven Vertebrate Toxic Agents (VTAs) used to control brushtail possums (Trichosurus vulpecula) in New Zealand. The evaluation is used to produce a ranking of the seven VTAs based on their relative impacts on possum welfare. Methods Scientific literature describing mode of toxic action, specific effects in possums or other animals and reports from human poisonings was collated as reference material for a panel of six experts. The panel produced a median welfare impact score (‘none’ to ‘extreme’) for each of the Five Domains. The ‘Overall Grade’ (1 to 8) reflected the intensity and duration of all impacts of a VTA on possums. Key results All VTAs evaluated have at least moderate impacts on possum welfare, lasting for at least minutes. Cyanide was assessed as having the lowest welfare impacts (median grade 4), and cholecalciferol and the anticoagulants the highest impacts (7.5 to 8). Zinc phosphide was assigned an intermediate grade (6) with high confidence. While the overall impacts of sodium fluoroacetate (1080) and phosphorus were also assessed as intermediate (6), the panel’s confidence in these scores was low. Conclusions From an animal welfare perspective, anticoagulant poisons and cholecalciferol should be the least preferred options for controlling possums in New Zealand, as VTAs with less severe welfare impacts are available. Implications The results of such assessments allow animal welfare impacts to be integrated with other factors in wildlife management decision-making and policy development, and are thus useful for managers, researchers, regulators and operators. Evaluation of welfare impacts aligns with the goals and mandates of ethical wildlife control and may also be valuable in wider wildlife research and management activities.

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