A5077679227- Biological Control of Invasive Species
- Weed Control and Herbicide Applications
- Ecology and Vegetation Dynamics Studies
- Plant pathogens and resistance mechanisms
- Agronomic Practices and Intercropping Systems
- Plant and fungal interactions
- Allelopathy and phytotoxic interactions
- Plant Pathogens and Fungal Diseases
- Plant Parasitism and Resistance
- Forest Insect Ecology and Management
- Ruminant Nutrition and Digestive Physiology
- Botany and Plant Ecology Studies
- Botany, Ecology, and Taxonomy Studies
- Turfgrass Adaptation and Management
- Nematode management and characterization studies
- Plant and animal studies
- Animal Ecology and Behavior Studies
- Plant responses to water stress
- Species Distribution and Climate Change
- Plant Disease Management Techniques
- Rangeland and Wildlife Management
- Horticultural and Viticultural Research
- Botanical Research and Chemistry
- Flowering Plant Growth and Cultivation
- Entomopathogenic Microorganisms in Pest Control
AgResearch
2015-2025
Lincoln University
1982-2000
Weeds can be major environmental and economic burdens in New Zealand. Traditional methods of weed control including manual chemical approaches time consuming costly. Some herbicides may have negative human health impacts. One the proposed important steps for providing alternatives to these traditional is automated identification mapping weeds. We used hyperspectral imaging data machine learning explore possibility fast, accurate discrimination weeds pastures where ryegrass clovers are sown...
Nassella neesiana (Chilean needle grass) reduces farm profitability through its sharp seeds that damage wool, skins, hides and carcasses. It poses a biosecurity risk in New Zealand's Hawke's Bay region due to seed dispersal via gravel crushed aggregate from braided rivers. This study evaluated flotation sieving remove both dry imbibed panicle seeds. We measured their length, width, mass, flotation, passage sieves with without the awn (a hygroscopic, bristle-like structure). The awned were,...
Abstract Currently there are some 187 plant species, almost all exotic in origin, occurring as "weeds" pastures New Zealand. Judging from their occurrence scientific papers published the proceedings of Zealand Plant Protection Society, 65 these species are, or have been considered historically, to be significant pastoral weeds. While 34 weeds currently being managed under Regional Pest Management Strategies, 15 regionally apparently un‐researched Zealand, implying that management does not a...
Summary 1. The extent to which the weed Cirsium arvense (creeping thistle) may be controlled by manipulating interspecific competition and herbivory was examined in two factorial experiments order identify non‐chemical herbicide‐based control methods for weed. 2. In first experiment, a single spring cultivation of grassland intensively grazed rabbits led 25‐fold increase C. cover within 3 months, effects were still present following summer. As well as destroying competing perennial...
Weeds are among the most damaging pests of agriculture, causing ≈10% worldwide reduction in crop productivity each year. Over-reliance on synthetic chemical herbicides has caused weeds around world to evolve resistance. Bioherbicides may be an alternative. However, their many constraints including strict environmental requirements, complicated mass-production and high product costs, limited pathogenicity a narrow spectrum activity frequently encountered major barriers commercialization.We...
Here we review published research on the costs of weeds to New Zealand's pastoral, arable and forestry sectors, propose an alternative dynamic approach for future research. The studies reviewed had little in common methodologically, often contained guesswork, or were outdated. Their aggregation resulted a conservative estimate cost agricultural economy $1658 million (2014 NZD). To address deficiencies previously used methodologies, is developed applied case study giant buttercup dairy...
Summary A field experiment was conducted from October 1992 to March 1997 in a sheep‐grazed pasture Canterbury, New Zealand, determine the effects of fungus Sclerotinia sclerotiorum on long‐term dynamics population Cirsium arvense . The pathogen applied mid‐spring either once or three consecutive years when C. shoots were vegetative rosettes, using granular, mycelium‐on‐wheat preparation that lodged leaves, stems and leaf axils. single application caused disease confined year. resulted...
Summary: In seven field experiments in which the effect of MCPA on Ranunculus acris subsp. dairy pastures New Zealand was studied, control varied between sites from 93% to 11% reduction ground cover. To determine if populations resistance MCPA, seedling progeny were sprayed with a range doses glasshouse. The LD 50 values ranged 0.36 kg ha −1 1.5 confirming existence genetic variability populations. Correlations and field, suggested that differences contributed control. A correlation...
Abstract Invasive plants can cause significant problems in natural and agricultural ecosystems. Although research has already been conducted on the economics of a single‐control option for some invasive weeds, we extended analysis by developing dynamic optimisation model that evaluates net benefits range possible control options simultaneously order to identify optimal strategy (mix options). This paper focuses Californian thistle (Cirsium arvense) pasture New Zealand. The benefit is...
S ummary Growth analysis was used to assess the response of vegetative rosettes Achillea millefolium L. (yarrow) shading in range full daylight irradiance a relative level (r.l.i.) 0–064. As functions time, SLA, LWR, NAR and RGR showed more or less pronounced ontogenetic drifts which interacted with r.l.i. total dry weight, these interactions were greatly diminished. At weights from 1.53 4.0 g, characterized by plateau between approx. 0.40 owing increases SLA LWR compensating for reduction...
Abstract Fungi and bacteria on the external surfaces of four gorse‐associated insect species: gorse seed weevil Apion ulicis Förster (Coleoptera: Apionidae), light brown apple moth Epiphyas postvittana Walker (Lepidoptera: Tortricidae), pod Cydia ulicetana Denis Schiffermüller Tortricidae) thrips Sericothrips staphylinus Haliday (Thysanoptera: Thripidae), were recovered by washing plating techniques. The isolates identified morphology polymerase chain reaction (PCR) restriction fragment...
We used the process-oriented niche model CLIMEX to estimate potential global distribution of serrated tussock under projected future climates. Serrated is a drought-tolerant, wind- and human-dispersed grass South American origin that has invaded pastures in Australia, Europe, New Zealand, Africa. The likely effect climate change on its was assessed by applying six climate-change scenarios previously developed model. projections climatic suitability current revealed considerable scope for...
Herbicide resistance has repeatedly developed under intensive herbicidal weed management regimes globally with 255 species having resistant biotypes. In New Zealand, since 1979, was found in 13 taxa, >25 herbicides 8 chemical classes showing reduced effectiveness (i.e. HRAC groups A, B, C, D, F, G, H, N and O). Cases included weeds turf, pastures, orchards, vineyards, forage arable crops. Surprisingly little is known about the spatial extent or frequency of this problem Zealand. We estimate...
Pastures represent about half of the global agricultural area and productivity losses from weeds are significant. The complex interactions between them other pasture plants, livestock environment imply a need for innovative research that transforms management. To this end, horizon scan was conducted to identify relevant issues, questions, opportunities, drivers. drivers were ranked using three criteria: (1) is (is driver likely become important in 10–20 years?); (2) will require stretchy...
Natural levels of Sclerotinia sclerotiorum ascsospores in the Canterbury region were determined over 3 years by trapping depositing ascospores dishes containing a selective agar. Mean 'horticulture', 'biocontrol-pasture', 'mixed cropping' and 'pasture' strata 115, 56, 10 m -2 day -1 , respectively. Ascospore deposition downwind small experimental biocontrol sites was measured on 2 days 1994 9 1997 late spring. Exponential depletion models scaled up to represent 1 ha site, revealed that...
1. Experiments were conducted (i) to determine whether resistance MCPA would subside in a population of Ranunculus acris L. ssp. after ending 30-year regime annual and biennial applications MCPA, (ii) test the hypothesis that MCPA-resistant R. plants are less competitive than MCPA-susceptible when grown together. 2. Experiment 1 was dairy pasture had developed repeated exposure this herbicide over period 30 years. Application either stopped or continued on plots for five consecutive growing...
Summary The regenerative response of the rhizomes Achillea millefolium L. to fragmentation and burial was studied in field experiments on three different soils. percentage buds producing shoots (estimated from surviving rhizome fragments) 4 cm (1·6 nodes), 8 (3·8 nodes) 16 (6·7 fragments 63, 44 32 respectively averaged over all soils depths 5, 10 15 cm. depth at which 50% failed produce an emerged shoot (LD 50 depth) 9·3, 12·4 17·9 for 4‐, 8‐ 16‐cm No survived soil surface. time emergence...