19366 research outputs found
Sort by
Identification of Leptosphaeria species causing stem canker and dry rot disease of Brassica species in New Zealand
No full textLeptosphaeria maculans and L. biglobosa are major pathogens of brassica crops, including canola (oilseed rape) and swede. Selection of canola cultivars with resistance genes to correspond with the avirulence genes of the local fungal population is an approach used overseas for controlling the disease. This study aimed to determine the main causal agent(s) in New Zealand, and, for a subset of 30 L. maculans isolates, the presence of 7 avirulence alleles (AvLm1, AvLm2, AvLm4, AvLm5, AvLm6, AvLm7, and AvLm11). The pathogenicity of these isolates on canola ‘Flash’ and swede ‘Highlander’ was also determined. Leptosphaeria maculans was the predominant species (n=127) recovered from leaf lesions, stem canker and dry rot tissue on canola, swede and turnip plants, with only 4 isolates identified as L. biglobosa recovered from stem cankers on canola, cauliflower and kale. All avirulence alleles were present in the New Zealand L. maculans population, with AvLm5 and AvLm6 amplified from all 30 isolates. The most common allele structure was avLm1-avLm2-avLm4-AvLm5-AvLm6- AvLm7-avLm11 (n=15, Avr refers to avirulence and avr refers to virulence allele) representing isolates recovered from canola, swede and turnip across New Zealand, followed by avLm1-avLm2-AvLm4- AvLm5-AvLm6-AvLm7-AvLm11 (n=7) only recovered from canola from Canterbury. L. maculans isolates were more pathogenic on swede ‘Highlander’ than canola ‘Flash’, forming more extensive stem cankers on swede after 65 days. There was no correlation between pathogenicity of the isolates and crop origin, or avirulence groupings observed. This study provides a base line evaluation of the avirulence allele frequencies in the New Zealand L. maculans population
A century of weed change in New Zealand’s forage seed multiplication industry
No full textInternational seed trading provides a significant introductory pathway for weed seeds, and many globally established weeds originated as contaminants in agricultural seed lots. Management of these trade systems helps minimize agricultural losses and is an important means of preventing future biological incursions. Forage crop seed lots could be considered higher risk than seed lots of arable and vegetable crops, as they have been found to have a higher percentage of contaminated seed lots. Two of the most commonly used temperate forage crops worldwide are perennial ryegrass (Lolium perenne) and white clover (Trifolium repens). New Zealand is one of the top producers of these crop seeds globally, and both species are commonly used in New Zealand pastures. Using historical and current seed lot analytical purity test results, we examined the frequency, identity and temporal changes of weed seeds found within agricultural seed lots of perennial ryegrass and white clover grown in New Zealand from 1912 to 2019. Overall, the percentage of contaminated forage seed lots decreased between approximately three to sixfold over the study period, indicating that herbicide availability, seed certification and improved crop management have been effective for weed control. However, we identified a handful of annual weed species that could become more problematic in the future, either because they showed an increasing presence trend in seed lots or were identified as the most common contaminants. In 2019, Vulpia bromoides was the most common contaminant in perennial ryegrass seed lots, and Chenopodium album was the most common in white clover seed lots. Sherardia arvensis and Poa annua, both significant species with an increasing presence trend, had the largest increases in perennial ryegrass seed lots over the study period. Conversely, Rumex acetosella had the largest presence decline for both crop species. There was a significant difference between the percentage of contaminant species that were grass weeds between study crops, where perennial ryegrass seed lots had approximately four times more grass species than white clover. Considering New Zealand trades crop seed with approximately half of the world’s countries and contributes substantially to the global supply of for-age seed, our study provides a unique insight into changes of the weed spectrum throughout the seed for sowing system over the last century
Understanding the dynamics of psychological ownership and community embeddedness in family businesses: A case study Barker’s of Geraldine
No full textFamily businesses are crucial in rural communities primarily due to their strong community embeddedness. However, existing literature lacks an in-depth understanding of the motivations and drivers behind this community embeddedness. This study explored the interconnections between psychological ownership, community embeddedness, and family businesses in rural communities and examined their practical implications. This study fills this gap by conducting an exploratory case study of Barker's of Geraldine, contributing to the literature by highlighting psychological ownership as a key motivation and driver for community embeddedness in family businesses. This research provides practical insights that guide policy and economic development initiatives in rural areas by investigating the link between psychological ownership and community embeddedness in rural family businesses
Wine aromas
No full textWine has a complex matrix with many volatile compounds present, which evolves over time. These volatile compounds are important to wine quality as they contribute to the aroma and varietal characteristics of wine. Recent development in the analysis of volatile compounds in wine has greatly improved our understanding of the complexity of wine aroma. Analytical methods used for wine aroma fingerprinting have shown potential in determining the origin and quality of wine. Thus, research on volatile compounds responsible for wine aroma and their correlation with wine provenance and wine quality have increasingly attracted great interest from researchers and winegrowers. This Special Issue presents the latest research regarding wine aroma compounds, including, but not limited to, the topics on the characterization of aroma compounds in grapes and wine, factors influencing the production of aroma compounds in wine during fermentation and maturation, and analytical methods for wine aroma analysis
Wise Response Society Inc. Hearing oral submission on coastal environment of the proposed Regional Policy Statement
No full textScope of Oral Submission
1. The points we wish to highlight in this Oral submission link to two key questions
• What is the best approach and best settings in the coastal environment anticipating a low carbon economy?
• How does the RPS best integrate those with other planning instruments and provisions (including Tangata Whenua opportunity)
Improving the performance of FVCs for economic development, food and nutritional security
No full textImproving the performance of agri-food value chains for economic development and food and nutrition security is vital amid emerging local and global challenges. Literature confers severe underinvestment throughout fruit value chains in emerging economies, resulting in high post-harvest losses, leading to a persistent shortfall in the availability of affordable fruit, and eroding actors' margins. The primary aim of this study was to identify the causes of the poor performance of the avocado value chain in Ethiopia and simulate the impacts of a select set of coherent interventions. System dynamics modelling was adopted for its system-wide view, ability to handle complexity, dynamics and multiple objectives and measure quantitative ex-ante impacts. The research aim was achieved through an extensive literature review, direct observation of all chain activities, in-depth semi-structured interviews, and participatory model-building workshops to collect data, build qualitative and quantitative models, select interventions and validate outputs. Secondary data from various sources complemented primary data from participants.
Qualitative modelling identified several feedback loops representing a vicious cycle in which underinvestments lead to remarkably high post-harvest losses, reducing fruit availability and affordability, impacting demand and discouraging investment. The high post-harvest loss reduces incomes, leading to low economic development and discouraging investment. The quantitative model simulation confirmed the continuing poor performance where producers cultivate a handful of less productive trees under a low-input production system, diminishing growth in availability. While significantly reducing availability, salient costs of the high post-harvest loss continue to erode margins in distant urban centres, even after continually pushing consumer prices up, reducing affordability.
Scenario analysis suggests current trajectory would lead to a worsening of performance even in a plausible best case, while interventions bring about robust positive ex-ante impacts on the availability, incomes and overall affordability from improved investment. Modernised and organised retailers can assume chain leadership and deploy bestowed customer value and market information to incentivise and sanction other transformed actors to invest, access and fulfil supply contracts, enforcing implemented quality and fruit handling standards and facilitating the flourishment of agribusiness credit services and efficient payment systems. The research identified institution changes essential to enhance the implementation and effectiveness of interventions. The research results contribute to designing interventions and augmenting the literature on upgrading, measuring performance and ex-ante impacts
Nematodes: Control tools
No full textThis note summarises the Disease and Product analysis prepared by a DISCONTOOLS group of experts on Nematodes. They reviewed the current knowledge of the disease, considered the existing disease control tools, identified current gaps in the availability and quality of the control tools and finally determined the research necessary to develop new or improved tools. Full details are available on the website at http://www.discontools.eu
Recurring summer and winter droughts from 4.2-3.97 thousand years ago in north India
No full textThe 4.2-kiloyear event has been described as a global megadrought that transformed multiple Bronze Age complex societies, including the Indus Civilization, located in a sensitive transition zone with a bimodal (summer and winter) rainfall regime. Here we reconstruct changes in summer and winter rainfall from trace elements and oxygen, carbon, and calcium isotopes of a speleothem from Dharamjali Cave in the Himalaya spanning 4.2–3.1 thousand years ago. We find a 230-year period of increased summer and winter drought frequency between 4.2 and 3.97 thousand years ago, with multi-decadal aridity events centered on 4.19, 4.11, and 4.02 thousand years ago. The sub-annually resolved record puts seasonal variability on a human decision-making timescale, and shows that repeated intensely dry periods spanned multiple generations. The record highlights the deficits in winter and summer rainfall during the urban phase of the Indus Civilization, which prompted adaptation through flexible, self-reliant, and drought-resistant agricultural strategies
How can multicultural communities be engaged effectively in the process of setting long-term visions for freshwater? : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Water Resource Management at Lincoln University
No full textThe National Policy Statement for Freshwater Management 2020 (NPS-FM) introduced Te Mana o te Wai (loosely translated as the vital importance of water), which requires councils to engage with communities and tangata whenua in any decision-making processes relating to water. It is important for local authorities such as Environment Canterbury (ECan) to engage with a diversity of cultures. According to census data, people of Asian ethnicity make up about 15% of the total New Zealand population, of which the ethnic Chinese group makes up the largest proportion. Previous research indicates that ethnic Chinese people in Christchurch are willing to be involved in environmental planning, but that there are barriers to their participation, such as lack of local environmental and political knowledge. This study aims to: (1) explore the meaning of Te Mana o te Wai to ethnic Chinese living in Christchurch; (2) identify and evaluate effective ways of engaging with ethnic Chinese in developing long-term visions for freshwater management; and (3) review existing documents for best-practice engagement with the ethnic Chinese group. Data was collected during July and August 2022. The researcher collected 151 anonymous survey responses (67 responses from the in-person approach and 84 responses collected online through social media channels). Ten semi-structured interviews were also conducted, comprising five participants from central and local government and five local Chinese community leaders. This study’s findings suggest that most Chinese had not heard of Te Mana o te Wai, but that most wanted to participate in decision-making processes around environmental planning or water management. This study highlights some barriers not previously identified in research, such as cultural differences and lack of capability and capacity for local authorities. The study concludes with recommendations to help the regional council improve ethnic Chinese participation in decision-making processes in order to achieve more inclusivity and collaboration with diverse ethnic groups in New Zealand
The interactions of iron nutrition, salinity and ultraviolet-B radiation on the physiological responses of wheat (Triticum aestivum L.)
No full textIncreasing human population, land degradation and global change is intensifying pressure on agricultural production in marginal environments. Many marginal environments experience multiple stressors, however, few studies have investigated the interaction of more than two stressors. This is the first study examining the interaction of Fe nutrition, salinity and ultraviolet-B (UV-B) radiation in plants. Wheat (Triticum aestivum L. cv. 1862) was grown in a three-way factorial design: iron (75 µM Fe and 3.75 µM Fe as FeCl₃), salinity (0 mM and 75 mM NaCl) and UV-B radiation (1 kJ m¯² d¯¹, and 15 kJ m¯² d¯¹ biologically effective UV-B) in chelator-buffered solutions. Examination of the stress interactions showed that phytosiderophore release and root Fe accumulation were limited by UV-B and NaCl stress under Fe deficiency. The findings demonstrated Fe dependency of plant responses to salinity and to UV-B, e.g. sufficient Fe is required for UV-B-induced stomatal opening. Other interactions included that elevated salinity alleviated Fe deficiency-induced decreases in water use efficiency. In addition, Fe deficiency increased the accumulation of UV-absorbing compounds under elevated UV-B radiation. UV-B radiation affected belowground morphology and physiology, including a 47 % reduction in phytosiderophore release. This is the first study to demonstrate a role for wavelengths other than photosynthetically active radiation in phytosiderophore release. Our findings demonstrate that aboveground environmental factors such as UV-B radiation can affect important aspects of belowground plant function, and that Fe availability needs to be considered when growing plants in saline or high UV-B radiation environments