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Stuart Fraser Mireia Gomez‐Gallego Judy Gardner Lindsay S. Bulman Sandra Denman Nari M. Williams 《Forest Pathology》2020,50(2)
Phytophthora pluvialis and Phytophthora kernoviae are the causal agents of important needle diseases on Pinus radiata in New Zealand. Little is known about the epidemiology of the diseases, making the development of control strategies challenging. To investigate the seasonality and climatic drivers of sporulation, inoculum traps, consisting of pine fascicles floating on water in plastic containers, were exchanged fortnightly at five sites in P. radiata plantations between February 2012 and December 2014. Sections of needle baits were plated onto selective media and growth of Phytophthora pluvialis and P. kernoviae recorded. To explore the generalizability of these data, they were compared to detection data for both pathogens from the New Zealand Forest Health Database (NZFHDB). Further, equivalent analyses on infection of Rhododendron ponticum by P. kernoviae in Cornwall, UK allowed the comparison of the epidemiology of P. kernoviae across different host systems and environments. In New Zealand, inoculum of P. pluvialis and P. kernoviae was detected between January–December and March–November, respectively. Inoculum of both species peaked in abundance in late winter. The probability of detecting P. pluvialis and P. kernoviae was greater at lower temperatures, while the probability of detecting P. pluvialis also increased during periods of wet weather. Similar patterns were observed in NZFHDB data. However, the seasonal pattern of infection by P. kernoviae in the UK was the opposite of that seen for sporulation in New Zealand. Phytophthora kernoviae was likely limited by warmer and drier summers in New Zealand, but by colder winter weather in the UK. These results emphasize the importance of considering both environmental drivers and thresholds in improving our understanding of pathogen epidemiology. 相似文献
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Four sets of durum samples were used in this study to further understand the interrelationships among hard vitreous kernels (HVK), protein content, and pigment concentration, with a focus on the interaction and synergistic effects of protein content and vitreousness on durum quality. HVK level increases with higher protein content in the range of 9.5–12.5%, but this relationship is less evident in durum samples with high protein content (12.5–14.5%). Both protein content and kernel vitreousness can significantly affect durum milling quality. White starchy kernels (WSK) in low protein durum have a very detrimental impact on milling and pasta processing quality, but high protein content can mitigate the adverse impact of WSK on durum quality. Although protein content plays a dominant role, higher HVK might contribute positively to pasta firmness. There was no significant difference in yellow pigment content between HVK and WSK. However, pigment loss from semolina to dough was higher for WSK than HVK. Despite the difference in protein content, HVK and WSK have little difference in gluten strength. The monomeric protein was preferentially accumulated in HVK. The glutenin proteins of HVK and WSK were similar in the ratios of 1Bx/1By and HMW/LMW-GS. 相似文献
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在农业生产中由于化学农药的长期不合理使用,导致"3R"问题持续存在和人类赖以生存的环境日益恶化,生物防治产品及技术在有害生物综合治理中的作用越发重要。天敌昆虫的生长发育及存活期往往很短,探索其储存技术是天敌昆虫规模化生产中的关键性环节。低温贮藏可以延长天敌昆虫的寿命,进而可以为生物防治提供充足、稳定的天敌产品。因此,天敌昆虫低温贮藏一直是生物防治领域研究的热点。本文围绕天敌昆虫低温贮藏这一环节,就低温诱导天敌昆虫滞育虫态、冷驯化对昆虫低温贮藏效果的影响、低温贮藏对天敌昆虫适合度(寿命、羽化率、性比、个体尺寸大小、飞行扩散能力等)的影响等方面进行综述,以期为天敌昆虫产品的规模化生产及应用技术提供参考。 相似文献
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Soil protection for a sustainable future: options for a soil monitoring network for Ireland 下载免费PDF全文
The increased recognition of the importance of soil is reflected in the UN Post‐2015 Development Agenda with sustainable development goals that directly and indirectly relate to soil quality and protection. Despite a lack of legally binding legislation for soil protection, the European Commission remains committed to the objective of soil protection. However, the achievement of a legally binding framework for soil protection relies on the implementation of a soil monitoring network (SMN) that can detect changes to soil quality over time. As beneficiaries do not pay for the provision of soil information, the options for soil monitoring are limited. The use of existing data sets should be considered first. Using Ireland as an example, this research explored the opportunities for a SMN for Ireland considering three existing national data sets. The options for a SMN are considered in terms of their spatial and stratified distribution, the parameters to be measured and an economic analysis of the options proposed. This research finds that for Ireland, either a 10 or a 16 km2 grid interval stratified by land use and drainage class offers the best potential in relation to the spatial distribution of existing data sets to reflect local data at a national level. With existing data, the stratified SIS data using the 16 km2 grid offers the best value for money, with baseline costs for analysis, excluding field costs, of between €706 481 and €2.8 million. Acknowledging the impossibility of measuring all parameters with ideal frequency, this study proposes a two‐tier system for optimized monitoring frequency. Parameters must anticipate future policy requirements. Finally, the implementation of a SMN must be accompanied by standardized methods, defined thresholds and action mandates to maintain soil quality within allowable limits. 相似文献
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在查清天津市园林主要花灌木刺吸口器害虫桃粉蚜、绣线菊蚜、棉蚜和山楂红蜘蛛发生消长规律的基础上 ,确定了防治适期和结合点 ,筛选出 10 %吡虫啉、绿灵、蚧螨灵、 1. 8%齐螨素和花保5种低、无毒药剂 ,防效均达到 90 %以上。查出天敌 13种 ,并对优势种作了取食量调查 相似文献
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