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61.
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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64.
Ting Shi Yan-Yan Yu Jia-Jia Dai Yi-Ting Zhang Wen-Peng Hu Li Zheng Da-Yong Shi 《Marine drugs》2021,19(3)
The species Pseudogymnoascus is known as a psychrophilic pathogenic fungus with a ubiquitous distribution in Antarctica. Meanwhile, the study of its secondary metabolites is infrequent. Systematic research of the metabolites of the fungus Pseudogymnoascus sp. HSX2#-11, guided by the method of molecular networking, led to the isolation of one novel polyketide, pseudophenone A (1), along with six known analogs (2–7). The structure of the new compound was elucidated by extensive spectroscopic investigation and single-crystal X-ray diffraction. Pseudophenone A (1) is a dimer of diphenyl ketone and diphenyl ether, and there is only one analog of 1 to the best of our knowledge. Compounds 1 and 2 exhibited antibacterial activities against a panel of strains. This is the first time to use molecular networking to study the metabolic profiles of Antarctica fungi. 相似文献
65.
The recent change in the regional development strategy of the European Union (EU) results in an important need to study the terms of change and their respective implications. This study seeks, through a bibliometric analysis, to ascertain the developments taking place in studies on research and innovation strategies for smart specialisation (RIS3) to identify shortcomings and opportunities for future research. This bibliometric review drew upon the Scopus database with the sample selected containing all the articles containing the keywords “Research and Innovation Strategies for Smart Specialisation” or “RIS3.” This correspondingly reports how some authors maintain that the path the EU should take involves imitative innovation. Meanwhile, others propose that each region should specialise in those industries that are already established there and thus avoid targeting any areas they do not already know/specialise in. Our findings detail six clusters in RIS3 research, which help in contextualising the literature review: (a) business discovery; (b) smart specialisation; (c) innovation; (d) specialisation; (e) regional policies; and (f) regional development. This study furthermore sets out perspectives for future lines of research and correspondingly seeks to convey a vast theoretical basis that may serve as the point of departure for future studies. 相似文献
66.
Climate change has become a global issue influencing human survival and development while low‐carbon is the inevitable choice. As the world’s largest emitter of greenhouse gases, China has become an important force that influences the cooperation of climate change. China is a large agricultural country, and the rural carbon emissions have been gradually increasing. We consider rural neighborhood as an important space for the use of low‐carbon ideas to address climate change. There is no specific assessment system for a rural neighborhood. The studies of rural neighborhood low‐carbon mainly focus on the method of calculation carbon emissions. However, only quantifying rural carbon emissions is insufficient. In this paper, a low‐carbon evaluation indicator system has been proposed for rural neighborhood and Fuzzy Comprehensive Evaluation has been applied to get the low‐carbon degree. Considering the influence and feedback inside the indicator system, Analytic Network Process was applied to get the weights. Furthermore, a case study was carried out for the using of the proposed method in an eco‐village of China. Our practice has proved that the system is easy to operate in rural neighborhood. 相似文献
67.
This paper examines the relationship between external knowledge sourcing and a diverse set of innovation outcomes in rural and urban establishments in the U.S. Existing studies in the broader knowledge management literature principally examine firms in a single industry, overwhelmingly rely on patent data to proxy for innovation, and cannot account for the innovations of businesses in rural American markets. By addressing these limitations using data from the 2014 Rural Establishment Innovation Survey of the USDA's Economic Research Service, this research provides novel insights into how externally acquired knowledge by American establishments may support innovation. Results of the analysis suggest that external knowledge sourcing may specifically promote product, process, and green innovation in U.S. firms. While collective results when external sources of information are divided by industry orientation fail to show that sources outside of a firm's industry play a dominant role in the innovation processes of American establishments in general, findings provide evidence for an outsized impact of these relationships within rural establishments specifically and suggest that external knowledge sourcing from extra‐industry organizations is most critical for promoting successful innovation in rural firms. Results additionally indicate that knowledge sourcing from non‐local organizations may be more important for supporting innovation in rural compared to urban markets. 相似文献
68.
Samuel K. Mutiga Nelson Chepkwony Owens A. Hoekenga Sherry A. Flint‐Garcia Rebecca J. Nelson 《Plant Breeding》2019,138(1):38-50
A kernel screening assay (KSA) was used to assess the genetic and environmental effects on the vulnerability of maize to aflatoxin accumulation. Kernels of 26 inbred lines that had been grown in seven environments, and 190 lines of the Intermated B73xMo17 (IBM) population grown in one location in the United States, were inoculated with a toxigenic strain of A. flavus and incubated in the dark at 30°C for 6 days. Percent kernel colonization (PKC), sporulation and aflatoxin were influenced by the maize genotypes (G), the location (“ear environment” or E) and the GxE interactions. Overall, low broad‐sense heritabilities were observed for PKC, sporulation and aflatoxin. PKC was significantly correlated with sporulation in all environments. Aflatoxin was positively correlated with colonization for two and with sporulation for all ear environments. Higher grain sulphur or magnesium in IBM was associated with less colonization or aflatoxin. Postharvest susceptibility of maize to aflatoxin is thus influenced by factors that are modulated by the ear environment. In a KSA, sporulation could be a proxy test for aflatoxin accumulation. 相似文献
69.
Esdras M. Carbajal M. Carolina Zuleta Luellen Swayzer Brian M. Schwartz Maria Carolina Chavarro A. Carolina Ballen‐Taborda Susana R. Milla‐Lewis 《Plant Breeding》2019,138(6):958-966
St. Augustinegrass is well suited for lawns and commercial landscapes. While many genotypes are cross‐fertile, all cultivars are propagated vegetatively in sod production. To ensure varietal purity, development of sterile triploid hybrids by crossing tetraploid and diploid genotypes has been successfully used in other warm‐season turfgrasses. Applying this model in St. Augustinegrass would be beneficial to sod producers and turf managers who require purity for certification and uniformity for performance, respectively. This study was conducted to develop colchicine‐induced tetraploid lines of St. Augustinegrass. Seeds of cultivar ‘Raleigh’ were treated with four colchicine concentrations at four exposure times. A non‐treated control was included among the treatments. Seedlings that germinated were screened for genome size changes using flow cytometry. Line DSA 13005 and two progeny lines derived through selfing, DSA 16001 and DSA 16016, were corroborated as tetraploids (2n = 4x = 36) through chromosome counts. These lines will be used in future breeding efforts to attempt development of sterile triploid cultivars of St. Augustinegrass. 相似文献
70.
以茶树品种‘龙井43’作为材料,利用RT-PCR方法,从茶树的cDNA中克隆得到1个编码蛋白激酶的基因,命名为CsCIPK。序列分析表明,CsCIPK开放阅读框长度为1 341 bp,编码446个氨基酸,蛋白质分子量为414234。蛋白功能域预测和多重对比显示,CsCIPK蛋白含有1个保守的N端激酶结构域和1个相对不保守的C端调节结构域,即丝氨酸/苏氨酸激酶结构域和NAF结构域。理化性质、亲/疏水性、无序化分析显示,CsCIPK属于疏水性蛋白,理论等电点为7.04,有4段无序化区域,其二级结构分析显示主要由α螺旋、不规则卷曲组成。通过实时荧光定量PCR对‘龙井43’和‘安吉白茶’中的CsCIPK表达特性进行分析。结果显示‘龙井43’中CsCIPK的相对表达量在高温、干旱及盐处理4 h、低温处理24 h时达到最高。‘安吉白茶’中CsCIPK的相对表达量在高温及盐处理4 h、低温及干旱处理1h时达到最高。CsCIPK在‘龙井43’的根中,‘安吉白茶’茎中表达量最高。不同浓度的GA和IBA处理‘龙井43’茶苗,结果显示0.2 mmol·L-1 GA处理后,CsCIPK表达量先升高后下降,6 d时处理组为对照组的62倍;0.6 mmol·L-1 IBA处理后,CsCIPK的表达量在3 d时显著高于对照组;不同浓度GA和IBA处理后,9 d时CsCIPK表达量均显著低于对照。 相似文献