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71.
Spodoptera frugiperda (J. E. Smith) is a highly adaptable polyphagous migratory pest in tropical and subtropical regions. Small heat shock proteins (sHsps) are molecular chaperones that play important roles in the adaptation to various environment stressors. The present study aimed to clarify the response mechanisms of S. frugiperda to various environmental stressors. We obtained five S. furcifera sHsp genes (SfsHsp21.3, SfsHsp20, SfsHsp20.1, SfsHsp19.3, and SfsHsp29) via cloning. The putative proteins encoded by these genes contained a typical α-crystallin domain. The expression patterns of these genes during different developmental stages, in various tissues of male and female adults, as well as in response to extreme temperatures and UV-A stress were studied via real-time quantitative polymerase chain reaction. The results showed that the expression levels of all five SfsHsp genes differed among the developmental stages as well as among the different tissues of male and female adults. The expression levels of most SfsHsp genes under extreme temperatures and UV-A-induced stress were significantly upregulated in both male and female adults. In contrast, those of SfsHsp20.1 and SfsHsp19.3 were significantly downregulated under cold stress in male adults. Therefore, the different SfsHsp genes of S. frugiperda play unique regulatory roles during development as well as in response to various environmental stressors.  相似文献   
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Since the first case report on COVID-19, its transmission took place rapidly across the globe. Currently, it is reported to be spread into a total of 216 countries and territories. The suppression on industrial and gasoline burning activities accompanied after COVID-19 lock down favorably boosted the nature to restore its deteriorated sections such as in air with the improved Air quality index and in water bodies with the natural tone of purity. Increased use of anti-viral drugs along with herbal therapies has been observed at mass scale as global intervention to prevent the disease. The use of personal protective equipment and disinfection strategies for the control of pandemic has dramatically increased the pollution of plastic and medical waste. This article aims to forecast and highlight the evidence-based impact/changes (+ive and -ive) of coronavirus on the environment, global interventions to prevent the disease along with the levels of effectiveness of personal used protective equipment to stop the spread of coronavirus.  相似文献   
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The outbreak of the coronavirus disease 2019 (COVID-19) continues to constitute an international public health emergency. Seasonality is a long-recognized attribute of many viral infections of humans. Nevertheless, the relationship between environmental factors and the spread of infection, particularly for person-to-person communicable diseases, remains poorly understood. This study explores the relationship between environmental factors and the incidence of COVID-19 in 188 countries with reported COVID-19 cases as of April 13, 2020. Here we show that COVID-19 growth rates peaked in temperate zones in the Northern Hemisphere during the outbreak period, while they were lower in tropical zones. The relationships between COVID-19 and environmental factors were resistant to the potentially confounding effects of air pollution, sea level, and population. To prove the effect of those factors, study, and analysis of the prevalence of COVID-19 in Italy, Spain, and China was undertaken. A fuzzy logic system was designed to predict the effects of that variables on the rate of viral spread of COVID-19.  相似文献   
75.
沿长江中下游(宜昌-铜陵段)13座城市共37个位点,分别于丰水期和枯水期对岸带的湿生植物进行调查,从物种和系统发育2个维度研究群落的构建机制,并结合环境和空间因子探讨其驱动因素。结果显示:(1)丰水期湿生植物群落的α多样性高于枯水期,且丰水期α多样性主要与水分条件呈正相关,而枯水期则主要与温度和土壤总氮含量有关。(2)丰水期的系统发育结构指数呈聚集趋势,暗示生境过滤起着主导作用,而枯水期的NRI(net relatedness index)和NTI(nearest taxon index)呈不同趋势,暗示存在近期的群落分化。(3)群落的α多样性在物种层面和系统发育层面存在显著关联性,其多样性水平可在一定程度上互为表征。(4)长江中下游沿岸湿生植物群落的构建机制在不同时期存在差异,丰水期的群落构建是环境筛选和扩散限制共同作用的结果,且以环境筛选作用占主导,而枯水期的群落构建仅在物种层面受一定程度环境筛选作用的影响。(5)大生境的温度变化、微生境的土壤水分和养分条件是影响长江中下游岸带湿生植物群落差异的主要驱动因素。该研究结果可为长江中下游岸带湿地生态系统的管理和保护提供科学支持。  相似文献   
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Abstract

Human-induced and natural stress factors can affect fine roots and ectomycorrhizas. Therefore they have potential utility as indicators of environmental change. We evaluated, through meta-analysis, the magnitude of the effects of acidic deposition, nitrogen deposition, increased ozone levels, elevated atmospheric carbon dioxide, and drought on fine roots and ectomycorrhizal (ECM) characteristics. Ectomycorrhizal colonization was an unsuitable parameter for environmental change, but fine root length and biomass could be useful. Acidic deposition had a significantly negative impact on fine roots, root length being more sensitive than root biomass. There were no significant effects of nitrogen deposition or elevated tropospheric ozone on the quantitative root parameters. Elevated CO2 had a significant positive effect. Drought had a significantly negative effect on fine root biomass. The negative effect of acidic deposition and the positive effect of elevated CO2 increased over time, indicating that effects were persistent contrary the other factors. The meta-analysis also showed that experimental conditions, including both laboratory and field experiments, were a major source of variation. In addition to quantitative changes, environmental changes affect the species composition of the ectomycorrhizal fungal community.  相似文献   
79.
Specific root length as an indicator of environmental change   总被引:4,自引:0,他引:4  
Abstract

Specific root length (SRL, m g?1) is probably the most frequently measured morphological parameter of fine roots. It is believed to characterize economic aspects of the root system and to be indicative of environmental changes. The main objectives of this paper were to review and summarize the published SRL data for different tree species throughout Europe and to assess SRL under varying environmental conditions. Meta-analysis was used to summarize the response of SRL to the following manipulated environmental conditions: fertilization, irrigation, elevated temperature, elevated CO2, Al-stress, reduced light, heavy metal stress and physical disturbance of soil. SRL was found to be strongly dependent on the fine root classes, i.e. on the ectomycorrhizal short roots (ECM), and on the roots <0.5 mm, <1 mm, <2 mm and 1 – 2 mm in diameter SRL was largest for ECM and decreased with increasing diameter. Changes in soil factors influenced most strongly the SRL of ECM and roots <0.5 mm. The variation in the SRL components, root diameter and root tissue density, and their impact on the SRL value were computed. Meta-analyses showed that SRL decreased significantly under fertilization and Al-stress; it responded negatively to reduced light, elevated temperature and CO2. We suggest that SRL can be used successfully as an indicator of nutrient availability to trees in experimental conditions.  相似文献   
80.
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