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2022 ◽  
Vol 806 ◽  
pp. 150555
Author(s):  
Jie Yi ◽  
Quanchao Zeng ◽  
Tangyingze Mei ◽  
Shengnan Zhang ◽  
Qi Li ◽  
...  

Biomolecules ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 144
Author(s):  
Michail I. Gladyshev ◽  
Alexander A. Makhrov ◽  
Ilia V. Baydarov ◽  
Stanislava S. Safonova ◽  
Viktor M. Golod ◽  
...  

Fatty acids (FA) of muscle tissue of Salvelinus species and its forms, S. alpinus, S. boganidae, S. drjagini, and S. fontinalis, from six Russian lakes and two aquacultures, were analyzed. Considerable variations in FA compositions and contents were found, including contents of eicosapentaenoic and docosahexaenoic acids (EPA and DHA), which are important indicators of fish nutritive value for humans. As found, contents of EPA+DHA (mg·g−1 wet weight) in muscle tissue of Salvelinus species and forms varied more than tenfold. These differences were supposed to be primarily determined by phylogenetic factors, rather than ecological factors, including food. Two species, S. boganidae and S. drjagini, had the highest EPA+DHA contents in their biomass and thereby could be recommended as promising species for aquaculture to obtain production with especially high nutritive value. Basing on revealed differences in FA composition of wild and farmed fish, levels of 15-17-BFA (branched fatty acids), 18:2NMI (non-methylene interrupted), 20:2NMI, 20:4n-3, and 22:4n-3 fatty acids were recommended for verifying trade label information of fish products on shelves, as the biomarkers to differentiate wild and farmed charr.


2022 ◽  
Author(s):  
Juanita Engelbrecht ◽  
Tuan A. Duong ◽  
Trudy Paap ◽  
Joseph Michael Hulbert ◽  
Juanita Joyce Hanneman ◽  
...  

Phytophthora cinnamomi is the causal agent of root rot, canker and dieback of thousands of plant species around the globe. This oomycete not only causes severe economic losses to forestry and agricultural industries, but also threatens the health of various plants in natural ecosystems. In this study, 380 isolates of P. cinnamomi from four avocado production areas and two regions of natural vegetation in South Africa were investigated using 15 microsatellite markers. These populations were found to have a low level of genetic diversity and consisted of isolates from three lineages. Shared genotypes were detected between isolates from avocado orchards and natural vegetation, indicating the movement of isolates between these areas. The population from the Western Cape natural vegetation had the highest genotypic diversity and unique alleles, indicating this could be the point of introduction of P. cinnamomi to South Africa. Index of association analysis suggested that five out of six populations were under linkage disequilibrium suggesting a clonal mode of reproduction whereas genotypes sampled from a recently established avocado orchard in the Western Cape were derived from a randomly recombined population. This study provided novel insights on the genetic diversity and spread of P. cinnamomi in South Africa. It also reported on the predominance of triploidy in natural occurring populations and provided evidence for recombination of P. cinnamomi for the first time. The presence of two dominant genotypes in all avocado production areas in South Africa highlight the importance of considering them in disease management and resistance breeding programmes.


2022 ◽  
Vol 9 ◽  
Author(s):  
Peijun Ju ◽  
Wenchao Yan ◽  
Jianliang Liu ◽  
Xinwei Liu ◽  
Liangfeng Liu ◽  
...  

As a sensitive, observable, and comprehensive indicator of climate change, plant phenology has become a vital topic of global change. Studies about plant phenology and its responses to climate change in natural ecosystems have drawn attention to the effects of human activities on phenology in/around urban regions. The key factors and mechanisms of phenological and human factors in the process of urbanization are still unclear. In this study, we analyzed variations in xylophyta phenology in densely populated cities during the fast urbanization period of China (from 1963 to 1988). We assessed the length of the growing season affected by the temperature and precipitation. Temperature increased the length of the growing season in most regions, while precipitation had the opposite effect. Moreover, the plant-growing season is more sensitive to preseason climate factors than to annual average climate factors. The increased population reduced the length of the growing season, while the growing GDP increased the length of the growing season in most regions (8 out of 13). By analyzing the impact of the industry ratio, we found that the correlation between the urban management of emerging cities (e.g., Chongqing, Zhejiang, and Guizhou) and the growing season is more significant, and the impact is substantial. In contrast, urban management in most areas with vigorously developed heavy industry (e.g., Heilongjiang, Liaoning, and Beijing) has a weak and insignificant effect on plant phenology. These results indicate that different urban development patterns can influence urban plant phenology. Our results provide some support and new thoughts for future research on urban plant phenology.


Author(s):  
Ramesh Kumar ◽  
R.S. Yadav ◽  
Amit Kumawat ◽  
Vinay Nangia ◽  
N.D. Yadava ◽  
...  

Background: Freshwater in sufficient quantity and adequate quality is a prerequisite for human societies and natural ecosystems. To adequately feed 9.3 billion people in 2050, consumptive water use (i.e. transpired water) by all food and fodder crops needs to increase from its present estimated level of 7000 km3/year to 12,586 km3/year. However, fresh water resources are increasingly getting scarce because of increased competition among a multitude of users. Getting agriculture to perform with progressively smaller allocation of renewable water resources will remain a challenge on global scale. To meet the challenge there is an urgent need to improve the crop water productivity to ensure the sustainability of agriculture. Methods: An experiment was carried out at village Menawali, Hanumangarh, Rajasthan during both kharif and rabi seasons to assess productivity, economics, N-uptake and water use of different crops. An area of 187 ha comprising 25 farmers irrigated by common irrigation channels were selected to collect the information. The information required i.e. soil, crop management, growth, phonological, yields, water balance, N-uptake and water use efficiency of each crops were collected from 15 farmers. Bt-cotton and clusterbean of kharif and wheat and Indian mustard in rabi were prominent crops, cotton-wheat, cotton-mustard, clusterbean-wheat and clusterbean-mustard were major cropping sequences of the study region. Result: In kharif season, Bt-cotton gave higher economic yields than clusterbean and amongst rabi season crops, economic yields of wheat and mustard were 4255, 1778 kg/ha, respectively. The economic yield of cropping sequences varied from 3741-6514 kg/ha and were higher for cotton-wheat (6218 kg/ha), intermediate for clusterbean-wheat (5785 kg/ha) and lower for cotton-mustard (3741 kg/ha) and clusterbean-mustard (3308 kg/ha). The cotton-wheat (₹1181.2 mm) sequence had highest water use. Clusterbean-wheat cropping system recorded highest water productivity (16.5 kg/ha mm) followed by clusterbean-mustard (14.9 kg/ha mm). The clusterbean-mustard (₹456/ha mm) cropping sequence was most profitable and fetched highest net return followed by clusterbean-wheat (₹383/ha mm).


Author(s):  
Bruce H Noden ◽  
Megan A Roselli ◽  
Scott R Loss

Abstract Urbanization alters components of natural ecosystems which can affect tick abundance and tick-borne disease prevalence. Likely due to these changes, tick-borne pathogen prevalence has increased in many U.S. urban areas. Despite the growing public health importance of tick-borne diseases, little is known about how they are influenced by urbanization in North America, especially in the central U.S. where several pathogens occur at or near their highest levels of incidence nationally. To determine whether urban development influences tick infection with bacteria and protozoa, we collected ticks at 16 parks across a gradient of urbanization intensity in Oklahoma City, Oklahoma, USA and tested them using a variety of PCR assays. Adult ticks tested positive for Rickettsia parkeri, R. amblyommatis, R. rhiphicephali, ‘Candidatus R. andeanae’, Ehrlichia chaffeensis, E. ewingii, Panola Mountain Ehrlichia, ‘Borrelia lonestari’, Theileria cervi, Babesia spp. Coco, and Cytauxzoon felis. These results indicate the presence of a high diversity of tick-borne bacteria and protozoa across an expanding urban area in the U.S. Great Plains. Although there appeared to be some risk of encountering tick-borne microorganisms across the entire urbanization gradient, E. chaffeensis, E. ewingii, and T. cervi-infected ticks and microbe diversity decreased with increasing urbanization intensity. We identified a low rate of coinfection between different microorganisms, with coinfected ticks mainly collected from sites in the least-urbanized areas. This study suggests the need for awareness of tick-borne disease risk throughout urban areas in the central U.S., and highlights a need for studies of tick host habitat use and movement in cities.


Soil Systems ◽  
2022 ◽  
Vol 6 (1) ◽  
pp. 8
Author(s):  
Sarah M. Denton-Thompson ◽  
Emma J. Sayer

Soil micronutrients limit crop productivity in many regions worldwide, and micronutrient deficiencies affect over two billion people globally. Microbial biofertilizers could combat these issues by inoculating arable soils with microorganisms that mobilize micronutrients, increasing their availability to crop plants in an environmentally sustainable and cost-effective manner. However, the widespread application of biofertilizers is limited by complex micronutrient–microbe–plant interactions, which reduce their effectiveness under field conditions. Here, we review the current state of seven micronutrients in food production. We examine the mechanisms underpinning microbial micronutrient mobilization in natural ecosystems and synthesize the state-of-knowledge to improve our overall understanding of biofertilizers in food crop production. We demonstrate that, although soil micronutrient concentrations are strongly influenced by soil conditions, land management practices can also substantially affect micronutrient availability and uptake by plants. The effectiveness of biofertilizers varies, but several lines of evidence indicate substantial benefits in co-applying biofertilizers with conventional inorganic or organic fertilizers. Studies of micronutrient cycling in natural ecosystems provide examples of microbial taxa capable of mobilizing multiple micronutrients whilst withstanding harsh environmental conditions. Research into the mechanisms of microbial nutrient mobilization in natural ecosystems could, therefore, yield effective biofertilizers to improve crop nutrition under global changes.


Author(s):  
Shannon Hunter ◽  
Rebecca McDougal ◽  
Nari Williams ◽  
Peter Scott

AbstractPhosphite is used to control and manage many phytophthora diseases in horticultural systems worldwide and natural ecosystems in Australia, Africa, New Zealand and parts of Northern America and Europe. Phosphite does not kill Phytophthora species, but inhibits growth while also stimulating host defence responses. Phytophthora species differ in their underlying tolerance to phosphite and isolates have been shown to acquire tolerance after prolonged exposure. Intra- and inter-specific variability in phosphite sensitivity is of interest to determine the efficacy and sustainability of phosphite for the treatment of phytophthora diseases, which continue to spread globally. Seven Phytophthora species were tested for their sensitivity to phosphite in vitro in a mycelial growth experiment. Phytophthora agathidicida was the species most sensitive to phosphite, being inhibited by 98.7% on average at the lowest phosphite treatment (15 µg/mL phosphite), followed by P. aleatoria, P. cinnamomi, P. pluvialis, P. multivora, P. kernoviae and P. citricola. Huge intraspecific variability was observed with P. kernoviae, which raises the question of whether diseases caused by P. kernoviae such as phytophthora needle blight of Pinus radiata could be managed effectively with phosphite. Further work is required to determine the phosphite sensitivity of different introduced and native Phytophthora species growing in key hosts and whether tolerance observed in vitro is also expressed in vivo.


2022 ◽  
Author(s):  
Indra Kumar Kasi ◽  
Mohinder Singh ◽  
Kanchhi Maya Waiba

Abstract Invasive species are a major danger to agronomic and natural ecosystems, and due to environmental concerns about pesticide use, EPNs have the potential to replace larvicidal action in pest management. The goal was to see how well local isolates of Steinernema feltiae (HR1) and Heterorhabditis bacteriophora (HR2) controlled invasive species when combined with low-toxicity pesticides. HR1 + Spinosad, chlorantraniliprole produced over 90% mortality in larvae at 96 hours, while HR2 + Spinosad, chlorantraniliprole caused over 95% mortality at 96 hours. After treatment, the high dose was regarded the least hazardous technique for controlling fall armyworm. At the high dose, HR1 + Spinosad, chlorantraniliprole produced larvae death of over 100 percent at 96 hours, and HR2 + Spinosad, chlorantraniliprole caused mortality of over 97.50 percent at 96 hours, and should be considered as a least hazardous strategy for T. absoluta management. Controlling larvae mortality of above 100% at 96 hours in combination with low-toxicity insecticide dosages should be included as a least harmful technique to control T. absoluta. The results showed that these HR2 strains have high pathogenicity against T. absoluta and S. frugiperda and have potential for control in integrated approaches, causing 100 percent and 90.00 percent mortality of T. absoluta and S. frugiperda at 96 hours at the high dose as a least toxic strategy to control.


2022 ◽  
Vol 10 (1) ◽  
pp. 138
Author(s):  
Arnaud Bridier ◽  
Romain Briandet

Microbial biofilms are found everywhere and can be either beneficial or detrimental, as they are involved in crucial ecological processes and in severe chronic infections. The functional properties of biofilms are closely related to their three-dimensional (3D) structure, and the ability of microorganisms to collectively and dynamically shape the community spatial organization in response to stresses in such biological edifices. A large number of works have shown a relationship between the modulation of the spatial organization and ecological interactions in biofilms in response to environmental fluctuations, as well as their emerging properties essential for nutrient cycling and bioremediation processes in natural environments. On the contrary, numerous studies have emphasized the role of structural rearrangements and matrix production in the increased tolerance of bacteria in biofilms toward antimicrobials. In these last few years, the development of innovative approaches, relying on recent technological advances in imaging, computing capacity, and other analytical tools, has led to the production of original data that have improved our understanding of this close relationship. However, it has also highlighted the need to delve deeper into the study of cell behavior in such complex communities during 3D structure development and maturation— from a single-cell to a multicellular scale— to better control or harness positive and negative impacts of biofilms. For this Special Issue, the interplay between biofilm emerging properties and their 3D spatial organization considering different models, from single bacteria to complex environmental communities, and various environments, from natural ecosystems to industrial and medical settings are addressed.


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