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51.
52.
Tamara Schmey Corinn Small Severin Einspanier Lina Muñoz Hoyoz Tahir Ali Soledad Gamboa Betty Mamani German C. Sepulveda Marco Thines Remco Stam 《Environmental microbiology》2023,25(10):1830-1846
The wild relatives of modern tomato crops are native to South America. These plants occur in habitats as different as the Andes and the Atacama Desert and are, to some degree, all susceptible to fungal pathogens of the genus Alternaria. Alternaria is a large genus. On tomatoes, several species cause early blight, leaf spots and other diseases. We collected Alternaria-like infection lesions from the leaves of eight wild tomato species from Chile and Peru. Using molecular barcoding markers, we characterized the pathogens. The infection lesions were caused predominantly by small-spored species of Alternaria of the section Alternaria, like A. alternata, but also by Stemphylium spp., Alternaria spp. from the section Ulocladioides and other related species. Morphological observations and an infection assay confirmed this. Comparative genetic diversity analyses show a larger diversity in this wild system than in studies of cultivated Solanum species. As A. alternata has been reported to be an increasing problem in cultivated tomatoes, investigating the evolutionary potential of this pathogen is not only interesting to scientists studying wild plant pathosystems. It could also inform crop protection and breeding programs to be aware of potential epidemics caused by species still confined to South America. 相似文献
53.
Rafael Muñoz-Mas Franz Essl Mark van Kleunen Hanno Seebens Wayne Dawson Christine Marie V. Casal Emili García-Berthou 《Global Ecology and Biogeography》2023,32(9):1632-1644
Aim
Investigating major freshwater fish flows (translocations) between biogeographic regions and their temporal dynamics and also quantifying spatial patterns and temporal changes in the array of introduced species, and the emergence and distance between major donor and recipient regions.Location
Global.Time Period
1800–2020.Major Taxa Studied
Freshwater fishes.Methods
We analysed a global dataset on freshwater fish introductions (4241 events of 688 species). Freshwater fish flows were investigated with flow diagrams and χ2 tests, while PERMANOVA (permutational multivariate analysis of variance) was used to test the association between species and regions and temporal shifts. Cluster analysis revealed major recipient areas and composition of the introduced species. Finally, changes in distances between donor and recipient sites were tested with PERMANOVA.Results
The number of introductions between biogeographic regions mirrored the European and North American dominance before World War II (WWII) and the trends in recreational fishing, biocontrol programmes and food production, especially in the Sino-Oriental region, which has a long tradition of aquaculture and fishkeeping. Over the years, the origins and composition of introduced species changed uniquely in each biogeographic region, although the most introduced species are common to every region. Salmonids and other cold-water species were frequently introduced before the 1950s, whereas tropical ornamental and aquaculture species currently prevail. Distances between donor and recipient sites did not vary over the time. After WWII, the Sino-Oriental region consolidated its dominance and the Ethiopian and Neotropical regions emerged as new global donor and recipient regions.Main Conclusions
Global policy should focus on tropical ornamental and aquaculture species, which could benefit from global warming, especially in the Sino-Oriental region, because it currently dominates freshwater fish species flows, and the Ethiopian and Neotropical regions, because they recently emerged as important global donor and recipient regions of freshwater fish introductions. 相似文献54.
Yadira Rodríguez Silvia García Raquel Lebrero Raúl Muñoz 《Biotechnology and bioengineering》2023,120(11):3224-3233
Biogas biorefineries have opened up new horizons beyond heat and electricity production in the anaerobic digestion sector. Added-value products such as polyhydroxyalkanoates (PHAs), which are environmentally benign and potential candidates to replace conventional plastics, can be generated from biogas. This work investigated the potential of an innovative two-stage growth-accumulation system for the continuous production of biogas-based polyhydroxybutyrate (PHB) using Methylocystis hirsuta CSC1 as cell factory. The system comprised two turbulent bioreactors in series to enhance methane and oxygen mass transfer: a continuous stirred tank reactor (CSTR) and a bubble column bioreactor (BCB) with internal gas recirculation. The CSTR was devoted to methanotrophic growth under nitrogen balanced growth conditions and the BCB targeted PHB production under nitrogen limiting conditions. Two different operational approaches under different nitrogen loading rates and dilution rates were investigated. A balanced nitrogen loading rate along with a dilution rate (D) of 0.3 day−1 resulted in the most stable operating conditions and a PHB productivity of ~53 g PHB m−3 day−1. However, higher PHB productivities (~127 g PHB m−3 day−1) were achieved using nitrogen excess at a D = 0.2 day−1. Overall, the high PHB contents (up to 48% w/w) obtained in the CSTR under theoretically nutrient balanced conditions and the poor process stability challenged the hypothetical advantages conferred by multistage vs single-stage process configurations for long-term PHB production. 相似文献
55.
Strain distribution pattern in AXB and BXA recombinant inbred strains for loci on murine Chromosomes 10, 13, 17, and 18 总被引:1,自引:1,他引:0
Jian-Long Mu Jürgen K. Naggert Patsy M. Nishina Yin-Chai Cheah Beverly Paigen 《Mammalian genome》1993,4(3):148-152
Strain distribution patterns (SDPs) of selected loci previously mapped to murine Chromosomes (Chrs) 10, 13, 17, and 18 are reported for the AXB, BXA recombinant inbred (RI) strain set derived from the progenitor strains A/J (A) and C57BL/6J (B). The loci included the simple sequence length polymorphisms (D10Nds1, D10Mit2, D10Mit10, D10Mit14, D13Mit3, D13Nds1, D13Mit10, D13Mit13, D13Mit7, D13Mit11, D17Mit18, D17Mit10, D17Mit20, D17Mit3, D17Mit2, D18Mit17, D18Mit9, and D18Mit4), the restriction fragment length polymorphisms Pdea and Csfmr, and the biochemical marker AS-1. These loci were chosen because they map to genomic regions that had few or no genetic markers in the AXB, BXA RI set. Several of these loci also were typed in backcross progeny of matings of the (AXB)F1 to strain A or B. The strain distribution patterns for chromosomes 10, 13, 17, and 18 are reported, and the gene order and map distances determined from the backcross data. The addition of these markers to the AXB, BXA RI strain set increases the genomic region over which linkage for new markers can be detected. 相似文献
56.
Hu Xiaoyu Tang Ruibo Zhao Caijun Mu Ruiying Wang Ying Cao Yongguo Zhang Naisheng Fu Yunhe 《Probiotics and antimicrobial proteins》2023,15(1):74-81
Probiotics and Antimicrobial Proteins - Mastitis, common inflammation of the mammary gland, caused by various factors, is a challenge for the dairy industry. Escherichia coli (E. coli), a... 相似文献
57.
Aonio Bernao Isabel Meseguer María Victorina Aguilar María Carmen Martínez Para María José González Mu?oz 《Journal of trace elements in medicine and biology》2004,18(1):33-39
This 12-day study was conducted to evaluate the effects of three different levels of dietary chromium (100, 200, and 500 microg/day) in the form of chromium picolinate (CrPic) on growth and protein use in weaned rats. No significant effect of CrPic on body weight gain, food intake, or food conversion rate was observed. Elevated doses of CrPic seemed to increase muscle mass, either by stimulating protein anabolism by activation of insulin by chromium or by lowering protein degradation. However, these effects had no repercussions on overall growth, suggesting that any anabolic effect of chromium due to the action of insulin was probably marginal. 相似文献
58.
用放射配基结合法和高效液相色谱电化学法分别测定氟烷对慢性缺氧免心肌β肾上腺素能受体(简称β受体)和血浆儿茶酚胺的影响。结果表明:慢性缺氧后兔心肌β受体密度明显下降,受体亲和力无明显变化,血浆肾上腺素、去甲肾上腺素明显升高。缺氧吸入氟烷后兔心肌β受体密度进一步下降,亲和力增加,血浆肾上腺素、去甲肾上腺素无进一步变化。常氧吸入氟烷后心肌β受体密度无明显变化,亲和力升高,血浆肾上腺素、去甲肾上腺素反而降低。结果提示,氟烷抑制常氧兔交感神经活动而不能抑制缺氧兔交感神经活动,氟烷不改变常氧兔心肌β受体密度,但降低缺氧兔心肌β受体密度。β受体密度降低与缺氧后升高的儿茶酚胺下调β受体数目有关,同时可能与氟烷改变了缺氧心肌细胞膜脂质流动性使受体易向膜内移动有关。 相似文献
59.
喜马拉雅灰包菇SecotiumhimalaicumZangetDoi,由Dr.TeizoOgawa采于尼泊尔境内的喜马拉雅山带,据当地居民云:该菌为喜马拉雅雪人的一种食物。所谓雪人可能是高山雪线一带的动物。本文对该菌的分类特征和雪人的有关讨论作了介绍。原模式存日本国立科学博物馆。 相似文献
60.
Emili Saló Ana Maria Muñoz-Mármol José Ramon Bayascas-Ramirez Jordi Garcia-Fernàndez Agusti Miralles Andreu Casali Montserrat Corominas Jaume Baguñá 《Hydrobiologia》1995,305(1-3):269-275
To identify potential pattern control and cell determination and/or differentiation genes in the freshwater planarian Dugesial (G.) tigrina, we searched for homeobox genes of different types in the genome of this primitive metazoan. We applied two basic approaches: 1) Screening the cDNA library with degenerate oligonucleotides corresponding to the most conserved amino acid sequence from helix-3 of the homeodomain of each family; and 2) PCR amplification of genomic DNA or cDNA, using two sets of degenerated oligonucleotides corresponding to helices 1 and 3 of the homeodomain or two specific domains of the POU family. Using the first strategy we have identified and characterized two tissue-specific cell determination and/or differentiation NK-type homeobox genes. Using the second strategy we have identified several homeobox genes that belong to the HOM/Hox, paired (prd) or POU families. 相似文献