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61.

Background

Traditional markets outstandingly contribute to conservation of biocultural diversity, social relations, and cultural values. These markets reflect life strategies and forms people of a region interact with their biodiversity and territories, as well as traditional ecological knowledge and management practices. To understand the factors motivating plant and mushroom management, we analyzed the resources cultural and economic values, their role in people’s subsistence, and the relation of these values with the resources spatial and temporal availability. Our study based on the supposition that traditional markets are settings of interchange of resources with the highest importance for people’s life in a region. Also, that the cultural, economic, and ecological factors influence values of the resources, and the demand on them determine pressures on the most valuable resources which, when scarce, motivate management innovation, otherwise become extinct.

Methods

We documented cultural, economic, and ecological aspects, as well as management techniques of wild and weedy plants and mushrooms interchanged in three traditional markets of the Pátzcuaro Lake region, in central-western Mexico. For doing that, from February 2015 to March 2018, we conducted 175 visits to markets and 89 semi-structured interviews to producers, gatherers, and sellers of wild and weedy plants and mushrooms. Based on participant observation and interviews, we identified variables related to culture, economic, and ecological aspects, as well as management regimes of resources and management systems, which were documented and used as indicators for quantitative analyses. Through principal components analyses (PCA), we determined the indexes of cultural and economic importance (ICEI), management intensity (IMI), and ecological risk (IR) of the resources studied. For conducting that, we classified plant and mushroom species according to their cultural, economic, ecological, and technological indicators, respectively. The score of the first principal component was considered as the index for each group of variables, respectively. To identify relations between cultural importance and risk, we performed linear regression analyses between ICEI and IR indexes.

Results

We recorded 57 species of wild and weedy plants used as food, medicine, and ornamental, and 17 species of edible mushrooms. The variables with the highest weight in the ICEI are related to the need of a resource according to people, its recognizing, the number of communities and markets offering it in markets, its explicit preference expressed by people, the effort invested in obtaining it, and the form it is interchanged. Gathering is practiced in all mushrooms and wild and weedy plants from forests and agricultural areas; 11 species in addition receive 1 or more forms of management (enhancing, selective let standing, propagation through seeds or vegetative parts, transplantation, and/or protection). The management intensity and complexity are explained by variables related to management practices and systems. Plants receiving selective management have the higher management intensity. Silvicultural management (in situ management in forests) was recorded in all species of mushrooms, as well as in more than 80% of medicinal, ceremonial and ornamental plants, and in more than 50% of the edible plants. In agricultural systems, people manage more than 90% of the edible plants recorded to be under a management regime, 25% of the managed medicinal plants, and 30.7% of the managed ceremonial and ornamental plants. In homegardens, people manage 41.6% of the medicinal plants recorded and 26.6% of the edible plants, to have them available near home. Nearly 63% of the species interchanged in the markets studied are gathered in forests without any other management form. In this group are included all mushroom species, 61.5% of ceremonial/ornamental plants, 50% of medicinal, and 33.3% of edible plants. The linear regression between ICEI an IER is significantly negative for edible species with high management intensity R2?=?0.505 (p?=?0.0316), because of their management. But in medicinal and ornamental plants, the risk is high if the cultural importance increases, even when management practices like transplanting and propagation in homegardens are carried out.

Conclusions

Traditional markets are settings of interchange of products, knowledge, and experiences, where the ongoing factors and processes motivating management innovation can be identified and documented. This approach allows documenting processes occurring at regional level but would be benefited from deeper studies at local level in communities.
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An understanding of biocontrol activities is important when developing microorganism‐based alternatives to conventional fungicides. From our bacterial collection, we selected two strains (BBC023 and BBC047) for their outstanding antagonistic capacity against fungal phytopathogens and growth‐promoting abilities towards Arabidopsis thaliana. According to physiological and molecular characterizations, both strains were classified as Bacillus amyloliquefaciens and were tested against Botrytis cinerea in vitro and in a tomato. Both strains secrete lipopeptide‐like compounds that contribute to their in vitro antagonism. SEM‐images showed altered B. cinerea mycelial structures that were consistent with previous reports of the direct action of lipopeptides against fungal hyphae. The strains were applied to the roots (R), leaves (foliar ‐ F) or root/leaves (R/F) on tomato plants. All treatments significantly reduced the severity of B. cinerea infection (measured as a control index). However, only root applications (R and R/F) led to growth promotion in the tomato plants. We detected the production of indole acetic acid (IAA) and 2,3‐butanediol as growth promotion traits in the two strains. For both strains, the R/F treatment showed the highest control index, suggesting a synergic effect of direct antagonism against B. cinerea and resistance induction in the plant. In addition, in vitro antagonism of BBC023 and BBC047 against B. cinerea was similar; whereas in the F application, strain BBC047 significantly improved plant resistance and maintained a higher population density over time on tomato leaves, compared to BBC023. BBC047 was also able to produce a complex and robust biofilm in Msgg medium compared with that of BBC023. We linked the reduced biocontrol of BBC023 on leaves with its limited ability to generate robust biofilms and colonize the phylloplane. At last, we highlight the potential of the native Bacillus strains as promising alternatives for the development of bioproducts for sustainable agriculture.  相似文献   
64.
The effect of pH and transmembrane pH on the efficiency of the proton pump of the mitochondrialbc 1 complex bothin situ and in the reconstituted state was studied. In both cases the H+/e ratio for vectorial proton translocation by thebc 1 complex respiring at the steady state, under conditions in which the transmembrane pH difference (pH) represents the only component of the proton motive force (p), was significantly lower than that measured under level flow conditions. The latter amounts, at neutral pH, to 1 (2 including the scalar H+ release). In the reconstituted system steady-state pH was modulated by changing the intravesicular buffer as well as the intra/extra-liposomal pH. Under these conditions the H+/e ratio varied inversely with the pH. The data presented show that pH exerts a critical control on the proton pump of thebc 1 complex. Increasing the external pH above neutrality caused a decrease of the level flowH +/e ratio. This effect is explained in terms of proton/electron linkage inb cytochromes.  相似文献   
65.
Brefeldin A, an inhibitor of protein secretion, caused typical alterations to the endomembrane system with limited effects on viability when given to unorganized carrot cells growing in suspension. When given to the same cells during particular stages of embryogenesis, it caused similar endomembrane lesions and an almost complete arrest of the embryogenic process. Addition of conditioned medium containing extracellular secreted proteins to the embryos during treatment with Brefeldin A allowed acquisition of polarity and the continuation of a quasi-normal embryogenic process. Received: 4 December 1996 / Accepted: 4 March 1997  相似文献   
66.
Caspases are cysteine proteases, which play important roles in different processes including, apoptosis and inflammation. Caspase-12, expressed in mouse and human, is classified as an inflammatory caspase. However, in humans caspase-12 gene has acquired different mutations that result in the expression of different variants. Caspase-12 is generally recognized as a negative regulator of the inflammatory response induced by infections, because it inhibits the activation of caspase-1 in inflammasome complexes, the production of the pro-inflammatory cytokines IL-1β and IL-18 and the overall response to sepsis. In contrast, caspase-4, the human paralog of caspase-12, exerts a positive modulatory action of the inflammatory response to infectious agents. The role of caspase-12 and caspase-4 in inflammation associated with cerebral ischemia, a condition that results from a transient or permanent reduction of cerebral blood flow, is still unknown. Among the mechanisms involved in ischemic brain injury, apoptosis and inflammation have important roles. Under these conditions, disturbances in the homeostasis of the endoplasmic reticulum (ER) take place, leading to ER stress, caspase activation and apoptosis. Caspase-12 up-regulation and processing has been observed after the ischemic episode but its role in apoptosis is controversial. Cleavage of caspase-4 also occurs during ER stress but its role in ischemic brain injury is unknown. Throughout this review evidence supporting a role of caspase-12 and caspase-4 on the modulation of the inflammatory response to infection and their potential contribution to ER stress-induced apoptosis, is discussed. Understanding the actions of rodent caspase-12 and human caspase-4 will help us to elucidate their role in different pathological conditions, which to date is not well understood.  相似文献   
67.
A strain of Lasiodiplodia mediterranea, a fungus associated with grapevine decline in Sicily, produced several metabolites in liquid medium. Two new dimeric γ‐lactols, lasiolactols A and B ( 1 and 2 ), were characterized as (2S*,3S*,4R*,5R*,2′S*,3′S*,4′R*,5′R*)‐ and (2R*,3S*,4R*,5R*,2′R*,3′S*,4′R*,5′R*)‐(5‐(4‐hydroxymethyl‐3,5‐dimethyl‐tetrahydro‐furan‐2‐yloxy)‐2,4‐dimethyl‐tetrahydro‐furan‐3‐yl]‐methanols by IR, 1D‐ and 2D‐NMR, and HR‐ESI‐MS. Other four metabolites were identified as botryosphaeriodiplodin, (5R)‐5‐hydroxylasiodiplodin, (–)‐(1R,2R)‐jasmonic acid, and (–)‐(3S,4R,5R)‐4‐hydroxymethyl‐3,5‐dimethyldihydro‐2‐furanone ( 3  –  6 , resp.). The absolute configuration (R) at hydroxylated secondary C‐atom C(7) was also established for compound 3 . The compounds 1  –  3 , 5, and 6 , tested for their phytotoxic activities to grapevine cv. Inzolia leaves at different concentrations (0.125, 0.25, 0.5, and 1 mg/ml) were phytotoxic and compound 5 showed the highest toxicity. All metabolites did not show in vitro antifungal activity against four plant pathogens.  相似文献   
68.
The L1014F mutation in the voltage‐sodium channel gene has been associated with resistance to DDT and pyrethroids in various arthropod species including mosquitoes. We determined the frequency of the L1014F kdr mutation in 16 field populations of Culex quinquefasciatus from Northeastern Mexico collected between 2008 and 2013. The L1014F was present in all populations analyzed with the lowest frequency (3.33%) corresponding to the population from Monclova collected in 2012, and the highest frequency (63.63%) from the Monterrey population collected in 2012. The presence of a kdr mutation in populations of Cx. quinquefasciatus from northeastern Mexico provides evidence of pyrethroid resistance. This requires a special attention, considering that pyrethroid‐based insecticides are commonly used in vector‐control campaigns, especially against Aedes aegypti (L.).  相似文献   
69.
The synthesis of cytochrome oxidase in Saccharomyces cerevisiae was recently shown to require a protein encoded by the nuclear gene COX10. This protein was found to be homologous to the putative protein product of the open reading frame ORF1 reported in one of the cytochrome oxidase operons of Paracoccus denitrificans. In the present study we demonstrate the existence in yeast of a second nuclear gene, COX11, whose encoded protein is homologous to another open reading frame (ORF3) present in the same operon of P. denitrificans. Mutations in COX11 elicit a deficiency in cytochrome oxidase. In this and in other respects cox11 and cox10 mutants have very similar phenotypes. An antibody has been obtained against the yeast COX11 protein. The antibody recognizes a 28 kd protein in yeast mitochondria, consistent with the size of the protein predicted from the sequence of COX11. The COX11 protein is tightly associated with the mitochondrial membrane but is not a component of purified cytochrome oxidase. An analysis of cytochrome oxidase subunits in wild type and in a cox11 mutant suggests that the COX11 protein is not required either for synthesis or transport of the subunit polypeptides into mitochondria. It seems more probable that COX11 protein exerts its effect at some terminal stage of enzyme synthesis, perhaps in directing assembly of the subunits.  相似文献   
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