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1.
Rev. biol. trop ; 70(1)dic. 2022.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1423022

RESUMO

Introducción: El Páramo es uno de los ecosistemas más afectados por actividades humanas, lo que aumenta la necesidad de estudios fenológicos como base para el manejo y la conservación. Objetivo: Describir la feno-morfología de Miconia ligustrina y Miconia elaeoides. Métodos: De septiembre 2019 a febrero 2020, y de abril 2021 hasta agosto del mismo año, se monitoreó la fenología de 12 individuos de cada especie. Adicionalmente, se vincularon datos fenológicos de ejemplares de herbario, para corroborar los resultados obtenidos. En los dos conjuntos de datos, se describió su distribución usando estadística circular, además, se obtuvieron registros de precipitación y temperatura del área. Adicionalmente, se describió la morfometría de cada especie. Resultados: El pico de floración de M. lingustrina es en abril, y la fructificación se concentra entre junio y julio; M. elaoides, florece de forma masiva en enero, con la máxima producción de frutos en mayo. Hubo correlación entre fenología y lluvias: la floración se da en época seca y la fructificación en la época lluviosa. Las especies difieren en morfología, pero, como en otras especies de Miconia, las flores y frutos son pequeños (aprox. 5 mm). Conclusión: La floración se presenta en la época seca y la fructificación en la época lluviosa, cuando las tasas de fotosíntesis son bajas y la frugivoría incrementa. Este patrón fenológico favorece la dispersión óptima de semillas.


Introduction: Paramos are among the ecosystems that are most affected by anthropic activities, increasing the need for phenological studies as a basis for management and conservation. Objective: To describe the pheno-morphology of Miconia ligustrina and Miconia elaeoides. Methods: From September 2019 to February 2020, and from April 2021 to August of the same year, the phenology of 12 individuals of each species was monitored. Additionally, phenological data of herbariums were linked to corroborate obtained results. In the two data sets, distribution of data was described using circular statistics; in addition, we recorded the precipitation and temperature in the area. Additionally, we described the morphometry of each species. Results: The flowering peak of M. ligustrina is in April, and fruiting concentrates between June and July; in M. elaeoides, flowering is massive in January, and the highest fruit production in May. The phenology was correlated with rainfall: flowering takes place in the dry season and fruiting in the rainy season. The species differ morphologically, but, as in other Miconia species, the flowers and fruits are small (approx. 5 mm). Conclusions: Flowering occurs in the dry season and fructification in the rainy season, when the photosynthetic rate is low and frugivory increases. This phenological pattern favors optimal seed dispersal.


Assuntos
Melastomataceae/crescimento & desenvolvimento , Myrtales/anatomia & histologia , Biologia , Colômbia , Flores
2.
Rev. colomb. biotecnol ; 24(2): 46-58, jul.-dic. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1423774

RESUMO

RESUMEN Ganoderma lucidum es un basidiomiceto de pudrición blanca estudiado especialmente por sus atributos medicinales. No obstante, la información sobre la suplementación de los medios de cultivo con metales como Zn, Li, Mn, Cu es escasa aun conociendo que la presencia de metales en los sustratos mejora las características de los basidiomas obtenidos e incrementa su productividad. El objetivo fue evaluar las actividades enzimáticas lacasa (Lc) y manganeso peroxidasa (MnP), la fructificación y eficiencia biológica (EB) de G. lucidum en cultivos sólidos formulados con residuos agroindustriales (aserrín de roble, cascarilla de café, salvado de maíz) suplementados con dos niveles de sal de manganeso II (0,05 % y 0,1 % p/p) y una formulación sin adición de la sal de manganeso. Las actividades enzimáticas se determinaron durante 98 días del ciclo productivo, con toma de muestras semanales. El tratamiento uno (0,05 % p/p de MnSO4H2O) suministró la mayor EB del cultivo con 25,90 ± 2,12 % y los mayores títulos de actividades ligninolíticas en el tiempo con 0,7299 UE/g s.s. de MnP a los 35 días de fermentación y 4,1 760 UE/g s.s para la actividad de Lc a los 42 días de proceso con relación a los tratamientos dos y control. Asimismo, hubo una disminución del ciclo de cultivo del hongo para los tratamientos uno (83 días) y dos (95 días) en comparación con el tratamiento control (117 días). Los resultados de este trabajo son promisorios para cultivadores industriales de G. lucidum, ya que la suplementación de los sustratos con Mn incrementa la productividad de los cultivos.


ABSTRACT Ganoderma lucidum is a white rot basidiomycete specially studied for its medicinal attributes. However, the information on the supplementation of the substrate with metals such as Zn, Li, Mn, Cu and others is scarce. Even knowing that the presence of metals in the substrates improves the characteristics of the basidiomes produced and increases their productivity. The objective was to evaluate the enzymatic activities laccase (Lc) and manganese peroxidase (MnP). The fructification and biological efficiency (BE) of G. lucidum in solid culture formulated with agroindustrial residues, (oak sawdust, coffee husk, bran corn) supplemented with two levels of manganese II salt, (0.05 % and 0.1 % w/ w) and a formulation without addition of manganese II salt. Enzymatic activities were determined during 98 days of the production cycle, with weekly sampling. Treatment one (0.05 % w/w MnSO4.H2O) provided the highest BE of the culture with 25.90 ± 0.54% and the highest titers of ligninolytic activities, in the time with 0.7299 EU/g d.s for MnP at 35 days of fermentation and 4.1760 EU/g d.s for Lc activity at 42 days of process, in relation to treatments two and control. Likewise, there was a decrease in the fungus culture cycle for treatments one (83 days) and two (95 days) compared to the control treatment (117 days). The results of this work are promising for industrial growers of G. lucidum, since the supplementation of the substrates with Mn increase the productivity of the cultures.

3.
Appl Microbiol Biotechnol ; 106(12): 4787-4799, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35759038

RESUMO

Morels (Morchella spp.) are of great economic and scientific value. Paecilomyces penicillatus can cause white mold disease (WMD) widely emerging on morel ascocarps and is also a potential factor causing morel fructification failure. 1-octen-3-ol is a mushroom volatile compound with broad-spectrum antimicrobial activities. This study aimed to control the morel disease caused by P. penicillatus through suppressing P. penicillatus in the soil cultivated with Morchella sextelata using 1-octen-3-ol. Safe concentration of 1-octen-3-ol was estimated by comparing its inhibitory effect against P. penicillatus and M. sextelata, respectively, with mycelium-growth experiments on agar plates. The results showed that M. sextelata possesses a higher tolerance to 1-octen-3-ol than P. penicillatus with a 1-octen-3-ol concentration between 0 and 200 µL/L. Based on that, a sandy soil was supplemented with low (50 µL/L) or high concentration (200 µL/L) of 1-octen-3-ol. The effects of 1-octen-3-ol on soil microbial communities, WMD incidence, and morel yield were investigated. Compared to the non-supplemented control group, the incidence of WMD and the proportion of Paecilomyces in the soils of low- and high-concentration treatment groups were significantly decreased, corresponding to a significant increase in morel ascocarp yield. It suggests that 1-octen-3-ol effectively suppressed P. penicillatus in the soil, thereby reducing the severity of WMD and improving the morel yield. The diversity of soil bacterial communities was also altered by 1-octen-3-ol supplement. The proportion of Rhodococcus spp. in the soil was positively correlated with the 1-octen-3-ol concentration and ascocarp yield, suggesting its potential role in improving morel yield. KEY POINTS: • A novel method for morel disease suppression was proposed. • Paecilomyces in soil affects white mold disease and fructification yield of morel. • 1-Octen-3-ol suppresses Paecilomyces and alters bacterial community in soil.


Assuntos
Agaricales , Paecilomyces , Bactérias , Octanóis/farmacologia , Solo
4.
Microbiol Spectr ; 9(2): e0022921, 2021 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-34643439

RESUMO

Black morel is a widely prized ascomycetous mushroom with culinary value. It was once uncultivable but can now be cultivated routinely in ordinary farmland soils. Large-scale morel farming sometimes encounters nonfructification for unknown reasons. In spring 2020, many morel farms in the area of Chengdu-Plain, China, exhibited no fructification at all, causing disastrous economic loss to the farmers. To determine potential ecological factors associated with the different performance of morel production in these farms, 21 affected sites versus 11 sites with normal fructification performance were analyzed to compare soil microbiota and physiochemical characteristics during fructification. The results indicated that soil physiochemical characteristics were unlikely to be a major reason for the difference between successful fructification and nonfructification. The soils with successful fructification had significantly higher diversity in both the fungal and bacterial communities than those with nonfructification. Morel yield was positively correlated with the α-diversity of fungal communities. The higher diversity of the successfully fructified soils was contributed by community evenness rather than taxonomic richness. In contrast, most nonfructification soils were dominated by a high proportion of a certain fungal genus, typically Acremonium or Mortierella, in the fungal communities. Our findings demonstrate the importance of microbial ecology to the large-scale agroindustry of soil-cultivated mushrooms. IMPORTANCE Saprotrophic mushrooms cultivated in soils are subject to complex influences from soil microbial communities. Research on growing edible mushrooms has revealed connections between fungi and a few species of growth-promoting bacteria colonizing the mycosphere. The composition and diversity of the whole microbial community may also have an influence on the growth and production of soil-saprotrophic mushrooms. Morel mushrooms (Morchella spp.) are economically and culturally important and are widely prized throughout the world. This study used the large-scale farming of morels as an example of an agroecosystem for soil-saprotrophic mushroom cultivation. It demonstrated a typical pattern of how the microbial ecology in soil agroecosystems, especially the α-diversity level and community evenness among soil fungal taxa, could affect the production of high-value cash crops and the income of farmers.


Assuntos
Ascomicetos/metabolismo , Micobioma/fisiologia , Microbiologia do Solo , Solo/química , Agricultura , Basidiomycota/metabolismo , Produtos Agrícolas
5.
J Fungi (Basel) ; 7(5)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069435

RESUMO

Cyclocybe parasitica is a wood-destroying parasitic edible mushroom growing on diverse broad-leafed trees in New Zealand and other Pacific areas. Recent molecular systematics of European Cyclocybe aegerita, a newly delimited Asian phylum and of related species, corroborated the distinction of the chiefly saprobic cultivated edible mushroom C. aegerita from C. parasitica. Here, we show that C. parasitica exhibits a morpho-physiological trait characteristic to its European cousin, i.e., monokaryotic fruiting sensu stricto (basidiome formation without mating). Monokaryotic fruiting structures formed by C. parasitica ICMP 11668-derived monokaryons were categorized into four phenotypes. One of them displays ulcer-like structures previously reported from bracket fungi. Histology of dikaryotic and monokaryotic C. parasitica fruiting structures revealed anatomical commonalities and differences between them, and towards monokaryotic fruiting structures of C. aegerita. Mating experiments with C. parasitica strains representative of each fruiting phenotype identified compatible sibling monokaryons. Given reports on hypothetically monokaryotic basidiome field populations of 'C. aegerita sensu lato', it seems worthwhile to prospectively investigate whether monokaryotic fruiting s.str. occurs in nature. Sampling from such populations including karyotyping, comparative -omics, and competition assays may help to answer this question and provide evidence whether this trait may confer competitive advantages to a species capable of it.

6.
Ticks Tick Borne Dis ; 12(1): 101579, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33080518

RESUMO

In spring 2019, forecasts of the incidence of tick-borne encephalitis (TBE) for the next 2 years, i.e. 2019 and 2020, were made for the first time. For this purpose, negative binomial regression models with 4-5 predictors were fitted to the time series of annual human TBE incidences from Austria, Germany, and Switzerland. The most important predictor for TBE incidences is the fructification index of the European beech (Fagus sylvatica) 2 years prior as a proxi for the intensity of the TBE virus transmission cycle. These forecasts were repeated in spring 2020 after the updated predictors and the confirmed TBE cases for 2019 became available. Forecasting TBE incidences for 2020 and 2021 results in 156 ±â€¯19 and 131 ±â€¯23 TBE cases for Austria, 663 ±â€¯95 and 543 ±â€¯112 TBE cases for Germany as well as 472 ±â€¯56 and 350 ±â€¯62 TBE cases for Switzerland. The newly implemented operational TBE forecasts will be verified every year with confirmed TBE cases. An initial verification for 2019 demonstrates the high reliability of the forecasts.


Assuntos
Encefalite Transmitida por Carrapatos/epidemiologia , Fagus/fisiologia , Previsões/métodos , Áustria/epidemiologia , Distribuição Binomial , Alemanha/epidemiologia , Humanos , Incidência , Análise de Regressão , Suíça/epidemiologia
7.
Ticks Tick Borne Dis ; 11(5): 101437, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32723631

RESUMO

The forecast of human tick-borne encephalitis (TBE) incidence for the next years has been on the research agenda of epidemiologists since the discovery of this tick-borne zoonosis. Based on models to explain the trend as well as the low- and high-frequency oscillations in the Austrian TBE incidence series, TBE forecasts for Austria, Germany and Switzerland are presented here. For this purpose, generalized linear models (GLMs) of type negative binomial regression were calibrated with the TBE incidences of the period 1991-2018 to forecast the TBE incidences 2019 and 2020. The GLMs require only 4-5 predictors, 2 of which are large-scale synchronized over Central Europe and used for all 3 countries. Predictors used include the demographic parameters total population and net migration rate, the Scandinavian index which describes the large-scale atmospheric circulation patterns, the fructification index of the European beech (Fagus sylvatica) 2 years prior as a proxy for the intensity of the TBE virus transmission cycle, and the national TBE vaccination coverage. Since an official time series of TBE vaccination coverage is only available for Austria, the missing TBE vaccination coverages of Germany and Switzerland were reconstructed and presented as the first results. Model verification results in explained variances of 76% for Austria, 84% for Germany, and 89% for Switzerland. Thus, the best model fit was determined for the Swiss GLM which is able to predict the TBE incidence with a root-mean-square error of RMSE = 25 cases (19% of the mean TBE incidence 1991-2018 or 7% of the TBE incidence of 2018). Forecasting TBE incidences for 2019 and 2020 results in 92 ±â€¯12 and 142 ±â€¯26 TBE cases for Austria, 417 ±â€¯71 and 670 ±â€¯168 TBE cases for Germany as well as 235 ±â€¯30 and 465 ±â€¯91 TBE cases for Switzerland.


Assuntos
Encefalite Transmitida por Carrapatos/epidemiologia , Áustria/epidemiologia , Encefalite Transmitida por Carrapatos/virologia , Alemanha/epidemiologia , Incidência , Modelos Teóricos , Suíça/epidemiologia
8.
BMC Infect Dis ; 20(1): 448, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32586360

RESUMO

BACKGROUND: Why human tick-borne encephalitis (TBE) cases differ from year to year, in some years more 100%, has not been clarified, yet. The cause of the increasing or decreasing trends is also controversial. Austria is the only country in Europe where a 40-year TBE time series and an official vaccine coverage time series are available to investigate these open questions. METHODS: A series of generalized linear models (GLMs) has been developed to identify demographic and environmental factors associated with the trend and the oscillations of the TBE time series. Both the observed and the predicted TBE time series were subjected to spectral analysis. The resulting power spectra indicate which predictors are responsible for the trend, the high-frequency and the low-frequency oscillations, and with which explained variance they contribute to the TBE oscillations. RESULTS: The increasing trend can be associated with the demography of the increasing human population. The responsible GLM explains 12% of the variance of the TBE time series. The low-frequency oscillations (10 years) are associated with the decadal changes of the large-scale climate in Central Europe. These are well described by the so-called Scandinavian index. This 10-year oscillation cycle is reinforced by the socio-economic predictor net migration. Considering the net migration and the Scandinavian index increases the explained variance of the GLM to 44%. The high-frequency oscillations (2-3 years) are associated with fluctuations of the natural TBE transmission cycle between small mammals and ticks, which are driven by beech fructification. Considering also fructification 2 years prior explains 64% of the variance of the TBE time series. Additionally, annual sunshine duration as predictor for the human outdoor activity increases the explained variance to 70%. CONCLUSIONS: The GLMs presented here provide the basis for annual TBE forecasts, which were mainly determined by beech fructification. A total of 3 of the 5 years with full fructification, resulting in high TBE case numbers 2 years later, occurred after 2010. The effects of climate change are therefore not visible through a direct correlation of the TBE cases with rising temperatures, but indirectly via the increased frequency of mast seeding.


Assuntos
Encefalite Transmitida por Carrapatos/epidemiologia , Animais , Áustria , Mudança Climática , Emigração e Imigração , Encefalite Transmitida por Carrapatos/etiologia , Encefalite Transmitida por Carrapatos/transmissão , Humanos , Incidência , Modelos Estatísticos , Fatores de Tempo
9.
Rev. biol. trop ; 67(2)abr. 2019.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1507489

RESUMO

Los estudios fenológicos generan información que contribuye con el conocimiento de las relaciones entre especies y componentes abióticos de los ecosistemas, disponibilidad de alimento para animales y regeneración de cobertura boscosa. Crescentia alata es una especie arbórea abundante en el bosque tropical seco (BTs); su importancia ecológica, cultural y económica ha sido ampliamente reconocida y por eso existe interés en reproducir esta especie, pero antes es necesario conocer detalladamente su desarrollo fenológico. El objetivo de este estudio fue describir la fenología de C. alata en el BTs de Costa Rica. Se seleccionaron 20 árboles reproductivos en el Parque Nacional Santa Rosa para observar las siguientes fenofases: follaje, floración y fructificación por 14 meses entre 2015 y 2016. Esta especie produjo más follaje en junio, máxima floración en junio y octubre y mayor número de frutos maduros en enero. Los patrones fenológicos en C. alata se relacionaron con factores climáticos comunes, sobre todo precipitación, temperatura y humedad relativa. Los resultados más relevantes de este estudio podrían contribuir a la propagación, el manejo adecuado y la conservación de esta especie.


Phenological studies generate information that contributes knowledge on relationships of species and abiotic components of ecosystems, availability of food for animals and regeneration of forest cover. Crescentia alata is an abundant tree species in tropical dry forests; its ecological, cultural and economic importance has been widely recognized and for this reason there is an interest in reproducing this species, but previously it is necessary to understand its detailed phenological development. The aim of this work was to describe C. alata phenology in dry Costa Rican forests. Twenty reproductive trees were selected at the Santa Rosa National Park to observe phenophases (leaf flushing, flower production, and fructification) during 14 months from 2015 to 2016. Most foliage was observed in June, maximal floration in June and October, and the highest ripe-fruit number in January. Phenological patterns in C. alata were related to common climatic factors as rainfall, temperature, and relative humidity; other factors considered were wind speed, and sun radiation. The most significant phenological data registered for C. alata in this work may contribute to a better management and conservation of this species.

10.
Exp Appl Acarol ; 75(3): 281-288, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29846854

RESUMO

The castor bean tick, Ixodes ricinus (L.) (Ixodida: Ixodidae), is the principal vector of pathogens causing tick-borne encephalitis or Lyme borreliosis in Europe. It is therefore of general interest to make an estimate of the density of I. ricinus for the whole year at the beginning of the tick season. There are two necessary conditions for making a successful prediction: a long homogeneous time series of observed tick density and a clear biological relationship between environmental predictors and tick density. A 9-year time series covering the period 2009-2017 of nymphal I. ricinus flagged at monthly intervals in southern Germany has been used. With the hypothesis that I. ricinus density is triggered by the fructification of the European beech 2 years before, the mean annual temperature of the previous year, and the current mean winter temperature (December-February), a forecast of the annual nymphal tick density has been made. Therefore, a Poisson regression model was generated resulting in an explained variance of 93.4% and an error of [Formula: see text] ticks per [Formula: see text] (annual [Formula: see text] collected ticks/[Formula: see text]). An independent verification of the forecast for the year 2017 resulted in 187 predicted versus 180 observed nymphs per [Formula: see text]. For the year 2018 a relatively high number of 443 questing I. ricinus nymphs per [Formula: see text] is forecasted, i.e., a "good" tick year.


Assuntos
Ixodes/fisiologia , Animais , Alemanha , Densidade Demográfica , Previsões Demográficas , Reprodução , Estações do Ano
11.
Sci Total Environ ; 599-600: 637-646, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28494288

RESUMO

Understanding the effects of nitrogen deposition, ozone and climate on tree growth is important for planning sustainable forest management also in the future. The complex interplay of all these factors cannot be covered by experiments. Here we use observational data of mature forests for studying associations of various biotic and abiotic factors with tree growth. A 30year time series on basal area increment of Fagus sylvatica L. and Picea abies Karst. in Switzerland was analyzed to evaluate the development in relation to a variety of predictors. Basal area increment of Fagus sylvatica has clearly decreased during the observation period. For Picea abies no trend was observed. N deposition of more than 26 (beech) or 20-22kgNha-1year-1 (Norway spruce) was negatively related with basal area increment, in beech stronger than in Norway spruce. High N deposition loads and low foliar K concentrations in Fagus were correlated with increased drought sensitivity. High air temperatures in winter were negatively related with basal area increment in Norway spruce in general and in beech at high N:Mg ratio or high N deposition while on an average the relation was positive in beech. Fructification in beech was negatively related to basal area increment. The increase of fructification observed during the last decades contributed thus to the growth decrease. Ozone flux was significantly and negatively correlated with basal area increment both in beech and Norway spruce. The results show clear non-linear effects of N deposition on stem increment of European beech and Norway spruce as well as strong interactions with climate which have contributed to the growth decrease in beech and may get more important in future. The results not only give suggestions for ecological processes but also show the potential of an integral evaluation of observational data.

12.
Ecology ; 98(5): 1473, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28241388

RESUMO

Tree masting is one of the most intensively studied ecological processes. It affects nutrient fluxes of trees, regeneration dynamics in forests, animal population densities, and ultimately influences ecosystem services. Despite a large volume of research focused on masting, its evolutionary ecology, spatial and temporal variability, and environmental drivers are still matter of debate. Understanding the proximate and ultimate causes of masting at broad spatial and temporal scales will enable us to predict tree reproductive strategies and their response to changing environment. Here we provide broad spatial (distribution range-wide) and temporal (century) masting data for the two main masting tree species in Europe, European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) H. Karst.). We collected masting data from a total of 359 sources through an extensive literature review and from unpublished surveys. The data set has a total of 1,747 series and 18,348 yearly observations from 28 countries and covering a time span of years 1677-2016 and 1791-2016 for beech and spruce, respectively. For each record, the following information is available: identification code; species; year of observation; proxy of masting (flower, pollen, fruit, seed, dendrochronological reconstructions); statistical data type (ordinal, continuous); data value; unit of measurement (only in case of continuous data); geographical location (country, Nomenclature of Units for Territorial Statistics NUTS-1 level, municipality, coordinates); first and last record year and related length; type of data source (field survey, peer reviewed scientific literature, gray literature, personal observation); source identification code; date when data were added to the database; comments. To provide a ready-to-use masting index we harmonized ordinal data into five classes. Furthermore, we computed an additional field where continuous series with length >4 yr where converted into a five classes ordinal index. To our knowledge, this is the most comprehensive published database on species-specific masting behavior. It is useful to study spatial and temporal patterns of masting and its proximate and ultimate causes, to refine studies based on tree-ring chronologies, to understand dynamics of animal species and pests vectored by these animals affecting human health, and it may serve as calibration-validation data for dynamic forest models.


Assuntos
Fagus/fisiologia , Picea/fisiologia , Europa (Continente) , Florestas , Noruega , Árvores
13.
Hist Philos Life Sci ; 38(3): 10, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27412708

RESUMO

In Philosophia Botanica (1751), Carolus Linnaeus (1707-1778) presented a calculation of the number of plant genera that may be distinguished based on his taxonomic concepts. In order to derive that number, he relied upon the organs of fructification, which represent the flower and the fruit, by selecting over 30 elements from them, and then assuming that each could vary by four dimensions. However, while Linnaeus was good in counting stamens and pistils, he and many of his followers who edited or translated Philosophia Botanica were less careful, basing their calculations of the number of possible genera on flawed assumptions, or even introducing basic arithmetic errors. Furthermore, although mathematics was quite advanced in the eighteenth century, the gap between combinatorial and botanical thinking was too deep, preventing Linnaeus to seek a reasonable solution to the problem he raised. The authors demonstrate this by a historical analysis of 15 editions of Philosophia Botanica, plus many references to it, and conclude that the desired number almost always appeared in error during the past 265 years. The German botanist J. G. Gleditsch (1714-1786) was the most successful with respect to Linnaeus' original intention. Elementary mathematics demonstrates that if Linnaeus' assumptions were taken seriously, then the possible number of genera would be astronomical. The practice he followed in Genera Plantarum (1754) shows, however, that the fructification dimensions served as a universal set for Linnaeus from which he chose only the relevant ones for describing a particular genus empirically. Based on the corrections and modifications implemented in reworked editions, we suggest an evolutionary network for the historical and modern versions or translations of Philosophia Botanica.


Assuntos
Botânica/história , História Natural/história , História do Século XVIII , Conceitos Matemáticos , Filosofia , Suécia
14.
Breed Sci ; 66(3): 391-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27436949

RESUMO

Amomum tsaoko is a flexistylous ginger. Flexistyly is a unique floral mechanism promoting outcrossing, which is known only in some species of Zingiberaceae till date. This is a pioneer report on flexistyly in A. tsaoko from the aspect of fructification percentage to clarify its influence on reproduction. We observed in 2007 and 2008 that the fructification percentage of the anaflexistyled and the cataflexistyled inflorescence were 14.89 ± 10.35% and 11.31 ± 7.91% respectively, with significant difference (d.f. = 141.920, t = 2.518, P = 0.013 < 0.05). The greatly significant difference between 2007 and 2008 were present in both the flower number (d.f. = 93, t = -2.819, P = 0.006 < 0.01) and the fructification percentage (d.f. = 93, t = -2.894, P = 0.005 < 0.01) of the cataflexistylous inflorescence. Although the two morphs were similar in morphological characteristics, there was some gender differentiation between them, showing a possibility that the anaflexistylous morph might function more as females and the cataflexistylous morph more as males. Reproduction of the cataflexistylous morph was significantly sensitive to change of environmental factors, in contrast to the anaflexistylous morph, thus the yield varied between the abundant year (2008) and the off year (2007).

15.
Zoonoses Public Health ; 63(2): 83-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26177110

RESUMO

Bank voles can harbour Puumala virus (PUUV) and vole populations usually peak in years after beech mast. A beech mast occurred in 2014 and a predictive model indicates high vole abundance in 2015. This pattern is similar to the years 2009/2011 when beech mast occurred, bank voles multiplied and human PUUV infections increased a year later. Given similar environmental conditions in 2014/2015, increased risk of human PUUV infections in 2015 is likely. Risk management measures are recommended.


Assuntos
Arvicolinae/virologia , Surtos de Doenças , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/transmissão , Virus Puumala , Animais , Demografia , Ecossistema , Fagus , Alemanha/epidemiologia , Orthohantavírus , Infecções por Hantavirus , Humanos , Virus Puumala/isolamento & purificação , Fatores de Risco , Tempo (Meteorologia)
16.
J Exp Bot ; 67(1): 365-77, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26512057

RESUMO

In soybean, long days during post-flowering increase seed number. This positive photoperiodic effect on seed number has been previously associated with increments in the amount of radiation accumulated during the crop cycle because long days extend the duration of the crop cycle. However, evidence of intra-nodal processes independent of the availability of assimilates suggests that photoperiodic effects at the node level might also contribute to pod set. This work aims to identify the main mechanisms responsible for the increase in pod number per node in response to long days; including the dynamics of flowering, pod development, growth and set at the node level. Long days increased pods per node on the main stems, by increasing pods on lateral racemes (usually dominated positions) at some main stem nodes. Long days lengthened the flowering period and thereby increased the number of opened flowers on lateral racemes. The flowering period was prolonged under long days because effective seed filling was delayed on primary racemes (dominant positions). Long days also delayed the development of flowers into pods with filling seeds, delaying the initiation of pod elongation without modifying pod elongation rate. The embryo development matched the external pod length irrespective of the pod's chronological age. These results suggest that long days during post-flowering enhance pod number per node through a relief of the competition between pods of different hierarchy within the node. The photoperiodic effect on the development of dominant pods, delaying their elongation and therefore postponing their active growth, extends flowering and allows pod set at positions that are usually dominated.


Assuntos
Glycine max/crescimento & desenvolvimento , Fotoperíodo , Luz Solar , Frutas/crescimento & desenvolvimento , Frutas/efeitos da radiação , Reprodução , Sementes/crescimento & desenvolvimento , Sementes/efeitos da radiação , Glycine max/efeitos da radiação
17.
Ecotoxicol Environ Saf ; 125: 184-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26706395

RESUMO

The cultivation and fructification of 15 saprotrophic and wood-rotting fungal strains were tested on three various semi-natural medium. The formation of fruit bodies was observed for Panellus stipticus, Psilocybe cubensis, Schizophyllum commune and Stropharia rugosoannulata in the frame of 1-2 months. Mercury translocation from the substrate to the fruit bodies was then followed in oat flakes medium. Translocation was followed for treatments of 0, 1.25, 2.5, 5, 10 and 20ppm Hg in the substrate. All four fungi formed fruit bodies in almost all replicates. The fruit body yield varied from 0.5 to 15.3g dry weight. The highest bioconcentration factor (BCF) of 2.99 was found for P. cubensis at 1.25ppm Hg. The BCF decreased with increasing Hg concentration in the substrate: 2.49, 0, 2.38, 1.71 and 1.82 for P. stipticus; 3.00, 2.78, 2.48, 1.81 and 2.15 for P. cubensis; 2.47, 1.81, 1.78, 1.07 and 0.96 for S. commune; and 1.96, 1.84, 1.21, 1.71 and 0.96 for S. rugosoannulata. The Hg contents in the fruit bodies reflected the Hg contents in the substrate; the highest contents in the fruit bodies were found in P. cubensis (43.08±7.36ppm Hg) and P. stipticus (36.42±3.39ppm).


Assuntos
Agaricales/química , Avena/química , Carpóforos/química , Mercúrio/análise , Psilocybe/química , Schizophyllum/química , Agaricales/classificação , Meios de Cultura/química , Psilocybe/classificação , Schizophyllum/classificação
18.
Rev. cient. (Guatem.) ; 25(2): 59-74, Noviembre 2015.
Artigo em Espanhol | LILACS | ID: biblio-884082

RESUMO

Los hongos del género Marasmius Fr. son i mportantes degradadores de hojarasca y se reportan como los más abundantes en los trópicos. La Ecorregión Lachuá es uno de los remanentes más importantes de selvas tropicales en Guatemala, y de los más amenazados por la pérdida de hábitat debido al avance de la frontera agrícola. Se ha determinado que durante los últimos 5 años se ha perdido el 75% de cobertura original fuera de las áreas protegidas de la ecorregión, debido principalmente al aumento de la agricultura. Estos cambios ocasionados por la pérdida de cobertura vegetal influyen en las condiciones microclimáticas de las cuales los hongos dependen para poder reproducirse. Este estudio constituye el primer acercamiento para comprender como responde este grupo de hongos a las fluctuaciones causadas por el cambio en condiciones climáticas y su vulnerabilidad a la pérdida de hábitat. Se evaluó la producción de cuerpos fructíferos del género Marasmius en respuesta a los factores climáticos temperatura, humedad relativa, precipitación, temporalidad y tamaño de remanente en la en época de lluvias durante 2010 y 2011 en ocho remanentes boscosos en la Ecorregión Lachuá. Se recolectaron 98 ejemplares pertenecientes a 56 morfoespecies y 2 especies. Las mayores riquezas (r) y frecuencias acumuladas (a) de cuerpos fructíferos se presentaron en junio (r=16, a=21) y en la localidad de Santa Lucía Lachuá (r =15, a=16). Los rangos de las variables climáticas donde se presentó mayor frecuencia acumulada fue T°= 26°C­27°C; Precipitación= 8­12 mm y 40mm y H%= 88­90%. La composición de Marasmius está influenciada por la temporalidad que de junio a agosto presenta mayor número de especies compartidas, disminuyéndose considerablemente en octubre y noviembre. No se observó un cambio en la composición de Marasmius en relación al tamaño de remanente, sin embargo espacialmente es posible diferenciar entre remanentes rodeados por áreas con cobertura y remanentes rodeados por áreas abiertas, determinando que este género responde a los cambios de hábitat. Estos cambios en riqueza y abundancia acumulada de hongos en el tiempo y el espacio, pueden ser utilizados como indicadores de estas perturbaciones. La información generada permite proponer el monitoreo de este género a través del tiempo p ara generar planes de manejo adecuados para el área


Fungi of genus Marasmius Fr. are important litter decomposers and reported as abundant in tropics. Lachuá Ecoregion is the largest remaining tropical forests in Guatemala, and the most threatened by habitat loss due to the agricultural advance. It has been determined that over the past five years 75% of the original coverage outside protected areas in the ecoregion has been lost. This loss is mainly attributed to increased agriculture activity. These changes caused by the loss of plant cover influence the microclimatic conditions that depend on fungi to reproduce. This study is the first approach to understand how this group of fungi respond to currency fluctuations caused by changes in climatic conditions and vulnerability to habitat loss. Relationship of temperature, relative humidity, precipitation, temporality and patch size with Marasmius fruit bodies production were evaluated. The study was carried out in eight forest patches in the rainy season in 2010 and 2011 in Lachuá Ecoregion. 98 specimens of 56 morphospecies and 2 species were colected. The highest cumulative richness (r) and cumulative frequency (a) of fruit bodies were presented in June (r =16, a = 21) and Santa Lucia Lachuá locality (r =15, a = 16). Marasmius composition is influenced by temporality. June to August were the months with higher number of shared species, decreasing considerably in October and November. No change was observed in Marasmius composition allied to patch size, however spatially there is a difference between patches surrounded by coverage areas and patches surrounded by open areas. This shows that genera responds to changes in habitat. These changes in cumulative richness and abundance of fungi over time and space, can be used as disturbance indicators. This information allows proposed monitoring of this genera over time to produce a management plan for the area


Assuntos
Humanos , Marasmius , Fungos/classificação , Mudança Climática
19.
Can J Microbiol ; 61(6): 447-50, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25803209

RESUMO

Tricholoma matsutake is an ectomycorrhizal fungus that dominates the microbial communities in the soil of pine and spruce forests. The mycorrhizas of this fungus have antimicrobial activity, although factors responsible for the antimicrobial activity have not been fully elucidated. The present study shows that fruit bodies of T. matsutake secreted hydrogen peroxide (H2O2), which was produced by pyranose oxidase, and that the H2O2 thus secreted strongly inhibited the growth of mycelia of the phytopathological fungus Rhizoctonia solani. These findings suggest that fruit bodies of T. matsutake have antifungal activity and that the pyranose oxidase plays an important role in the antifungal activity.


Assuntos
Carpóforos/química , Peróxido de Hidrogênio/metabolismo , Rhizoctonia/crescimento & desenvolvimento , Tricholoma/metabolismo , Desidrogenases de Carboidrato/metabolismo , Carpóforos/enzimologia , Carpóforos/crescimento & desenvolvimento , Carpóforos/metabolismo , Proteínas Fúngicas/metabolismo , Peróxido de Hidrogênio/farmacologia , Micélio/química , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Pinus/microbiologia , Rhizoctonia/efeitos dos fármacos , Tricholoma/química , Tricholoma/enzimologia , Tricholoma/crescimento & desenvolvimento
20.
Fungal Genet Biol ; 73: 1-11, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25234739

RESUMO

The button mushroom Agaricus bisporus is cultivated almost worldwide. Its cultivation is standardized and a temperature of 16-19 °C is needed during the fruiting period. The development of A. bisporus cultivars able to fruit at higher temperature (FHT) represents a promising alternative to reduce energy costs during cultivation in hot countries as well as in temperate countries during the hot season. A. bisporus var. burnettii is able to fruit at 25 °C. Understanding the biological mechanisms that underlie such a thermo-tolerance is a prerequisite to further development of breeding strains. The foundation of the FHT ability of the var. burnettii was dissected using a combination of candidate gene approaches and genetic tools. Transcript profiling of A. bisporus var. burnettii at two developmental stages (primordium P and sporophore SP) under two fruit-producing temperature conditions (17 °C and 25 °C) were established by cDNA-AFLP. The expression patterns were more similar within the same stage at the two different temperatures rather than between stages under the same temperature. Only one transcript-derived fragment (TDF) sequence differentially expressed between temperatures was recovered but it could not be further characterized. Twenty-nine TDF sequences differentially expressed between development stages were obtained. The phenotypic assessment of an intervarietal A. bisporus var. bisporus×A. bisporus var. burnettii progeny demonstrated the complex inheritance of the FHT trait. Two quantitative trait loci (QTL) involved in the number of fruit bodies yielded at 25 °C were found on LG II and LG VI. Two functional candidate genes known to be potentially involved in A. bisporus thermo-tolerance, a heat shock protein (HSP70) gene and a gene coding for a para-aminobenzoic acid synthase (PABA), were found in the vicinity of the QTL on LG II. Several positional candidate genes have been also identified in the confidence interval of the QTL on LG VI and are promising for further fine mapping purpose.


Assuntos
Agaricus/fisiologia , Proteínas Fúngicas/fisiologia , Temperatura Alta , Agaricus/genética , DNA Fúngico/genética , Perfilação da Expressão Gênica , Locos de Características Quantitativas
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