Banana is the most popular and most exported fruit and also a major food crop for millions of people around the world. Despite its importance and the presence of serious disease threats, research ...into this crop is limited. One of those is Panama disease or Fusarium wilt. In the previous century Fusarium wilt wiped out the "Gros Michel" based banana industry in Central America. The epidemic was eventually quenched by planting "Cavendish" bananas. However, 50 years ago the disease recurred, but now on "Cavendish" bananas. Since then the disease has spread across South-East Asia, to the Middle-East and the Indian subcontinent and leaped into Africa. Here, we report the presence of
f.sp.
Tropical Race 4 (Foc TR4) in "Cavendish" plantations in Laos, Myanmar, and Vietnam. A combination of classical morphology, DNA sequencing, and phenotyping assays revealed a very close relationship between the Foc TR4 strains in the entire Greater Mekong Subregion (GMS), which is increasingly prone to intensive banana production. Analyses of single-nucleotide polymorphisms enabled us to initiate a phylogeography of Foc TR4 across three geographical areas-GMS, Indian subcontinent, and the Middle East revealing three distinct Foc TR4 sub-lineages. Collectively, our data place these new incursions in a broader agroecological context and underscore the need for awareness campaigns and the implementation of validated quarantine measures to prevent further international dissemination of Foc TR4.
Understanding the evolutionary dynamics of forest islands in the landscape can inform conservation strategies for peatland ecosystems in tropical mountains and specify how different elements interact ...in landscape formation. We studied a peatland ecosystem at the headwaters of the Preto River, on a plateau surface known as Chapadão do Couto, in the Rio Preto State Park (São Gonçalo do Rio Preto, MG) at an altitude of 1,600 m. We analyzed two forest islands with predominantly semideciduous seasonal forest, one entirely within the peatland and the other at the transition to mesic grassland. The purpose was to investigate variations in the amount and fractioning of litter in each forest fragment at different times of the year, to show responses of the forest to the different conditions of insertion in the peatland and how this affects the dynamics of functional balance of the ecosystem. Four sampling of litter were made within the forest islands (Jun./2018 to Feb./2019) by the aid of 1 m2 collectors made of shade cloth, at a height of 50 cm. We observed a dynamic of interactions with distinct patterns among the forest islands, and also verified variations in the litter with respect to intensity and quantity of deposition, dynamics of deciduousness, this more associated with soil moisture conditions than the temperature at the surface and other features of the soil organic matter
Resumo O estado do Espírito Santo apresenta grande variedade de ecossistemas num território relativamente pequeno. A exuberância de suas florestas vem despertando o interesse de muitos naturalistas e ...viajantes desde o século XIX, os quais deixaram registros valiosos dos primeiros anos da ocupação das "Areas Prohibidas" a leste de Minas Gerais. O cultivo do café, um dos alicerces econômicos do estado, deu início à perda dessas florestas. Tais perdas alavancaram o movimento conservacionista e a pesquisa científica no estado. A biogeografia, riqueza de espécies e de processos ecológicos nos fragmentos que restaram no Espírito Santo ainda revelam surpresas. Dentro do domínio da Floresta Atlântica, o estado abriga diferentes tipos de vegetação: Floresta Ombrófila Densa, Floresta Ombrófila Aberta, Floresta Estacional Semidecidual, Savanas, Formações Pioneiras e Refúgios Ecológicos. A descrição e classificação da vegetação do Espírito Santo ainda está inacabada tendo em vista as incertezas levantadas por alguns estudos. Também não existe um mapa da vegetação que contemple adequadamente a diversificada vegetação. A despeito de tais limitações, apresentamos descrições sucintas sobre os tipos de vegetação que vêm sendo reconhecidos na literatura moderna.
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The Qinghai–Tibet Plateau has given birth to many indigenous highland plants due to its special geographical location and sensitivity to climate change. Relevantly, the impact of climate change on ...species distribution has been a hot issue for research in biogeography. Using the maximum entropy (MaxEnt) model, the spatial distribution of habitat suitability for Fritillaria przewalskii Maxim. (FPM) on the Tibetan Plateau was predicted and ranked by combining ecological data and information on its actual current geographical distribution. The potential distribution and trends of FPM on the Tibetan Plateau from 2021 to 2040, 2041 to 2060, 2061 to 2080 and 2081 to 2100 under four current and future climate scenarios (SSP126, SSP245, SSP370 and SSP585) were also predicted. The predictions were found to be highly accurate with AUC values of 0.9645 and 0.9345 for the training and test sets, respectively. A number of conclusions could be drawn from the results. Firstly, the main ecological factors limiting the growth distribution of FPM were the Vegetation types, NPP (net primary production), Soil types, Bio7 (temperature annual range), Pop (population), Slope, GDP, Aspect, Bio1 (annual mean temperature) and Elevation, with a cumulative contribution of 97.6%. Secondly, in the recent past period of 1970–2000, the total suitable distribution area of FPM accounted for 5.55% of the plateau’s total area, which was about 14.11 × 10sup.4 kmsup.2 , concentrated in its eastern and central regions. Thirdly, compared to the previous period, the aforementioned distribution area will, for the period spanning 2021–2040, increase by 14.48%, 16.23%, 16.99%, and 21.53% in the SSP126, SSP245, SSP370, and SSP585 scenarios, respectively. This comes with an overall expansion trend, and the areas predicted to be affected are concentrated in the eastern and central-western parts of the Tibetan Plateau. The other three future periods 2041–2060, 2061–2080, and 2081–2100 also show increases in these total areas to varying degrees. It is noteworthy that in the future periods 2061–2080 and 2081–2100, under the SSP370 and SSP585 scenarios, the area of high suitable distribution decreases or even disappears. Lastly, under the four climate scenarios, the FPM suitable distribution area will shift towards the western part of the Tibetan Plateau.
Harapan TS, Nurainas, Syamsuardi, Taufiq A. 2022. Identifying the potential geographic distribution for Castanopsis argentea and Castanopsis tungurrut (Family: Fagaceae) in the Sumatra Conservation ...Area Network, Indonesia. Biodiversitas 23: 1726-1733. Recently, Castanopsis argentea (Blume) A.DC. and Castanopsis tungurrut (Blume) A.DC. have been listed as endangered species by the International Union for the Conservation of Nature (IUCN). For conservation planning, it is important to know the full distribution of species. This study aimed to predict the potential distribution of C. argentea and C. tungurrut using MaxEnt, and understand key factors responsible for the distribution of these species. A total of 53 occurrences and six environmental variables were used to model their distribution. The AUC values of C. argentea and C. tungurrut were 0.86 and 0.91, respectively, and the models suggest the distribution of both species is mainly influenced by elevation, and temperature seasonality for C. tungurrut. The predicted distributions of the species are in the mountains of the western part of Sumatra, and their range includes 12 conservation areas that have highly suitable habitats for both species. After generating the MaxEnt prediction map, we conducted field validation to validate the model predictions. Field surveys in two predicted areas showed that the predicted distribution maps accurately estimated the distribution of C. argentea and C. tungurrut at those localities.
The identity of the dominant root-associated microbial symbionts in a forest determines the ability of trees to access limiting nutrients from atmospheric or soil pools
, sequester carbon
and ...withstand the effects of climate change
. Characterizing the global distribution of these symbioses and identifying the factors that control this distribution are thus integral to understanding the present and future functioning of forest ecosystems. Here we generate a spatially explicit global map of the symbiotic status of forests, using a database of over 1.1 million forest inventory plots that collectively contain over 28,000 tree species. Our analyses indicate that climate variables-in particular, climatically controlled variation in the rate of decomposition-are the primary drivers of the global distribution of major symbioses. We estimate that ectomycorrhizal trees, which represent only 2% of all plant species
, constitute approximately 60% of tree stems on Earth. Ectomycorrhizal symbiosis dominates forests in which seasonally cold and dry climates inhibit decomposition, and is the predominant form of symbiosis at high latitudes and elevation. By contrast, arbuscular mycorrhizal trees dominate in aseasonal, warm tropical forests, and occur with ectomycorrhizal trees in temperate biomes in which seasonally warm-and-wet climates enhance decomposition. Continental transitions between forests dominated by ectomycorrhizal or arbuscular mycorrhizal trees occur relatively abruptly along climate-driven decomposition gradients; these transitions are probably caused by positive feedback effects between plants and microorganisms. Symbiotic nitrogen fixers-which are insensitive to climatic controls on decomposition (compared with mycorrhizal fungi)-are most abundant in arid biomes with alkaline soils and high maximum temperatures. The climatically driven global symbiosis gradient that we document provides a spatially explicit quantitative understanding of microbial symbioses at the global scale, and demonstrates the critical role of microbial mutualisms in shaping the distribution of plant species.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Halimocnemis commixta is recorded as a new species for the flora of Iran from Pistacia vera woodland remnants in NE Iran. It grows on open salty soils with several typical halophytic plants. The new ...species record is illustrated and compared with the closely related species. It can be distinguished from H. gamocarpa by its clustered flowers and irregularly horned fruits and differs from H. pilosa by its entirely short and adpressed hairs. We provide some additional notes on the distribution, ecology, and conservation status of the newly recorded species.
On the southern periphery of Badzhal Mountain Range on, an area of about 25 sq. km, we found 313 species of mosses, listed here with distribution along with the altitudinal belts, ecotopes, and ...substrates. Among them, 73 species are newly recorded for the middle part of Khabarovsk Territory, and 39 of them are new to the whole Khabarovsk Territory, including rare species with no or few previously known records in Russia such as Campylopus gracilis, Sematophyllum substrumulosum, Anomodon solovjovii, Bryoerythrophyllum chenii, Dicranum setifolium, Ditrichum macrorhynchum, Haplohymenium longinerve, Okamurea hakkoniensis, Orthotrichum rogeri, Sphagnum miyabeanum, S. subnitens; identity of several species needs in specially focused taxonomic studies. Studied flora is compared with ones of Zeysky State Nature Reserve, Upper Bureya, and a combined list of mosses of Botchinsky Nature Reserve and Tordoki-Yani Mt. Among all these floras, the proportion of Eastern species in Badzhal is the highest. Main types of vegetation and bryophyte ecotopes are briefly characterized; distribution of species along an altitudinal gradient among considered types of habitats and substrates, is discussed.
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