Geographical structure, narrow species ranges, and Cenozoic diversification in a pantropical clade of epiphyllous leafy liverworts

The evolutionary history and classification of epiphyllous cryptogams are still poorly known. Leptolejeunea is a largely epiphyllous pantropical liverwort genus with about 25 species characterized by deeply bilobed underleaves, elliptic to narrowly obovate leaf lobes, the presence of ocelli, and vegetative reproduction by cladia. Sequences of three chloroplast regions (rbcL, trnL-F, psbA) and the nuclear ribosomal ITS region were obtained for 66 accessions of Leptolejeunea and six outgroup species to explore the phylogeny, divergence times, and ancestral areas of this genus. The phylogeny was estimated using maximum-likelihood and Bayesian inference approaches, and divergence times were estimated with a Bayesian relaxed clock method. Leptolejeunea likely originated in Asia or the Neotropics within a time interval from the Early Eocene to the Late Cretaceous (67.9 Ma, 95% highest posterior density [HPD]: 47.9-93.7). Diversification of the crown group initiated in the Eocene or early Oligocene (38.4 Ma, 95% HPD: 27.2-52.6). Most species clades were established in the Miocene. Leptolejeunea epiphylla and L. schiffneri originated in Asia and colonized African islands during the Plio-Pleistocene. Accessions of supposedly pantropical species are placed in different main clades. Several monophyletic morphospecies exhibit considerable sequence variation related to a geographical pattern. The clear geographic structure of the Leptolejeunea crown group points to evolutionary processes including rare long-distance dispersal and subsequent speciation. Leptolejeunea may have benefitted from the large-scale distribution of humid tropical angiosperm forests in the Eocene

Manual of tropical bryology

Bryophytes belong to the oldest land plants. They existed already in the Palaeozoic 300 mio years ago in forms which were hardly different from the extant species. They remained relatively unchanged with relatively low evolution rates (and are thus often called a „conservative“ plant group), but could successfully establish themselves in an always varying environment from Devonian swamps to Permian forests, Mesozoic deserts and as epiphytes in Tertiary rainforests. They are not eaten by snails or insects, and are resistant against fungi and bacteria

Genetic Analysis of Puccinia coronata Corda f.sp. avenae Resistance in Oat (Avena sativa L.)

In Western Canada, oat crown rust (caused by Puccinia coronata Corda f. sp. avenae Eriks) is considered the most economically important disease of cultivated oat (Avena sativa L.). Resistant oat varieties are an important control method for crown rust. Avena sterilis L. accessions have been the main source of crown rust resistance genes due to their reproductive compatibility with A. sativa. In order to discover new seedling resistance genes in Avena sterilis accessions, six genetic populations were generated by crossing AC Morgan (Reg. no.CV-369, PI 629113) with six A. sterilis accessions (PI311623-4, PI333561, PI334672-5, PI335562, PI375506 and PI375547). All F2 populations and partial F3 families were inoculated with isolate CR259 (race LQCB-91; virulent on Pc35/38/39/40/55/59/60/61/63/91) at the two leaf stage and rated 11 or 12 days post-inoculation. Resistance in PI334672-5 was the result of two resistance genes with one dominant resistance gene and one recessive resistance gene. Two dominant resistance genes were likely present in PI375547. Current F2 tests revealed that both PI311623-4 and PI335562 contained two dominant genes, resulting in duplicate dominant epistasis. Based on current F2 and F3 data, resistance genes present in PI375506 are most likely one dominant resistance gene or one dominant resistance gene and one recessive resistance gene. In F2 tests, PI333561 appeared to be heterogeneous. Assuming no heterogeneity, PI333561 would carry two resistance genes, one or both of which are incompletely dominant. PI333561 is the only accession resistant to all crown rust isolates contained in the Cereal and Flax Pathology Lab (University of Saskatchewan, Saskatoon, SK) and Cereal Research Centre (Agriculture and Agri-Food Canada, Winnipeg, MB) collections. As such, this accession likely carries valuable new seedling crown rust resistance genes. Extensive use of seedling genes in breeding programs corresponds with high virulence frequency to those genes. Adult plant resistance (APR) is believed to be a durable rust management strategy. The crown rust resistance in the oat line MN841801 has been effective for more than 20 years. Research was conducted to detect APR quantitative trait loci (QTLs) contributed by MN841801. A genetic map was generated in a population of 167 F7-derived recombinant inbred lines (RILs) from a cross AC Assiniboia x MN841801 (AM). The map containing mostly Diversity Arrays Technology (DArT) markers consisted of 30 linkage groups spanning 955 cM. Two field environmental tests under a lattice design were conducted in Saskatoon, Saskatchewan. Only one QTL contributed by AC Assiniboia was detected on 2010 Saskatchewan field data. This detected QTL was the result of the seedling resistance gene Pc68, since it was mapped 4 cM away from the sequence characterized amplified region (SCAR) marker Pc68-300. No QTL contributed by MN841801 were detected in this study. Low oat genome coverage in the current genetic map of the AM population is the primary limitation to detecting APR QTLs contributed by MN841801. Single nucleotide polymorphism (SNP) markers from the first complete oat map will be important for improving the genetic map of this population and detection of APR QTL from MN841801. Additional field testing of the AM population with P. coronata isolate CR251 is recommended to improve the precision and accuracy of the phenotypic data

Abstracts from the 25th Fungal Genetics Conference

Abstracts from the 25th Fungal Genetics Conferenc

Population genetics and phylogeny of the malesian palm genus Johannesteijsmannia H.E.Moore (Palmae)

Ph.DDOCTOR OF PHILOSOPH

Identification of Three Epichloë Endophytes from Hordeum bogdanii Wilensky in China

Cool season grasses often form reciprocal symbiotic relationships with endophytic fungal species in genus Epichloë. In this study, we characterized three fungal endophytes isolated from the grass Hordeum bogdanii native to northwest China. Based on morphological characteristics and phylogenetic analyses of tefA, tubB, and actG sequences, we identified them as Epichloë sp. HboTG-2 (H. bogdanii Taxonomic Group 2: E. bromicola × E. typhina). Alkaloid synthesis related genes analysis showed that Epichloë sp. HboTG-2 may have the ability only to produce peramine which is toxic to insects but not to animals. In the process of this study, we did not observe sexual structures or epiphyllous growth on leaves of infected plants

Molecular identification and characterization of endophytes from uncultivated barley

<p><i>Epichloë</i> species (Clavicipitaceae, Ascomycota) are endophytic symbionts of many cool-season grasses. Many interactions between <i>Epichloë</i> and their host grasses contribute to plant growth promotion, protection from many pathogens and insect pests, and tolerance to drought stress. Resistance to insect herbivores by endophytes associated with <i>Hordeum</i> species has been previously shown to vary depending on the endophyte-grass-insect combination. We explored the genetic and chemotypic diversity of endophytes present in wild <i>Hordeum</i> species. We analyzed seeds of <i>Hordeum bogdanii, H. brevisubulatum</i>, and <i>H. comosum</i> obtained from the US Department of Agriculture’s (USDA) National Plant Germplasm System (NPGS), of which some have been reported as endophyte-infected. Using polymerase chain reaction (PCR) with primers specific to <i>Epichloë</i> species, we were able to identify endophytes in seeds from 17 of the 56 Plant Introduction (PI) lines, of which only 9 lines yielded viable seed. Phylogenetic analyses of housekeeping, alkaloid biosynthesis, and mating type genes suggest that the endophytes of the infected PI lines separate into five taxa: <i>Epichloë bromicola, Epichloë tembladerae</i>, and three unnamed interspecific hybrid species. One PI line contained an endophyte that is considered a new taxonomic group, <i>Epichloë</i> sp. HboTG-3 (<i>H. bogdanii</i> Taxonomic Group 3). Phylogenetic analyses of the interspecific hybrid endophytes from <i>H. bogdanii</i> and <i>H. brevisubulatum</i> indicate that these taxa all have an <i>E. bromicola</i> allele but the second allele varies. We verified in planta alkaloid production from the five genotypes yielding viable seed. Morphological characteristics of the isolates from the viable <i>Hordeum</i> species were analyzed for their features in culture and in planta. In the latter, we observed epiphyllous growth and in some cases sporulation on leaves of infected plants.</p

Trail width and epiphyllous coverage of Chamaedorea spp

Epiphylls are bryophytes and lichens that grow on the leaves of other trees. These plants are dependent on water for survival and reproduction. Lichens are often used as bioindicators of climate change and pollution. The purpose of this study was to find out if trail width sufficiently changed the microclimate and altered epiphyll cover on trailside leaves. I hypothesized that epiphylls could be used as bioindicators of changing microclimate by trails from a control area. Liverwort and lichen cover were measured on leaves of Chamaedorea spp. (Arecaceae) in the Monteverde Biological Cloud Forest Preserve on five different trail types. Wider trails had decreased epiphyllous growth compared to narrower trails, with reductions of 82% to 89% on wide trails and 28% reductions on narrow trails. Epiphylls have shown that they can be used as bioindicators of small changes in sunlight due to trail widths. Epiphyll cover is declining linearly with trail widths. These effects can be warning signs for others plants that are harder to examine effects on. Las epífilas son briófitas y líquenes que crecen en las hojas de otros árboles. Estas plantas dependen del agua para su supervivencia y reproducción. Los líquenes son utilizados con frecuencia como bioindicadores de cambio climático y contaminación. El propósito de este estudio fue determinar si la amplitud de los senderos cambia el microclima y altera la cubierta de epífilas en las hojas a la orilla del sendero. Se propuso la hipótesis de que las epífilas briofíticas como los líquenes se podrían utilizar como bioindicadores de cambios en el microclima de los senderos en un área de control. Se determinó el porcentaje de cubierta de las hepáticas y líquenes en Chamaedorea spp. (Arecaceae) en la Reserva Biológica Bosque Nuboso de Monteverde, en cinco categorías diferentes de senderos. Se demostró que los senderos más anchos disminuyeron el crecimiento de epífilas más que los senderos más estrechos, con reducciones del 82% al 89% en senderos amplios. Se demostró que las epífilas pueden ser utilizadas como bioindicadores de cambios pequeños en la luz solar debido a la anchura del sendero.https://digitalcommons.usf.edu/tropical_ecology/1597/thumbnail.jp

Trail width and epiphyllous coverage of Chamaedorea spp

Epiphylls are bryophytes and lichens that grow on the leaves of other trees. These plants are dependent on water for survival and reproduction. Lichens are often used as bioindicators of climate change and pollution. The purpose of this study was to find out if trail width sufficiently changed the microclimate and altered epiphyll cover on trailside leaves. I hypothesized that epiphylls could be used as bioindicators of changing microclimate by trails from a control area. Liverwort and lichen cover were measured on leaves of Chamaedorea spp. (Arecaceae) in the Monteverde Biological Cloud Forest Preserve on five different trail types. Wider trails had decreased epiphyllous growth compared to narrower trails, with reductions of 82% to 89% on wide trails and 28% reductions on narrow trails. Epiphylls have shown that they can be used as bioindicators of small changes in sunlight due to trail widths. Epiphyll cover is declining linearly with trail widths. These effects can be warning signs for others plants that are harder to examine effects on. Las epífilas son briófitas y líquenes que crecen en las hojas de otros árboles. Estas plantas dependen del agua para su supervivencia y reproducción. Los líquenes son utilizados con frecuencia como bioindicadores de cambio climático y contaminación. El propósito de este estudio fue determinar si la amplitud de los senderos cambia el microclima y altera la cubierta de epífilas en las hojas a la orilla del sendero. Se propuso la hipótesis de que las epífilas briofíticas como los líquenes se podrían utilizar como bioindicadores de cambios en el microclima de los senderos en un área de control. Se determinó el porcentaje de cubierta de las hepáticas y líquenes en Chamaedorea spp. (Arecaceae) en la Reserva Biológica Bosque Nuboso de Monteverde, en cinco categorías diferentes de senderos. Se demostró que los senderos más anchos disminuyeron el crecimiento de epífilas más que los senderos más estrechos, con reducciones del 82% al 89% en senderos amplios. Se demostró que las epífilas pueden ser utilizadas como bioindicadores de cambios pequeños en la luz solar debido a la anchura del sendero.https://digitalcommons.usf.edu/tropical_ecology/1597/thumbnail.jp