Rhynchosporium consists of two species, R. secalis and R. orthosporum. Both are pathogens of grasses with R. secalis infecting a variety of Poaceae hosts and R. orthosporum infecting Dactylis glomerata. Phylogenetic analyses of multilocus DNA sequence data on R. secalis isolates originating from cultivated barley, rye, triticale and other grasses, including Agropyron spp., Bromus diandrus and H...

Within the oak woodlands of California there is often a distinct shift in the botanical composition between the open grassland and the herbaceous understory beneath oak canopy. Botanical sampling at two woodland sites indicated that the annual grass Bromus diandrus was dominant under deciduous blue oak canopy, while a congener, Bromus hordeaceus, was dominant in open grassland. We examined the ...

negatively affected by disturbance. meadow barley (Hordeum brachyantherum Nevski) (Hickman 1993). Purple needlegrass, blue wildrye, bluegrass and California melic are droughttolerant species that typically occupy well-drained upland sites. In contrast, creeping wildrye and meadow barley are less drought-tolerant and typically grow in the moist soils of seeps, streams and wetland margins (Walker...

49 Early emergence of plant seedlings can offer strong competitive advantages over 50 later-germinating neighbors through the preemption of limiting resources. This 51 phenomenon may have contributed to the persistent dominance of European annual 52 grasses over native perennial grasses in California grasslands, since the former 53 species typically germinate earlier in the growing season than ...

El objetivo de este estudio fue evaluar tres pastos forrajeros, Bromus diandrus, Oplismenus burmannii y Heteropogon contortus, las subfamilias Pooideae, Pooideae Panicoideae, respectivamente. Las principales variables respuesta, todas en base seca fueron: cenizas (Cen), proteína cruda (PC), extracto etéreo (EE), carbohidratos solubles (CS), fibra detergente neutro (FDN), contenido celular (CC =...

Generalist plant pathogens may have wide host ranges, but many exhibit varying degrees of host specialization, with multiple pathogen races that have narrower host ranges. These races are often genetically distinct, with each race causing highest disease incidence on its host of origin. We examined host specialization in the seed pathogen Pyrenophora semeniperda by reciprocally inoculating path...