Development and Testing of Cool-Season Grass Species, Varieties and Hybrids for Biomass Feedstock Production in Western North America

Breeding of native cool-season grasses has the potential to improve forage production and expand the range of bioenergy feedstocks throughout western North America. Basin wildrye (Leymus cinereus) and creeping wildrye (Leymus triticoides) rank among the tallest and most rhizomatous grasses of this region, respectively. The objectives of this study were to develop interspecific creeping wildrye (CWR) × basin wildrye (BWR) hybrids and evaluate their biomass yield relative to tetraploid ‘Trailhead’, octoploid ‘Magnar’ and interploidy-hybrid ‘Continental’ BWR cultivars in comparison with other perennial grasses across diverse single-harvest dryland range sites and a two-harvest irrigated production system. Two half-sib hybrid populations were produced by harvesting seed from the tetraploid self-incompatible Acc:641.T CWR genet, which was clonally propagated by rhizomes into isolated hybridization blocks with two tetraploid BWR pollen parents: Acc:636 and ‘Trailhead’. Full-sib hybrid seed was also produced from a controlled cross of tetraploid ‘Rio’ CWR and ‘Trailhead’ BWR plants. In space-planted range plots, the ‘Rio’ CWR × ‘Trailhead’ BWR and Acc:641.T CWR × Acc:636 BWR hybrids displayed high-parent heterosis with 75% and 36% yield advantages, respectively, but the Acc:641.T CWR × ‘Trailhead’ BWR hybrid yielded significantly less than its BWR high-parent in this evaluation. Half-sib CWR × BWR hybrids of Acc:636 and ‘Trailhead’ both yielded as good as or better than available BWR cultivars, with yields similar to switchgrass (Panicum virgatum), in the irrigated sward plots. These results elucidate opportunity to harness genetic variation among native grass species for the development of forage and bioenergy feedstocks in western North America

Com o diabo no corpo: os terríveis papagaios do Brasil colônia

Desde a Antiguidade, papagaios, periquitos e afins (Psittacidae) fascinaram os europeus por seu vivo colorido e uma notável capacidade de interação com seres humanos. A descoberta do Novo Mundo nada faria além de acrescentar novos elementos ao tráfico de animais exóticos há muito estabelecido pelos europeus com a África e o Oriente. Sem possuir grandes mamíferos, a América tropical participaria desse comércio com o que tinha de mais atrativo, essencialmente felinos, primatas e aves - em particular os papagaios, os quais eram embarcados em bom número. Contudo, a julgar pelos documentos do Brasil colônia, esses voláteis podiam inspirar muito pouca simpatia, pois nenhum outro animal - exceto as formigas - foi tantas vezes mencionado como praga para a agricultura. Além disso, alguns psitácidas mostravam-se tão loquazes que inspiravam a séria desconfiança de serem animais demoníacos ou possessos, pois só três classes de entidades - anjos, homens e demônios - possuíam o dom da palavra. Nos dias de hoje, vários representantes dos Psittacidae ainda constituem uma ameaça para a agricultura, enquanto os indivíduos muito faladores continuam despertando a suspeita de estarem possuídos pelo demônio. Transcendendo a mera curiosidade, essa crença exemplifica o quão intrincadas podem ser as relações do homem com o chamado “mundo natural”, revelando um universo mais amplo e multifacetado do que se poderia supor a princípio. Nesse sentido, a existência de aves capazes de falar torna essa relação ainda mais complexa e evidencia que as dificuldades de estabelecer o limite entre o animal e o humano se estendem além dos primatas e envolvem as mais inusitadas espécies zoológicas.Since ancient times, parrots and their allies (Psittacidae) have fascinated Europeans by their striking colors and notable ability to interact with human beings. The discovery of the New World added new species to the international exotic animal trade, which for many centuries had brought beasts to Europe from Africa and the Orient. Lacking large mammals, tropical America participated in this trade with its most appealing species, essentially felines, primates and birds - especially parrots - which were shipped in large numbers. It should be noted, however, that at times these birds were not well liked. In fact, according to documents from colonial Brazil, only the ants rank higher than parrots as the animals most often mentioned as agricultural pests. On the other hand, some of these birds were so chatty that people suspected them to be demonic or possessed animals, since only three classes of beings - angels, men and demons - have the ability to speak. Nowadays, several Psittacidae still constitute a threat to agriculture, and the suspicion that extremely talkative birds were demon possessed has also survived. More than a joke or a mere curiosity, this belief exemplifies how intricate man’s relationships with the “natural world” may be. In this sense, the existence of birds that are able to speak adds a further twist to these relationships, demonstrating that the problem of establishing a boundary between the animal and the human does not only involve primates, but also includes some unusual zoological species

Phylogenetic relationships among low ploidy Poa species using chloroplast sequences

Species in the Poa genus are taxonomically and genetically difficult to delineate due to high and variable polyploidy, aneuploidy, and challenging breeding systems. Approximately 5% of the proposed species in Poa are considered to include or comprise diploids, but very few of those diploids are represented in seed collections. Recent phylogenetic studies of Poa have included some diploid species to elucidate Poa genome relationships. In this study we build upon that foundation of diploid Poa relationships with additional confirmed diploid species and accessions, and with additional chloroplast sequences. We also include a sample from P. pratensis and P. arachnifera to hone in on possible ancestral genomes in these two agronomic and highly polyploidy species. Relative to most of the Poa species, Poa section Dioicopoa (P. ligularis, P. iridifolia, and P. arachnifera) contained relatively large chromosomes. Phylogenies were constructed using the TLF gene region and five additional chloroplast genes, and the placement of new species and accessions fit within chloroplast lineages reported in Soreng et al. (2010) better than by taxonomic subgenera and sections. Low ploidy species in the â Pâ chloroplast lineage, such as P. iberica and P. remota, grouped closest to P. pratensis.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author