Bromus catharticus in South America (Poaceae: Bromeae)

Abstract

Although the venation characteristic of the lem¬ ma appears to he useful in separating B. catharticus var. rupestris from variety catharticus it is often (usually) very difficult to see even under 20X mag¬ nification. Other specimens, such as Kurtz 10034 (CORD) from Puesto Lima, Mendoza, have a few spikelets with additional bracts below the glumes that are 1â€"3-nerved. Another specimen (Kurtz 5668, CORD), from the Rio Atuel, Mendoza, has a few spikelets with an additional 5-nerved bract at the base. Besides these few aberrant characteris¬ tics, all other characteristics seem to be consistent with those described for this variety.

Regional variation in Argentinean populations of <i>Bromus catharticus</i> (Poaceae) as measured by morphological

“…These authors also found overlapping variation among infraspecific discontinuities (subspecies) based on only one quantitative trait, the length of lemmatal awn. However, infraespecific differentiation was easily recognized when DNA fragments and other qualitative attributes were used (Massa & al., 2001, Peterson & Planchuelo, 1998. Although the lemmatal awns showed non-significant differences between groups, the range of variation of this traits encountered in this study was similar to that described by Massa & al.…”

“…Previous systematic studies of the B. catharticus complex showed controversial results (Peterson & Planchuelo, 1998;Massa & al., 2004). These authors also found overlapping variation among infraspecific discontinuities (subspecies) based on only one quantitative trait, the length of lemmatal awn.…”

“…Massa. In a previous paper, Peterson & Planchuelo (1998) In Argentina, B catharticus (syn. B. willdenowii Kunth, B. unioloides Kunth) 'rescue grass' or 'prairie grass' is widely distributed in the Pampas (Burkart, 1969).…”

Phenotypic diversity in Argentinian populations ofBromus catharticus(Poaceae). Genetic and environmental components of quantitative traits

“…The lemma and its awn have been repeatedly used in taxonomic studies oîBromus and have usually been used for intrageneric classification by various authors (Raven 1960;Melderis 1968;Maw 1974;Hill & Kirby 1985;Planchuelo 1991;Gutiérrez & Pensiero 1998;Peterson & Planchuelo 1998;Kosina 1999). The present results showed that lemma awn length (LAL) and nervation number in the lemma (NNL) differentiated populations significantly, but they were not classified in the group of variables with a higher constancy ratio because of their high environmental variation.…”

Pollen viability and meiotic abnormalities in brome grasses(Bromus L., Section Ceratochloa) from Argentina

“…The complex was originally subdivided into a number of species, but after further investigations using morphological and/or molecular markers, many species were grouped into a hypervariable one (Planchuelo, 1991(Planchuelo, , 2006Peterson and Planchuelo, 1998;Massa, 2004;Williams et al, 2011). In this regard, Williams et al (2011, p. 24) pointed out that "Hybridization is rife in this section, making species boundaries obscure and the taxonomy very difficult".…”