Evidence against the existence of varieties in Arctagrostis latifolia ssp. arundinacea (Poaceae)

Abstract

The morphological diversity of North American specimens of Arctagrostis latifolia ssp. arundinacea (Trin.) Tzvelev was evaluated for possible varieties within the subspecies by considering (i) descriptions of three previously recognized taxa included in the subspecies, (ii) measurements of spikelet characters of the types of five taxa, (iii) Macoun's illustrations of spikelet diversity, (iv) a morphological study of 130 herbarium specimens, and (v) a transplant garden study. Characters thought to be uninfluenced by environment were examined. These included (i) the seed protein banding patterns revealed by SDS–PAGE, (ii) the guard cell sizes from plants of known chromosome number, and (iii) a study of anther lengths and pollen diameters. The data do not support the recognition of varieties. Key words: SDS–PAGE, transplant garden, pollen, chromosome number, guard cells, Arctagrostis, Poaceae, taxonomy.