A Hirsute Ecotype Isolated from Common Dallisgrass ( Paspalum dilatatum Poir) 1

DALLISGRASS has^een widely spread over much of the Southeastern states for more than 60 years and in Louisiana and adjoining states for over 100 years (5). Its origin is thought to be Uruguay and adjoining areas of Brazil and Argentina. It has been an important pasture grass in Australia since before 1900 (5). In spite of the wide dissemination of this species only three distinguishable types have been reported (3). One is erect with yellow anthers; a second type is semi-prostrate with purple anthers; and the third is common dallisgrass which is semi-erect with purple anthers. Common has enjoyed the widest distribution since it has been planted in pastures for more than fifty years (5). From studies of more than 100 dallisgrass ecotypes during the past 25 years, Burton (3) reported that most of them resembled common dallisgrass very closely and he was unable to distinguish morphological differences between any except the erect, yellow-arithered and prostrate types, both of which came from Uruguay. A limited germ plasm survey was made of common dallisgrass using sources of seed from natural stands in Louisiana and adjoining states (4). From this work two strains, B230 and 430 were isolated. These strains were significantly more fertile than common dallisgrass, but the increases were apparently not sufficient to make the new strains acceptable as substantial improvements in. seed production of this grass in the southern region. No seed of these are being produced commercially at the present time. Morphologically, the plants of these strains were not different from that of the parent.