Early Root and Shoot Elongation of Selected Warm-Season Perennial Grasses

Abstract

Root length and root:shoot ratios are considered to be important survival factors of seedlings growing in areas of limited water. This study was conducted to determine early root elongation and root:shoot ratios during the germination to seedling stage of 'Premier' sideoats grama [Bouteloua curtipendula (Michx.) Torr.], 'Cochise' lovegrass (Eragrostis lehmanniana Nees × Eragrostis trichophora Coss and Dur.), 'A-130' blue panic (Panicum antidotale Retz.), and accessions PMT-1733-77 and NM-184 alkali sacaton (Sporobolus airoides Torr.). Root and shoot measurements were made approximately every 12 hr from seed planting to 190 hr and the results related to species success or failure in reported seeding trials. Sideoats grama root lengths were greater than those of all other species at all sample times. Root lengths among the other species were not different until about 5 days after planting when Cochise lovegrass root lengths were significantly (P<0.05) less. Though there was no significant (P<0.05) difference in root lengths among accessions of alkali sacaton, accession 1733 root elongation continued after accession NM-184 root elongation ceased. Sideoats grama shoot lengths were significantly (P<0.05) greater than those of all species until day 6, when sideoats grama and blue panic were not different. Average 7-day root:shoot ratios ranged from 2.9:1 for sideoats grama to 1.3:1 for blue panic. Rapid root elongation or comparatively high root:shoot ratios obtained for species in this study could not be directly related to reported success or failure in seedling establishment.