Submitted to: Abstract of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: July 20, 2001
Publication Date: October 21, 2001
Technical Abstract: Although several factors influence stand establishment from seed, drought is by far the most common cause of establishment failure. An experiment was conducted to determine the effects of simulated dry conditions and seed processing on the germination and seedling growth of five warm-season grasses ('Aldous' little bluestem, 'Osage' indiangrass, 'Rountree' big bluestem, 'Woodward' sand bluestem, and 'WW-Spar' Old World bluestem). Seed of each cultivar was processed to 98% pure seed of rough (chaffy) intact spikelets, debearded-rough spikelets lightly trimmed of hair and awns with a rub-board, and caryopses processed with the Woodward laboratory air-seed shucker. Processed pure seed of each cultivar were germinated at five water potentials ( -1.6, -0.8, -0.4, -0.2, and 0 MPa ) in an environment set for 8 h light at 30 C and 16 h dark at 20 C. These initial results showed that cumulative 7-, 14-, 21-d seed germination, and firm seed remaining at the end of 21 d germination period was characterized by Cultivar (C) x Seed Processing (SP) x Water Potential (WP) interactions (P < 0.01). Total potential germination (21-d cumulative + firm seed remaining) was explained by C x SP interactions and WP main effects. Root length, measured at the 7-d germination count, was defined by C x SP x WP interactions and shoot length was described by C x SP and C x WP interactions. Understanding the germination and seedling growth of these species grown at negative water potentials may lead to better cultivars with greater establish success.