Submitted to: Agronomy Society of America, Crop Science Society of America, Soil Science Society of America Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 10/1/2004
Publication Date: 11/1/2004
Citation: Rao, S.C., Northup, B.K. 2004. Grasspea-potential forage and grain for Southern Great Plains [abstract]. Agronomy Society of America, Crop Science Society of America, Soil Science Society of America Meeting. Paper No. 3545. Interpretive Summary: ABSTRACT ONLY
Technical Abstract: Grasspea (Latyrus sativa) is a drought-tolerant, cool-season grain legume from eastern Africa. Its adaptability to the southern Great Plains is unknown. This study evaluated forage and grain yield, yield distribution and nutritive values of grasspea grown in Oklahoma. Small plot studies were conducted in 2001 to 2003 on conventionally tilled soil. Seed of the cultivar 'AC Greenfix' was treated with 'Cell-Tech C' inoculant and seeded at 60 kg ha-1 in 60 cm spaced rows during mid-March. Whole plant samples were collected on five dates from 45 days after seeding (DAS) to 95 DAS. Herbage from the last two dates was separated into grain and non-grain portions. Samples were analyzed for nitrogen content and dry matter digestibility. Data were analyzed for year and date effects by repeated measures (all dates) and split plots in randomized designs (grain and non-grain). Date significantly (P<0.05) affected total dry matter, forage N and digestibility. Dry matter showed a cubic increase [6415 (±356) kg/ha at 75 DAS], forage N a cubic decrease [26.2 (±0.7) g/kg at 75 DAS) and digestibility a quadratic decrease (730 (±11) g/kg at 75 DAS). Year x date interactions in grain and non-grain yields were significant, as were year effects on seed digestibility (937 g/kg in 2003; 967±7 g/kg in 2001 and 2002). In 2002 and 2003, grain yield was higher 95 DAS (2023±98 kg/ha) than 75 DAS (1903±20 kg/ha). Results suggest grasspea could supply high quality herbage to partially fill the May forage gap that exists in existing wheat-based grazing systems.