|Mayeux Jr, Herman|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/15/2003
Publication Date: 11/1/2003
Citation: Rao, S.C., Phillips, W.A., Mayeux, H.S., Phatak, S.C. 2003. Potential grain and forage production of early maturing pigeonpeas in the Southern Plains. Crop Science. 43:2212-2217. Interpretive Summary: Forage-based livestock production is a significant component of the agricultural economy of the southern Great Plains. However, forage production is inadequate for efficient livestock production during the late summer, August through October, because the grasses and other forage plants which grow in the region are not productive and have low nutritive quality during those months. Two cultivars of a tropical legume, pigeonpea, were grown in Oklahoma to determine whether they have potential to provide high-quality forage during those months, or could be used to produce a pigeonpea grain crop. Both cultivars were genetically selected to flower and set seed early in the growing season. Both of them produced acceptable quantities of forage with high protein content late in the summer, relative to other forage plants. Grain yields varied with summer rainfall amounts, but were as high as 5,000 pounds per acre when drought conditions did not exist. These or similar pigeonpea cultivars can be grown in the region to fill the summer forage-deficit period. They also could be grown for production of grain, which can be used for human consumption or as a protein supplement for livestock.
Technical Abstract: Forage-based livestock production is a significant component of the agricultural economy throughout the southern Great Plains. However, low forage mass and quality for grazing limits livestock productivity from late-July to early-November. Pigeonpea (Cajanus cajan L. Millsp) is a warm-season grain legume that may have potential as a summer forage crop. A 3-yr (1996 to 1998) field study was conducted to assess forage and grain production and the nutritive value of two short-duration pigeonpea ecotypes, Georgia-2 and ICPL 85010. The two ecotypes did not differ significantly in forage and grain production and nutritive value. At 96 d after seeding, total aboveground biomass was 517 g m-2, N concentration was 23 g kg-1, and digestible dry-matter (DDM) was 580 g kg-1 averaged across years. At final harvest, 118 d after seeding, total aboveground biomass was 12.6, 6.4, and 9.3 Mg ha-1 in 1996, 1997, and 1998, respectively. Seed yield also varied with year, ranging from 5.4 Mg ha-1 in 1996 to 1.2 Mg ha-1 in 1998. Nitrogen concentration and DDM at final harvest was 19 and 585 g kg-1 for the total aboveground biomass, 34 and 758 g kg-1 for leaves, 9 and 420 g kg-1 for stems and 26 and 750 g kg-1 for seed, respectively. Short-duration pigeonpeas could fill the forage deficit period during late-summer and provide a high-protein grain for human consumption or a protein supplement for livestock.