Submitted to: Proceedings Assoc for Advancement of Industrial Crops (AAIC) Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 25, 2008
Publication Date: September 7, 2008
Citation: Wilson, J.P., Endale, D.M., Schomberg, H.H. 2008. Genotype and environmental effects on ethanol yield from pearl millet. Proceedings New Crops and Bioproducts Development. Assoc for Advancement of Industrial Crops. College Station, Texas. September 7-11, 2008. p. 21. Interpretive Summary: not required
Technical Abstract: In spite of rising feedstock costs and the grain-deficit status of the southeast, investors have committed to the construction of new ethanol plants in the region. The use of alternative feedstocks will help to alleviate market demand for corn both as a feedgrain and as an ethanol feedstock. As a drought tolerant grain requiring low nitrogen inputs, pearl millet may be a viable supplemental ethanol feedstock for the southeast. Limited information exists concerning genotype and environmental effects on grain yield, starch content and fermentation efficiency in pearl millet feedstocks. The objective of this study was to assess experimental pearl millet hybrids for genotype and environment effects on grain yield, starch, fermentation efficiency, and ethanol yield. Statewide yield trials were planted at Moultrie, Tifton, Watkinsville, and Newton GA in 2006, and at Moultrie, Tifton (early and late planted trials), Plains, and Newton GA and 2007. Nine genotypes were evaluated in 2006, and 6 genotypes were evaluated in 2007. Fertilizer was applied at 88 kg N/ha. Grain was combine-harvested, and yields were corrected to 15.5% moisture. Grain was evaluated for starch content on a dry basis. Fermentation efficiency was determined from the difference between observed and theoretical ethanol production. Experimental hybrid (606 x 2304) was among the top yielding hybrids at all locations. Across all locations, hybrid (606 x 2304) had 17% greater yield than the commercial standard Tifgrain 102 in 2006, and 30.3% greater yield in 2007. (606 x 2304) had 1.4 % and 2.2% greater starch compared to Tifgrain 102 in 2006 and 2007, respectively. Across all genotypes, mean grain yields were greatest in Watkinsville in 2006, and in the early Tifton trial in 2007. In both years, grain yields and starch content of the grain were lowest in the trials grown at Newton. Across all entries and locations, calculated ethanol yield per acre was highly correlated with grain yield per acre both in 2006 and 2007 (R2 > 0.99). It will be possible to select hybrids that produce higher levels of ethanol for the developing bioenergy industry in the southeast. Improving grain yield will be the most effective means of improving overall ethanol yield per unit of land.