Influence of water use and environmental parameters on proso millet yield

Authors: NIELSEN, DAVID; VIGIL, MERLE

Submitted to: Field Crops Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/22/2017
Publication Date: 7/10/2017
Publication URL: http://handle.nal.usda.gov/10113/5703266
Citation: Nielsen, D.C., Vigil, M.F. 2017. Influence of water use and environmental parameters on proso millet yield. Field Crops Research. 212:34-44. doi:10.1016/j.fcr.2017.06.025.

Interpretive Summary: Grain sorghum is a highly adapted, water use efficient crop for diversifying Central Great Plains cropping systems. A water-limited yield relationship was defined from 22 years of water use and yield data collected at Akron, CO that demonstrated a water use/yield response of 32.57 kg/ha per mm of water use (13.2 bu/a per inch of water use). However, there were many years in which the millet yields obtained were far below what would be expected based on the amount of water use. Important factors that were found to influence the yield in addition to growing season water use were plant available water in the 0-120 cm soil profile (0-4 ft) and precipitation received from 12-18 August (which increased yield), and number of days in July and August with maximum temperature greater than 35 degrees C, daily average wind run and maximum wind gust during the week before swathing (which decreased yield). These results suggest that that closing the yield gap for proso millet production could likely result from efforts to breed for enhanced shattering resistance and heat tolerance and from production methods that improve precipitation storage efficiency during the non-crop period prior to millet planting and increase available soil water at millet planting.

Technical Abstract: Proso millet (Panicum miliaceum L.) is a short-season, drought-tolerant C4 species capable of making use of limited available water supplies and is suitable for dryland crop rotations in the central Great Plains. Previously published water use/yield production functions for proso millet have slopes lower than reported for other C4 species in this region. The objectives of this experiment were to determine the water-limited yield relationship for proso millet and to identify environmental factors that cause yields to be lower than predicted by the water-limited yield relationship. Water use and yield data were obtained from a long-term crop rotation experiment conducted under dryland conditions in northeast Colorado from 1995 to 2016. Stepwise linear regression analysis was used to determine important environmental factors influencing yield. The water-limited yield relationship had a slope consistent with other C4 species in this region (32.57 kg ha-1 per mm of water use). A relationship based on growing season water use, plant available soil water at planting, precipitation received from 12-18 August, number days in July and August with maximum temperature greater than 36 degrees C, daily average wind run and maximum wind gust during the week before swathing explained 88% of yield variability. The results of this analysis suggest that closing the yield gap for proso millet production could likely result from efforts to breed for enhanced shattering resistance and heat tolerance and from production methods that improve precipitation storage efficiency during the non-crop period prior to millet planting and increase available soil water at millet planting.