Primed acclimation of cultivated peanut (Arachis hypogaea L.) through the use of deficit irrigation timed to crop developmental periods

Authors: ROWLAND, DIANE - University Of Florida; FAIRCLOTH, WILSON - Dow Agro Sciences; Payton, Paxton; TISSUE, DAVID - Western Sydney University; FERRELL, JASON - University Of Florida; Sorensen, Ronald - Ron; Butts, Christopher - Chris

Submitted to: Agricultural Water Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/27/2012
Publication Date: 7/12/2012
Publication URL: http://10.1016/j.agwat.2012.06.023
Citation: Rowland, D.L., Faircloth, W., Payton, P.R., Tissue, D.T., Ferrell, J.L., Sorensen, R.B., Butts, C.L. 2012. Primed acclimation of cultivated peanut (Arachis hypogaea L.) through the use of deficit irrigation timed to crop developmental periods. Agricultural Water Management. 113:85–95. doi.org/10.1016/j.agwat.2012.06.023.

Interpretive Summary: Achieving sustainability in global agriculture will ultimately depend on the water resources available to grow crops – whether through adequate and timely rainfall or through efficient irrigation application. Water scarcity and its escalating effects from climate change at present is the main environmental factor limiting crop production worldwide and is likely to remain the most critical barrier to food production in the future. In U.S. agriculture, the issue is further complicated by competition for water resources between urban and agricultural users. To provide sustainable solutions, tools are needed to optimize water application in irrigated systems. Solutions provided to date rely primarily on deficit irrigation (DI) schemes which typically apply less irrigation throughout the season than is lost through evapotranspiration. Field trials were conducted in 2005 and 2006 in Gaines County, Texas on a grower’s peanut field under a quarter section pivot covering approximately 65 ha (Jimbo Grissom Farms). Fifteen irrigation schemes were tested using water application rates of 100, 75, and 50% of typical irrigation amounts for this region (in this case, typical rates were 25–37 mm per week, depending on the pumping capacity during the season, which resulted in 380–560 mm per growing season). Soil moisture was monitored in both years using Watermark Granular Matrix Sensors (Irrometer® Company, Inc.) which measure soil water tension in kPa. Readings were taken by hand approximately 3 times a week during the entire growing season in three of the irrigation treatments: 100–100–100, 75–75–75, and 50–50–50. Due to the constraints of measuring soil moisture in all of the 15 irrigation treatments, these three treatments were chosen to provide quantification of the effect of fullseason DI schemes on soil moisture in comparison to the control (100–100–100). Yield, grade, and economic values were analyzed using Generalized Linear Models (SAS Institute Inc., Cary, NC). Year and irrigation were tested as main effects and for their interaction. Where appropriate, Fisher’s LSD test of means was used to describe difference in treatments. For the in-season crop measurements of NDVI and root measurements, analysis of variance (ANOVA) was performed with appropriate factors for each measurement type and Tukey’s multiple comparisons test were used to separate means when factors were significantly different (SAS JMP, SAS Institute Inc., Cary, NC). Precipitation patterns and ambient temperatures showed greater stress levels in 2006 which likely reduced yields across all treatments in comparison to 2005. Yields were reduced 26 (2005) and 10% (2006) in the lowest irrigation treatment (50% full season) compared with full irrigation (100% full season); but early-season water deficit (50 and 75% in the first 45 days after planting) followed by 100% irrigation in the mid- and late-seasons were successful at sustaining yield and/or crop value. Root growth was significantly enhanced at 50% irrigation compared with 100% irrigation, through greater root length, diameter, surface area, and depth, suggesting greater access to water during mid- and late-season periods. These results suggest that early to mid-season deficit irrigation has the potential to maintain peanut yield without altering quality, and to substantially reduce water use in this semi-arid environment.

Technical Abstract: Water-deficits and high temperatures are the predominant factors limiting peanut production across the U.S., either because of regional aridity or untimely rainfall events during crucial crop developmental periods. In the southern High Plains of west Texas and eastern New Mexico, low average annual rainfall (450 mm) and high evaporative demand necessitates the use of significant irrigation in production systems. In this west Texas study, the primary objective was to develop irrigation schemes that maximized peanut yield and grade while reducing overall water consumption. Therefore, a large-scale field experiment was established in 2005 and 2006 that utilized 15 treatment combinations of differing rates of irrigation (50, 75, and 100% of grower applied irrigation) applied at different periods of peanut development (early, middle, and late season). Precipitation patterns and ambient temperatures showed greater stress levels in 2006 which likely reduced yields across all treatments in comparison to 2005. Yields were reduced 26 (2005) and 10% (2006) in the lowest irrigation treatment (50% full season) compared with full irrigation (100% full season); but early-season water deficit (50 and 75% in the first 45 days after planting) followed by 100% irrigation in the mid- and late-seasons were successful at sustaining yield and/or crop value. Root growth was significantly enhanced at 50% irrigation compared with 100% irrigation, through greater root length, diameter, surface area, and depth, suggesting greater access to water during mid- and late-season periods. These results suggest that early to mid-season deficit irrigation has the potential to maintain peanut yield without altering quality, and to substantially reduce water use in this semi-arid environment. (c) 2012 Elsevier B.V. All rights reserved.