Dryland Corn and Grain Sorghum Yield Response to Available Soil Water at Planting

Abstract

A gronomy J our n al • Volume 110 , I ssue 1 • 2 018 W ater availability at critical growth stages of crops is the major yield limiting factor in dryland crop production (Farahani et al., 1998;Allen, 2012). Dryland agriculture is a special case of rainfed agriculture practiced in arid and semiarid regions. In these regions when irrigation is not used, water conservation becomes the primary focus of management decisions because growing season precipitation is seldom suffi cient to fully meet evapotranspiration demand. Conditions of moderate to severe plant water stress occur during a substantial part of the year and storage of water during fallow for use by a subsequent crop is oft en practiced (Nielsen et al., 2016). Available soil water at planting and ISP are usually the only two sources of water for annual crops such as corn and grain sorghum grown in dryland systems. However, the singular contribution of ASWP for corn and grain sorghum yield was seldom studied.Th e impact of water availability on grain yields of corn and grain sorghum has been studied in depth through yield relationships with ISP or diff erent irrigation levels Payero et al., 2006;Klocke et al., 2011;Assefa et al., 2014;) and with crop water use (Nielsen and Vigil, 2017). Th e infl uence of cropping system on ASWP and on subsequent grain yield has been reported for wheat (Triticum aestivum L.) (Nielsen et al., 2002;Nielsen and Vigil, 2005) and results from these studies indicated that wheat yields were correlated with ASWP. Th e results from Nielsen and Vigil (2005) also suggest that the relationship between ASWP and wheat yield varied year-to-year depending on evaporative demand and ISP. Studies in water-yield relationships of proso millet (Panicum miliaceum L.), pea (Pisum sativum L.), triticale (Tritico secale rimpaui Wittm.), foxtail millet (Setaria italic L. Beauv.), corn, grain sorghum, bean (Phaseolus vulgaris L.), and sunfl ower (Helianthus annuus L.) (Lyon et al., 1995;Felter et al., 2006;Nielsen et al., 2009) suggest that the eff ect of ASWP was greater for short duration crops (bean, proso millet) compared with long duration crops (corn, grain sorghum, sunfl ower).Increase in ASWP due to changes in management practices was among the main factors that contributed to the greater portion of the 139% grain sorghum yield increase in the years 1939 to 1997 (Unger and Baumhardt, 1999 Core Ideas• Yield gains from available soil water at planting decreased as inseason precipitation increased.• Corn yield gain 27 to 33 kg ha -1 (mm available soil water at planting) -1 at in-season precipitation of 196 to 215 mm.• Corn yield gain 9 to 25 kg ha -1 (mm available soil water at planting) -1 as in-season precipitation increased to 288 to 354 mm.• Sorghum yield gain 12 to 22 kg ha -1 (mm available soil water at planting) -1 at in-season precipitation of 163 to 281 mm.• Sorghum yield gain 0 to 6 kg ha -1 (mm available soil water at planting) -1 at in-season precipitation of 315 to 382 mm.

Dryland Corn Production and Water Use Affected by Tillage and Crop Management Intensity

“…Reduced heat stress and enhanced soil water availability due to above-average precipitation may have increased grain yield in these years. Dryland corn grain yield responds linearly to available soil water from precipitation and irrigation (Nielsen et al, 2010;Schlegel et al, 2018). Increased grain yield compared with biomass increased harvest index in 2006, 2009, and 2010 when air temperature and precipitation were favorable for corn growth compared with other years.…”

Integrating cover crops for weed management in the semiarid U.S. Great Plains: opportunities and challenges

“…The fallow phase of the production system is critical for conservation of soil water that stabilizes wheat yields and prevents crop failure in drier years in NT regions of the semiarid Great Plains (Haas et al 1974;Nielsen and Vigil 2010). In this water-limited environment, crop yields are directly related to available soil moisture at time of cash crop seeding (Schlegel et al 2018). Despite the weed-suppression benefits of CCs, previous research demonstrated that replacing fallow with CCs often resulted in decreased soil water content at time of cash crop seeding (Holman et al 2018;Nielsen and Vigil 2018;Schlegel and Havlin 1997;Unger and Vigil 1998;Zentner et al 1996).…”

“…), and chick pea (Cicer arietinum L.) have replaced a portion of this fallow period in the northern parts (Miller et al 2003). Similarly, several new crops have been evaluated in 3-or 4-yr rotation schemes by including cereal crops (Nielsen and Vigil 2018;Schlegel et al 2018), legumes as forage and grain crops (Holman et al 2018;Lyon et al 2004), and recently oilseed crops (Obour et al 2018) for potential replacement of fallow in the Central Great Plains (Figure 1). Despite these efforts to increase cropping intensity, crop rotations in the region still include a fallow phase, and most growers practice fallow as a strategy to minimize risk of drought and crop failure.…”

Preplant Irrigation Effectiveness and Crop Yield and Water Productivity in the United States: A Review

“…Bushong et al reported the impact of preplant irrigation on phosphorus and potassium fertilizer management in winter wheat with grain yield and water productivity optimized under preplant irrigation condition [35]. Schlegel et al found an increase in rainfed maize grain yield from 27 to 33 kg/ha/mm of pre-plant irrigation when in-season precipitation ranged from 196 to 215 mm and yield decrease from 9 to 25 kg/ha/mm when the in-season precipitation ranged from 288 to 354 mm under increasing preplant irrigation amounts (0, 38, 76, or 114 mm) at two locations in Kansas [36]. Rainfed grain sorghum yield also increased with increasing preplant irrigation amounts from 12 to 22 kg/ha/mm and from 0 to 6 kg/ha/ mm under in-season precipitation ranges of 163 -281 mm and 315 -382 mm respectively [36].…”

“…Schlegel et al found an increase in rainfed maize grain yield from 27 to 33 kg/ha/mm of pre-plant irrigation when in-season precipitation ranged from 196 to 215 mm and yield decrease from 9 to 25 kg/ha/mm when the in-season precipitation ranged from 288 to 354 mm under increasing preplant irrigation amounts (0, 38, 76, or 114 mm) at two locations in Kansas [36]. Rainfed grain sorghum yield also increased with increasing preplant irrigation amounts from 12 to 22 kg/ha/mm and from 0 to 6 kg/ha/ mm under in-season precipitation ranges of 163 -281 mm and 315 -382 mm respectively [36]. Stone, et al investigated the timing of off-season irrigation in maize in Kansas and found that offseason irrigation timing did not significantly impact maize yield and concluded that off-season irrigation of maize was not a water efficient practice [20].…”