Upendra Sainju - Academia.edu (original) (raw)

Dr. Upendra M. Sainju has been working as a Senior Research Soil Scientist in dryland and irrigated cropping systems for the past 14 years in USDA, Agricultural Research Service, Sidney, Montana. Prior to this, he worked as postdoctoral associate and visiting scientist in Rutgers University, Washington State University, Fort Valley State University, and Tribhuvan University, Nepal from 1973-2004. He received Ph.D. from University of Kentucky, M.S. from University of Florida, and B.S. from University of Udaipur, India. He is nationally and internationally renowned in developing soil and crop management practices that increase crop yields and quality, sequester carbon (C) and nitrogen (N) in the soil, increase organic matter, improve soil quality and productivity, reduce N fertilization rate and N leaching, and mitigate greenhouse gas emissions. Over the past 44 years, he has conducted extensive research on the effects of tillage, cropping systems, crop rotation, cover crops, N fertilization rates, poultry litter application, sheep grazing, and irrigation on soil C and N cycling, greenhouse gas emissions, and crop yields. His research accomplishments have been documented in 130 peer-reviewed journals, 15 book chapters, 20 proceedings, 40 popular press, 4 technical reports, and 150 abstracts. He has actively participated in American Society of Agronomy (ASA) and Soil Science Society of America (SSSA) by serving in ASA community leader (Soil Carbon and Greenhouse Gas Emissions), committees (ASA and SSSA Fellows Committees, Best Paper Review Committee, Applied Soil Science Award Committee, Environmental Quality Award Committee), meetings (session chair, moderator, and paper presentation), reviewer of more than 30 journals, and Associate and Academic Editors in Agronomy Journal (2009-2012), Journal of Environmental Quality (2015-present), and PLOS ONE (2014-present). He received Soil Science Society of America Fellow in 2014 and American Society of Agronomy Fellow in 2015. He also received outstanding certificate of merit award in USDA (2011-present), outstanding research award (Fort Valley State University, Georgia, 2004), and phenomenal and worthy keynote presentation in 5th International Conference in Agriculture and Horticulture, June 27-19, 2016, Cape Town, South Africa. He has received more $5 million research grants from USDA and other organizations in collaboration with national and international universities to conduct research in soil, environmental, and crop sciences.

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Papers by Upendra Sainju

Efforts have increased to measure nitrate losses from farmland under different management practic... more Efforts have increased to measure nitrate losses from farmland under different management practices due to environmental and public concerns over levels of nitrate-nitrogen (NO 3-N) in surface and ground waters. This study evaluated the effect of conventional tillage (CT) and strip tillage (ST) practices and three N application rates on NO 3-N concentrations in soil water at a 76 cm depth under irrigated sugar-beet (Beta vulgaris L.) in a clay loam soil. Nitrogen rates were applied as dry urea at 120, 150, 180 kg N ha −1 in 2006; 130, 160, 190 kg N ha −1 in 2007; and 110, 140, 170 kg N ha −1 in 2008. Soil water volumes were measured weekly during each growing season using three ceramic suction cup samplers per plot placed at a 76 cm depth below the soil surface under each tillage. Results indicated that NO 3-N concentrations at the 76 cm depth in the soil profile were not significantly affected by either tillage practice or by N application rate due to soil variability across the field and due to suction cup samplers' biased estimate of soil water. The three N rates under CT and ST practices maintained NO 3-N concentrations below the root zone to levels exceeding the 10 mg L −1 safe drinking water maximum level in all three years. There were large variations in NO 3-N concentrations among replicates within each tillage and N rate that were likely caused by variability in soil physical, hydraulic and chemical properties that impacted water movement through the soil profile, N dynamics and leaching below the root zone of sugarbeet. In conclusion, suction cup samplers are point water measurement devices that reveal considerable variability among replicates within each treatment due to the heterogeneity of field soils. Further, these samplers are not recommended in heterogeneous soils with preferential flow characteristics.

Nitrogen balance provides a measure of agroecosystem performance and environmental sustainability... more Nitrogen balance provides a measure of agroecosystem performance and environmental sustainability by taking into accounts of N inputs and outputs and N retention in the soil. The objective of this study was to evaluate N balance based on N inputs and outputs and soil N sequestration after 7 yr in response to five dryland crop rotations (two 4-yr stacked and two 4-yr alternate-year rotations and one monocropping) and two cultural practices arranged in a split-plot design in the northern Great Plains, USA. Stacked rotations were durum (Triticum turgidum L.)-durum-canola (Brassica napus L.)-pea (Pisum sativum L.) (D-D-C-P) and durum-durum-flax (Linum usitatissimum L.)-pea (D-D-F-P). Alternate-year rotations were durum-canola-durum-pea (D-C-D-P) and durum-flax-durum-pea (D-F-D-P). Monocroppping was continuous durum (CD). Cultural practices were traditional (conventional till, recommended seed rate, broadcast N fertilization, and reduced stubble height) and ecological (no-till, increased seed rate, banded N fertilization, and increased stubble height). Total annual N input due to N fertilization, pea N fixation, atmospheric N deposition, crop seed N, and nonsymbiotic N fixation was lower in CD than other crop rotations, regardless of cultural practices. Total N output due to crop grain N removal and N losses due to denitrification, volatilization, plant senescence, N leaching, gaseous N (NO x) emissions, and surface runoff was lower in traditional CD and D-. Nitrogen sequestration rate at 0–125 cm from 2005 to 2011 ranged from 40 kg N ha À1 yr À1 for ecological D-D-F-P to 52 kg N ha À1 yr À1 for ecological CD. Nitrogen balance ranged from À39 to À36 kg N ha À1 yr À1 with CD compared to 9–25 kg N ha À1 yr À1 with other crop rotations in both cultural practices. Because of reduced reliance on external N inputs and increased grain N removal, N flow, and N surplus, crop rotations with legumes, nonlegumes, and oilseed crops in the rotation can be productive and environmentally sustainable compared with monocropping, regardless of cultural practices. Published by Elsevier B.V.

ABSTRACT Diversification of continuous durum system can improve economic and environmental sustai... more ABSTRACT Diversification of continuous durum system can improve economic and environmental sustainability in semiarid cropping systems, but little is known about the influence of rotation type and management system on durum performance. We conducted a study from 2005 to 2011 comparing two sets of crops in stacked (durum-durum-canola-pea and durum-durum-flax-pea) and alternate-year (durum-canola-durum-pea and durum-flax-durum-pea) rotations under conventional and ecological management levels on durum yield and characteristics. Continuous durum was included as a control. Conventional management included preplant tillage, broadcast urea, standard seeding rates, and short durum residue height. Ecological management included zero tillage, banded urea at planting, greater seeding rates, and tall durum residue height. Average durum grain yield, plant height, and plant stand across years were lower in durum-durum-canola-pea than other rotations under the conventional but not under the ecological management. Overall, rotation type rarely influenced yield or yield components of durum. Durum yield was greater in three out of six years under the ecological than under the conventional management. Durum was taller, with more reproductive tillers but fewer seed per head, under the ecological than under the conventional management. Stacked rotation of durum with pea in the conventional management resulted in reduced durum grain yield and performance compared to other treatments in dryland cropping systems in the northern Great Plains.

Communications in Soil Science and Plant Analysis, Sep 9, 2011

European Journal of Soil Biology, Mar 1, 2010

Agronomy Journal, Jul 1, 2001

Page 1. 878 AGRONOMY JOURNAL, VOL. 93, JULY–AUGUST 2001 ten Berge, HFM, QH Shi, Z. Zheng, KS Rao,... more Page 1. 878 AGRONOMY JOURNAL, VOL. 93, JULY–AUGUST 2001 ten Berge, HFM, QH Shi, Z. Zheng, KS Rao, JJM Riethoven, Yang, X., V. Roemheld, H. Marschner, VC Baligar, and DV Mar-and XH Zhong. 1997. Numerical optimization of nitrogen applica-tens. 1997. ...

ABSTRACT Crucifer oilseeds as renewable biofuels feedstock could offset demand for petroleum-base... more ABSTRACT Crucifer oilseeds as renewable biofuels feedstock could offset demand for petroleum-based alternatives. Current knowledge is limited regarding crop yield potential and N management in semi-arid cropping systems. In NE Montana, a 5-yr study considered no-till production of durum (Triticum durum Desf.) in rotation with oilseed crucifers camelina [Camelina sativa (L.) Crantz], crambe (Crambe abyssinica Hochst. ex R.E. Fries), and Brassica juncea L. canola, with durum-chemical fallow as the control. The N use efficiency was significantly related to seed yield in the three crucifer oilseeds and that juncea canola typically utilized N more efficiently than crambe and camelina. Similarly, N use efficiency was significantly related to grain yield in durum following oilseeds. Yield of durum following juncea canola was as great as that for durum following fallow and greater than that for durum following camelina or crambe. Durum following camelina, juncea canola, or fallow used N more efficiently than durum following crambe. Yield and N use of oilseeds and durum varied significantly among years, however, underlying the need to further develop durum-oilseed cropping systems in semi-arid environments.

Soil and Tillage Research, May 31, 2009

ABSTRACT Lack of diversification constrains dryland spring wheat (Triticum aestivum L.) productio... more ABSTRACT Lack of diversification constrains dryland spring wheat (Triticum aestivum L.) production in the northern Great Plains. We initiated a field study in 2004 comparing four crop rotations with each component present in a two-by-two matrix of tillage (conventional vs. zero tillage) and management (conventional vs. ecological) systems. Rotations were continuous spring wheat (SW), SW-pea, SW-barley hay-pea, and SW-barley hay-corn-pea. Ecological management practices varied by crop and were designed to improve snow capture and competitiveness with weeds. Tillage system rarely influenced SW production. Conversely, rotation and management system interacted with years. Over six years, SW in diversified rotations typically had greater soil water content at planting, resulting in greater water use and 473 kg ha-1 additional grain yield than continuous SW. Conversely, ecologically managed SW averaged 644 kg ha-1 less yield than conventionally managed SW. Diversified rotations improved SW yield under semi-arid conditions.

Soil Science Society of America Journal, 2009

2 emissions and to increase C sequestration. We evaluated the eff ects of tillage and cropping se... more 2 emissions and to increase C sequestration. We evaluated the eff ects of tillage and cropping sequence combinations and N fertilization on dryland crop biomass (stems + leaves) and soil surface CO 2 fl ux and C content (0- to 120-cm depth) in a Williams loam from May to October, 2006 to 2008, in eastern Montana. Treatments were no-tilled continuous

Soil Science Society of America Journal, 2003

Nutrient Cycling in Agroecosystems, 2014

SpringerPlus, 2015

Information on the effect of long-term management on soil nutrients and chemical properties is sc... more Information on the effect of long-term management on soil nutrients and chemical properties is scanty. We examined the 30-year effect of tillage frequency and cropping sequence combination on dryland soil Olsen-P, K, Ca, Mg, Na, SO4-S, and Zn concentrations, pH, electrical conductivity (EC), and cation exchange capacity (CEC) at the 0-120 cm depth and annualized crop yield in the northern Great Plains, USA. Treatments were no-till continuous spring wheat (Triticum aestivum L.) (NTCW), spring till continuous spring wheat (STCW), fall and spring till continuous spring wheat (FSTCW), fall and spring till spring wheat-barley (Hordeum vulgare L., 1984-1999) followed by spring wheat-pea (Pisum sativum L., 2000-2013) (FSTW-B/P), and spring till spring wheat-fallow (STW-F, traditional system). At 0-7.5 cm, P, K, Zn, Na, and CEC were 23-60% were greater, but pH, buffer pH, and Ca were 6-31% lower in NTCW, STCW, and FSTW-B/P than STW-F. At 7.5-15 cm, K was 23-52% greater, but pH, buffer pH, and Mg were 3-21% lower in NTCW, STCW, FSTCW, FSTW-B/P than STW-F. At 60-120 cm, soil chemical properties varied with treatments. Annualized crop yield was 23-30% lower in STW-F than the other treatments. Continuous N fertilization probably reduced soil pH, Ca, and Mg, but greater crop residue returned to the soil increased P, K, Na, Zn, and CEC in NTCW and STCW compared to STW-F. Reduced tillage with continuous cropping may be adopted for maintaining long-term soil fertility and crop yields compared with the traditional system.

Efforts have increased to measure nitrate losses from farmland under different management practic... more Efforts have increased to measure nitrate losses from farmland under different management practices due to environmental and public concerns over levels of nitrate-nitrogen (NO 3-N) in surface and ground waters. This study evaluated the effect of conventional tillage (CT) and strip tillage (ST) practices and three N application rates on NO 3-N concentrations in soil water at a 76 cm depth under irrigated sugar-beet (Beta vulgaris L.) in a clay loam soil. Nitrogen rates were applied as dry urea at 120, 150, 180 kg N ha −1 in 2006; 130, 160, 190 kg N ha −1 in 2007; and 110, 140, 170 kg N ha −1 in 2008. Soil water volumes were measured weekly during each growing season using three ceramic suction cup samplers per plot placed at a 76 cm depth below the soil surface under each tillage. Results indicated that NO 3-N concentrations at the 76 cm depth in the soil profile were not significantly affected by either tillage practice or by N application rate due to soil variability across the field and due to suction cup samplers' biased estimate of soil water. The three N rates under CT and ST practices maintained NO 3-N concentrations below the root zone to levels exceeding the 10 mg L −1 safe drinking water maximum level in all three years. There were large variations in NO 3-N concentrations among replicates within each tillage and N rate that were likely caused by variability in soil physical, hydraulic and chemical properties that impacted water movement through the soil profile, N dynamics and leaching below the root zone of sugarbeet. In conclusion, suction cup samplers are point water measurement devices that reveal considerable variability among replicates within each treatment due to the heterogeneity of field soils. Further, these samplers are not recommended in heterogeneous soils with preferential flow characteristics.

Nitrogen balance provides a measure of agroecosystem performance and environmental sustainability... more Nitrogen balance provides a measure of agroecosystem performance and environmental sustainability by taking into accounts of N inputs and outputs and N retention in the soil. The objective of this study was to evaluate N balance based on N inputs and outputs and soil N sequestration after 7 yr in response to five dryland crop rotations (two 4-yr stacked and two 4-yr alternate-year rotations and one monocropping) and two cultural practices arranged in a split-plot design in the northern Great Plains, USA. Stacked rotations were durum (Triticum turgidum L.)-durum-canola (Brassica napus L.)-pea (Pisum sativum L.) (D-D-C-P) and durum-durum-flax (Linum usitatissimum L.)-pea (D-D-F-P). Alternate-year rotations were durum-canola-durum-pea (D-C-D-P) and durum-flax-durum-pea (D-F-D-P). Monocroppping was continuous durum (CD). Cultural practices were traditional (conventional till, recommended seed rate, broadcast N fertilization, and reduced stubble height) and ecological (no-till, increased seed rate, banded N fertilization, and increased stubble height). Total annual N input due to N fertilization, pea N fixation, atmospheric N deposition, crop seed N, and nonsymbiotic N fixation was lower in CD than other crop rotations, regardless of cultural practices. Total N output due to crop grain N removal and N losses due to denitrification, volatilization, plant senescence, N leaching, gaseous N (NO x) emissions, and surface runoff was lower in traditional CD and D-. Nitrogen sequestration rate at 0–125 cm from 2005 to 2011 ranged from 40 kg N ha À1 yr À1 for ecological D-D-F-P to 52 kg N ha À1 yr À1 for ecological CD. Nitrogen balance ranged from À39 to À36 kg N ha À1 yr À1 with CD compared to 9–25 kg N ha À1 yr À1 with other crop rotations in both cultural practices. Because of reduced reliance on external N inputs and increased grain N removal, N flow, and N surplus, crop rotations with legumes, nonlegumes, and oilseed crops in the rotation can be productive and environmentally sustainable compared with monocropping, regardless of cultural practices. Published by Elsevier B.V.

ABSTRACT Diversification of continuous durum system can improve economic and environmental sustai... more ABSTRACT Diversification of continuous durum system can improve economic and environmental sustainability in semiarid cropping systems, but little is known about the influence of rotation type and management system on durum performance. We conducted a study from 2005 to 2011 comparing two sets of crops in stacked (durum-durum-canola-pea and durum-durum-flax-pea) and alternate-year (durum-canola-durum-pea and durum-flax-durum-pea) rotations under conventional and ecological management levels on durum yield and characteristics. Continuous durum was included as a control. Conventional management included preplant tillage, broadcast urea, standard seeding rates, and short durum residue height. Ecological management included zero tillage, banded urea at planting, greater seeding rates, and tall durum residue height. Average durum grain yield, plant height, and plant stand across years were lower in durum-durum-canola-pea than other rotations under the conventional but not under the ecological management. Overall, rotation type rarely influenced yield or yield components of durum. Durum yield was greater in three out of six years under the ecological than under the conventional management. Durum was taller, with more reproductive tillers but fewer seed per head, under the ecological than under the conventional management. Stacked rotation of durum with pea in the conventional management resulted in reduced durum grain yield and performance compared to other treatments in dryland cropping systems in the northern Great Plains.

Communications in Soil Science and Plant Analysis, Sep 9, 2011

European Journal of Soil Biology, Mar 1, 2010

Agronomy Journal, Jul 1, 2001

Page 1. 878 AGRONOMY JOURNAL, VOL. 93, JULY–AUGUST 2001 ten Berge, HFM, QH Shi, Z. Zheng, KS Rao,... more Page 1. 878 AGRONOMY JOURNAL, VOL. 93, JULY–AUGUST 2001 ten Berge, HFM, QH Shi, Z. Zheng, KS Rao, JJM Riethoven, Yang, X., V. Roemheld, H. Marschner, VC Baligar, and DV Mar-and XH Zhong. 1997. Numerical optimization of nitrogen applica-tens. 1997. ...

ABSTRACT Crucifer oilseeds as renewable biofuels feedstock could offset demand for petroleum-base... more ABSTRACT Crucifer oilseeds as renewable biofuels feedstock could offset demand for petroleum-based alternatives. Current knowledge is limited regarding crop yield potential and N management in semi-arid cropping systems. In NE Montana, a 5-yr study considered no-till production of durum (Triticum durum Desf.) in rotation with oilseed crucifers camelina [Camelina sativa (L.) Crantz], crambe (Crambe abyssinica Hochst. ex R.E. Fries), and Brassica juncea L. canola, with durum-chemical fallow as the control. The N use efficiency was significantly related to seed yield in the three crucifer oilseeds and that juncea canola typically utilized N more efficiently than crambe and camelina. Similarly, N use efficiency was significantly related to grain yield in durum following oilseeds. Yield of durum following juncea canola was as great as that for durum following fallow and greater than that for durum following camelina or crambe. Durum following camelina, juncea canola, or fallow used N more efficiently than durum following crambe. Yield and N use of oilseeds and durum varied significantly among years, however, underlying the need to further develop durum-oilseed cropping systems in semi-arid environments.

Soil and Tillage Research, May 31, 2009

ABSTRACT Lack of diversification constrains dryland spring wheat (Triticum aestivum L.) productio... more ABSTRACT Lack of diversification constrains dryland spring wheat (Triticum aestivum L.) production in the northern Great Plains. We initiated a field study in 2004 comparing four crop rotations with each component present in a two-by-two matrix of tillage (conventional vs. zero tillage) and management (conventional vs. ecological) systems. Rotations were continuous spring wheat (SW), SW-pea, SW-barley hay-pea, and SW-barley hay-corn-pea. Ecological management practices varied by crop and were designed to improve snow capture and competitiveness with weeds. Tillage system rarely influenced SW production. Conversely, rotation and management system interacted with years. Over six years, SW in diversified rotations typically had greater soil water content at planting, resulting in greater water use and 473 kg ha-1 additional grain yield than continuous SW. Conversely, ecologically managed SW averaged 644 kg ha-1 less yield than conventionally managed SW. Diversified rotations improved SW yield under semi-arid conditions.

Soil Science Society of America Journal, 2009

2 emissions and to increase C sequestration. We evaluated the eff ects of tillage and cropping se... more 2 emissions and to increase C sequestration. We evaluated the eff ects of tillage and cropping sequence combinations and N fertilization on dryland crop biomass (stems + leaves) and soil surface CO 2 fl ux and C content (0- to 120-cm depth) in a Williams loam from May to October, 2006 to 2008, in eastern Montana. Treatments were no-tilled continuous

Soil Science Society of America Journal, 2003

Nutrient Cycling in Agroecosystems, 2014

SpringerPlus, 2015

Information on the effect of long-term management on soil nutrients and chemical properties is sc... more Information on the effect of long-term management on soil nutrients and chemical properties is scanty. We examined the 30-year effect of tillage frequency and cropping sequence combination on dryland soil Olsen-P, K, Ca, Mg, Na, SO4-S, and Zn concentrations, pH, electrical conductivity (EC), and cation exchange capacity (CEC) at the 0-120 cm depth and annualized crop yield in the northern Great Plains, USA. Treatments were no-till continuous spring wheat (Triticum aestivum L.) (NTCW), spring till continuous spring wheat (STCW), fall and spring till continuous spring wheat (FSTCW), fall and spring till spring wheat-barley (Hordeum vulgare L., 1984-1999) followed by spring wheat-pea (Pisum sativum L., 2000-2013) (FSTW-B/P), and spring till spring wheat-fallow (STW-F, traditional system). At 0-7.5 cm, P, K, Zn, Na, and CEC were 23-60% were greater, but pH, buffer pH, and Ca were 6-31% lower in NTCW, STCW, and FSTW-B/P than STW-F. At 7.5-15 cm, K was 23-52% greater, but pH, buffer pH, and Mg were 3-21% lower in NTCW, STCW, FSTCW, FSTW-B/P than STW-F. At 60-120 cm, soil chemical properties varied with treatments. Annualized crop yield was 23-30% lower in STW-F than the other treatments. Continuous N fertilization probably reduced soil pH, Ca, and Mg, but greater crop residue returned to the soil increased P, K, Na, Zn, and CEC in NTCW and STCW compared to STW-F. Reduced tillage with continuous cropping may be adopted for maintaining long-term soil fertility and crop yields compared with the traditional system.

Annual hay crops help diversify wheat-based dryland cropping systems and provide a source of live... more Annual hay crops help diversify wheat-based dryland cropping systems and provide a source of livestock feed in the northern Great Plains (NGP). However, little is known about the impact crop diversification, tillage, or management system on N use relationships of annual forages such as barley (Hordeum vulare L.) hay. A study from 2009-2012 that was initiated in 2004 was conducted in northeast Montana to investigate barley hay production in a factorial of two rotations (barley hay-pea [Pisum sativum L]-wheat [Triticum aestivum L.] vs. barley hay-corn [Zea mays L.]-pea-wheat), two tillage systems (till vs. no-till), and two management systems (conventional and ecological). Ecological management included greater seeding rate, banded (vs. broadcast) fertilizer N, and taller wheat stubble height than conventional management. Available N and N use were greater in the 3-yr rotation, but barley hay yields were similar to those in a 4-yr rotation, which also had a greater N recovery index suggesting more efficient N use in the further diversified 4-yr rotation. Ecologically managed barley hay had greater biomass yield than conventionally managed barley hay, though management system had little impact on measured soil N or plant N relationships. Tillage system rarely impacted barley hay N relationships. All measured barley hay production and N relationships varied significantly by year, stressing the need to further develop cropping systems that optimize N utilization despite the highly variable precipitation typical of the NGP.