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Dr. Koffi Djaman
New Mexico State University

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Review
Published: 02 June 2021 in Sustainability
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Interest in organic foods is increasing at a moment when humanity is facing a range of health challenges including the concern that some conventionally produced foods may pose possible adverse effects on human and livestock health. With the increasing human population, intensive production is increasingly trending towards high-input systems that aim to close yield gaps, increase crop yields, and develop new crop varieties with higher yield potential and tolerance to biotic and abiotic stresses, all within the context of incorporating specific traits to satisfy consumer demand. Potato (Solanum tuberosum L.) is one of the most consumed foods under different cultural diets; however, its production faces some challenges related to soilborne diseases, marketable yield and quality, sugars and dry matter content of the produced tubers, tuber content in terms of nitrate, minerals, vitamins, bioactive compounds, and antioxidants, and consumer appreciation regarding the sensory characteristics of tubers and processed products. Different studies have been investigating some of these challenges, with sometimes straightforward and sometimes conflicting results. This variability in research results indicates the general non-transferability of the results from one location to another under the same management practices in addition to differences in plant material. This review compares some characteristics of raw or boiled potato and processed products from potato tubers grown organically and conventionally. Ideally, such information may be of benefit in decision making by consumers in their dietary choices, by potato growers in their selection of crop management practices, and by scientists looking at potential areas for future research on potatoes.

ACS Style

Koffi Djaman; Soum Sanogo; Komlan Koudahe; Samuel Allen; Aminou Saibou; Samuel Essah. Characteristics of Organically Grown Compared to Conventionally Grown Potato and the Processed Products: A Review. Sustainability 2021, 13, 6289 .

AMA Style

Koffi Djaman, Soum Sanogo, Komlan Koudahe, Samuel Allen, Aminou Saibou, Samuel Essah. Characteristics of Organically Grown Compared to Conventionally Grown Potato and the Processed Products: A Review. Sustainability. 2021; 13 (11):6289.

Chicago/Turabian Style

Koffi Djaman; Soum Sanogo; Komlan Koudahe; Samuel Allen; Aminou Saibou; Samuel Essah. 2021. "Characteristics of Organically Grown Compared to Conventionally Grown Potato and the Processed Products: A Review." Sustainability 13, no. 11: 6289.

Full length research article
Published: 17 March 2021 in Agricultural Research
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Alfalfa (Medicago sativa L.) is one of the most important forage crops to farmers and ranchers in the USA. Plants potential yield quality and its persistence are some of the key traits breeders have targeted to improve crop productivity and adaptation. The objective of this study was to evaluate different sets of alfalfa cultivars under fall and spring plantings for forage yield stability. Field experiments were conducted under sprinkler irrigation at New Mexico State University’s Agricultural Science Center at Farmington to evaluate forage yield of 18, 18, 22, 24, 24, 22, and 22 selected alfalfa cultivars planted in fall 2001, spring 2004, fall 2005, fall 2007, fall 2009, spring 2012, and fall 2014, respectively. The selected alfalfa cultivars were arranged in a randomized complete block design with four replications. The long-term 2001–2018 average annual forage yield of fall planted alfalfa was 21.70 Mg/ha, while the average annual forage yield of the spring planted alfalfa was 19.14 Mg/ha. Forage yield was consistent throughout years with negligible variations. Moderately dormant (FD 5) alfalfa cultivars slightly yielded higher than semidormant (FD 6, 7) cultivars, which showed the lowest forage yield from all the experiments (include the FD grouping means across tests with the LSD). Overall, annual forage yield decreased with fall dormancy rate (FD) at the rate of 0.34 Mg ha−1/FDR. Dormant and moderately dormant alfalfa cultivars should be of first choice in northwestern New Mexico and regions with similar pedoclimatic conditions.

ACS Style

Koffi Djaman; Michael O’Neill; Leonard Lauriault; Mark Marsalis; Komlan Koudahe; Murali K. Darapuneni. The Dynamics of Forage Yield of Different Fall Dormancy Rating Alfalfa Cultivars in a Semiarid Climate. Agricultural Research 2021, 10, 378 -389.

AMA Style

Koffi Djaman, Michael O’Neill, Leonard Lauriault, Mark Marsalis, Komlan Koudahe, Murali K. Darapuneni. The Dynamics of Forage Yield of Different Fall Dormancy Rating Alfalfa Cultivars in a Semiarid Climate. Agricultural Research. 2021; 10 (3):378-389.

Chicago/Turabian Style

Koffi Djaman; Michael O’Neill; Leonard Lauriault; Mark Marsalis; Komlan Koudahe; Murali K. Darapuneni. 2021. "The Dynamics of Forage Yield of Different Fall Dormancy Rating Alfalfa Cultivars in a Semiarid Climate." Agricultural Research 10, no. 3: 378-389.

Journal article
Published: 26 February 2021 in Sustainability
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Fruit and nut trees production is an important activity across the southwest United States and this production is greatly impacted by the local climate. Temperature is the main environmental factor influencing the growth and the productivity of the fruit and nut trees as it affects the trees’ physiology and the vulnerability of flower bud, flowers, and young fruit and nut to the low temperatures or spring frost. The objective of the present study is to estimate the chilling and heat accumulation of fruit and nut trees across New Mexico. Three study sites as Fabian Garcia, Los Lunas, and Farmington were considered and climate variables were collected at hourly time step. The Utah model and the Dynamic model were used to estimate the accumulated chilling while the Forcing model was used for the heat accumulation. The possible fruit and nut trees endodormancy and ecodormancy periods were also determined at the study sites. The results obtained chilling hours of 715 ± 86.60 h at Fabian Garcia, 729.53 ± 41.71 h at Los Lunas, and 828.95 ± 83.73 h at Farmington using the Utah model. The accumulated chill portions during trees’ endodormancy was 3.12 ± 3.05 CP at Fabian Garcia, 42.23 ± 5.08 CP at Los Lunas, and 56.14 ± 1.84 CP at Farmington. The accumulated heat was 8735.52 ± 1650.91 GDH at Fabian Garcia, 7695.43 ± 212.90 GDH at Los Lunas, and 5984.69 ± 2353.20 GDH at Farmington. The fruit and nut trees are at no risk of bud flowers vulnerability at Fabian Garcia while they are under high risk of bud flowers and or young fruit and nut vulnerability to low temperatures early spring as hourly temperature can still drop below 0 °C in April at the end of ecodormancy and flower blooming and young fruits and nuts development stage at Los Lunas and Farmington. Severe weather, especially frost conditions during winter and early spring, can be a significant threat to sustainable nut and fruit production in the northern New Mexico while high chilling requirement fruit and nut trees might not meet chill requirements in the southern New Mexico.

ACS Style

Koffi Djaman; Komlan Koudahe; Murali Darapuneni; Suat Irmak. Chilling and Heat Accumulation of Fruit and Nut Trees and Flower Bud Vulnerability to Early Spring Low Temperatures in New Mexico: Meteorological Approach. Sustainability 2021, 13, 2524 .

AMA Style

Koffi Djaman, Komlan Koudahe, Murali Darapuneni, Suat Irmak. Chilling and Heat Accumulation of Fruit and Nut Trees and Flower Bud Vulnerability to Early Spring Low Temperatures in New Mexico: Meteorological Approach. Sustainability. 2021; 13 (5):2524.

Chicago/Turabian Style

Koffi Djaman; Komlan Koudahe; Murali Darapuneni; Suat Irmak. 2021. "Chilling and Heat Accumulation of Fruit and Nut Trees and Flower Bud Vulnerability to Early Spring Low Temperatures in New Mexico: Meteorological Approach." Sustainability 13, no. 5: 2524.

Review
Published: 01 February 2021 in Sustainability
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Limited water resources coupled with the increase of the human population calls for more efficient use of water in irrigated agriculture. Potato (Solanum tuberosum L.) is one of the most widely grown crops worldwide and is very sensitive to water stress due to its shallow rooting system. With the dilemma of potato sensitivity to drought and limited available water resources restricting crop production, researchers and crop growers have been investigating different approaches for optimizing potato yield and improving crop water use efficiency under different irrigation methods. While potato response to water is affected by other management practices such as fertilizer management, the present review is focused on the potato response to water under different environments and different irrigation methods and the impact on potato quality and potato diseases. Variable results obtained from research studies indicate the non-transferability of the results from one location to another as potato cultivars are not the same and potato breeders are still making effort to develop new high-yielding varieties to increase crop production and or develop new varieties for a specific trait to satisfy consumers exigence. This review is a valuable source of information for potato growers and scientists as it is not only focused on the impact of irrigation regimes on potato yield and water productivity as most reviews on water management, but it also presents the impact of irrigation regime on diseases in potatoes, tuber specific gravity, metabolite content of the tubers and the quality of the processed potato products.

ACS Style

Koffi Djaman; Suat Irmak; Komlan Koudahe; Samuel Allen. Irrigation Management in Potato (Solanum tuberosum L.) Production: A Review. Sustainability 2021, 13, 1504 .

AMA Style

Koffi Djaman, Suat Irmak, Komlan Koudahe, Samuel Allen. Irrigation Management in Potato (Solanum tuberosum L.) Production: A Review. Sustainability. 2021; 13 (3):1504.

Chicago/Turabian Style

Koffi Djaman; Suat Irmak; Komlan Koudahe; Samuel Allen. 2021. "Irrigation Management in Potato (Solanum tuberosum L.) Production: A Review." Sustainability 13, no. 3: 1504.

Journal article
Published: 02 December 2020 in Climate
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The objective of this study is to perform trend analysis in the historic data sets of annual and crop season [May–September] precipitation and daily maximum and minimum temperatures across the southwest United States. Eighteen ground-based weather stations were considered across the southwest United States for a total period from 1902 to 2017. The non-parametric Mann–Kendall test method was used for the significance of the trend analysis and the Sen’s slope estimator was used to derive the long-term average rates of change in the parameters. The results showed a decreasing trend in annual precipitation at 44.4% of the stations with the Sen’s slopes varying from −1.35 to −0.02 mm/year while the other stations showed an increasing trend. Crop season total precipitation showed non-significant variation at most of the stations except two stations in Arizona. Seventy-five percent of the stations showed increasing trend in annual maximum temperature at the rates that varied from 0.6 to 3.1 °C per century. Air cooling varied from 0.2 to 1.0 °C per century with dominant warming phenomenon at the regional scale of the southwest United States. Average annual minimum temperature had increased at 69% of the stations at the rates that varied from 0.1 to 8 °C over the last century, while the annual temperature amplitude showed a decreasing trend at 63% of stations. Crop season maximum temperature had significant increasing trend at 68.8% of the stations at the rates varying from 0.7 to 3.5 °C per century, while the season minimum temperature had increased at 75% of the stations.

ACS Style

Koffi Djaman; Komlan Koudahe; Ansoumana Bodian; Lamine Diop; Papa Malick Ndiaye. Long-Term Trend Analysis in Annual and Seasonal Precipitation, Maximum and Minimum Temperatures in the Southwest United States. Climate 2020, 8, 142 .

AMA Style

Koffi Djaman, Komlan Koudahe, Ansoumana Bodian, Lamine Diop, Papa Malick Ndiaye. Long-Term Trend Analysis in Annual and Seasonal Precipitation, Maximum and Minimum Temperatures in the Southwest United States. Climate. 2020; 8 (12):142.

Chicago/Turabian Style

Koffi Djaman; Komlan Koudahe; Ansoumana Bodian; Lamine Diop; Papa Malick Ndiaye. 2020. "Long-Term Trend Analysis in Annual and Seasonal Precipitation, Maximum and Minimum Temperatures in the Southwest United States." Climate 8, no. 12: 142.

Journal article
Published: 13 July 2020 in Agriculture
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The highly variable weather under changing climate conditions affects the establishment and the cutoff of crop growing season and exposes crops to failure if producers choose non-adapted relative maturity that matches the characteristics of the crop growing season. This study aimed to determine the relationship between maize hybrid relative maturity and the grain yield and determine the relative maturity range that will sustain maize production in northwest New Mexico (NM). Different relative maturity maize hybrids were grown at the Agricultural Science Center at Farmington ((Latitude 36.69° North, Longitude 108.31° West, elevation 1720 m) from 2003 to 2019 under sprinkler irrigation. A total of 343 hybrids were grouped as early and full season hybrids according to their relative maturity that ranged from 93 to 119 and 64 hybrids with unknown relative maturity. The crops were grown under optimal management condition with no stress of any kind. The results showed non-significant increase in grain yield in early season hybrids and non-significant decrease in grain yield with relative maturity in full season hybrids. The relative maturity range of 100–110 obtained reasonable high grain yields and could be considered under the northwestern New Mexico climatic conditions. However, more research should target the evaluation of different planting date coupled with plant population density to determine the planting window for the early season and full season hybrids for the production optimization and sustainability.

ACS Style

Koffi Djaman; Curtis Owen; Margaret West; Samuel Allen; Komlan Koudahe; Murali Darapuneni; Michael O’Neill. Relationship between Relative Maturity and Grain Yield of Maize (Zea mays L.) Hybrids in Northwest New Mexico for the 2003–2019 Period. Agriculture 2020, 10, 290 .

AMA Style

Koffi Djaman, Curtis Owen, Margaret West, Samuel Allen, Komlan Koudahe, Murali Darapuneni, Michael O’Neill. Relationship between Relative Maturity and Grain Yield of Maize (Zea mays L.) Hybrids in Northwest New Mexico for the 2003–2019 Period. Agriculture. 2020; 10 (7):290.

Chicago/Turabian Style

Koffi Djaman; Curtis Owen; Margaret West; Samuel Allen; Komlan Koudahe; Murali Darapuneni; Michael O’Neill. 2020. "Relationship between Relative Maturity and Grain Yield of Maize (Zea mays L.) Hybrids in Northwest New Mexico for the 2003–2019 Period." Agriculture 10, no. 7: 290.

Journal article
Published: 10 July 2020 in Water
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Understanding evapotranspiration and its long-term trends is essential for water cycle studies, modeling and for water uses. Spatial and temporal analysis of evapotranspiration is therefore important for the management of water resources, particularly in the context of climate change. The objective of this study is to analyze the trend of reference evapotranspiration (ET0) as well as its sensitivity to climatic variables in the Senegal River basin. Mann-Kendall’s test and Sen’s slope were used to detect trends and amplitude changes in ET0 and climatic variables that most influence ET0. Results show a significant increase in annual ET0 for 32% of the watershed area over the 1984–2017 period. A significant decrease in annual ET0 is observed for less than 1% of the basin area, mainly in the Sahelian zone. On a seasonal scale, ET0 increases significantly for 32% of the basin area during the dry season and decreases significantly for 4% of the basin during the rainy season. Annual maximum, minimum temperatures and relative humidity increase significantly for 68%, 81% and 37% of the basin, respectively. However, a significant decrease in wind speed is noted in the Sahelian part of the basin. The wind speed decrease and relative humidity increase lead to the decrease in ET0 and highlight a “paradox of evaporation” in the Sahelian part of the Senegal River basin. Sensitivity analysis reveals that, in the Senegal River basin, ET0 is more sensitive to relative humidity, maximum temperature and solar radiation.

ACS Style

Papa Malick Ndiaye; Ansoumana Bodian; Lamine Diop; Abdoulaye Deme; Alain Dezetter; Koffi Djaman; Andrew Ogilvie. Trend and Sensitivity Analysis of Reference Evapotranspiration in the Senegal River Basin Using NASA Meteorological Data. Water 2020, 12, 1957 .

AMA Style

Papa Malick Ndiaye, Ansoumana Bodian, Lamine Diop, Abdoulaye Deme, Alain Dezetter, Koffi Djaman, Andrew Ogilvie. Trend and Sensitivity Analysis of Reference Evapotranspiration in the Senegal River Basin Using NASA Meteorological Data. Water. 2020; 12 (7):1957.

Chicago/Turabian Style

Papa Malick Ndiaye; Ansoumana Bodian; Lamine Diop; Abdoulaye Deme; Alain Dezetter; Koffi Djaman; Andrew Ogilvie. 2020. "Trend and Sensitivity Analysis of Reference Evapotranspiration in the Senegal River Basin Using NASA Meteorological Data." Water 12, no. 7: 1957.

Journal article
Published: 16 June 2020 in Water
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Alfalfa is one of the most nutritive and high-yielding forage legumes planted in rotation with cereal crops across the United States. Under semiarid and arid climates with limited water resources, sustainable management of the available resources is required. The objective of this study was to investigate the effect of different irrigation regimes and fungicide applications on alfalfa in the high desert region of the Colorado Plateau of the U.S. Field experiments were conducted during the 2012–2014 period. Alfalfa was planted in fall 2012, uniformly irrigated for crop establishment and subjected to seven different irrigation regimes after the first cut in spring 2013. Alfalfa was treated by fungicide application and was harvested at 10% blooming. The maximum amounts of applied water were 350, 300, 208, and 312 mm, respectively, during the first, second, third, and fourth regrowth cycles in 2013, and 373, 282, 198, and 246 mm in 2014 for the respective regrowth cycles in 2014; the seasonal applied irrigation amount varied from 711 to 1171 mm in 2013 and from 328 to 1100 mm in 2014. The results showed non-significant effect of fungicide application on the forage yield. Alfalfa forage yield was significantly affected by the irrigation regimes and showed a third order polynomial relationship with the applied irrigation amounts during each regrowth cycle and on seasonal scale. Forage yield decreased from the first cut to the fourth cut and the annual forage varied from 10.6 to 25.7 Mg/ha for the treated alfalfa and from 11.5 to 25.6 Mg/ha for the non-treated alfalfa. Forage yield at each cut accounted for 39.6, 24.2, 17.6, and 18.6% of the 2013 season forage yield and 31.4, 23.8, 21.6, and 23.2% of the 2014 season forage yield, for the first, second, third, and fourth cut, respectively. Alfalfa water use efficiency varied from 0.06 to 3.3 kg/m3. The relationships developed in this study could be used by forage growers, crop consultants, and project managers for decision making and planning to improve the productivity of water under the semiarid and arid climate of New Mexico and the surrounding regions.

ACS Style

Koffi Djaman; Daniel Smeal; Komlan Koudahe; Samuel Allen. Hay Yield and Water Use Efficiency of Alfalfa under Different Irrigation and Fungicide Regimes in a Semiarid Climate. Water 2020, 12, 1721 .

AMA Style

Koffi Djaman, Daniel Smeal, Komlan Koudahe, Samuel Allen. Hay Yield and Water Use Efficiency of Alfalfa under Different Irrigation and Fungicide Regimes in a Semiarid Climate. Water. 2020; 12 (6):1721.

Chicago/Turabian Style

Koffi Djaman; Daniel Smeal; Komlan Koudahe; Samuel Allen. 2020. "Hay Yield and Water Use Efficiency of Alfalfa under Different Irrigation and Fungicide Regimes in a Semiarid Climate." Water 12, no. 6: 1721.

Journal article
Published: 28 April 2020 in Hydrology
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Reference evapotranspiration (ET0) is a key element of the water cycle in tropical areas for the planning and management of water resources, hydrological modeling, and irrigation management. The objective of this research is to assess twenty methods in computing ET0 in the Senegal River Basin and to calibrate and validate the best methods that integrate fewer climate variables. The performance of alternative methods compared to the Penman Monteith (FAO56-PM) model is evaluated using the coefficient of determination (R2), normalized root mean square error (NRMSE), percentage of bias (PBIAS), and the Kling–Gupta Efficiency (KGE). The most robust methods integrating fewer climate variables were calibrated and validated and the results show that Trabert, Valiantzas 2, Valiantzas 3, and Hargreaves and Samani models are, respectively, the most robust for ET0 estimation. The calibration improves the estimates of reference evapotranspiration compared to original models. It improved the performance of these models with an increase in KGE values of 45%, 32%, 29%, and 19% for Trabert, Valiantzas 2, Valiantzas 3, and Hargreaves and Samani models, respectively. From a spatial point of view, the calibrated models of Trabert and Valiantzas 2 are robust in all the climatic zones of the Senegal River Basin, whereas, those of Valiantzas 3 and Hargreaves and Samani are more efficient in the Guinean zone. This study provides information on the choice of a model for estimating evapotranspiration in the Senegal River Basin.

ACS Style

Papa Malick Ndiaye; Ansoumana Bodian; Lamine Diop; Abdoulaye Deme; Alain Dezetter; Koffi Djaman. Evaluation and Calibration of Alternative Methods for Estimating Reference Evapotranspiration in the Senegal River Basin. Hydrology 2020, 7, 24 .

AMA Style

Papa Malick Ndiaye, Ansoumana Bodian, Lamine Diop, Abdoulaye Deme, Alain Dezetter, Koffi Djaman. Evaluation and Calibration of Alternative Methods for Estimating Reference Evapotranspiration in the Senegal River Basin. Hydrology. 2020; 7 (2):24.

Chicago/Turabian Style

Papa Malick Ndiaye; Ansoumana Bodian; Lamine Diop; Abdoulaye Deme; Alain Dezetter; Koffi Djaman. 2020. "Evaluation and Calibration of Alternative Methods for Estimating Reference Evapotranspiration in the Senegal River Basin." Hydrology 7, no. 2: 24.

Journal article
Published: 01 February 2020 in Journal of Irrigation and Drainage Engineering
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ACS Style

Koffi Djaman; Komlan Koudahe. Discussion of “Response of Taro to Varying Water Regimes and Soil Textures” by Meiling Li, Angélica Cristina Fernandes Deus, and Lin Chau Ming. Journal of Irrigation and Drainage Engineering 2020, 146, 07019012 .

AMA Style

Koffi Djaman, Komlan Koudahe. Discussion of “Response of Taro to Varying Water Regimes and Soil Textures” by Meiling Li, Angélica Cristina Fernandes Deus, and Lin Chau Ming. Journal of Irrigation and Drainage Engineering. 2020; 146 (2):07019012.

Chicago/Turabian Style

Koffi Djaman; Komlan Koudahe. 2020. "Discussion of “Response of Taro to Varying Water Regimes and Soil Textures” by Meiling Li, Angélica Cristina Fernandes Deus, and Lin Chau Ming." Journal of Irrigation and Drainage Engineering 146, no. 2: 07019012.

Journal article
Published: 19 January 2020 in Agronomy
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Alfalfa is one of the most important, nutritive, and high yielding forage legumes planted across the US. Fall dormancy in alfalfa influences forage yield characteristics and the plants persistence mostly under the cold and temperate climate. The objective of this study was to evaluate alfalfa cultivars with different fall dormancy-ratings for their forage yield at each cut and the annual forage yield. Two sets of 24 alfalfa cultivars were evaluated in a field experiment conducted at the Agricultural Science Center at Farmington, NM. The first set of 24 cultivars was planted late fall 2007 at seeding rate of 22.4 kg ha−1 and managed for the 2007–2011 period and the second set was planted late fall 2009 and managed during the 2009–2013 period. Average forage yield varied with years from 7.6 to 2.9 Mg ha−1, 6.8 to 4.3 Mg ha−1, 9.2 to 4.2 Mg ha−1, and 7.9 to 3.2 Mg ha−1 during the 1st, 2nd, 3rd, and 4th alfalfa cut, respectively. The results showed no statistical differences between the moderately dormant, dormant, and the non-dormant alfalfa cultivars while they showed higher forage yield than the very dormant and semi-dormant alfalfa cultivars. There was a decreasing trend in forage yield from the first cut to the fourth cut in each growing season. However, the very dormant cultivars showed the lowest forage yield. Alfalfa forage yield decreased from the cut 1 to the cut 4 which represented on average 33, 29, 22, and 16% of the annual yield. The semi-dormant cultivars obtained the lowest forage yield at the first and second cutting while there was no difference between the cultivars for the third and fourth harvests. Average forage yields per harvest were 5.7, 5.9, 6.0, 5.5, and 5.9 Mg ha−1 for the very dormant, dormant, moderately dormant, semi-dormant, and non-dormant alfalfa cultivars, respectively. Annual forage yield varied with alfalfa fall dormancy-ratings and ranged from 15.5 to 29.9 Mg ha−1 with the highest forage yield achieved during the third years of the production. The moderately dormant and the non-dormant cultivars showed the highest yield during the first harvest year while the very dormant cultivars and dormant cultivars had the lowest forage yield. Alfalfa cultivars with a fall dormancy range 4–5 may be considered for alfalfa production in northwest New Mexico however, the good agricultural practices (conservation tillage, fertilizer management based on soil residual available nutrient and crop requirement, recommended planting rate, weed and pest management, irrigation scheduling to match crop evapotranspiration) should be the most important to maximize alfalfa forage yield in the southwest US.

ACS Style

Koffi Djaman; Curtis Owen; Komlan Koudahe; Michael O’Neill. Evaluation of Different Fall Dormancy-Rating Alfalfa Cultivars for Forage Yield in a Semiarid Environment. Agronomy 2020, 10, 146 .

AMA Style

Koffi Djaman, Curtis Owen, Komlan Koudahe, Michael O’Neill. Evaluation of Different Fall Dormancy-Rating Alfalfa Cultivars for Forage Yield in a Semiarid Environment. Agronomy. 2020; 10 (1):146.

Chicago/Turabian Style

Koffi Djaman; Curtis Owen; Komlan Koudahe; Michael O’Neill. 2020. "Evaluation of Different Fall Dormancy-Rating Alfalfa Cultivars for Forage Yield in a Semiarid Environment." Agronomy 10, no. 1: 146.

Journal article
Published: 19 December 2019 in Insects
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Potato psyllid (Bactericera cockerelli) is one of the most important pests in potatoes (Solanum tuberosum L.) due to its feeding behavior and the transmission of a bacterium (Candidatus Liberibacter solanacearum) that causes zebra chip disease, altering the quality of the potato tuber and the fried potato chip or french fry. This pest is thus a threat to the chip potato industry and often requires preventive measures including the use of costly insecticides. The objectives of this research were to monitor the variation in B. cockerelli adult abundance and to evaluate the risk of zebra chip disease in northwestern New Mexico, USA. Yellow sticky traps were used to collect the pest at the Agricultural Experiment Station at Farmington, NM and in nearby commercial fields at the Navajo Agricultural Products Industry (NAPI) and Navajo Mesa Farms during the 2017–2019 period. The collected adult pests were analyzed at Texas A & M University for the presence of Candidatus L. solanacearum (Lso). The results showed field infestation by B. cockerelli in early June and that the population peaked during the second half of July and decreased as the potato growing season progressed. However, a second less important peak of the pest was revealed around mid- to late-August, depending on the growing season and field. While the B. cockerelli population increased linearly with average air temperature, it showed strong third order polynomial relationships with the accumulated thermal units and the Julian days. The test of B. cockerelli for the Lso infection revealed a low incidence of the pathogen varying from 0.22% to 6.25% and the infected adult B. cockerelli were collected during the population peak period. The results of this study may be helpful to potato growers in pest management decision-making and control. However, more study is needed to evaluate zebra chip disease in terms of its prevention and economic impact, and to develop economic thresholds and pest management programs for northwestern New Mexico and neighboring regions.

ACS Style

Koffi Djaman; Charles Higgins; Shantel Begay; Komlan Koudahe; Samuel Allen; Kevin Lombard; Michael O’Neill. Seasonal Occurrence of Potato Psyllid (Bactericera Cockerelli) and Risk of Zebra Chip Pathogen (Candidatus Liberibacter Solanacearum) in Northwestern New Mexico. Insects 2019, 11, 3 .

AMA Style

Koffi Djaman, Charles Higgins, Shantel Begay, Komlan Koudahe, Samuel Allen, Kevin Lombard, Michael O’Neill. Seasonal Occurrence of Potato Psyllid (Bactericera Cockerelli) and Risk of Zebra Chip Pathogen (Candidatus Liberibacter Solanacearum) in Northwestern New Mexico. Insects. 2019; 11 (1):3.

Chicago/Turabian Style

Koffi Djaman; Charles Higgins; Shantel Begay; Komlan Koudahe; Samuel Allen; Kevin Lombard; Michael O’Neill. 2019. "Seasonal Occurrence of Potato Psyllid (Bactericera Cockerelli) and Risk of Zebra Chip Pathogen (Candidatus Liberibacter Solanacearum) in Northwestern New Mexico." Insects 11, no. 1: 3.

Journal article
Published: 24 October 2019 in Insects
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This study was conducted to monitor the population dynamics of six major insect pests at the NMSU Agricultural Science Center at Farmington (ASC-Farmington) and within an adjacent commercial farm (Navajo Agricultural Products Industry, NAPI) for more effective and efficient pest management during the 2013–2019 period. Specific pheromone traps, sticky and net traps were used to collects moths of beet armyworm (Spodoptera exigua), cabbage looper (Trichoplusia ni), corn earworm (Helicoverpa zea), fall armyworm (Spodoptera frugiperda), potato psyllid (Bactericera cockerelli), and western bean cutworm (Striacosta albicosta). These insects generally appear in early June and their population decreases toward the end of August/early September with different peak times and magnitudes during July and August. Bactericera cockerelli was not substantially present in the commercial farm due to intensive insecticide application. Overall, all six insect species were present at ASC-Farmington, with relative abundance, in percent of the total collected moths by all traps, varying from 6.5 to 19% for Trichoplusia ni, 16 to 29.2% for Spodoptera exigua, 1.5 to 20.6% for Striacosta albicosta, 10 to 25% for Helicoverpa zea, 18.5 to 25.6% for Spodoptera frugiperda and 8.5 to 26.9% for Bactericera cockerelli. In NAPI’s commercial field, while the potato psyllid Bactericera cockerelli was not recorded, Trichoplusia ni and Spodoptera exigua showed decreasing rates that varied from 27.5 to 4.2% and from 49.3 to 7.8%, respectively. Striacosta albicosta, Helicoverpa zea and Spodoptera exigua showed increasing rates varying from 2.9 to 28%, from 7.8 to 25.3% and from 10.9 to 52%, respectively. The results of this study could serve as a guideline for sustainable management strategies for each of the six species for production profitability.

ACS Style

Koffi Djaman; Charles Higgins; Michael O’Neill; Shantel Begay; Komlan Koudahe; Samuel Allen; O’ Neill. Population Dynamics of Six Major Insect Pests During Multiple Crop Growing Seasons in Northwestern New Mexico. Insects 2019, 10, 369 .

AMA Style

Koffi Djaman, Charles Higgins, Michael O’Neill, Shantel Begay, Komlan Koudahe, Samuel Allen, O’ Neill. Population Dynamics of Six Major Insect Pests During Multiple Crop Growing Seasons in Northwestern New Mexico. Insects. 2019; 10 (11):369.

Chicago/Turabian Style

Koffi Djaman; Charles Higgins; Michael O’Neill; Shantel Begay; Komlan Koudahe; Samuel Allen; O’ Neill. 2019. "Population Dynamics of Six Major Insect Pests During Multiple Crop Growing Seasons in Northwestern New Mexico." Insects 10, no. 11: 369.

Article
Published: 05 June 2019 in Paddy and Water Environment
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Soil salinity is a threat to crop production in the Senegal River Delta where salt intrusion increases soil electrical conductivity and most of farmers had abandoned their rice farms. The objective of this study was to evaluate an integrated management to improve rice productivity under saline soil condition in the Senegal River Delta. Field experiments were conducted during four rice-growing seasons from July 2014 to July 2016 at Africa Rice Center research station at Ndiaye, Senegal. The performance of five rice genotypes (IR63275-B-1-1-3-3-2, WAS73-B-B-231-4, NERICA-L9, FL478, and IR29) was evaluated under three salinity levels (0.5–0.8 dS m−1, 2.0 dS m−1, 3.5 dS m−1) and two fertilizer management options (basal dressing at 100 kg ha−1 of N–P–K (15–15–15) only and basal dressing at 200 kg ha−1 of N–P–K (15–15–15) + 50 kg N ha−1 urea at panicle initiation and at booting. Rice seedlings were raised at nursery for 21 days and transplanted at the density of 20 cm × 20 cm around March 15 and August 15 and harvested around July 15 and early December. The plots were drained canal when soil EC increased 0.1 dS m−1 above the designed EC levels. The results showed that rice yield decreased with the increasing soil salinity and were season dependent. Rice grain yield varied from 0.9 to 8 tons ha−1. Rice grain yield was 20% higher during the hot and dry seasons than the wet season. The application of the recommended fertilizer improved rice yield by 52% compared to the basal fertilizer application only. Nitrogen application at panicle initiation and at booting stages in addition to the basal fertilizer application doubled rice grain yield and should be adopted under salinity condition across the Senegal River Delta. The analysis of the combination of yield index, yield stability index, stress susceptibility index and the stress tolerant index indicated that the newly developed rice genotypes IR63275-B-1-1-3-3-2 and WAS73-B-B-231-4 showed high salt tolerance with better yield stability and low stress susceptibility and constitute good candidate to be adopted under the best fertilizer management option in the Senegal River Delta climate, soil salinity and similar environmental conditions.

ACS Style

Koffi Djaman; Valere Mel; Amith Boye; Lamine Diop; Baboucarr Manneh; Raafat El-Namaky; Komlan Koudahe; Koichi Futakuchi. Rice genotype and fertilizer management for improving rice productivity under saline soil conditions. Paddy and Water Environment 2019, 18, 43 -57.

AMA Style

Koffi Djaman, Valere Mel, Amith Boye, Lamine Diop, Baboucarr Manneh, Raafat El-Namaky, Komlan Koudahe, Koichi Futakuchi. Rice genotype and fertilizer management for improving rice productivity under saline soil conditions. Paddy and Water Environment. 2019; 18 (1):43-57.

Chicago/Turabian Style

Koffi Djaman; Valere Mel; Amith Boye; Lamine Diop; Baboucarr Manneh; Raafat El-Namaky; Komlan Koudahe; Koichi Futakuchi. 2019. "Rice genotype and fertilizer management for improving rice productivity under saline soil conditions." Paddy and Water Environment 18, no. 1: 43-57.

Journal article
Published: 14 February 2019 in Agricultural Water Management
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Recognition and understanding of impacts of any crop and (or) soil management practice on crop water use is equally crucial as its intended impacts. One such practice that has gained adoption among producers in the U.S. maize growing regions is conservation tillage, aiming at maintaining about 30–40%, or more, of residual vegetative cover on the soil surface after planting. The presence of numerous interacting factors suggests that the success of this practice is subject to its effectiveness on local scales, requiring scientific/research-based data. The crop evapotranspiration (ETc), microclimate, yield, water productivity (WP) and other variables for irrigated maize (Zea mays L.) were measured and compared under disk-till (DT) (conventional) and no-till (NT) (conservation) tillage systems in 2011, 2012 and 2013 in two carefully managed and monitored producers’ fields, which have been under these tillage management practices for over 17 years. On a three-year total basis, the DT maize ETc (2091 mm) was 92 mm higher than the NT maize ETc (1999 mm). Also, a seasonal and a monthly pattern existed in the difference between DT and NT ETc. NT maize had less pre-anthesis water use than DT maize and greater post-anthesis water use than DT maize in all three growing seasons. The irrigation-yield (IYPF) and evapotranspiration-yield production functions (ETYPF) were developed, and change in ETc increase per unit irrigation application was quantified for both DT and NT maize. Differences in ETc between the two tillage systems was also responsible for modification of field-scale microclimate, where the difference in ETc between the two fields was negatively related to differences in air temperature, vapor pressure deficit, wind speed and sensible heat flux, whereas it was positively related to net radiation and total soil-water. Maize yield was higher for DT maize than NT maize for all three years, by 7% (0.8 t/ha), 6% (0.8 t/ha) and 10% (1.2 t/ha) for 2011, 2012 and 2013, respectively. Tillage practice did not impact WP as WP for both tillage practices were similar, ranging from 1.74 to 1.94 kg/m3. The presented research data and information are a benchmark evidence for tillage-specific agricultural water management for stakeholders in regions with similar crop management and climatic conditions.

ACS Style

Suat Irmak; Meetpal Kukal; Ali Mohammed; Koffi Djaman. Disk-till vs. no-till maize evapotranspiration, microclimate, grain yield, production functions and water productivity. Agricultural Water Management 2019, 216, 177 -195.

AMA Style

Suat Irmak, Meetpal Kukal, Ali Mohammed, Koffi Djaman. Disk-till vs. no-till maize evapotranspiration, microclimate, grain yield, production functions and water productivity. Agricultural Water Management. 2019; 216 ():177-195.

Chicago/Turabian Style

Suat Irmak; Meetpal Kukal; Ali Mohammed; Koffi Djaman. 2019. "Disk-till vs. no-till maize evapotranspiration, microclimate, grain yield, production functions and water productivity." Agricultural Water Management 216, no. : 177-195.

Journal article
Published: 01 January 2019 in Journal of Irrigation and Drainage Engineering
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The adoption of the Penman-Monteith reference evapotranspiration (ETo) method necessitates the use of climatic data and parameters measured above a reference surface (e.g., reference grass), which is rarely available across agro-ecosystems in all countries. In such cases, alternatively, climate data collected above other vegetation surfaces can be potential sources of data for ETo estimations. The objective of this study was to determine whether microclimatic data measured above irrigated lowland rice can be used in estimating ETo using the Penman-Monteith model in conditions where climatic data measured in reference weather stations do not exist. Maximum and minimum air temperatures (Tmax and Tmin, respectively) and maximum and minimum relative humidity (RHmax and RHmin, respectively) were measured above a rice canopy in 2014, 2015, and 2016, when a full data set was also collected above well-maintained grass canopy, which was 100 m from the rice research plots. Daily average Tmin and Tmax for rice and Tmin and Tmax for grass were linearly and strongly correlated with regression slopes of 1.0085 and 0.9829, R2 greater than 0.83, and root-mean square error (RMSE) of 1.30 and 1.53°C for Tmin and Tmax, respectively. Dew point temperature (Td) varied from −3.73 to 33.44°C over grass and from −0.96 to 34.26°C above rice canopy, with an average of 19.32 and 21.10°C above grass and rice, respectively. The observed RMSE and mean bias error (MBE) for RHmax and RHmin were 4.1% and 4.8% and 2.2% and 4.1%, respectively. The relative humidity difference of 3.2% was observed above the rice canopy. RHmin, RHmax, and RHmean measured over the rice canopy were linearly correlated with those measured over grass with regression slopes of 1.13, 1.03, and 1.06, respectively, and R2 values of 0.98, 0.96, and 0.98, respectively. The vapor pressure deficit (VPD) difference was 9.4% greater over the grass canopy and averaged 2.15 kPa, while it averaged 1.97 kPa over rice with a very low RMSE of 0.27 kPa between VPD values measured above the two surfaces. The estimated net radiation (Rn) values above grass and rice canopies were highly correlated, with a regression slope of 1.017, R2 of 0.9976 and a RMSE as low as 0.25 MJ/m2, which would result in only 0.1 mm/d of water. Daily ETo computed using the weather data measured above grass and flooded rice canopies showed that daily ETo-grass varied from 1.66 to 10.78 mm and averaged 5.38 mm. Similarly, daily ETo-rice varied from 1.53 to 10.16 mm, averaging 5.21 mm. The MBE between ETo-grass and ETo-rice was 0.17 mm/day and the RMSE was as low as 0.24 mm/day, representing a relative error of only 4.5%. There was strong agreement between ETo-rice and ETo-grass and the simple linear regression slope between ETo-rice and ETo-grass was 0.943, 0.966, and 0.977 in 2014, 2015, and 2016, respectively, with an R2≥0.98. Overall, it was determined that ETo-rice=0.9687 ETo-grass with an R2 of 0.99. The good fit between...

ACS Style

Koffi Djaman; Mamadou Sall; Abdoulaye Sow; Baboucarr Manneh; Suat Irmak. Impact of Air Temperature and Relative Humidity Measured over Rice and Grass Canopies on Penman-Monteith Reference Evapotranspiration Estimates. Journal of Irrigation and Drainage Engineering 2019, 145, 06018008 .

AMA Style

Koffi Djaman, Mamadou Sall, Abdoulaye Sow, Baboucarr Manneh, Suat Irmak. Impact of Air Temperature and Relative Humidity Measured over Rice and Grass Canopies on Penman-Monteith Reference Evapotranspiration Estimates. Journal of Irrigation and Drainage Engineering. 2019; 145 (1):06018008.

Chicago/Turabian Style

Koffi Djaman; Mamadou Sall; Abdoulaye Sow; Baboucarr Manneh; Suat Irmak. 2019. "Impact of Air Temperature and Relative Humidity Measured over Rice and Grass Canopies on Penman-Monteith Reference Evapotranspiration Estimates." Journal of Irrigation and Drainage Engineering 145, no. 1: 06018008.

Original paper
Published: 17 September 2018 in Theoretical and Applied Climatology
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Reference evapotranspiration (ETo) is an important parameter in hydrological, agricultural, and environmental studies. Accurate estimation of ETo helps to improve water management and increase water productivity and efficiency. While the Penman-Monteith ETo equation enjoys worldwide adoption as the most accurate ETo equation, the number of requested climatic variables makes its application very questionable under limited data conditions. The objective of this study was to evaluate the Penman-Monteith ETo equation under limited climatic data and 34 simple ETo equations that request few climatic variables. Five weather stations were considered under the semiarid and dry climate across New Mexico for the period of 2009–2017. The Penman-Monteith ETo equation showed good performance under missing solar radiation, relative humidity, and wind speed and could still be adapted under limited data conditions across New Mexico. However, it tended to underestimate daily ETo when more than one climatic variable data is missing. Among the simple ETo equations, four of the Valiantzas equations, along with the Makkink, Calibrated Hargreaves, Abtew, Jensen-Haise, and Caprio equations, were the best performing ones compared to the Penman-Monteith equation and could be the best alternative ETo estimation methods. These alternative equations could be used by irrigation managers, producers, engineers, and university researchers to improve water management across the dry semiarid and arid zone across New Mexico, as well as other semiarid areas where water is the most limiting factor to food and fiber production.

ACS Style

Koffi Djaman; Michael O’Neill; Lamine Diop; Ansoumana Bodian; Samuel Allen; Komlan Koudahe; Kevin Lombard. Evaluation of the Penman-Monteith and other 34 reference evapotranspiration equations under limited data in a semiarid dry climate. Theoretical and Applied Climatology 2018, 137, 729 -743.

AMA Style

Koffi Djaman, Michael O’Neill, Lamine Diop, Ansoumana Bodian, Samuel Allen, Komlan Koudahe, Kevin Lombard. Evaluation of the Penman-Monteith and other 34 reference evapotranspiration equations under limited data in a semiarid dry climate. Theoretical and Applied Climatology. 2018; 137 (1-2):729-743.

Chicago/Turabian Style

Koffi Djaman; Michael O’Neill; Lamine Diop; Ansoumana Bodian; Samuel Allen; Komlan Koudahe; Kevin Lombard. 2018. "Evaluation of the Penman-Monteith and other 34 reference evapotranspiration equations under limited data in a semiarid dry climate." Theoretical and Applied Climatology 137, no. 1-2: 729-743.

Journal article
Published: 01 July 2018 in Journal of Irrigation and Drainage Engineering
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Koffi Djaman. Closure to “Evaluation of Valiantzas’ Simplified Forms of the FAO-56 Penman-Monteith Reference Evapotranspiration Model in a Humid Climate” by Koffi Djaman, Daran Rudnick, Valere C. Mel, Denis Mutiibwa, Lamine Diop, Mamadou Sall, Isa Kabenge, Ansoumana Bodian, Hossein Tabari, and Suat Irmak. Journal of Irrigation and Drainage Engineering 2018, 144, 07018027 .

AMA Style

Koffi Djaman. Closure to “Evaluation of Valiantzas’ Simplified Forms of the FAO-56 Penman-Monteith Reference Evapotranspiration Model in a Humid Climate” by Koffi Djaman, Daran Rudnick, Valere C. Mel, Denis Mutiibwa, Lamine Diop, Mamadou Sall, Isa Kabenge, Ansoumana Bodian, Hossein Tabari, and Suat Irmak. Journal of Irrigation and Drainage Engineering. 2018; 144 (7):07018027.

Chicago/Turabian Style

Koffi Djaman. 2018. "Closure to “Evaluation of Valiantzas’ Simplified Forms of the FAO-56 Penman-Monteith Reference Evapotranspiration Model in a Humid Climate” by Koffi Djaman, Daran Rudnick, Valere C. Mel, Denis Mutiibwa, Lamine Diop, Mamadou Sall, Isa Kabenge, Ansoumana Bodian, Hossein Tabari, and Suat Irmak." Journal of Irrigation and Drainage Engineering 144, no. 7: 07018027.

Original article
Published: 29 June 2018 in Modeling Earth Systems and Environment
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The objectives of this study were to assess the accuracy of FAO Penman Monteith equation (FAO PM) under limited data conditions and to perform sensitivity analysis to determine approximately the change in reference evapotranspiration (ETref) expected for a known change in one of the independent variables and derive the sensitivity coefficient. Meteorological data were collected from 8 weather stations under humid and semiarid condition in Côte d’Ivoire. The results showed good performance of FAO PM equation under missing solar radiation (Rs) in semiarid condition and under missing wind speed data (U2) and relative humidity (RH) in all locations with coefficient of determination (R2) ranging from 0.70 to 0.99 and regression slope from 0.99 to 1.05. Under missing Rs, RMSE varied from 0.45 to 0.48 mm/day and AME from 0.30 to 0.35 mm/day. The RMSE and AME vary respectively from 0.12 to 0.51 mm/day and from 0.09 to 0.30 mm/day under missing RH data, and respectively from 0.11 to 0.60 mm/day and 0.04 to 0.34 mm/day under missing wind speed data. The poor performance of FAO PM method to estimate ETo was observed when three climatic variables were missing with regression slope from 0.93 to 1.06 and R2 from − 0.06 to 0.26. The response of ETo to changes in all climate variables was linear, with high R2 values (≥ 0.99) in most cases. Any error in Rs, maximum temperature (Tmax) data would have contributed to significant change in ETo estimate. The effect of Rs on change in ETo estimates had the greatest slope (≥ 2.80) in Bouake, Daloa, Korhogo, Man, Seguela whereas it had the lowest slope in Ferkessedougou (slope = 2.74), Odienne (slope = 2.73), Yamoussoukro (slope = 2.77). The effect of Tmax in change in ETo was also important in all location except Daloa and Man with low regression slope values of 1.63, 1.74, respectively. All sensitivity coefficients showed a large degree of daily and seasonal fluctuations and revealed significant differences in northern and central study locations. The sensitivity coefficients of U2 and Tmax were greatest under semiarid condition while the one of Rs were very high in humid condition. Accurate measuring of U2, Tmax and Rs in estimating reference evapotranspiration using Penman–Monteith equation is required.

ACS Style

Komlan Koudahe; Koffi Djaman; Johnson K. Adewumi. Evaluation of the Penman–Monteith reference evapotranspiration under limited data and its sensitivity to key climatic variables under humid and semiarid conditions. Modeling Earth Systems and Environment 2018, 4, 1239 -1257.

AMA Style

Komlan Koudahe, Koffi Djaman, Johnson K. Adewumi. Evaluation of the Penman–Monteith reference evapotranspiration under limited data and its sensitivity to key climatic variables under humid and semiarid conditions. Modeling Earth Systems and Environment. 2018; 4 (3):1239-1257.

Chicago/Turabian Style

Komlan Koudahe; Koffi Djaman; Johnson K. Adewumi. 2018. "Evaluation of the Penman–Monteith reference evapotranspiration under limited data and its sensitivity to key climatic variables under humid and semiarid conditions." Modeling Earth Systems and Environment 4, no. 3: 1239-1257.

Journal article
Published: 16 June 2018 in Agronomy
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A long-term field experiment was conducted from 2002 to 2014 for the evaluation of yield and water productivity of three winter wheat varieties—Kharkof, Scout 66, and TAM107—under sprinkler irrigation at New Mexico State University Agricultural Science Center at Farmington, NM. Winter wheat daily evapotranspiration was estimated following the United Nations Food and Agriculture Organization FAO crop coefficient approach (ETc = Kc ETo), and crop water use efficiency (CWUE), evapotranspiration water use efficiency (ETWUE), and irrigation water use efficiency (IWUE) were estimated for each growing season. There was inter-annual variation in seasonal precipitation and irrigation amounts. Seasonal irrigation amounts varied from 511 to 787 mm and the total water supply varied from 590 to 894 mm with precipitation representing a range of 7.7–24.2%. Winter wheat daily actual evapotranspiration (ETc) varied from 0.1 to 14.5 mm/day, averaging 2.7 mm/day during the winter wheat growing seasons, and the seasonal evapotranspiration varied from 625 to 890 mm. Grain yield was dependent on winter wheat variety, decreased with years, and varied from 1843.1 to 7085.7 kg/ha. TAM107 obtained the highest grain yield. Winter wheat CWUE, IWUE, and ETWUE were also varietal dependent and varied from 0.22 to 1.01 kg/m3, from 0.26 to 1.17 kg/m3, and from 0.29 to 0.92 kg/m3, respectively. CWUE linearly decreased with seasonal water, and IWUE linearly decreased with seasonal irrigation amount, while CWUE, IWUE, and ETWUE were positively correlated with the grain yield for the three winter wheat varieties, with R2 ≥ 0.85 for CWUE, R2 ≥ 0.69 for IWUE, and R2 ≥ 0.89 for ETWUE. The results of this study can serve as guidelines for winter wheat production in the semiarid Four Corners regions. Additional research need to be conducted for optimizing winter wheat irrigation management relative to planting date and fertilization management to reduce the yield gap between winter wheat actual yield and the national average yield.

ACS Style

Koffi Djaman; Michael O’Neill; Curtis Owen; Daniel Smeal; Margaret West; Dallen Begay; Samuel Allen; Komlan Koudahe; Suat Irmak; Kevin Lombard. Long-Term Winter Wheat (Triticum aestivum L.) Seasonal Irrigation Amount, Evapotranspiration, Yield, and Water Productivity under Semiarid Climate. Agronomy 2018, 8, 96 .

AMA Style

Koffi Djaman, Michael O’Neill, Curtis Owen, Daniel Smeal, Margaret West, Dallen Begay, Samuel Allen, Komlan Koudahe, Suat Irmak, Kevin Lombard. Long-Term Winter Wheat (Triticum aestivum L.) Seasonal Irrigation Amount, Evapotranspiration, Yield, and Water Productivity under Semiarid Climate. Agronomy. 2018; 8 (6):96.

Chicago/Turabian Style

Koffi Djaman; Michael O’Neill; Curtis Owen; Daniel Smeal; Margaret West; Dallen Begay; Samuel Allen; Komlan Koudahe; Suat Irmak; Kevin Lombard. 2018. "Long-Term Winter Wheat (Triticum aestivum L.) Seasonal Irrigation Amount, Evapotranspiration, Yield, and Water Productivity under Semiarid Climate." Agronomy 8, no. 6: 96.