Grain amaranths are a group of pseudo-cereal species known for drought and heat stress tolerance, high nutritional quality and potential as forage and feed for animals or as a milled or popped seed for baking and industrial processes for human food. Like most row crops, the grain amaranths have a high requirement for soil nitrogen (N) and other types of fertility to grow to their full potential. The goal of this study was to test three levels of urea fertilization (0, 115 and 230 kg/ha N) and four grain amaranth genotypes, two from species A. cruentus and the USDA and two from species A. hypochondriacus and SSE, for yield components, including seed weight, proportion seed per panicle, plant height, panicle length, panicle width and panicle weight. The genotype USDA107 was observed to grow taller and had longer but thinner panicles compared to USDA127 as well as SSE42 and SSE30 with each of these genotypes being shorter but with wider panicles. These contrasts were stable across fertilization levels. An increase in the yield potential of seed weight and proportion seed per panicle was seen at high dose compared to mid-dose or control, unfertilized treatments. Correlations were positive and highly significant for all traits except panicle length and proportion seed or panicle length and width which were negatively correlated. We expect these novel results to spur further study of grain amaranths in the southeastern United States.
Anuradha, K.M., Zinta, G., Chauhan, R., Kumar, A., Singh, S., et al . (2023) Genetic Resources and Breeding Approaches for Improvement of Amaranth ( Amaranthus spp .) and Quinoa ( Chenopodium quinoa ). Frontiers in Nutrition , 10, Article 1129723. https://doi.org/10.3389/fnut.2023.1129723
Blair, M.W., Riggins, C. and de la Rosa, A.P.B. (2023) Editorial: Amaranthus: Naturally Stress-Resistant Resources for Improved Agriculture and Human Health, Volume II. Frontiers in Plant Science , 14, Article 1329377. https://doi.org/10.3389/fpls.2023.1329377
Riggins, C.W., Barba de la Rosa, A.P., Blair, M.W. and Espitia-Rangel, E. (2021) Editorial: Amaranthus: Naturally Stress-Resistant Resources for Improved Agriculture and Human Health. Frontiers in Plant Science , 12, Article 726875. https://doi.org/10.3389/fpls.2021.726875
Joshi, D.C., Sood, S., Hosahatti, R., Kant, L., Pattanayak, A., Kumar, A., et al . (2018) From Zero to Hero: The Past, Present and Future of Grain Amaranth Breeding. Theoretical and Applied Genetics , 131, 1807-1823. https://doi.org/10.1007/s00122-018-3138-y
Stetter, M.G., Joshi, D.C. and Singh, A. (2025) Assessing and Mining Grain Amaranth Diversity for Sustainable Cropping Systems. Theoretical and Applied Genetics , 138, Article No. 171. https://doi.org/10.1007/s00122-025-04940-w
Thapa, R. and Blair, M.W. (2019) Morphological Assessment of Cultivated and Wild Amaranth Species Diversity. Agronomy , 8, Article 272. https://doi.org/10.3390/agronomy8110272
Thapa, R., Edwards, M. and Blair, M.W. (2021) Relationship of Cultivated Grain Amaranth Species and Wild Relative Accessions. Genes , 12, Article 1849. https://doi.org/10.3390/genes12121849
Dharajiya, D.T., Trivedi, G.T., Thakkar, N.J., Pachchigar, K.P., Teli, B., et al . (2022) Genomics-Assisted Design of Biotic Stress Resistant Vegetable Amaranths. In: Kole, C., Genomic Designing for Biotic Stress Resistant Vegetable Crops , Springer, 261-300. https://doi.org/10.1007/978-3-030-97785-6_7
Tillman, P.B. and Waldroup, P.W. (1987) Effects of Feeding Extruded Grain Amaranth to Laying Hens. Poultry Science , 66, 1697-1701. https://doi.org/10.3382/ps.0661697
Tillman, P.B. and Waldroup, P.W. (1986) Processing Grain Amaranth for Use in Broiler Diets. Poultry Science , 65, 1960-1964. https://doi.org/10.3382/ps.0651960
Blair, M.W., Londoño, J.M., Buitrago-Bitar, M.A., Wu, X. and Brenner, D.M. (2023) Differentiation of Andean and Mesoamerican Accessions in a Proposed Core Collection of Grain Amaranths. Frontiers in Plant Science , 14, Article 1144681. https://doi.org/10.3389/fpls.2023.1144681
Blair, M.W., Thapa, R., Wu, X., Edwards, M., Yahaya, D., Hickok, D., et al . (2023) Use of Genomics and Phenomics in Grain Amaranths for Diversity Assessment and Breeding in the Americas. In: Neglected and Underutilized Crops , Elsevier, 95-114. https://doi.org/10.1016/b978-0-323-90537-4.00010-7
Wu, X. and Blair, M.W. (2017) Genotyping by Sequencing (GBS) Polymorphism Diversity in Grain Amaranths and Relatives. Frontiers in Plant Science , 8, Article 1960.
Kaur, N., Kaur, S., Agarwal, A., Sabharwal, M. and Tripathi, A.D. (2024) Amaranthus Crop for Food Security and Sustainable Food Systems. Planta , 260, Article No. 59. https://doi.org/10.1007/s00425-024-04490-3
Mukuwapasi, B., Mavengahama, S. and Gerrano, A.S. (2024) Grain Amaranth: A Versatile Untapped Climate-Smart Crop for Enhancing Food and Nutritional Security. Discover Agriculture , 2, Article No. 44. https://doi.org/10.1007/s44279-024-00057-8
Joshi, D.C., Chaudhari, G.V., Sood, S., Kant, L., Pattanayak, A., Zhang, K., et al . (2019) Revisiting the Versatile Buckwheat: Reinvigorating Genetic Gains through Integrated Breeding and Genomics Approach. Planta , 250, 783-801. https://doi.org/10.1007/s00425-018-03080-4
Hui, D., Yu, C.L., Deng, Q., Saini, P., Collins, K. and de Koff, J. (2018) Weak Effects of Biochar and Nitrogen Fertilization on Switchgrass Photosynthesis, Biomass, and Soil Respiration. Agriculture , 8, Article 143. https://doi.org/10.3390/agriculture8090143
Endres, C. (1986) Influence of Production Practices on Yield and Morphology of Amaranth cruentus and Amaranth hypochondriacus . Master’s Thesis, University of Arkansas.
Elbehri, A., Putnam, D.H. and Schmitt, M. (1993) Nitrogen Fertilizer and Cultivar Effects on Yield and Nitrogen‐Use Efficiency of Grain Amaranth. Agronomy Journal , 85, 120-128. https://doi.org/10.2134/agronj1993.00021962008500010023x
Kalinowski, L.S., Navarro, J.P., Concha, A.I.R., Hermoza, G.C., Pacheco, R.A., Choquevilca, Y.C., et al . (1992) Grain Amaranth Research in Peru. Food Reviews International , 8, 87-124. https://doi.org/10.1080/87559129209540931
Bressani, R., Gonzalez, J.M., Elias, L.G. and Melgar, M. (1987) Effect of Fertilizer Application on the Yield, Protein and Fat Content, and Protein Quality of Raw and Cooked Grain of Three Amaranth Species. Qualitas Plantarum Plant Foods for Human Nutrition , 37, 59-67. https://doi.org/10.1007/bf01092301
Adhikari, P., Joshi, L.P., Ayer, D.K. and Tiwari, K.R. (2022) Agromorphological Diversity and Disease Assessment of Grain Amaranth in Lamjung, Nepal. Advances in Agriculture , 2022, 1-12. https://doi.org/10.1155/2022/8969390
Akanbi, W.B., Akande, M.O., Baiyewu, R.A. and Akinfasoye, J.O. (2000) The Effect of Maize Stover Compost and Nitrogen Fertilizer on Growth, Yield and N Uptake of Amaranth. Journal of Agricultural Research , 1, 6-15.
Ochieng, J., Schreinemachers, P., Ogada, M., Dinssa, F.F., Barnos, W. and Mndiga, H. (2019) Adoption of Improved Amaranth Varieties and Good Agricultural Practices in East Africa. Land Use Policy , 83, 187-194. https://doi.org/10.1016/j.landusepol.2019.02.002
Olufolaji, A.O. (1989) Response of Four Amaranthus Cultivars to N Levels and Harvesting Methods. Test Agrochemicals Cultivars , 10, 166-167.
Ainika, J.N., Amans, E.B., Olonitola, C.O., Okutu, P.C. and Dodo, E.Y. (2012) Effect of Organic and Inorganic Fertilizer on Growth and Yield of Amaranthus caudatus L. in Northern Guinea Savanna of Nigeria. World Journal of Engineering and Pure & Applied Sciences , 2, Article 26.
Nyankanga, R.O., Onwonga, R.N., Wekesa, F.S., Nakimbugwe, D., Masinde, D. and Mugisha, J. (2011) Effect of Inorganic and Organic Fertilizers on the Performance and Profitability of Grain Amaranth ( Amaranthus caudatus L.) in Western Kenya. Journal of Agricultural Science , 4, 223-231. https://doi.org/10.5539/jas.v4n1p223
Pospišil, A., Pospišil, M., Varga, B. and Svečnjak, Z. (2006) Grain Yield and Protein Concentration of Two Amaranth Species ( Amaranthus spp .) as Influenced by the Nitrogen Fertilization. European Journal of Agronomy , 25, 250-253. https://doi.org/10.1016/j.eja.2006.06.001
Walters, R.D., Coffey, D.L. and Sams, C.E. (1988) Fiber, Nitrate, and Protein Content of Amaranthus Accessions as Affected by Soil Nitrogen Application and Harvest Date. HortScience , 23, 338-341. https://doi.org/10.21273/hortsci.23.2.338
He, H.P. and Corke, H. (2003) Oil and Squalene in Amaranthus Grain and Leaf. Journal of Agricultural and Food Chemistry , 51, 7913-7920. https://doi.org/10.1021/jf030489q
Waldroup, P.W., Hellwig, H.M., Longer, D.E. and Endres, C.S. (1985) The Utilization of Grain Amaranth by Broiler Chickens. Poultry Science , 64, 759-762. https://doi.org/10.3382/ps.0640759
Weber, L.E. (1989) Amaranth Grain Production Guide. Rodale Press.