Effect of soil type and sowing depth on the germination and early growth of two grain amaranth cultivars.

Grain amaranth is a highly nutritious pseudo‐cereal with good adaptability to a range of environmental conditions and potential to be further cultivated in many areas of the world. Although the crop has good adaptability, soil type can influence crop establishment and production; thus, the objective of this study was to evaluate how cultivar, sowing depth, and soil type affect emergence and early growth of grain amaranth. A pot experiment was carried out in two runs under greenhouse conditions. The experiment was set in a randomized complete block design in a 3 × 5 × 2 factorial arrangement with three soil types (loam, clay loam, and clay) × five sowing depths (0, 5, 10, 15, and 20 mm) × two grain amaranth cultivars (Amaranthus cruentus BRS Alegria and Amaranthus caudatus Inca). Amaranthus caudatus had greater seedling height, stem diameter, number of leaves, root length, fresh weight, and dry weight compared to A. cruentus. Emergence was affected by cultivar and was 15% greater for A. cruentus. Seedling height was significantly greater at a 5 and 20 mm sowing depth. Root growth varied as a function of the interaction between soil types and sowing depths in which the longest roots were obtained when grain amaranth was sown in a loam soil at 10 mm depth. For better growth of grain amaranth, the recommended combination is A. caudatus in a loam soil at a depth between 5 and 20 mm. Core Ideas: Emergence and early growth of amaranth are affected by soil type, sowing depth, and cultivar.Root growth is favored by loam and clay soils, whereas the clay loam soil hinders growth.Grain amaranth should be sown between 5 and 20 mm deep.A. caudatus Inca had the greatest plant height, stem diameter, root length, and fresh and dry weight. [ABSTRACT FROM AUTHOR]