Morphological and architectural development of root systems in sorghum and maize

• Published in: Plant and soil 2010-08, Vol.333 (1-2), p.287-299
• Main Authors: Singh, Vijaya, van Oosterom, Erik J, Jordan, David R, Messina, Carlos D, Cooper, Mark, Hammer, Graeme L
• Format: Article
• Language: English
• Subjects: Agricultural soils; Agronomy; Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Architectural control; Architecture; Biological and medical sciences; Biomedical and Life Sciences; Corn; Developmental biology; Ecology; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Genotype & phenotype; Germination; Grasses; Hybridity; Hybrids; Leaves; Life Sciences; Moisture content; Nodal root; Plant Physiology; Plant roots; Plant Sciences; Plants; Regular Article; Root angle; Root architecture; Root systems; Roots; Scutellum; Seminal root; Seminal roots; Soil moisture; Soil Science & Conservation; Soil water; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Sorghum
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-010-0343-0

Root systems determine the capacity of a plant to access soil water and their architecture can influence adaptation to water-limited conditions. It may be possible to associate that architecture with root attributes of young plants as a basis for rapid phenotypic screening. This requires improved understanding of root system development. This study aimed to characterise the morphological and architectural development of sorghum and maize root systems by (i) clarifying the initiation and origin of roots at germination, and (ii) monitoring and quantifying the development of root systems in young plants. Three experiments were conducted with two maize and four sorghum hybrids. Sorghum produced a sole seminal (primary) root and coleoptile nodal roots emerged at the 4th–5th leaf stage, whereas maize produced 3–7 seminal (primary and scutellum) roots and coleoptile nodal roots emerged at the 2nd leaf stage. Genotypic variation in the flush angle and mean diameter of nodal roots was observed and could be considered a suitable target for large scale screening for root architecture in breeding populations. Because of the relatively late appearance of nodal roots in sorghum, such screening would require a small chamber system to grow plants until at least 6 leaves had fully expanded.