Corn seedling root growth response to soil physical quality

Autor(es)

Nunes, Marcio R. ^[1] ; de Lima, Renato P. ^[2] ; Tormena, Cassio A. ^[3] ; Karlen, Douglas L. ^[4]

Afiliação do(s) autor(es)

^[1] USDA ARS, Natl Lab Agr & Environm NLAE, Univ Blvd, Ames, IA 50011 - USA

^[2] Univ Fed Rural Pernambuco, Dept Agr Engn, Rua Dom Manoel Medeiros S-N, BR-52171900 Recife, PE - Brazil

^[3] Univ Estadual Maringa, Dept Agron, Av Colombo 5790, BR-87020900 Maringa, Parana - Brazil

^[4] DL Karlen Consulting LLC, USDA ARS, NLAE, 487 Ashland Ave, St Paul, MN 55102 - USA

• Tipo de documento: Artigo Científico
• Fonte: AGRONOMY JOURNAL; v. 113, n. 4 JUL 2021.
• Citações Web of Science: 0

Resumo

Plant available water content or matric potential, particle size (texture), aeration, and penetration resistance are soil physical properties that influence soil structure, bulk density, aggregation, and several metabolic plant processes. Collectively they influence productivity and sustainability of agricultural practices, primarily through their impact on root development and growth. To simplify use of these parameters for assessing soil physical condition, the least limiting water range (LLWR) was developed as an integrated, comprehensive soil physical quality indicator. Our objective was to use the LLWR to evaluate corn (Zea mays L.) seedling root growth in soils with clay, sandy clay loam, or sand texture. Overall, root growth was affected by soil water content, aeration, and penetration resistance. Upper and lower LLWR boundaries were defined by a minimum air-filled porosity and maximum soil penetration resistance for water contents between field capacity and permanent wilting point. Herein, the LLWR was calculated using a range of minimum air-filled porosity (0.117-0.146 m(3) m(-3)), field capacity (-2.2 to -5.3 kPa), and permanent wilting point or matric potential values (-461 to -6,516 kPa), and a restrictive penetration resistance value of 1.6 MPa as boundaries. The LLWR was sensitive to soil texture, decreasing from fine to coarse soils. The highest and lowest relative root growth measurements fell inside and outside the LLWR boundaries, proving that this index can successfully predict the optimum soil physical conditions for seedlings root growth and can therefore be used as a sensitive soil physical quality. (AU)

• Processo FAPESP: 15/12934-3 - Fatores da degradação estrutural de solos argilosos sob "plantio direto"
• Beneficiário: Márcio Renato Nunes
• Modalidade de apoio: Bolsas no Brasil - Doutorado