Guar root and shoot growth as affected by soil compaction

Doglas  Bassegio; Marcos Vinicius  Mansano Sarto; Ciro Antonio  Rosolem; Jaqueline Rocha  Wobeto Sarto

Guar root and shoot growth as affected by soil compaction

Autores

Doglas Bassegio

Marcos Vinicius Mansano Sarto

Ciro Antonio Rosolem

Jaqueline Rocha Wobeto Sarto

Editor

Universidade Federal de Goiás

Descripción

Guar (Cyamopsis tetragonoloba L.) is commonly grown in arid lands, because of its high drought-tolerance. However, soil compaction may be a limiting factor to its growth. This study aimed to evaluate the guar growth, according to the soil penetration resistance (0.20 MPa, 0.33 MPa, 0.50 MPa,0.93 MPa and 1.77 MPa, in a layer with depth between 0.15 m and 0.20 m), in a Rhodic Acrudox soil. The shoot and root drymass, root length by the Q1/2 index (mechanical soil penetration resistance in which the root growth is reduced by 50 %) and root diameter were evaluated. The impairment of the guar shootgrowth begins when the penetration resistance is greater than around 1 MPa. The soil compaction alters the distribution of guar roots in the soil profile, concentrating them in the 0.15 m layer, but it does not prevent roots from penetrating this layer and developing in depth. The root diameter increases in the compacted layer. A soil penetration resistance of up to 1.77 MPa does not influence the root length density below the compacted layer, as well as the total root length density of guar. Although the guar Q1/2 index is greater than 1.58, the shoot and root dry mass are impaired.