Corn root morphological attributes as influenced by soil management in a coarse-textured soil

Abstract

This study was done to investigate corn (Zea mays L.) root response to tillage and manure applications on a sandy loam soil in western Iran. Three tillage systems (no-till [NT], chisel plow [CP], and moldboard plow [MP]) and three rates (0, 30 and 60 Mg [dry weight] ha⁻¹) of cattle manure were evaluated. Root samples were collected when 100% of tassels appeared. Root length density (RLD), root weight (RW), root radius (RR) and root surface area (RSA) were determined. Tillage and manure significantly affected RLD only in the upper layers. RLD was highest for MP and lowest for NT. Increased topsoil strength decreased root growth with NT. RLD and RSA were higher with CP than NT in the 0 – 20 cm layer, but below 20 cm these values were with CP due to compaction. Higher manure rates significantly increased root morphological characteristics. RLD values for NT, CP and MP were 2.79, 2.96, and 3.47 km m⁻³, respectively. RW and RR rankings were NT > MP > CP. Highest RLD and RSA were measured within MP plus 60 Mg ha⁻¹ manure. Overall, short-term effects of conservation tillage on corn root development were not significant, because applying manure decreased adverse effects of high soil strength under no-till.

Keywords:

• Root length density
• root radius
• root surface area
• manure
• tillage