Rooting depth and density of corn and sorghum grown under rainfed conditions
1984
Thanom Klodpeng | Charoon Sukasame | Chaiyawoot Nimmalungkul (Chiang Mai Unive., (Thailand). Faculty of Agriculture)
During early growth, root penentration by corn was faster than sorghum. However, at 45 DAE root penetration had exceeded by 100 cm for both crops. For each crop, root number and root density in the top-soil (0-10 cm) were at a maximum 45 DAE. Both parameters decreased rapidly with depth, the decrease being more marked in corn than sorghum; this decrease was attributed to an increase in soil bulk density. Although root number in sorghum exceeded that for corn at depth, for the whole profile total root number for corn was greater than for sorghum. In corn, and exponential sigmoid relationship described the relationship between root number and rooting density with depth, regardless of growth stage. In sorghum, this type of relationship was observed only during early growth; in later growth a simple sigmoid association better described the relationship. As moisture status throughout the soil profile was adequate for both crops, the root growth patterns defined reflected differences between the crops in association with the particular soil properties
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