TITLE:
Water Deficit Stress Effects on Corn (Zea mays, L.) Root:Shoot Ratio
AUTHORS:
J. G. Benjamin, D. C. Nielsen, M. F. Vigil, M. M. Mikha, F. Calderon
KEYWORDS:
Shoot Ratio, Least Limiting Water Range, Water Stress, Corn Root Development, Soil Environment
JOURNAL NAME:
Open Journal of Soil Science,
Vol.4 No.4,
April
22,
2014
ABSTRACT: A study was conducted at
Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water
deficit stress on corn (Zea mays, L.)
root and shoot biomass. Corn plants were grown under a range of soil bulk
density and water conditions caused by previous tillage, crop rotation, and irrigation
management. Water deficit stress (Dstress) was quantified by the
number of days when the water content in the surface 0.3 m deviated from the
water content range determined by the Least Limiting Water Range (LLWR). Root
and shoot samples were collected at the V6, V12, and R1 growth stages. There
was no significant correlation between Dstress and shoot or root
biomass at the V6 growth stage. At the V12 and R1 growth stages, there were
negative, linear correlations among Dstress and both root biomass
and shoot biomass. The proportional decrease of shoot biomass was greater than
the proportional decrease in root biomass, leading to an increase in the
root:shoot ratio as water deficit stress increased at all growth stages.
Determining restrictive soil conditions using the LLWR may be useful for
evaluating improvement or degradation of the soil physical environment caused
by soil management.