Corn Yield Response to Reduced Water Use at Different Growth Stages

Hirut Kebede,Krishna N Reddy,Ruixiu Sui,Daniel K Fisher,Nacer Bellaloui,William T Molin

doi:10.4236/as.2014.513139

Abstract

To develop an efficient water use strategy for crop irrigation, we need to know how much water can be reduced without decreasing yield. A study was designed to determine corn growth stages at which water could be reduced without affecting grain yield, and at what soil moisture level water deficit stress begins in the plants in a silt loam soil. An experiment was conducted in a randomized complete block with a 3 × 4 factorial design in four replications, where treatments consisted of three soil moisture levels [100%, 75%, and 50% of field capacity (FC) of a silt loam soil by weight] and four growth stages [fourteen leaf stage (V14), silking (R1), milk (R3), and dent (R5) stages] in a greenhouse. Growth stages at the reproductive and grain fill stages of corn were selected because this study was intended for the Mississippi Delta, where there is frequent drought during these growth stages making irrigation necessary for corn production, whereas there is usually adequate rainfall during the vegetative growth stages. Results from this study showed that reducing soil moisture from 100% FC (fully irrigated) to 75% FC of a silt loam soil starting at the R1 growth stage in corn did not reduce yield significantly compared to yield from the 100% FC, while saving a significant amount of water. Physiological investigations at the three soil moisture treatments showed that a mild moisture deficit stress might have started at the 75% FC treatment. With further investigation, if savings in water at 75% FC result in a significant reduction in energy cost, it may be profitable to reduce soil moisture to 75% FC in a silt loam soil.

Highlights

Efficient use of water in agriculture has become an issue as available water resources become scarce [1] [2].How to cite this paper: Kebede, H., Sui, R.X., Fisher, D.K., Reddy, K.N., Bellaloui, N. and Molin, W.T. (2014) Corn Yield Response to Reduced Water Use at Different Growth Stages
No significant differences in yield were observed between the 100% and the 75% field capacity (FC) treatments at the R1, R3 (Milk) and R5 stages, but at the 50% FC treatment yield was significantly lower than the 100% FC in all growth stages (Figure 1)
At the R1, R3 and R5 growth stages the reduction in yield in the 75% FC treatment ranged only from 5% to 9%, whereas it was 17% to 23% in the 50% FC treatment compared with the 100%

Summary

Introduction

Efficient use of water in agriculture has become an issue as available water resources become scarce [1] [2].How to cite this paper: Kebede, H., Sui, R.X., Fisher, D.K., Reddy, K.N., Bellaloui, N. and Molin, W.T. (2014) Corn Yield Response to Reduced Water Use at Different Growth Stages. In order to develop an efficient water use strategy in crop irrigation, we need to know how much water can be reduced without decreasing yield. This depends, among other things, on the growth stage of the plant, its rate of water use and plant available water (which depends on the soil type) involving evapotranspiration demand. In the Mississippi Delta, there is usually adequate precipitation during the vegetative growth stages of corn plants (April-May), but during the reproductive and the grain fill stages (June-August) there is frequent drought and irrigation is required to avoid yield loss. The need for efficient use of irrigation water in corn in the Mississippi Delta arises mainly during the reproductive and the grain fill stages of corn

Methods

Results

Discussion

Conclusion