A research method for semi-automated large-scale cultivation of maize to full maturity in an artificial environment

Authors: WEITHORN, MATTHEW - Purdue University; Penn, Chad; CAMBERATO, JAMES - Purdue University

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/15/2021
Publication Date: 9/22/2021
Citation: Weithorn, M., Penn, C.J., Camberato, J. 2021. A research method for semi-automated large-scale cultivation of maize to full maturity in an artificial environment. Agronomy Journal. 11(10):1898. https://doi.org/10.3390/agronomy11101898.
DOI: https://doi.org/10.3390/agronomy11101898

Interpretive Summary: Conducting research on nutrient uptake and timing is very difficult in the field using soils because of the high variability and strong buffering of soils. Alternatives such as hydroponics, greenhouses, and growth chambers have some advantages and disadvantages for conducting nutrient uptake research. We developed an indoor growth technique with 100% artificial conditions and media where nutrient availability can be precisely controlled. This included inert silica media, semi-automated fertigation, changing photoperiod, full spectrum LED lights with high intensity, ventiliation system, temperature and moisture control, and drainage. Ninety-six corn plants were grown to full maturity and demonstrated a strong response to nutrient treatments, illustrating how well the system worked. Plants were nearly identical to field-grown corn in yield and nutrient uptake. The described systems possesses all the benefits without disadvantages of field, greenhouse, hydroponics, and growth chamber experiments. This technique is useful in detailed nutrient uptake and plant growth studies that require a complete control of nutrient availability and ambient growing conditions, such as temperature, humidity, light intensity and photoperiod.

Technical Abstract: Growing maize (Zea mays L.) for research purposes by field, greenhouse, growth chamber, and media-less techniques has unique advantages and disadvantages. The objectives of this study were to develop a practical technique for productively cultivating several maize plants from seed to physiological maturity (R6) in a growth room environment, with precise control of nutrient availability and timing, and evaluate its utility for the purpose of measuring plant responses to variations in nutrient concentrations. Construction and testing of a semi-automated growth room for conducting nutrient studies on 96 maize plants utilizing simulated or artificial conditions was described. Plant growth response to a range of solution phosphorus (P) concentrations were tested to evaluate the utility of the technique. Maize yield components were measured and compared to values for field-grown plants. Due to ideal conditions and successful simulation of light intensity, diurnal fluctuations in temperature and RH, and changing photoperiod, grain yield and tissue nutrient concentrations were comparable to field-grown maize, although with greater shoot bio-mass. Plants responded positively to increased P concentrations in fertigation. The technique can be used for large-scale plant nutrient studies that require precise control of bioavailability and timing as well as manipulation of light intensity and photoperiod duration.