Morphological Characteristics of Maize Canopy Development as Affected by Increased Plant Density

Area of Science:

• Agronomy
• Plant Physiology
• Crop Science

Background:

• Optimizing crop productivity with increased plant density necessitates understanding organ development under competition.
• Interplant competition significantly influences plant morphology and growth dynamics.

Purpose of the Study:

• To investigate how maize organ development (lamina, sheath, internode) is affected by varying plant densities and associated interplant competition.
• To identify key morphological indicators of interplant competition in maize.

Main Methods:

• Field experiment with four maize plant densities: 2, 6, 12, and 20 plants m⁻².
• Detailed analysis of organ lengths, widths, and internode diameters across different plant densities.
• Assessment of organ extension sensitivity to varying levels of interplant competition.

Main Results:

• Increased plant density led to longer laminae and sheaths in lower phytomers but shorter ones in upper phytomers.
• Lamina and internode extension responded to mild competition but not severe competition.
• Lamina width and internode diameter decreased with higher plant densities due to reduced growth rates.
• Sheath extension was less sensitive to competition than lamina extension.

Conclusions:

• Organ expansion rate is a critical morphological factor for quantifying interplant competition in maize.
• Understanding these developmental responses is crucial for optimizing planting densities for improved crop yields.