Phenotypic quantification of root spatial distribution along circumferential direction for field paddy-wheat

Area of Science:

• Agricultural Science
• Plant Biology
• Soil Science

Background:

• Plant roots are crucial for water/nutrient uptake, anchorage, and soil interaction.
• Understanding root traits can enhance crop stability and yield in challenging environments.
• Existing quantitative indicators for root system architecture (RSA) are limited, often lacking spatial circumferential analysis.

Purpose of the Study:

• To propose and validate five new quantitative indicators for RSA dynamics.
• To analyze root growth and distribution along circumferential orientations.
• To assess the impact of fertilization rates on root spatial heterogeneity.

Main Methods:

• Developed five novel indicators to quantify RSA along eight circumferential orientations.
• Employed visualization technology including in-situ field root sampling, digitization, and reconstruction.
• Conducted field experiments on paddy-wheat cultivation with varying fertilization rates.

Main Results:

• Root growth for paddy-wheat was confined to a cylinder (180 mm diameter, 200 mm height) at the seedling stage.
• The five new indicators showed slow, fluctuating trends that decreased over time within the soil volume.
• Fertilization treatments (N70 and N130) exhibited similar impacts on root spatial heterogeneity.

Conclusions:

• The five new indicators effectively quantify the spatial dynamics of paddy-wheat root systems at the seedling stage.
• These metrics are significant for comprehensive crop root quantification in breeding programs.
• The study contributes methodological innovation to field crop root research.