Normalized Difference Vegetation Index as a tool for wheat yield estimation: a case study from Faisalabad, Pakistan

Area of Science:

• Agricultural Science
• Agronomy
• Remote Sensing

Background:

• Normalized Difference Vegetation Index (NDVI) is a valuable tool for assessing crop health and yield.
• Understanding the relationship between NDVI, nitrogen fertilization, and wheat cultivar performance is crucial for optimizing agricultural practices.

Purpose of the Study:

• To evaluate the effectiveness of NDVI as a screening tool for estimating wheat grain yield.
• To investigate the impact of varying nitrogen fertilization levels and different wheat cultivars on NDVI.
• To determine optimal growth stages for NDVI-based yield prediction.

Main Methods:

• Field experiments were conducted over two years using a split-plot design.
• Ten wheat cultivars were subjected to four nitrogen fertilization rates (0, 55, 110, 220 kg ha⁻¹).
• NDVI values were recorded using a Green Seeker handheld sensor at key growth stages.

Main Results:

• The highest NDVI value (0.85) at the grain-filling stage was observed with the highest nitrogen treatment (220 kg ha⁻¹) and the Faisalabad-2008 cultivar.
• Strong positive correlations were found between NDVI and grain yield at the booting (R² = 0.90), grain-filling (R² = 0.90), and maturity (R² = 0.95) stages.
• NDVI effectively differentiated the performance of wheat cultivars under varying nitrogen levels.

Conclusions:

• NDVI is a reliable indicator for estimating wheat grain yield and assessing the impact of nitrogen fertilization and cultivar differences.
• The booting, grain-filling, and maturity stages are optimal for NDVI-based wheat yield prediction in the agroclimatic conditions of Faisalabad.
• The findings are applicable to similar wheat-growing regions, aiding in crop management and yield forecasting.