Correlation studies on nitrogen for sunflower crop across the agroclimatic variability

Area of Science:

• Agronomy
• Plant Physiology
• Crop Science

Background:

• Nitrogen fertilizer is a critical factor influencing sunflower (Helianthus annuus L.) yield.
• Understanding the relationship between nitrogen rates, growth parameters, and yield components is essential for optimizing sunflower production.

Purpose of the Study:

• To investigate the correlation between sunflower yield components and growth parameters under varying nitrogen fertilization rates.
• To determine the optimal nitrogen application rate for maximizing sunflower grain yield across different environments.

Main Methods:

• Field experiments were conducted across three sites over two growing seasons (2008-2009).
• Three sunflower hybrids were evaluated under five nitrogen (N) rates (0, 60, 120, 180, 240 kg ha(-1)).
• Key growth parameters including total dry matter (TDM), leaf area index (LAI), leaf area duration (LAD), and crop growth rate (CGR) were measured.

Main Results:

• Total dry matter production and grain yield showed a positive linear association with LAI, LAD, and CGR.
• The highest sunflower yield was achieved with an N application rate of 180 kg ha(-1), exceeding the standard rate of 120 kg ha(-1).
• Nitrogen application rate significantly correlated with sunflower growth and development across diverse climatic conditions.

Conclusions:

• Humid climates appear most suitable for sunflower production, based on yield component associations.
• Growth parameters can effectively predict grain yield under varying climatic conditions.
• Optimizing nitrogen doses based on regional conditions and climate variations is crucial for sustainable sunflower production.