Virtual Tour Understanding the Plant Analysis Report for Cotton Leaf and petiole analyses provide a way to monitor the nutritional status of cotton. If detected early, nutrient shortages can be corrected before yield and quality are adversely affected. The Plant Advisory Section uses a sufficiency range approach for primary interpretation of leaf results. As indicated in the figure on the bottom left, the index scale is divided into zones of sufficiency. Within this range, yield or growth has been maximized.
Petioles are the best indicator of nitrogen status.
Petiole nitrate nitrogen is correlated with yield, especially early in the season. The figure on the bottom right indicates the expected decline in petiole nitrate nitrogen as a normal plant fruits. The adequate range decreases as the season progresses. This graph can be used to estimate nitrogen sufficiency and the need for additional nitrogen during the growing season. Leaf and petiole analyses are most reliable when moisture and other stress-related factors are not influencing growth.