For the proper use of fertilizers in the paddy field, Punjab University of Agriculture is explaining how to use the “Leaf Color Chart” to know the requirement of nitrogen fertilizers.
• Apply basal dose of 25 kg urea per acre
• Start matching color of the first fully exposed leaf from the top with the LCC at 7 days interval after 14 days of transplanting.
• Whenever the greenness of 6 or more out of 10 leaves is lighter than LCC shade 4 apply 25 kg per acre.
• No urea should be applied if color of leaves is equal to or darker than LCC shade 4.
• Use of LCC should be discontinued after initiation of flowering and no more urea should be applied.