Deformation of Sugarcane Leaves and Crop Nutrition

Older leaves tend to show phosphorusdeficiency symptoms before new or younger leaves. They are thinner, narrower and shorter than normal and may be more erect or upright. Leaf blades are dark green to blue-green and margins and tips may show purple or reddish colors. Older leaves may turn yellow, dying back from the tip and margins. Crops are poorly rooted, poorly tillered and young shoots may die back before emerging. Stalks are thin with reduced internodal lengths.

Unlike other micronutrient deficiencies, the symptoms of a molybdenum deficiency occur first in older leaves. They take the form of short, longitudinal chlorotic streaks on the top (apical) one third of the leaf. These older leaves dry prematurely starting from the middle and then towards the tip of the leaf. Stalks become short and slender and growth is slow. Molybdenum deficiency can lead to high yield losses and crop failure.

If in doubt whether it is a nutrition deficiency or disease, please assess through leaf analysis.