Sugarcane Thirty-first to thirty-second week practices

• Irrigation should be given in this week.

Scale Insect:

Symptoms:

• The leaves of infested canes show signs of tip drying and unhealthy pale green color and severe infestation causes yellowing.
• Severe desapping leads to non-opening of leaves, which also turn yellow and finally dry up.
• Infested crop losses its vigor, canes shrivel, growth is stunted and the internode length is reduced drastically.
• Ultimately the cane dries up. Such canes when slit open appear brownish red. 
• Thick brown encrustations are seen on the nodal and internodal regions in severely affected canes.

Management:

Cultural method:

• Use resistant varieties like CO 439, CO 443, CO 453, CO 671, CO 691 and CO 692
• Select and plant the scale insect free sets.
• Keep the fields and bunds free from weeds.
• Avoid water stagnation in the field for a longer period.
• Avoid repeated ratoons.

Physical method:

• Detrash the crop at the 150th and 210th day of planting.
• Setts should be dipped in dichlorvos at 1ml per liter of water and placed in cement bags with the mouth tied and transported to the planting area.

Biological method:

• Release Chilocorus nigritus (or) Pharascymnus horni egg card @ 5cc/ac
• Also release hymenopteran parasitoids like anabrotepis mayurai, cheiloneurus sp and predatory mites like saniosulus nudus and tyrophagus puttseartiae which feed on scale insects.

Chemical control:

• Pre-soak the sets in 0.1% solution malathion.
• Spray dimethoate @ 2ml/ lit along with sticker after detrashing.

Apply contact insecticides like dichlorvos or any @ 2ml/lit of water by using a hand sprayer.