Red Rot Disease: Strategies For Controlling This Enemy Of Sugarcanes

By Spy Uganda

Are you struggling with the persistent and destructive red rot disease in your sugarcane fields? Red rot is a fungal disease caused by Colletotrichum falcatum, which is one of the most devastating diseases that can affect sugarcane plants. This disease can significantly reduce your quality and yield of sugarcane crops, leading to substantial economic losses for farmers. It is important to be able to identify the symptoms of red rot in order to take appropriate action. This article will provide you with essential information like symptoms and management methods to help you control and manage red rot in sugarcane crops.

 Type of Infestation 

• Primary infection occurs through infected setts, while the secondary spread within the field can happen through various means such as irrigation water and cultivation tools. Additionally, rain splash, air currents and dew drop also play a role in spreading conidia from diseased plants to healthy ones.
• The conidia which settle on the leaves may germinate and invade the leaves through different types of wounds. Stem infection can occur through insect bores and root primordia. The soil-borne fungus can enter healthy setts through different types of wounds.

Red Rot of Sugarcane Symptoms

Here are some signs to promptly identify an infection of red rot in your sugarcane fields:

• The affected canes show a change in leaf color, from green to orange and eventually turning yellow in the third or fourth leaf.
• Affected leaves begin to dry out from bottom and progress towards the top.
• In cases where fungal spores penetrate the leaf sheath through the leaf midrib, reddish spots may also become visible on the underside of the leaf midrib.
• The external symptoms become visible only after 16-21 days after infection and it takes an additional 10 days for the entire cane to dry out.
• Upon splitting open the affected cane, the inner region displays a reddish color with intermittent white patches along the length of the cane.
• Sometimes, the pith inside the cane is filled with blackish brown liquid and emits an alcoholic odour.

Red Rot of Sugarcane Control Measures

Are you witnessing any of the symptoms mentioned above in your sugarcane field? If so, it’s time to act swiftly. Don’t delay! Implementing an integrated disease management strategy is crucial for controlling the spread of sugarcane red rot disease and minimizing crop damage. In the following sections, we will explore effective measures to combat and manage sugarcane red rot infection.

Cultural Measures

• Choose setts that are free from disease for planting.
• Grow resistant sugarcane varieties such as Co 86032, Co 86249, CoSi 95071, CoG 93076, CoC 22, CoSi 6 and CoG 5.
• Adopt crop rotation in red rot affected fields with rice for one season and other crops for two seasons.
• Provide proper drainage to avoid stagnation.
• Avoid ratoon crop in affected sugarcane.
• Harvest the diseased crop as early as possible.
• Dip the cut ends or entire setts in fungicide solution like one percent Bordeaux mixture.

Physical Measures

• Treat the sugarcane setts with aerated steam at 52°C for 4 to 5 hours and by moist hot air at 54°C for 2 hours.

Mechanical Measures

• Collect and destroy affected leaves and canes by burning.

Biological Measures

• Spot Bio Fungicide contains an effective microbial culture Pseudomonas fluorescence which can effectively control red rot of sugarcane. For an acre, apply 2 kg of spot bio fungicide to get better results.

Red Rot of Sugarcane Chemical Control

• Amistar Top Fungicide is an effective broad-spectrum and long-term control fungicide which controls a wide range of diseases including sugarcane red rot. Its technical content is Azoxystrobin 18.2% + Difenoconazole 11.4% SC. The recommended dosage is 1 ml per litre of water.
• Before planting, soak the setts in a solution of 0.1% Carbendazim or 0.05% Triadimefon for 15 minutes.
• Tebusul fungicide is an efficient and cost-effective solution for controlling fungal diseases. It is an effective fungicide with protective, creative and eradicative action. Its technical content is Tebuconazole 10% + Sulphur 65% WG. The recommended dosage is 2.5 gm per litre of water.