Measures to Control Sheath Rot in Paddy Crop

                                    

Sheath rot is a critical concern in rice cultivation, impacting the health and yield of paddy crops. In this blog, we will examine the causes, symptoms,favorable factors and management strategies for sheath rot, providing essential information to help you effectively combat this damaging disease

What is Sheath Rot in Paddy crop

Sheath Rot is a fungal disease complex that affects rice crops, causing significant yield losses. It can be caused by various fungal pathogens, with the most common being Sarocladium oryzae, Fusarium spp., and Pseudomonas spp.. The disease attacks the leaf sheaths that enclose the developing panicles, leading to rotting and ultimately affecting grain formation and quality. Studies report Sheath Rot causing yield losses anywhere between 20% and 85% in India. Tamil Nadu and Andhra Pradesh have reported losses as high as 80-85%.

Overview of Sheath Rot in paddy crop

Favourable factors for Sheath Rot in Paddy:

• High humidity and warm temperatures (20-28°C)
• Dense crop growth
• Excessive use of nitrogen fertilizers
• Presence of wounds on leaves

Symptoms of Sheath Rot in Paddy:

• Discoloration of the flag leaf sheath: Appearance of irregular greyish-brown or reddish-brown spots on the uppermost leaf sheath (flag leaf sheath) enclosing the young panicles. These spots gradually enlarge and develop grey centers with brown margins, sometimes covering the entire sheath.
• Lesions: The discolored areas progress into water-soaked lesions, eventually rotting the sheath.
• Rotting of the sheath: As the disease progresses, the affected sheath starts to rot, often accompanied by a white, powdery fungal growth (mycelium) visible on the inner surface.
• Panicle problems: Infected panicles may fail to emerge from the sheath or emerge partially. They may also become discolored, stunted, and sterile, with shriveled or unfilled grains.

Measures to control Sheath Rot in Paddy:

Preventive method:

• Bacterization with Pseudomonas fluorescens reduced sheath rot severity by 20-42%, enhanced crop growth, and increased grain yield.
• Foliar spray at 0.2% concentration Bacillus subtilis commencing from 45 days after transplanting at 10 days interval for 3 times depending upon the intensity of disease

Chemical Control of Sheath Rot in Paddy:

For the control of sheath rot , spray the following fungicides at the time of panicle emergence

FAQs related to Sheath Rot in Paddy crop

Q. What is the cause of Sheath rot in rice?

A. Sheath rot is caused by the bacteria sarocladium oryzae

Q. How do you control Sheath rot in rice?

A. Spraying of suitable fungicides like copper oxychloride(katayayni COC50), Carbendazim 12 % + Mancozeb 63 % WP(Katyayani Samartha and Thiophanate Methyl 70% WP(Katyayani KTM) can control Sheath Rot in Paddy.

Q. What is sheath rot in paddy?

A. Sheath rot is a fungal disease affecting rice plants, characterized by rotting and discoloration of the sheaths.

Q. What are the symptoms of Sheath rot in paddy?

A. Discoloration in the flag leaf sheath, where rotting occurs, often affects the sheath enclosing young panicles. The disease appears as irregular spots or lesions with dark reddish-brown margins and gray centers, significantly impacting plant health and yield.