Rice Research: Open Access
Open Access

Rhizoctonia, progression

Introduction

Aggregate sheath spot and stem rot have many similarities in their disease cycles. Sclerotia produced by Rhizoctonia oryzae-sativae are resistant to unfavourable conditions and allow the fungus to overwinter. These overwintering bodies float on the field water surface in the spring and early summer, causing initial infections at the water line. In contrast to the sclerotia of a septum near each hyphal branch and a slight constriction at the branch are diagnostic. R. solani is subdivided into anastomosis groups based on hyphal fusion between compatible strains [1].Aggregate sheath spot of rice can also colonize the culm, where it may cause a culm rot, but this aspect of the disease is rare in California. Limiting carryover inoculum from one year to the next by removing or destroying crop residues is the most effective strategy to manage aggregate sheath spot. If monitoring reveals that leaf lesions are approaching the flag leaf sheath, treatments may be required. Controlling the environment, crop rotation, and the use of resistant varieties, It can decrease yield up to 50%, and reduce its quality [2]. Are all things that can be done. When it comes to treating aggregate sheath spot, monitoring is crucial. Examine tillers weekly after tillering for the presence and progression of aggregate sheath spot lesions at several sites across the field. A therapy may be justified if lesions have begun to extend and are reaching the flag leaf sheath or the leaf sheath below the flag leaf. Treat lesions before they become a problem. Complete control of Rhizoctonia species is not possible, but the severity of the pathogen can be limited. Successful control depends on characteristics of the pathogen, host crops, and the environment [3].

For effective and cost-effective control of sheath blight and associated yield losses, an integrated management approach combining resistant or moderately resistant cultivars, sound cultural practises, and foliar fungicide application is desirable. Varietal vulnerability, field disease history, early disease scouting, and local meteorological circumstances that favour the disease are all factors to consider.

References

1. Wiese MV (1987) Compendium of wheat diseases. American Phytopathological Society. pp. 124 pp.
2. Fleet N (1983) Rice Sheath Blight: A Major Rice Disease. Plant Disease. 67 (7): 829.
3. Uchida K, Janice Y (2011) Rhizoctonia Solani Knowledge Master. Janice Uchilda Knowledge Master.