Evaluation of fluopyram against single and concomitant inoculation of Rhizoctonia solani and Meloidogyne graminicola infesting rice crop

The fungicidal and nematicidal properties of fluopyram were assessed against Rhizoctonia solani (sheath blight) and Meloidogyne graminicola (rice root-knot) pathogens of rice in single and concomitantly inoculated pots during two consecutive cropping seasons (2017 and 2018) on a susceptible rice cultivar Pusa Sugandha-5. Standard fungicides, azoxystrobin and nematicide, carbofuran were used to compare the efficiency of fluopyram. The plants grown in the soil singly inoculated with 2 g R. solani (2 × 10 6 CFU/g) and 1000 J 2s of M. graminicola suffered a suppression of 13–30% in the plant growth and 20–29% in grain yield. However, simultaneous inoculation of both the pathogens did not reveal any significant change in the disease severity but marginally affect the plant growth and yield when compared to their individual effects. Soil treatment with fluopyram reduced the adverse effect of the nematode and fungus in simultaneously inoculated plants but significantly varied with fungus and nematode alone inoculation. Soil application (SA) with fluopyram proved most efficacious against root-knot nematode and reduced the disease severity by 67–74% and reproduction factor by 66–70%, resulted in a 17–32% plant growth promotion and yield enhancement. Fluopyram also significantly reduced the sheath blight fungus and suppressed the disease severity by 47–53% and soil population by 68%, resulted in a 9–31% plant growth promotion and yield enhancement. The study demonstrated that there was no interaction between R. solani and M. graminicola . Application of fluopyram effectively controls sheath blight and rice root-knot disease in rice and offers to be an alternative chemical for effective management of R. solani and M. graminicola in the areas/fields where sympatric infestations occur.