Prochloraz is no longer suitable for bakanae disease control, say Chinese provinces like Zhejiang and Jiangsu

By Think Real - In 2017 and 2018, a period of 2 years, researchers of China’s Zhejiang A&F University took samples from rice fields in Shaoxing, Jiaxing, and Jinhua cities of Zhejiang Province to test the resistance to prochloraz, and meanwhile, to check the cross resistance to other commonly used DMIs (sterol demethylation inhibitors) fungicides. This was intended to make it clear about the resistance of fusarium fujikuroi, the main pathogenic bacterium of bakanae disease, to prochloraz.

The results show that the pesticide-resistant bacterial strains appearing in the said 2 years accounted for 53.2% and 46.7% of the total samples, respectively. Such high frequencies mean that, the fusarium fujikuroi in Zhejiang Province has developed strong resistance to prochloraz, and that, a rotation system using fungicides of different mechanisms of action should be established for disease control.

Additionally, Jiangsu Province has also clearly put forward that the soaking of seeds using prochloraz should be stopped, in view of the fact that the fusarium fujikuroi in most areas of the province has showed huge resistance to prochloraz. Heilongjiang, Liaoning, and Sichuan provinces have also strongly recommended the replacement of prochloraz with phenamacril.