Studyoninduceddiseaseresistanceoftwonovelderivates:apyrazolopyrimidinederivativeBDO-1andapyridazinonederivativePDZ-1

A pyrazolopyrimidine derivative ((E)-N-(2-fluoro-4-(trifluoromethyl)styryl)-1-methyl-1H-pyrazolo 3,4-dpyrimidin-4-amine, BDO-1) and a pyridazinone derivative (methyl 4-hydroxy-1-(4-methoxyphenyl)-6-oxo-1,6-dihydropyridazine-3-carboxylate, PDZ-1), were first synthesised by researchers from East China University of Science and Technology. In this study, the potential inducing systemic aquired resistance and the field application techniques for these two derivatives were investigated. The results showed that BDO-1 and PDZ-1 exhibited no fungicidal effect against Fusarium oxysporum and Corynespora cassiicola. Pot experiments in the greenhouse revealed that those two compounds have the potential to induce systemic aquired resistance to seven vegetable diseases. BDO-1 demonstrated good control efficacies at the concentration of 10 mg/L against cucumber bacterial angular leaf spot, cucumber corynespora leaf spot, cucumber wilt, cucumber downy mildew, tomato early blight, tomato gray leaf spot and pepper phytophthora blight, with the efficacies of 58.81%, 61.79%, 69.88%, 64.14%, 54.42%, 54.85% and 63.59%, respectively. At the same concentration, PDZ-1 also exbibited good control efficacies against cucumber bacterial angular leaf spot and corynespora leaf spot, which were 62.33% and 59.15%, respectively. Field efficacies of BDO-1 and PDZ-1 on cucumber wilt were 62.95 % and 48.45%, respectively. Finally, this research also demonstratde that the best control efficacies against cucumber fusarium wilt and cucumber corynespora leaf spot can be achieved for both BDO-1 and PDZ-1 under the same conditions (optimum inducing concentration of 10 mg/L, inducing for 5 times at interval of 5 days).