Reduction and Synergistic Effect of Seven Adjuvants on the Control of Rice False Smut by Tebuconazole

LI Xinyi; WANG Zuoqian; GUO Chenchen; XU Ting; CHANG Xiangqian; CAI Xuan; YANG Xiaolin; ZHANG Shu; LÜ Liang; DENG Qingchao

doi:10.15933/j.cnki.1004-3268.2026.02.010

Abstract：To investigate the synergistic enhancement effect of different adjuvants on the control of rice false smut by tebuconazole,seven novel adjuvants were selected including Nanosilica(NMG),Mairun(MR),Keousen(KOS),Maifei(MF),Benniu(BN),Jijian(JJ),and Chaoniu(CN).Firstly,the improvement in spreading performance of reduced tebuconazole by the addition of adjuvants was quantitatively analyzed using the contact angle measurement method.Subsequently,greenhouse pot experiments with artificial inoculation and fungicide spraying,as well as field trials under natural conditions,were conducted.A comprehensive evaluation of the synergistic control effect of reduced tebuconazole with adjuvants was performed.The results showed that after 50%reduction of tebuconazole combined with each adjuvant,the contact angle of the solution on rice leaves significantly decreased,and the spreading performance was markedly improved.Under conditions of artificial inoculation with rice false smut,adding the seven adjuvants to 50%reduced tebuconazole increased the disease inhibition by 18.0%to 71.3%compared with the single 50%reduced tebuconazole treatment.Among them,the CN combination treatment exhibited the best inhibition effect,with a inhibition rate of 85.5%.Field control results indicated that 30%reduced tebuconazole combined with CN achieved the highest control efficacy against rice false smut,reaching 87.1%,which showed a significant increase of 48.6%compared with the 30%reduced tebuconazole alone and was comparable to the standard tebuconazole dose alone(86.6%).In addition,the control efficacy of 30%reduced tebuconazole combined with MF,JJ,MR,or BN showed no significant difference compared with the standard tebuconazole dose alone.These results indicate that the addition of novel adjuvants can achieve enhanced control efficacy with reduced fungicide dosage against rice false smut,and the nanoscale CN adjuvant shows particularly pronounced synergistic effects,providing a basis for environmentally friendly disease management in rice.