Control of Pyricularia oryzae and Helminthosporium sativum through wheat seeds treatment with fungicides

Abstract

The efficiency of several fungicides on the control of Pyricularia oryzae and Helminthosporium sativum in wheat seeds was evaluated. Lab (blotter) and field tests were performed, using seeds of the wheat cultivar "Anahuac" with 11.5% and 19.5% of natural infection with P. oryzae and H. sativum, respectively. All chemical treatments reduced the incidence of both pathogens. P. oryzae was erradicated when the seeds were treated with iprodione, iprodione + thiram, carboxin + thiram, triflumizole + methyl tiophanate, triflumizole, methyl tiofanate, triadimenol + anilazine, anilazine, mancozeb + carbendazin, carbendazin, guazatine + imazalil, iminoctadine, etiltrianol and prochloraz. Transmission of P. oryzae by the wheat seeds was detected in the field. Iprodione + thiram, triflumizole + methyl tiophanate, triflumizole, triadimenol + anilazine, triadimenol, anilazine, guazatine + imazalil, iminoctadine, etiltrianol and prochloraz were the best ones in the control of H. sativum, eliminating this pathogen from the treated seeds. In the field, iminoctadine and etiltrianol, were the best fungicides in controling H. sativum. Iprodione + thiram and carboxin + thiram increased the emergency in the field when compared with the control.