02377naa a2200349 a 450000100080000000500110000800800410001902200140006002400550007410000260012924500960015526000090025152014230026065000180168365000220170165000090172365000100173265000120174265000160175465000100177065000170178065000140179765300150181165300160182665300210184270000190186370000200188270000200190270000250192270000220194777300580196921480552022-11-04       2021    bl uuuu     u00u1 u    #d  a1983-40637 ahttps://doi.org/10.1590/1983-40632021v51669162DOI1 aCARVALHO, J. C. B. de  aEfficiency of a new Waitea circinata extract against rice pathogens.h[electronic resource]  c2021  aWaitea circinata (Warcup & Talbot) is an orchid antagonist mycorrhizal fungus with biocontrol potential against rice pathogens. This study aimed to optimize the extraction method, obtain a new extract and evaluate its efficiency against rice pathogens in vitro and in vivo, as well as to compare it with other extraction methods and W. circinata. The extracts were obtained and screened for in vitro growth inhibition against the pathogens Cochliobolus miyabeanus, Monographella albescens and Sarocladium oryzae, using the following extracts: mycelial, crude, lyophilized and mycelial mass. An additional in vitro assay was performed with the principal rice pathogen (Magnaporthe oryzae), in order to evaluate the conidial germination and appressorium formation. Based on this evaluation, the lyophilized and mycelial mass extracts were tested in vivo against rice blast (M. oryzae) and compared to the W. circinata mycelial suspension, in different application forms (simultaneous and previous). The mycelial mass extract inhibited all the pathogens, and the crude and lyophilized extracts inhibited C. miyabeanus and M. albescens, respectively. The mycelial mass extract inhibited the M. oryzae conidial germination and appressorium formation by 80 %, and the simultaneous and previous applications suppressed the rice blast by 94 %. These results indicate that the new extract can be used to control rice pathogens.  aBlast disease  aFungal brown spot  aRice  aArroz  aBrusone  aEscaldadura  aFungo  aMancha Parda  aPodridão  aBiocontrol  aBiocontrole  aWaitea circinata1 aCHAIBUB, A. A.1 aSOUSA, K. C. I.1 aBRITO, D. C. de1 aFILIPPI, M. C. C. de1 aARAÚJO, L. G. de  tPesquisa Agropecuária Tropicalgv. 51, e66916, 2021.