02146naa a2200205 a 450000100080000000500110000800800410001910000150006024501110007526000090018652015160019565000230171165000300173465000200176465000200178465000220180465000150182670000230184177300760186411329452022-12-16 2022 bl uuuu u00u1 u #d1 aARAUJO, L. aNeonectria ditissima spore release in apple plants and detached branches in Brazil.h[electronic resource] c2022 aProlonged periods of leaf wetness, high temperatures, and relative humidity during spring/summer are ideal conditions for the development of apple diseases in Brazil. In 2012, European canker, caused by Neonectria ditissima was officially confirmed in Brazilian apple orchards. The disease has a high potential to adversely affect fruit production as all symptomatic branches and/or all apple trees need to be eliminated to contain the epidemic in the orchards. Knowledge of N. ditissima spore release is required to optimize management practices because it facilitates the prediction of European canker infection risks and improves disease management decisions. Thus, the objective of this study was to investigate the release of N. ditissima spores from apple plants and detached branches over time. In the São Joaquim region of Brazil, both conidia and ascospores of N. ditissima can be released from cankers alive and/or dead in apple tissues year-round. In Brazil, peaks of spore release from N. ditissima were observed in traps when there was rainfall, irrespective of the season. Ascospore peaks were more frequent and higher than those of conidia trapped in both traps and apple tissues. Detached branches of symptomatic apple trees actively released spores of N. ditissima in the three years of evaluation, but in smaller numbers in comparison to traps with live plants. Thus, new and rigorous management measures should be adopted to control European canker dissemination in Brazilian apple orchards. aA2 quarantine pest aCylindrocarpon heteronema aEuropean canker aMalus domestica aNectria galligena aPerithecia1 aPINTO, F. A. M. F. tJournal of Plant Pathology, New Yorkgv. 104, n. 1, p. 1283-1289, 2022.