PREDICTIVE MODEL FOR ASCOSPORE RELEASE OF GUIGNARDIA CITRICARPA USING CLIMATOLOGICAL DATA

Delia M. Dummel, Juan P. Agostini, Ricardo Moschini
Citrus black spot, caused by Guignardia citricarpa, is a cosmetic disease that affects fruit appearance for export. A predictive model for ascospore release was developed using weather data. Ascospore release was monitored in a ‘Valencia’ sweet orange grove in Misiones, Argentina, on a weekly basis using a Burkard spore trap while climatological data were obtained from a Davis GroWeather station during the 2008/09 season. The daily variables considered in the model were maximum and minimum temperatures (°C), rainfall (mm), and days with more than 10 hours of leaf wetness (DMojt). Cumulative data were calculated for the 7 days prior to the weekly ascospore count for 28 weeks and categorized as high, medium or low. Using stepwise regression, two models were defined for ascospore release. The first model had only one variable (LogitPrS = – 4,553 + 1,6015 * DMojt) with a correlation coefficient of 67.9%, whereas the second model including as an additional variable the number of days with temperatures between 20 and 29°C (DT) (LogitPrS = –6,1318 + 1,8108 * DMojt + 3,4829 * DT) had a correlation coefficient of 82.1%.
Delia M. Dummel, , Juan P. Agostini, and Ricardo Moschini, (2015). PREDICTIVE MODEL FOR ASCOSPORE RELEASE OF GUIGNARDIA CITRICARPA USING CLIMATOLOGICAL DATA. Acta Hortic. 1065, 953-963
DOI: 10.17660/ActaHortic.2015.1065.119
https://doi.org/10.17660/ActaHortic.2015.1065.119
Phyllosticta citricarpa, Burkard volumetric spore trap, citrus black spot, inoculum dynamics
English

Acta Horticulturae