Estimates of genetic parameters for brown rot resistance in Prunus persica

S. Scariotto, M. Dini, M.C.B. Raseira, J. Santos
Brown rot can cause dramatic economic impacts on the commercial production of several Prunus species, including peach, nectarine, plum, apricot, cherry and almond, in most producer countries. In Brazil, this disease is caused by Monilinia fructicola. The objective of this work was to estimate the genetic parameters for brown rot resistance in 144 accessions from the germplasm bank of Embrapa Clima Temperado. Fruits of each accession were harvested at the firm ripe stage. Prior to inoculation, twnety fruits per genotype were disinfected by immersion in a 70% v/v alcohol solution, followed by a three minute immersion in a 0.5% v/v NaClO solution, and rinsing in distilled water. The inoculation was made by deposition of a 10 μL drop with 2.5×104 spores mL‑1 of M. fructicola, on the fruit surface that was wounded with a microsyringe. Inoculated fruits were incubated at 25±1°C and 75% relative humidity for 72 h. The samples were evaluated for disease severity (average diameter of lesions and sporulation). Broad sense heritability estimates for lesion and sporulation diameter was 50 and 13%, respectively. The coefficient of variance was 46% for sporulation diameter and 20% for lesion diameter. The studied population exhibited genetic variability and therefore potential for breeding. 'Bolinha', 'Marfim', 'Jade', 'Dourado II' and selections SB9, Cascata 1281, Cascata 967, SB25, Conserva 1904, Conserva 1844 and Cascata 657 showed higher resistance than the other accessions.
Scariotto, S., Dini, M., Raseira, M.C.B. and Santos, J. (2021). Estimates of genetic parameters for brown rot resistance in Prunus persica. Acta Hortic. 1304, 289-298
DOI: 10.17660/ActaHortic.2021.1304.40
Monilinia fructicola, heritability, mixed models, genetic resistance, genetic variability

Acta Horticulturae