Germination potential of sweet cherry seeds from commercial cultivars in Chile and implications for PNRSV dissemination risk

Chile is one of the main exporters of cherries to China, with 207 504 t fresh fruit exported in the last four seasons.To determine if seeds of fresh sweet cherries (Prunus avium (L.) L.) intended for human consumption could be a dissemination route for Prunus necrotic ringspot virus (PNRSV), authorities from both countries agreed to evaluate the associated phytosanitary risk.An experimental study was conducted using the six most widely exported commercial cultivars to assess seed germination potential under conditions simulating a postconsumption scenario.The experimental design aimed to reproduce the sequence of conditions that seeds may experience in China, including export storage, and subsequent exposure after fruit consumption or disposal of whole or partially consumed fruit.These conditions were simulated using one control and six treatments, combining cold-chain storage at 0 °C with winter and spring temperature regimes representative of major Chinese cherry-importing provinces (Shanxi, Shanghai, and Shandong).No germination was observed under these conditions in any cultivar.In contrast, in the control treatment, where pits were stratified at 4 °C for 3 mo prior to transfer to greenhouse conditions, germination ranged from 1.7% to 20.3%.This result is primarily attributed to the lack of sufficient cold stratification required to overcome seed dormancy.Thus, our results suggest that the likelihood of Chilean cherries acting as a source of PNRSV dissemination via seeds under the evaluated conditions is very low.