Fungal Decay of First-Crop and Main-Crop Figs

Abstract

Fig cultivars grown in California typically have two crops, although the first crop may be unimportant commercially. The first crop, also known as the breba crop, ripens in late spring and early summer, whereas the main or second crop ripens in late summer. For both cultivars studied, Conadria and Calimyrna, the first-crop figs typically are left in the orchard unharvested. First-crop figs had relatively high levels of fungal decay and tended to have more fungal decay than main-crop figs, especially Alternaria rot (caused by Alternaria alternata and Ulocladium atrum). At least 16 different Aspergillus spp. were found decaying first-crop figs. Fig smut, a serious disease caused by Aspergillus niger and related fungi, usually was present at approximately the same level in first-crop and main-crop figs. Aspergillus spp. known to produce the mycotoxins aflatoxin or ochratoxin were found decaying first-crop figs. Aflatoxin was detected in first-crop figs at low levels similar to those detected in the main-crop figs. Because the abundant spores produced on the first-crop figs can infect main-crop figs, the fungal decay of first-crop figs might result in higher levels of decay for main-crop figs.