Enhanced germination of primed mericarps of parsley (Petroselinum crispum Mill. Nyman ex A.W. Hill) limited by Alternaria alternata proliferation.

摘要

Osmotic priming (-1.5 or -1.0 MPa for 7, 14 or 21 d at 20 degrees C) increased germination rates of 'Italian Dark Green' and 'Moss Curled' mericarps of parsley, but increasing the duration of priming caused a linear decrease in germination percentage. Fungal colonisation, predominantly by Alternaria alternata, was associated with decreased germination percentage and reduced hypocotyl and radicle lengths. The extent of pericarp damage and fungal colonisation during priming were rated visually from scanning electron micrographs. Pericarp degradation increased from "slight" with some cuticular damage after 7 d priming, to "moderate" with some mesocarp visible, after 21 d priming. Distribution of spores and hyphae of A. alternata increased from "covering less than 1% of the surface" on non-primed mericarps, to "light and uniform" after 7 or 21 d priming. A combination pre-priming (30 min) and post-priming (5 min) mericarp soak in 0.6% (v/v) sodium hypochlorite containing 0.015% (w/v) Tween-20 surfactant controlled fungal proliferation during 7 d priming, but not 21 d priming..