Work

Plant Hormesis Induced by Ultraviolet Light-c for Inducing Resistance of Brown Rot of Peaches

Year: 1992

Type: article

Abstract: Low hormetic doses of ultraviolet light (UV-C) stress on exposed peaches ( Prunus persica ). reduced brown rot resulting from field and artificial inoculation from Monilinia fructicola . To test the hypothesis that UV-C induced resistance through host responses the following tests involving biochemical changes (phenlyalanine ammonia-lyase activity (PAL) and ethylene production (EP)), bioassay of antifungal activity of tissue extracts to the fungus, and latent infection of rot free peaches previously treated with and without UV-C were determined. Exposure of peaches to UV-C dose of 7.5×10 4 ergs/mm 2 promoted an increase in PAL and EP compared to the control. As the PAL activity increased, percent storage rots decreased. Antifungal activity to the fungal conidia in UV-C treated peach extract showed that the percent conidia germination was reduced 3 folds. Preharvest infection of brown rot which indicated latent infection was significantly reduced. To test for the germicidal effect of UV-C on M. fructicola on the surface of peaches, an artificial epiphytic population of the fungus was deposited on the peaches. A negative relationship between UV-C dose of 1.3 to 40×10 4 ergs /mm 2 , colony forming units and number of decaying brown rot lesions were found.

Source: HortScience

DOI: 10.21273/hortsci.27.11.1168h