Low-Level Copper Plus Chitosan Applications Provide Protection Against Late Blight of Potato

Fig. 1. Potato leaflets taken from plants treated with (A) water, (B) a combination of the copper sulfate pentahydrate solution (CT-100) at 14 µg/ml plus crab-shell chitosan at 25 µg/ml, and (C) CT-100-only at 14 µg/ml. After 2 days the leaflets were removed from the plant and inoculated with genotype US 8 of P. infestans (25,000 sporangia/ml within a 25 µl volume per leaflet). The photo was taken 8 days following inoculation and incubation at 16°C, with an 8-h light/16-h dark day cycle.



Image from Plant Health Progress article:
Low-Level Copper Plus Chitosan Applications Provide Protection Against Late Blight of Potato