damaged leaves on a red currant leaves strongly affected with gall aphid on currants

affected agriculture aphid aphids bad bedbug bitten bug bush closeup cruciferous cultivation currant damage danger disease disinfection flea fuliginea fungal fungi fungicide gall gallow garden green growth health high humidity infected infection insect leaf leaves management mildew nature nutrition pathogen pest plant powdery red shrub sphaerotheca summer surface symptom worm