winter rapeseed plants during vegetation with visible nutrient deficiencies - leaf discoloration

agriculture autumn black blackleg blossom botany canola chemistry chlorosis damage deficiencies deficiency discoloration disease diseases during evergreen farm feeding fertilization fertilizer field flower food fruit garden green herb herbicide infect infection leaf leaves macro macronutrients microelements micronutrients natural nature nutrient nutrition oil phosphorus pink plant plants produce purple rape rapeseed red season shortage shrub soil spots spraying tree vegetable vegetation visible wildflower winter woodland yellow zinc