diseased bean leaf

africa agricultural agriculture agriculturer agronomy algeria bacteria bean blight branch burn chlorophyll chlorose chlorosis country countryside curling destruction disease diseased downy etiolation feed field fongicide food fungi gall green late leaf leaves legume line mediterranean mildew natural nature necrose necrosis north pathogen pathogens pattern pesticide phytopathology plant powdery rust showing symptom tissue tuberculoi vegetables wilt wilting yellowing