The pale green hoppers/jassids are the suking pest, which lay eggs on leaves, adults and nymphs both suck the sap from the leaves, stems. While infesting they secrete toxic sticky saliva called honeydew that may cause sooty mold to develop. The leaves turn yellow, gets twisted and plants become stunted. The affected leaves curl upward, start to wilt. Leaf hoppers are common pests in most of the vegetables, effectively control the hoppers/jassids in vegetables.