Life cycle of aphids Aphids inflict serious damage to a variety of crops. They are notorious virus vectors and have an enormous reproductive capacity. There are lots of different coloured species and they occur in all kinds of crops. The nymphs and adults extract food materials from the plant and disturb the balance of the plant’s growth hormones. It can result in deformed leaves or even the death of young plants. Aphids secrete honeydew which is a nutrient source for sooty moulds. Their saliva