As a number of insects damage canola crop, Agriculture Department has instructed farmers to protect canola crop from various insect pests. Appropriate measures must be taken timely in order to ensure higher production. They said that both nymph and adult stage of aphid intensely attack canola, Toria, Raya and Tara Mera.
Aphids appear in clusters and stick to plant shoots, flowers and leaves. This insect cause significant injury from December to March. They have the ability to rapidly increase in population and usually it takes 7-10 days to mature. These grow very fast during cold and humid climatic conditions. Both the nymph and adult stage suck plant sap from shoots, leaves and flowers. Heavily-infested leaves wilt and turn yellow because of excessive sap removal. As a result unhealthy seed formation occurs.
They secrete a sticky substance (honeydew) that encourages a fungal growth causing branches and leaves to appear black. It has a negative effects on the growth and development of crop and thus leads to yield loss. For the non-chemical control of aphids, weeds should be removed, as these act as a host for the pest. Biological control agents such as lady bird beetle, green lacewing should be encouraged. In case of severe attack farmers should consult agriculture experts in order to use chemicals for its control.