Know more

On young carrot seedbeds, there is a fear of carrot-willow aphid  (Cavariella aegopodii) which induces the cotyledon seedling leaves to fade which can lead to destruction of the early seedlings. Attacks are possible from sprouting and the high risks are from April to June. Moreover, this aphid transmits Carrot mottle dwarf virus (CMotDV) in association with carrot red leaf virus (CtRLV). On foliage, another aphid is also found (Semiaphis dauci) which causes leaves to become taut. Finally in spring, the hawthorn aphid (Dysaphis crataegi) migrates onto roots of growing carrots and causes them to shatter. Aphicide treatments are generally unnecessary unless colonization occurs in young crops at sprouting between April and June.

On celery, aphids can transmit several viruses. The two most important are the cucumber mosaic (CMV) and the celery mosaic virus (CeMV). CMV is often associated with the Alfalfa (lucerne) mosaic virus  (AMV). The principal vectors of CMV and AMV are the cotton aphid (Aphis gossypii), the cowpea aphid (Aphis craccivora), the green peach aphid (Myzus persicae) and the rusty banded aphid (Dysaphis apiifolia). The main vector of CeMV is the honeysuckle aphid (Hyadaphis foeniculi). Predominance of one or the other of these viruses depends on the frequency of celery crops in the rotation: occasional crops will mainly be hit by CMV whereas frequent return of celery cultivation and the presence of wild Apiaceae, umbelliferan viral reservoirs, will favour CeMV.