Field evaluation of lucerne cultivars for resistance to blue–green lucerne aphid and pea aphid (Acyrthosiphon spp.) in New Zealand

Abstract Population density and aphid feeding damage scores of Acyrthosiphon kondoi Shinji(blue–green lucerne aphid) were significantly lower, and dry matter yield of forage was higher, in lucerne cv. Rere than in cv. Wairau or cv. Saranac grown in field trials. ‘Rere ‘is apparently resistant to colonisation and utilisation of the plant by A. kondoi, and is tolerant of aphid feeding damage. Populations of cv. Saranac and ‘CUF 101‘selected for resistance to A. kondoi were also resistant to this species and tolerant of feeding damage.Population density of Acyrthosiphon pisum Harris (pea aphid) was probably too low to be damaging and no consistent cultivar effects on numbers were found.