Varietal susceptibility (Rosy leaf curling aphid)

• Some apple varieties are resistant to rosy leaf curling aphid, notably Cox.
• Others, such as Bramley, are susceptible and some, notably Golden Delicious and Worcester Pearmain are highly susceptible.
• The single gene responsible for resistance has been identified and is now used in apple breeding programmes.
• At East Malling Research, where the resistance gene was first identified, all recently released new varieties have included the resistance gene.