Status of citrus decline in Sikkim.
A survey of diseases and disorders affecting mandarin oranges in Sikkim, India, was carried out in 1989 and 1990. Dieback (Colletotrichum gloeosporioides [Glomerella cingulata] and Fusarium sp.) was very severe, followed by sooty mould (Capnodium citri), scab (Elsinoë fawcettii), powdery mildew (Acrosporium tingitanium), felt (Septobasidium pseudopedicellatum) and canker (Xanthomonas campestris pv. citri). Disease intensity varied with location and plant age. Decline was more severe in old orchards than in young ones.