Mango sudden decline: An emerging threat in nursery and mango orchards of Andhra Pradesh

Abstract

Mango sudden Decline (MSD) was observed with clear signs for the first time in the mango orchard and nurseries in the state of Andhra Pradesh. Symptoms were misdiagnosed to dieback and were different in peculiar with gum exudations, splitting of bark, beetle entry holes, vascular discolouration, wilting and rapid death. Morphological and microscopic characterization revealed the presence of Ceratocystis fimbriata and Lasiodiplodia theobromae from the infected bark and twigs. The isolates showed strong pathogenicity on mango cultivar, totapuri fulfilling Koch's postulates. In addition, an association of pathogenic fungi with mango sudden decline and the bark beetle, Hypocryphalus mangiferae was supported with the evidence of signs and their movement in mango seedlings at nurseries. Furthermore this is the first report of MSD caused by Ceratocystis fimbriata and Lasiodiplodia theobromae complex proved to be an emerging threat to mango production in the nursery for grafts production in India.