SURVEY OF MANGO PESTS IN REUNION ISLAND, WITH A FOCUS ON PESTS AFFECTING FLOWERING

Abstract

The development of Integrated Pest Management on mango requires the knowledge of the main pests, their biological cycle and their relationships with mango. The objective of this study was to survey pests in mango orchards on Reunion Island and to rank them according to the severity of damage produced. As flowering is a key stage for mango production, a particular focus was made on pests affecting this stage of growth. Five orchards situated in three locations of the mango production area were monitored over a two-year period with visual assessment and the use of insect traps. The two main cultivars planted in Reunion Island are the Floridian cultivar 'Cogshall' and the local cultivar 'Jose'. The main phenological stages of the trees were recorded: vegetative growth, flowering and fruit maturity. Overall, thirteen pests were observed in mango orchards and six of them were of economic importance: three species of fruit flies, two gall midges and one bug. The blossom mango gall midge (Procontarinia mangiferae Felt) and the green bug (Orthops palus Taylor) primarily affect the flowering stage. The blossom mango gall midge is a mango-specific pest, of which larvae grow within the axis of inflorescence, whereas the green bug is a polyphagous non-specific pest, of which larvae and adults feed on inflorescences. Each of these species can destroy the inflorescences within a few days. Young bursting inflorescences are damaged more by the blossom mango gall midge, whereas mature flowering inflorescences are damaged by the green bug. This is the first report of damage on mango caused by this Miridae. The long duration of flowering in mango orchards contributes to maintaining high levels of these pest populations and is consequently a main drawback to control their populations and damage. Technical practices aimed at synchronizing flowering could be useful in controlling these pests without the use of pesticides. (Resume d'auteur)