Reducing Psyllid Populations During Key Periods Pays Dividends

Abstract

Asian citrus psyllid (ACP) are at the mercy of their host (citrus) for survival. They need flush to lay eggs and for the nymphs to develop. Prior to HLB, the majority of flushing had been fairly predictable and occurred in the early spring and late summer. The occurrence of flush in young trees is less predictable during the summer rainy season. Although HLB infection has affected the predictability of major flushes, the winter cold period in January and February remains a time when most mature trees have little or no significant new growth. This is a time when ACP reproduction is most restricted and when populations naturally decline. Application of a broad-spectrum insecticide during the winter months has become a well-known technique for managing psyllids. Previous research has demonstrated that if ACP populations are effectively reduced during the dormant winter period, it is easier to keep them down with subsequent sprays later in the season.