Impact of Huanglongbing (HLB) on grapefruit pectin yield and quality during grapefruit maturation

Huanglongbing (HLB) is a plant disease responsible for citrus tree decline, increased fruit drop, and deteriorated quality. Citrus pectin billion-dollar industry which may be impacted by the HLB epidemic. We compared physio-chemical properties of in peel from affected grapefruit collected open-air trees against healthy grown under protective screens (CUPS) at two developmental stages to ascertain impacts on pectin. qPCR detected causal agent HLB, determined if tested was or non-healthy, color °Brix defined fruit's maturity. Depending maturity there between 16%–25% decrease yield. showed significantly (p < 0.05) arabinose, galactose, immature galacturonic acid sugars, resulting lower Homogalacturan/Rhamogalacturan I ratio degree branching (DBr) had 7% outside methylation (DMoutside) 28% decreased blockiness (DB). The DB, absolute (DBabs), methylesterification (DM), DMoutside indicates larger number non-endopolygalacturonase digestible GalA blocks suggesting exhibit more random pattern. Grapefruit maturation resulted 20% increase yield with 30% molecular weight. Understanding HLB's impact will provide customers manufacturers insight into how these factors industry.