Temporal Analysis of Candidatus Liberibacter asiaticus in Citrandarin Genotypes Indicates Unstable Infection

Background: Huanglongbing (HLB) is currently one of the most devasting diseases in citrus plants worldwide. Resistance against its causal agent, Candidatus Liberibacter asiaticus (CLas), commercial Citrus species remains a challenge, even though they show differences CLas multiplication. Methods: A total 14 citrandarins and their parents (Sunki mandarin Poncirus trifoliata cv. Rubidoux) were top-grafted onto canopy potted ‘Valencia’ sweet orange with high titers. The grafted genotypes tested for infection physiological effects disease (starch accumulation callose deposition) 12 months. Results: All infected by during time frame experiment. However, decrease rate ranging from 50% to 80% hybrids H109, H126, H157, H222 was observed 360 days top-grafting. undetected real-time PCR H106 at end experiment, which had low levels starch deposition. Conclusions: all citrandarins, but over detected some specific genotypes, led less