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), in commercial Citrus species remains a challenge, even though they show differences in CLas multiplication. Metho...

Full description

Bibliographic Details
Authors: Cavichioli, Thais Magni, Curtolo, Maiara, Cristofani-Yaly, Mariangela, Rodrigues, Josiane, Della Coletta-Filho, Helvecio [UNESP]
Format: article
Status:Published version
Publication Date:2022
Country:Brasil
Institution:Universidade Estadual Paulista (UNESP)
Repository:Repositório Institucional da UNESP
Language:English
OAI Identifier:oai:repositorio.unesp.br:11449/245111
Online Access:http://dx.doi.org/10.3390/agronomy12102566
http://hdl.handle.net/11449/245111
Access Level:Open access
Keyword:Huanglongbing
citrus rootstock
disease tolerance
bacteria
Description
Summary:Background: Huanglongbing (HLB) is currently one of the most devasting diseases in citrus plants worldwide. Resistance against its causal agent, Candidatus Liberibacter asiaticus (CLas), in commercial Citrus species remains a challenge, even though they show differences in CLas multiplication. Methods: A total of 14 citrandarins and their parents (Sunki mandarin and Poncirus trifoliata cv. Rubidoux) were top-grafted onto the canopy of potted 'Valencia' sweet orange plants with high CLas titers. The grafted genotypes were tested for CLas infection and physiological effects of the disease (starch accumulation and callose deposition) for 12 months. Results: All tested genotypes were infected by CLas during the time frame of the experiment. However, a decrease in the infection rate ranging from 50% to 80% for the hybrids H109, H126, H157, and H222 was observed 360 days from the top-grafting. CLas was undetected by real-time PCR in H106 at the end of the experiment, which had low levels of starch and callose deposition. Conclusions: CLas infected all of the tested citrandarins, but a decrease in the infection rate over time was detected for some specific genotypes, which led to less starch accumulation and callose deposition.