HortScience


Publications
15

Root System Reductions of Grafted ‘Valencia’ Orange Trees Are More Extensive Than Aboveground Reductions after Natural Infection with Candidatus Liberibacter Asiaticus

Citation
Tardivo et al. (2024). HortScience 59 (5)
Names
Ca. Liberibacter asiaticus Liberibacter
Abstract
Huanglongbing (HLB), which is associated with the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas), is a devastating disease that affects citrus trees worldwide. Because of the pervasiveness of the bacteria and psyllid vector, the disease is considered endemic in Florida. Although the effects of CLas on tree growth and physiology have been investigated for decades, most studies compared infected and noninfected trees under greenhouse conditions. This study used newly planted fiel

Response of Citrus Germplasm Seedlings to Candidatus Liberibacter Asiaticus Infection under Controlled Greenhouse Conditions

Citation
Bisi et al. (2024). HortScience 59 (3)
Names
Liberibacter
Abstract
Huanglongbing (HLB) is a major disease of citrus associated with phloem-limited bacteria in the genus Candidatus Liberibacter that affects all known citrus species and relatives, with many commercial cultivars being greatly damaged. Testing cultivar tolerance to HLB in field conditions is difficult because of the erratic spread of the bacteria, scion and rootstock interactions, and influence of many biotic and abiotic factors on the tree response to the disease. This study aimed to validate the

Relative Influence of Rootstock and Scion on Asian Citrus Psyllid Infestation and Candidatus Liberibacter asiaticus Colonization

Citation
Tardivo et al. (2023). HortScience 58 (4)
Names
Ca. Liberibacter asiaticus
Abstract
The citrus industry in Florida faces a destructive endemic disease, known as huanglongbing (HLB), associated with Candidatus Liberibacter asiaticus (CLas), a phloem-limited bacterium, and transmitted by the Asian citrus psyllid (ACP). Rootstocks are regarded as critical to keep citrus production commercially viable and help trees cope with the disease. Although most scions are susceptible, some rootstocks are HLB-tolerant and may influence ACP infestation and CLas colonization and therefore the

Optimization of vqPCR for Reliable Detection of Viable Candidatus Liberibacter asiaticus in Citrus

Citation
Louzada et al. (2022). HortScience 57 (6)
Names
Liberibacter Ca. Liberibacter asiaticus
Abstract
Citrus Huanglongbing (HLB, also known as “citrus greening”), an important disease worldwide, is associated with three species of phloem-limited Candidatus liberibacter, of which Candidatus L. asiaticus (CLas) is the predominant one that has severely affected citrus production. TaqMan real-time polymerase chain reaction (PCR) (TM) has been the standard and very efficient method to diagnose several strains of Candidatus Liberibacter in citrus; however, it detects total bacteria and is unable to di

Different Sweet Orange–Rootstock Combinations Infected by Candidatus Liberibacter asiaticus under Greenhouse Conditions: Effects on the Scion

Citation
Bodaghi et al. (2022). HortScience 57 (1)
Names
Ca. Liberibacter asiaticus
Abstract
The devastating citrus disease huanglongbing (HLB) associated with the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas) has caused a more than 70% reduction in citrus production since its discovery in Florida in 2005. Most citrus scion cultivars are sensitive to HLB, whereas some cultivars used as rootstocks are tolerant. Using such tolerant rootstocks can help trees to cope better with the disease’s impact. Evaluating rootstock effects on a grafted scion in the field takes many

Different Sweet Orange‒Rootstock Combinations Infected by Candidatus Liberibacter asiaticus under Greenhouse Conditions: Effects on the Roots

Citation
Bodaghi et al. (2022). HortScience 57 (1)
Names
Ca. Liberibacter asiaticus
Abstract
Grafting a scion onto a rootstock results in physical and physiological changes in plant growth and development, which can affect tree vigor, productivity, and tolerance to stress and disease. Huanglongbing (HLB) is one of the most destructive citrus diseases and has become endemic in Florida since its introduction in 2005. It is associated with the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas), which cause severe metabolic disruptions in affected plants. Although most scion c

An Improved Method to Track Changes of Candidatus Liberibacter asiaticus Titer in HLB-affected Citrus Trees

Citation
Etxeberria et al. (2019). HortScience 54 (8)
Names
Ca. Liberibacter asiaticus
Abstract
Monitoring the health of Huanglongbing-affected citrus trees by following changes in leaf Candidatus Liberibacter asiaticus (CLas) titer has an inherent element of imprecision because CLas titer varies considerably within the tree canopy and with calendar seasons. In addition, the destructive sampling method used to determine CLas titer entails a different set of leaves per sampling period adding to the inconsistency and inexactitude of the results. To overcome these ambiguities and to reduce th

Ground Application of Overdoses of Manganese Have a Therapeutic Effect on Sweet Orange Trees Infected with Candidatus Liberibacter asiaticus

Citation
Zambon et al. (2019). HortScience 54 (6)
Names
Ca. Liberibacter asiaticus
Abstract
There is accumulating evidence that root system collapse is a primary symptom associated with Huanglongbing (HLB)-induced tree decline, especially for commercial sweet orange and grapefruit trees on Swingle and Carrizo rootstocks. Maintaining root health is imperative to keep trees productive in an HLB-endemic environment. Preliminary greenhouse and field studies have shown that HLB-impacted trees had secondary and micronutrient deficiencies that were much greater in the roots than in the leaves

Influence of Photoperiod Duration and Phloem Disruption through Scoring on Growth, Disease Symptoms, and Bacterial Titer in Citrus Graft Inoculated with Candidatus Liberibacter asiaticus

Citation
Stover et al. (2016). HortScience 51 (10)
Names
Ca. Liberibacter asiaticus
Abstract
Plants inoculated with the huanglongbing (HLB)-associated bacterium, Candidatus Liberibacter asiaticus (CLas) typically must be monitored for 8–10 months to identify differences in susceptibility between genotypes. Continuous light is reported to accelerate development of HLB symptoms and field observations suggest that trees girdled by tags or tree ties showed greater symptoms. Therefore, an experiment was conducted assessing HLB susceptibility as influenced by light/dark periods of 12 hours: 1

Influence of Citrus Source and Test Genotypes on Inoculations with Candidatus Liberibacter asiaticus

Citation
Stover et al. (2016). HortScience 51 (7)
Names
Ca. Liberibacter asiaticus
Abstract
Assessments of the resistance of citrus germplasm to huanglongbing (HLB) can be expedited by inoculating plants under laboratory or greenhouse settings with the HLB bacterium, Candidatus Liberibacter asiaticus (CLas). Consistent rapid screening is critical to efficiently assess disease resistance among plant materials; however, a number of factors may govern the efficacy of such inoculations. Despite the rapidity at which HLB can spread in a grove, it often takes 8 to 10 months for high levels o