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Candidatus liberibacter spp and its vectors

Virgen Calleros G., Fernández Rivera E., Reyes Hernández J., Medina Urrutia V., y de La Paz Gutiérrez S.

Department of Agricultural Production. University Institute of Biological and Agricultural Sciences. University of Guadalajara

HLB (Huanglongbing), a disease caused by the bacterium Candidatus Liberibacter asiaticus (Ca. L. a.), is doubtless the most important citrus disease worldwide, causing substantial losses in yields from the majority of citrus plants.

HLB (Huanglongbing), a disease caused by the bacterium Candidatus Liberibacter asiaticus (Ca. L. a.), is doubtless the most important citrus disease worldwide, causing substantial losses in yields from the majority of citrus plants. The bacterium is transmitted by the Asian citrus psyllid (Diaphorina citri Kuwayama). Two other species of bacteria affect citrus, although they are less widely distributed; Ca. Liberibacer africanus, found in Africa and transmitted by Trioza erytreae, and Ca. Liberibacter americanus, transmitted by D. citri in Brazil. However, it has also been reported that Ca. L. asiaticus can be found in other species of psyllids such as D. communis and Cacopsylla citrisuga, although transmission studies have not been carried out.

Management strategies for this disease include eliminating infected plants, planting healthy trees, and eradicating the vector. Recently, however, minerals have been applied to reduce HLB severity and increase resistance to the disease. In addition, studies of tree phenology and of the population dynamics of the vector may help pinpoint the most appropriate time to apply control measures.

In Mexico, the Persian lime (Ctrius latifolia) is grown on 153,442.62 hectares across 19 Mexican states, producing 1,891,403.15 tons per year at an average yield of 13.15 t/ha. The state of Veracruz is the largest producer of the Persian lime in Mexico, with cultivation occupying 36,257.36 ha, while in the state of Jalisco the crop is grown on nearly 4,500 ha, primarily in three regions: highlands, valleys, and the southern coast.

HLB was first reported in Mexico in 2009 in the state of Yucatán and has since been detected in other areas of the country. Diaphorina citri is the only known vector of the disease in the country, and in Jalisco peak population levels of the vector occur during the budding period of the Persian lime; in the valley region, the peak Diaphorina citri population was found from mid-July to late August, coinciding with the sprouting of new buds. In addition to the application of macronutrients (N, P, and K), mineral-based management of this disease includes the use of silicon, which has led to lower disease severity and higher yields, quality, and chlorophyll content. Cross-sectioning of the leaf veins of silicon-treated plants examined using an optical microscope revealed increased phloem size relative to controls.

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PRODECA guarantees that you may, at any time, exercise your right to access, rectify, cancel or oppose by writing to the aforesaid postal address, using the reference "PROTECCIÓN DE DATOS - SMARTFRUIT", or to the email address smartfruitcongress@smartfruitcongress.cat.

Specifically, to correctly exercise these rights you must clearly provide the following items in that communication:
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PRODECA also declares that it reserves the right to delete from its website any content that it considers violates current and applicable legislation.

D’acord amb l’article 17.1 de la Llei 19/2014, la ©Generalitat de Catalunya permet la reutilització dels continguts i de les dades sempre que se'n citi la font i la data d'actualització i que no es desnaturalitzi la informació (article 8 de la Llei 37/2007) i també que no es contradigui amb una llicència específica.