Project description:With the aid of a biochip, carrying representative sequences from approximately 2200 sequences from the genome of isolate 9a5c from X. fastidiosa (Xf), microarray-based comparisons have been performed with 6 different Xf isolates obtained from citrus plants (Table 1). Four of these isolates (56a, 9.12c, 187b, and 36f) were obtained from CVC-affected trees and are representatives of the most prevalent Xf haplotypes found in sweet orange orchards across the state of São Paulo, while isolate CV21 was obtained from a non-symptomatic tree from the same region. Isolate Fb7, on the other hand, was obtained from a sweet orange tree that displayed symptoms of “Pecosita”, a disease similar to CVC that occurs in some citrus-growing regions of Argentina. Keywords: Comparative Genomic Hybridization
Project description:Citrus greening or huanglongbing (HLB) is a devastating disease of citrus. HLB is associated with the phloem-limited fastidious prokaryotic alpha-proteobacterium Candidatus Liberibacter spp. In this report, we used sweet orange (Citrus sinensis) leaf tissue infected with 'Ca. Liberibacter asiaticus' and compared this with healthy controls. Investigation of the host response was examined with citrus microarray hybridization based on 30,171 sets expressed sequence tag sequences from several citrus species and hybrids. The microarray analysis indicated that HLB infection significantly affected expression of 624 genes whose encoded proteins were categorized according to function. The categories included genes associated with sugar metabolism, plant defense, phytohormone, and cell wall metabolism, as well as 14 other gene categories.
