Stem-pitting caused by Citrus tristeza virus is associated with increased phloem occlusion.

Stem-pitting (SP) disease results from disruption of normal phloem and xylem development. In citrus, a characteristic manifestation of SP caused by Citrus tristeza virus (CTV) is phloem regeneration. We hypothesized that phloem regeneration occurs due to reduced functionality of CTV infected phloem cells.

Comparative transcriptome analysis of tree infected with stem pitting mutants provides new insight into the role of phloem regeneration in stem pitting disease.

Stem pitting is a complex and economically important virus-associated disease of perennial woody plants. Molecular mechanisms and pathways occurring during virus-plant interaction that result in this phenomenon are still obscure. Previous studies indicated that different (CTV) mutants induce defined stem pitting phenotypes ranging from mild (CTVΔp13) to severe (CTVΔp33) in trees.

Functional study of CHS gene family members in citrus revealed a novel CHS gene affecting the production of flavonoids.

Background: Citrus flavonoids are considered as the important secondary metabolites because of their biological and pharmacological activities. Chalcone synthase (CHS) is a key enzyme that catalyses the first committed step in the flavonoid biosynthetic pathway. CHS genes have been isolated and characterized in many plants.

A 5'-proximal region of the Citrus tristeza virus genome encoding two leader proteases is involved in virus superinfection exclusion.

Superinfection exclusion (SIE), a phenomenon in which a primary virus infection prevents a secondary infection with the same or closely related virus, has been observed with various viruses. Earlier we demonstrated that SIE by Citrus tristeza virus (CTV) requires viral p33 protein. In this work we show that p33 alone is not sufficient for virus exclusion.

Marker-Assisted Selection of Tomato Genotypes with the I-2 Gene for Resistance to Fusarium oxysporum f. sp. lycopersici Race 2.

Fusarium vascular wilt, caused by Fusarium oxysporum f. sp. lycopersici, affects tomatoes worldwide.