Construction and analysis of a SSH cDNA library of Eucalyptus grandis × Eucalyptus urophylla 9224 induced by Cylindrocladium quinqueseptatum

Abstract

Leaf blight caused by Cylindrocladium quinqueseptatum Boedijn & Reitsma is a major disease occurring in Eucalyptus plantlets and saplings worldwide. Current studies on the resistance to this disease in eucalypti have focused primarily on analyzing the relationship between the disease and the metabolic products from the anatomic structure of Eucalyptus leaves and their physiological responses to pathogen invasion. There have been no reports on the mechanisms of molecular responses. Previous research suggests that Eucalyptus grandis ϫ Eucalyptus urophylla 9224 is the highest resistant cultivar among the 11 ones planted in Fujian Province. Therefore, in this study, the molecular responses of E. grandis ϫ E. urophylla 9224 to C. quinqueseptatum were investigated by means of suppression subtractive hybridization (SSH). In total, 928 clones were obtained from the forward SSH cDNA library of E. grandis ϫ E. urophylla 9224, and 25 up-regulated genes were identified by screening the library using the method of reverse northern hybridization. The results show that among these, 23 up-regulated genes with known functions were involved in signal transduction, plant resistance response, photosynthesis, energy transfer, protein metabolism, and plant growth.Résumé : La brûlure foliaire causée par le Cylindrocladium quinqueseptatum Boedijn & Reitsma constitue une maladie majeure chez les plantules et les jeunes arbres d'Eucalyptus, partout au monde. Les études courantes sur la résistance à cette maladie des eucalyptus se concentrent surtout sur l'analyse de la relation entre la maladie et les produits métaboliques de la structure anatomique des feuilles d'Eucalyptus et de leurs réactions physiologiques à l'invasion par le pathogène. Il n'y a pas de document sur les mécanismes des réactions moléculaires. Une recherche antécédente suggère que l'Eucalyptus grandis ϫ Eucalyptus urophylla 9224 constituerait le cultivar le plus résistant parmi les 11 plantés dans la province de Fujian. Conséquemment, dans leur étude, les auteurs ont examiné les réactions moléculaires de l'E. grandis ϫ E. urophylla 9224 envers le C. quinqueseptatum à l'aide de la suppression par hybridation soustractive (SHS). Au total, ils ont obtenu 928 clones à partir de la librairie SHS cADN directe de l'E. grandis ϫ E. urophylla 9224, et ils ont identifié 25 gènes activés en balayant la librairie à l'aide de la méthode d'hybridation northern inverse. Les résultats montrent que parmi ceux-ci, 23 gènes activés ayant des fonctions connues sont impliqués dans la transduction du signal, la réaction de défense de la plante, la photosynthèse, le transfert d'énergie, le métabolisme des protéines et la croissance de la plante.

A catalog of annotated high-confidence SNPs from exome capture and sequencing reveals highly polymorphic genes in Norway spruce (Picea abies)

“…Both HSP families were reported as highly polymorphic in Picea sitchensis [81], and the Hsp20/alpha crystalline family was also found highly polymorphic in P. glauca [26]. Finally, the most SNPed gene across the whole dataset was found to encode a Phytanoyl-CoA dioxygenase (Additional file 3), which was previously shown to be involved in the electron transfer in Eucalyptus resistance response against Cylindrocladium [82].…”

Transcriptomic Analysis of Calonectria pseudoreteaudii during Various Stages of Eucalyptus Infection

“…C . pseudoreteaudii inoculation was performed as described previously [14]. For studying the infection process, leaves inoculated with conidia suspension were sampled at 4, 6, 8, 12, and 24 hours post inoculation (hpi).…”

Uncovering the defence responses of Eucalyptus to pests and pathogens in the genomics age

“…Much of the data produced from these studies is publicly available and has been used to describe various aspects of Eucalyptus biology. In addition, a number of studies have used expression-based data from Suppressive Subtractive Hybridisation (SSH) studies, EST libraries and microarrays to infer defence responses in Eucalyptus (Duplessis et al 2005;Feng et al 2012;Rosa et al 2010). The Eucalyptus Genome Network (EUCAGEN, web.up.ac.za/eucagen/) is a consortium of researchers aimed at the development of Eucalyptus genomic resources and provides links to various useful sites and tools for this field.…”