Citrus sinensis non-host response to Xanthomonas campestris pv. vesicatoria involves photosynthesis decline, abiotic stress networks and secondary metabolism modifications

DAURELIO, LUCAS D.; TONDO, M. LAURA; ROMERO, M. SOLEDAD; MERELO, PAZ; CORTADI, ADRIANA A.; TALÓN, MANUEL; TADEO, FRANCISCO R.; ORELLANO, ELENA G.

FUNCTIONAL PLANT BIOLOGY

CSIRO PUBLISHING

Lugar: Collingwood; Año: 2015 vol. 42 p. 758 - 769

1445-4408

Plants are constantly exposed to stress factors. Biotic stress isproduced by living organisms such as pathogens, whereas abiotic stress byunfavourable environmental conditions. In Citrus species, one of themost important fruit crops in the world, these stresses generate seriouslimitations in productivity. Through biochemical and transcriptomic assays, wehad previously characterised the Citrus sinensis (L.) Osbeck nonhostresponse to Xanthomonas campestris pv. vesicatoria (Doidge), incontrast to Asiatic citrus canker infection caused by Xanthomonas citri subsp.citri (Hasse). A hypersensitive response (HR) including changes in theexpression of several transcription factors was reported. Here, a newexhaustive analysis of the Citrus sinensis transcriptomes previouslyobtained was performed, allowing us to detect the over-representation ofphotosynthesis, abiotic stress and secondary metabolism processes during the nonhostHR. The broad downregulation of photosynthesis-related genes was correlatedwith an altered photosynthesis physiology. The high number of heat shockproteins and genes related to abiotic stress, including aquaporins, suggeststhat stresses crosstalk. Additionally, the secondary metabolism exhibitedlignin and carotenoid biosynthesis modifications and expression changes in thecell rescue GSTs. In conclusion, novel features of the Citrus nonhostHR, an important part of the plants? defence against disease that has yet to befully exploited in plant breeding programs, are presented.