Journal of Plant Pathology (2003) 85, p. 288 (Cirvilleri et al.)

G. Cirvilleri, A. Gentile, M. Gennari, Z.N. Deng, A. Rizzitano, S. Spina, F. Domina, C. Abbate and R. La Rosa (2003)
Influence of transgenic rolABC citrus plants on root-associated bacteria
Journal of Plant Pathology 85 (4), 288-288
X Meeting, Italian Society for Plant Pathology (poster)
Abstract: Troyer citrange, an important citrus rootstock, was transformed with rolABC genes to modify the growth habitus and possibly the behaviour against pathogens. Twenty-three clones regenerated from independent transformation events and five wild type plants were grown in pots for two years. Morphological and physiological modifications were detected, including dwarfing (up to 50% height reduction) and increase of root system density. Root-associated bacteria and fluorescent Pseudomonads were monitored. Total bacterial population (between log 7 and log 8 CFU/g of roots) was not significantly different between 23 plant clones and five wild types examined. The number of fluorescent Pseudomonads, below the detectable level in four rolABC clones, ranged between log 4.5 and log 8 in all the others rol clones and wild types. No differences in the antagonistic activity against Fusarium solani and Phoma tracheiphila and in the IAA production of 130 fluorescent Pseudomonads were found between transgenic clones and wild types. The composition of the bacterial community, studied by ARDRA fingerprints (Amplified Ribosomal DNA Restriction Analysis), did not shown any significant difference between transgenic and wild type clones. Enzymatic analysis, involving PAL (Phenylalanine Ammonia-Lyase) and PO (Peroxidase) assays, and total phenolic compounds determination were done in root samples. Total phenolic compounds, PAL and PO activities were higher in root samples of transgenic clones as compared to wild types. Investigating root-associated bacteria and potential biocontrol agents on transgenic fruit tree species provides an example for performing risk assessment studies.
Database assignments for author(s): Gabriella Cirvilleri, Ziniu Deng

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
resistance/tolerance/defence of host
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Neocosmospora solani	Citrus (genus)
	Plenodomus tracheiphilus	Citrus (genus)