Root pathogen

Antibiotic substances and their molecular genetics are summarized for the best studied system of fluorescent Pseudomonas, producing up to. seven different compounds. Similar extensive studies should be done for other important rhizosphere bacteria as potential important antagonists for root pathogens. The best-studied example for the effects of vitamins in the rhizosphere is biotin. The molecular genetics of production and uptake of vitamins in the plant-microbe interaction is also a field of interesting future work. 

Yousef LF, Bernards MA (2006) In vitro metabohsm of ginsenosides by the ginseng root pathogen Pythium irregulare. Phytochemistry 67 1740... 

Whipps JM, Prospects and limitations for mycorrhizas in biocontrol of root pathogens. Can J Botil A 198—1227, 2004. 

Apple Organic soil amendments that promote soil microbial diversity Higher growth scores and lower colonisation by root pathogens Pythium sp., Rhizoctonia solani) Manici et ai. (2003)... 

Keel, C., Ddfago, G. Interactions between beneficial soil bacteria and root pathogens mechanisms and ecological impact. In, Multitrophic Interactions in Terrestrial Systems. Gange A.C., Brown, V.K. eds. Blackwell Science Ltd. London, UK, 1997 pp. 27-46. 

O Sullivan, D.J., O Gara, F. Traits of fluorescent Pseudomonas spp. involved in suppression of plant root pathogens. Microbiol Rev 1992 56 662-676. 

Many studies show that AM fungi initiate a host defence response which is subsequently suppressed (Lambais and Mehdy, 1993 Volpin et al. 1994, 1995). The decreases were accompanied by differential reductions in the levels of mRNAs encoding for different endochitinase and endoglucanase isoforms. But the activation of specific plant defence reactions by AM fungi could predispose the plant to an early response to attack by a root pathogen (Gianinazzi-Pearson et al., 1994). 

Neswham K.K., Fitter A.H. Watkinson A.R. Arbuscular mycorhriza protect an annual gras from root pathogenic fungi in the field. J Ecol 1995 83 991-1000. 

Trotta A., Varese G.C., UNAVI E., Fusconi A., Sampo S., Berta G. Interactions between the soil-borne root pathogen Phytophthora nicoticmae var parasitica and arbuscular mycorrhizal fungus Glomus mosseae in tomato plants. Plant Soil 1996 185 199-209. 

Root pathogens occur also in non-crop vegetation. For example, Phy-tophtora cinnamoni which causes root rot of many woody species, is widespread in native forests in Australia and has caused the death of almost... 

ERBILGIN, N., RAFFA, K.F., Association of declining red pine stands with reduced populations of bark beetle predators, seasonal increases in root colonizing insects, and incidence of root pathogens. For. Ecol. Manage., 2002,164, 221-236. 

Figure 8.4 Digital images of ectomycorrhizal mycelial systems of (a) Suillus bovinus and (b) Paxillus involutus in peat microcosms (in association with Pinus sylvestris) (c) the pine root pathogen Rhizina undulata extending from a 50 cm section of pine stem (d) Armillaria ostoyae extending from a 8cm pine wood resource across nonsterile soil compacted in 24 cm X 24 cm trays.

Armillaria ostoyae Tree root pathogen, rhizomorph former Basidiomycota Agar, at different times during colony development to 116h Box counting )bm = 1-43-1.57 [33]... 

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