Root rot

Fusarium oxysporum fsp. radicis-lycopersici Jarvis and Shoemaker (FORE) (Jarvis and Shoemaker, 1978) [1] is a pathogen of tomato which, with the arrival of intensive tomato culture under glass, has developed to serious proportions [2]. This forma specialis of F. oxysporum affects largely the root and crown tissues of tomato and the symptoms occur as foot and root rot. FORL isolates are pathogenic on tomato plants with genes for resistance to races 1 and 2 of Fusarium oxysporum Schlecht. fsp. lycopersici (Sacc.) Snyd. Hans (FOL), that cause the common Fusarium wilt of the tomato. However, although resistance to FORL has been found and incorporated into commercial cultivars, the disease is a severe problem in wide areas of the North Hemisphere [3-9]. 

Chin-A-Woeng TFC, GV Bloemberg, IHM Mulders, LC Dekkers, BJJ Lugtenberg (2000) Root comonization by phenazine-l-carboxamide-producing bacterium Pseudomonas chlororaphis PCL 1391 is essential for biocontrol of tomato foot and root rot. Mol Plant-Microbe Interact 13 1340-1345. 

Pseudomonas fluorescens CHAO HCN. 2,4-Diacetylphlo roglucinol, pyoluteorin Thielviopsis basicola Tobacco Black root rot 118... 

C. Voisard, C. Keel, D. Haas, and G. Defago, Cyanide production by P.seudomonas fluorescens helps suppress black root rot of tobacco under gnotobiotic conditions, EM BO J 8 35 (1989). 

M. N. Schroth and W. C. Snyder, Effect of host exudates on chlamydospore germination of the bean root rot fungus Fusarium solani f. phaseoli. Phytopathology 51 389 (1961). 

S. A. Omar and M. H. Abd-Alla, Biocontrol of fungal root rot diseases of crop plants by the use of Rhizobia and Bradyrhizobia. Folia Microbiol. 45 431 (1998). 

After introducing recommended amounts of terbutrin and chlortoluron, wheat suffered more seriously from downy mildew. Monolinuron and simazin affected winter wheat similarly. Herbicides such as 2,4-MCPA, ioxynil, dicamba, and several others increased the amount of root rot damage to winter wheat on average by 60% when compared with the control crop. Treating grain crops using... 

In many cases, the incorporation of organic matter in the soil may be a beneficial alternative to chemicals for plant disease control. Lor example, Viana et al. (2000) reported that matured cattle manure and sugarcane husks are efficient alternatives for control of bean damping-off (Sclerotinia sclerotiorum). Larmyard manure applied at 5 t/ha once every three years reduced dry root rot (Macrophominaphaseolina) to 32% in groundnut (Arachis... 

Feld, S.J., Menge, J. A. and Stolzy, L.H. (1990). Influence of drip and furrow irrigation on Phytophthora root rot of citrus under field and greenhouse conditions , Plant Disease, 74, 21-27. 

Harinath, N.P. and Subbarami, R.M. (1996). Effect of soil amendments with organic and inorganic manures on the incidence of dry root rot of groundnut , Indian Journal of Plant Protection, 24, 44 16. 

Field soil solarization was effective in dramatically reducing or completely eliminating the infection of Pythium spp. in carrot (Daucus carota L.) and strawberry roots (Becker and Wrona 1995 Pinkerton et al. 2002), as well as reduced inoculum levels of P. aphanidermatum in watermelon and potato down to 25-30 cm soil depth (Mansoori and Jaliani 1996 Triki et al. 2001). Summer soil solarization in greenhouse reduced Pythium root rot even in the temperate climate of Denmark (Christensen and Thinggaard 1999). 

Benson DM (1978) Thermal inactivation of Phytophthora cinnamomi for control of Fraser fir root rot. Phytopathology 68 1373-1376... 

Chellemi DO (2006) Effect of urban plant debris and soil management practices on plant parasitic nematodes Phytophthora blight and Pythium root rot of bell pepper. Crop Prot 25 1109-1116. doi 10.1016/j.cropro.2006.02.012... 

Christensen LK, Thinggaard K (1999) Solarization of greenhouse soil for prevention of Pythium root rot in organically grown cucumber. J Plant Pathol 81 137-144 Chun D, Lockwood JL (1985) Reduction of Pythium ultimum, Thielaviopsis basicola, and Macrophomina phaseolina populations in soil associated with ammonia generated from urea. Plant Dis 69 154-158... 

Root rots occur widely, but no chemical control program is in practice. Water soaking and drying out of seed pieces are serious problems at times. 

Rosellinia. Among cacao root rots, that caused by the Rosellinia fungus is a sporadic disease that occurs mainly in poorly drained soils. 

Root Rots in Transplanting. Transplanting losses are high, mainly due to root decaying organisms. There is need for studies of chemical root treatment before transplanting. 

In the Far East, on the whole, the most troublesome hevea rubber diseases are root decays. It is commonly realized (4, 11, 35, 36, 40, 42, 43, 45) that, left unchecked, rubber root rots would have very soon destroyed commercial production of plantation rubber in the Orient. There is no tree crop that has had its many root rot diseases given such thorough study as has rubber. E. W. Brandes, R. D. Rands. Theodore J. Grant, E. P. Imle, and John B. Carpenter agreed that these troubles have been of practically no concern in tropical America. Langford (19) found little root rot trouble in his considerable observations specifically on rubber in the Western Hemisphere. 

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