Bacterial soft rot

Erwinia carotovora spp. carotovora (Jones) Bergey et al. Bacterial soft rot + ... 

Leaves with water-soaked spots rhizomes rotted and soft. Cause Bacterial soft rot. Soft rot attacks during wet seasons in poorly drained soil, entering through wounds in the rhizome made by premature leaf removal or cultivation or carried on the bodies of iris borers. Crowded plants in shady locations are more susceptible to this disease. Infected rhizomes are dry on the outside, but wet, smelly, and slimy inside. This rot may start in the leaves... 

Leaves yellow between veins. Causes Stem rot Fusarium wilt. Symptoms of stem rot, also known as bacterial soft rot, usually appear when temperatures are above 90°F Leaves turn yellow, vines wilt, and the base of stems are black and shiny. Destroy diseased plants. Roots may already be rotted or will rot in storage, so use any healthy potatoes as soon as possible. Prevent problems by planting disease-free plants or tolerant cultivars such as Goldmar . 

Wells, J.M. and Bntterfield, J.E. 1997. Salmonella contamination associated with bacterial soft rot of fresh fmits and vegetables in the marketplace. Plant Disease 81 867-872. 

FIGURE 9.3 Resistance ofp/ p-transgenic tobacco plants (T-SPFLP18-1 and T-SPFLPlO-1) against bacterial soft rot disease caused by E. carotovora subsp. carotovora (Ecc) was observed. 

FIGURE 9.5 Symptoms of bacterial soft rot caused by Ecc (A) and wilt disease caused by Ralstonia solanacearum (B) on p lp-transgenic tomato plants (24-18-7) and wild-type plant (Clnl558a). 

FIGURE 9.6 The bacterial soft rot symptom in the leaves of calla lily caused by Ecc on (A) 8-week old or (B) 4-week-oldp p-transgenic lines (Fa7 and Fa24) and wild-type plants. 

Soft rot symptoms produced by E. chrysanthemi consist of a disorganisation of parenchymatous tissues following the release of bacterial pectinolytic enzymes. The diverse enzymes do not contribute equally to the virulence on a given host and their implication may vary according to the host considered. For instance, inactivation of pelE, pelD, pelA or pern in strain 3937 considerably reduces the virulence on African violets while mutations in pelB or pelC remain ineffective [2]. Pectinolysis is regulated by the transcriptional repressor KdgR, inactive in the presence of pectic inducers. 

Property enhancement by acetylation has been frequently reported over the years in other reconstituted wood products such as flakeboards, particleboards, and fiberboards [8,9,11,12,59-64]. Table 16 shows the laboratory decay test of low-density acetylated particleboards made from perishable albizzia wood. They were resistant to attack by Tyromyces palustris (brown rot), Coriolus versicolor (white rot), and Chaetomium globosum (soft rot) above 12% WPG. These acetylated boards with 20% WPG also exhibited an improved resistance to attack by the destructive Formosan termite, Coptotermes formosanus, in the laboratory. However, their performance was unsatisfactory in the wet tropics with a higher hazard of termite attack. High resistance to fungal and bacterial attack in acetylated southern pine and aspen flakeboards was evidenced in laboratory and fungus cellar tests [12]. 

Plant wilts suddenly. Cause Bacterial wilt. This disease causes a soft rot at the base of the stem, killing plants quickly. Remove and destroy infected plants. Do not replant cosmos in that area. 

Potatoes with a black, rotted ring at stem ends. Cause Bacterial ring rot. Tubers have a soft, light brown ring in the flesh near the skin. See Leaves discolored and puckered or curled on page 188 for controls. 

Bacteria and soft rot fungi are more tolerant of the low oxygen conditions in saturated wood, and in wood that is buried in sediments bacterial decay tends to predominate. Early reports identified unicellular bacteria in foundation piling and shipwreck timbers, but more recently three bacterial decay types in wood cell walls are now recognised - erosion, tunnelling and cavitation bacterial decay. 

Charkowski, A.O. 2009. Decaying signals Will understanding bacterial-plant communication lead to control of soft rot Current Opinion in Biotechnology 20 178-184. 

No specific studies appear to have been carried out on the influence of O2 and CO2 on soft rot. The observations of soft rot in waterlogged wood suggest that the responsible fungi are able to attack wood at levels of oxygen that are too low for wood-degrading basidiomycetes. The absence of soft rot and presence of bacterial attack in samples from certain aquatic environments indicate that bacteria are even more tolerant of low oxygen concentrations. 

It has recently become evident that bacteria cause most of the microbial degradation of timber in sunken ships. Mouzouras et al. 118) describe various forms of bacterial attack that were observed in timber from the Mary Rose. The attack includes tunneling as well as erosion forms. Soft rot was also observed. Kim 105) reported that timber from a wrecked Chinese ship that had been submerged for over 700 years was degraded by soft rot and bacteria. Studies of timber from the Swedish battleship Kronan, which sank in the Baltic Sea in 1676, show that most of the microbial degradation of both oak and pine timber can be attributed to erosion bacteria. Soft rot and attack by tunneling bacteria occurred to a much lesser extent. 

Geoffrey, D. Fungal and bacterial biodegradation white rots, brown rots, soft rots, and bacteria. n Deterioration and protection of sustainable biomaterials, Vol. 1158, ACS Symposium American Chemical Society, USA, 2014, pp. 23-58. 

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