Rots, brown/soft/white

Takahashi, M., Imamura, Y. and Tanahashi, M. (1989). Effect of acetylation on decay resistance of wood against brown rot, white rot and soft rot fungi. International Research Group on Wood Preservation, Doc. No. IRGAVP 3540. 

All laboratory tests for biological resistance conducted to this point show that acetylation is an effective means of reducing or eliminating attack by soft-, white-, and brown-rot fungi, tunneling bacteria, and subterranean termites. Tests are presently underway on several lignocellulosic composites in outdoor environments. 

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 yeUow and wilted. Causes Fusar-ium bulb rot onion maggots lesser bulb flies wireworms. Onions infected with Fusarium bulb rot have soft necks, and entire bulbs may be soft and brown. Destroy infected plants. Prevent problems by planting cultivars, such as Long White Summer Bunching , Northern Oak , Sentinel , and Valiant , that are somewhat resistant. 

Soft rot is of economic significance mainly under conditions that retard or inhibit the activities of brown and white rot fungi, e.g. in preservative treated wood, in thermophilic situations and aquatic environments. This slow and initially superficial rot is sometimes more significant than might appear at first sight for several reasons ... 

Fungal Decay of Woods. Blocks of NaOH-treated and untreated sugar maple were inoculated with three test fungi—a brown, a white, and a soft rot—by the standard soil-block method (8). At various intervals, the test blocks were removed, the fungal growth washed off, the block sterilized, and ovendried to obtain weight losses. 

Soft rot is a type of decay caused by ascomycetes and Fungi Imperfecti. The term soft rot was proposed by Savory (54) for a form of fungal decay where characteristic chains of cavities with conical ends were produced within wood cell walls. He recommended that the term soft rot should be used for decay caused by cellulose-degrading microfungi to distinguish it from the brown and white rots caused by the wood-destroying basidiomycetes. ... 

Waterlogging will exclude white- and brown-rot basidiomycetes. Soft rot may still be active, although at limiting oxygen levels only bacteria are able to degrade wood. 

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. 

Watery soft rot caused by S. sclerotiorum and S. minor often develops on tubers that appear sound at harvest but subsequently succumb in storage (Gaudineau and Lafon, 1958). The tubers become covered with a dense white mycelium and irregular sclerotia, which progress from white to dark brown or black. Though storage at low temperatures repressed development, S. sclerotiorum can cause serious losses at low temperature (Johnson, 1931). 

Types of Decay. As shown in Figure 3, wood decay fungi can be divided into three classes based on the type of decay they cause white, brown, and soft rots. The white rots can be further separated into pocket rots and uniform rots (Figure 3). In North America, the white and brown rots are caused by about 1700 species of wood-decaying fungi in the class Basidiomycetes over 90% of these cause the white rot type of decay (67). Early reports of non-basidiomycete... 

Macroscopic and microscopic characteristics of white, brown, and soft rots are summarized in Table IV. 

Table IV. Macroscopic and Microscopic Features of White, Soft, and Brown Rots of Wood...

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