sapstain fungi of some commercially important timbers and their ...

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RESULTS AND DISCUSSIONThe common stain causing fungi isolated from different timber speciessuch as Hevea brasiliensis, Ailanthus triphysa, Bombax ceiba, Alstonia scholaris, Mangiferaindica, Anacardium occiden tale, Macaranga peltata and Erythrina s tricta wereBotryodiplodia theobrontae, Ceratocystis fimbriata, Acremoniumspp., Scytalidium lignicolaand Fusarium spp. of which B. theobromae was the most dominant on causing stain(Figs. 3, 4). B. theobrontae was reported as the most prevalent sapstain fungus ontropical woods (Cartwright and Findlay, 1958; Olofinboba, 1974; Hong, 1976). Itwas also known to cause sapstain in rubber wood in Malaysia (Ali et al., 1980).
Ceratocystis fimbriata was prominently found causing stain in rubber wood duringrainy season in Kerala. Ceratocystis coerulescens was reported as the most importantstain fungus on hardwoods in the southern USA (Verrall, 1941). In Russia,Cera tocystis spp. were responsible for the discolouration of the wood (Vanin,1932). C. picea, normally a nonstaining fungus on conifers in the western USA,caused stain in red Alder (Alnus rubra) (Morrell, 1987). Several species of Ceratocystiswere reported to cause stain on pine wood in Spain (Troya and Navarrete, 1989).The fungi isolated from the surface of different timber species surveyedwere Aspergillus niger, A. flavus, Penicillium spp., Trichoderma viride, Memnoniellaechinata, Syncephalastrum racemosum Cohn ex Schrot., Cladosporium sp., Mucor sp.,and Absidia corymbifera (Cohn) Sacc. & Trotter, of which Aspergillus spp., Penicilliumspp., T. viride, S. racemosum and Mucor sp., were the dominant ones (Fig. 5).M. echinata was seen more on rubber wood (Fig. 6).The results of the survey indicated that there was no definite pattern inthe occurrence of mould and sapstain on different timber species collected. Alltimber species surveyed were found to be susceptible to B. fheobromae; H. brasiliensisbeing the most severely and frequently affected. Based on the frequency ofisolation of B. theobromae, it can be concluded that timbers such as H. brasiliensis,A. occidentale, Artocarpus spp. and A. triphysa were the most susceptible ones whileM. indica, B. ceiba and E. stricta moderately susceptible; least susceptible timberswere A. scholaris, and M. peltata (Table 3).Table 3.Frequency percentage of Botryodiplodia theobromae in fungalisolations made from various timbers of Kerala.Timber Total No.of Frequency of Number of monthsspecies isolations infection samples collectedpercentage in a yearAilanthus triphysaAlstonia scholarisAnacardium occidentaleArtocarpus spp.Bombax ceibaCeiba pentandraErythrina strictaHevea brasiliensisMacaranga pelta taMangifera indica1311131143756622357018777540426081275776647533149
Page 4 and 5: INTRODUCTIONFungi cause different k
Page 6 and 7: MATERIALS AND METHODSSurveyA prelim
Page 8 and 9: Table 1 Relative humidities over sa
Page 10 and 11: Optimum moisture content of wood fo
Page 13: Treatment 1 : Dipping and stacking
Page 18 and 19: Table 5Percentage of weight loss du
Page 20 and 21: Table 7Growth rating of B.theobroma
Page 22 and 23: y the boron diffusion process and f
Page 24 and 25: Table 11 Percent control of fungal
Page 26 and 27: -Table 12 Inhibitory zone (in mm) p
Page 28 and 29: CONCLUSIONS1. Botryodiplodia theobr
Page 30 and 31: Colley, R. H. and Rumbold, C. T. 19
Page 32: Verrall, A. F. 1941. Fungi associat

sapstain fungi of some commercially important timbers and their ...

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