Archivio Journal of Plant Pathology

Abstract:

Tower tree Schizolobium parahybum is a common ornamental plant in Malaysia In 2013 a tower tree at Kota Damansara Selangor Malaysia 3151177N 1015710143W showed leaf yellowing and shoot dieback The tree died 46 months after the first manifestation of symptoms Whitish mycelium was first observed near the basal collar above the roots followed by the growth of a blackish brown bracketlike sessile nonlaccate basidiocarp Most of the other morphological characteristics of the basidiocarp were similar to those observed by LoguercioLeite et al 2005 Basidiospores were bitunicate 85011x4162 μm ellipsoid or ovoid truncate at apex frequently containing one big oil drop Radial growth rate of mycelium on malt extract agar MEA at 24°C was 23±1 mm/day whereas under anaerobic conditions at 24°C BD GasPakTM EZ anaerobic container system sachets it was 16 mm/day Genomic DNA was extracted FastDNA Spin kit MP Biomedicals USA from a pure isolate the 18S rDNA region was amplified using the NS1/NS8 primer set and sequenced Macrogen Korea Following BLAST analysis the sequence accession No KF925451 obtained from pure culture showed 98% similarity with G australe accession No AY336763 a pathogen reported to infect Acacia in Thailand Bao and Lenné 1994 and Lagerstroemia in China Cui et al 2008 To the best of our knowledge this is the first report of G australe in Malaysia associated with a tower tree disease Farr and Rossman 2013 A new tower tree planted on the same site upon removal of the infected plant also became diseased A whitish mycelium developed after approximately 12 months while foliar symptoms appeared after 34 months from plantingPARAHYBUM IN MALAYSIA