Characterization of Trichoderma Isolates from Philippine Rice Fields by UP‐PCR and rDNA‐ITS1 Analysis: Identification of UP‐PCR Markers

Abstract

Forty‐two isolates of Trichoderma from rice fields in four provinces in the Philippines were characterized using rDNA‐ITS1 analysis and universally primed polymerase chain reaction (UP‐PCR). Two groups were clearly distinguishable on the basis of length and restriction pattern of the internal transcribed spacer (ITS) region of the ribosomal DNA and UP‐PCR banding profiles using UP primer, L45. The 40 isolates comprising the largest group were very similar with respect to their UP‐PCR banding profiles and were assigned to Trichoderma harzianum Rifai following morphological identification of four of the isolates. The two isolates belonging to the second group were identified as Trichodermaviride Pers. ex. Gray on the basis of their morphology, rDNA‐ITS1 analysis and distinct UP‐PCR banding profiles. One of the T. harzianum isolates with good cellulolytic and competitive saprophytic abilities was analysed using single and pair‐wise combinations of UP primers in order to distinguish it from the remaining 41 isolates. A suitable diagnostic marker was identified and this marker will be valuable for monitoring the isolate in field tests.

DNA fingerprinting and anastomosis grouping reveal similar genetic diversity inRhizoctonia speciesinfecting turfgrasses in the transition zone of USA

“…UP-PCR analysis is relatively inexpensive compared to other techniques and is an accurate and efficient method to characterize a large number of unknown Rhizoctonia isolates into their respective AG groups and subgroups. The clusters formed by this method largely agreed with the results of well documented ITS sequence analysis (Kuninaga et al 1997, Gonzalez et al 2001, Hsiang and Dean 2001, Toda et al 2005, de la Cerda et al 2007.…”

“…Successful primers were tagged with fluorescent dye 6-FAM to facilitate data collection on the Applied Biosystems 3730 Genetic Analyzer. The primers L45 (59-GTAAAACGACGGCCAGT-39), L15/AS19 (59-GAGGG TGGCGGCTAG-39), AS15 (59-GGCTAAGCGGTCGTTAC-39), and L21(59-GGATCCGAGGGTGGCGGTTCT-39) (Cumagun et al 2000, Lü beck and Lü beck 2005) were tested. The UP-PCR was performed in a PTC-200 thermo-cycler (MJ Research, Ramsey, Minnesota).…”

“…oryzae Warcup and Talbot) are responsible for leaf and sheath spot disease. Unlike other Rhizoctonia diseases, yellow patch caused by R. cerealis van der Hoeven (teleomorph: Ceratobasidium cereale Murray and Burpee; anastomosis group: AG-D) favors cool and wet weather (Smiley et al 2005, de la Cerda et al 2007). Another recently identified causal agent, Waitea circinata var.…”

“…Another recently identified causal agent, Waitea circinata var. circinata, is responsible for brown ring patch in golf courses (de la Cerda et al 2007). All aforementioned species have multinucleate cells except R. cerealis, which is a binucleate species.…”

Trichoderma populations from alkaline agricultural soil in the Nile valley, Egypt, consist of only two species

“…harzianum is probably the genetically most diverse taxon of the genus. Kubicek, M. Lübeck, unpublished data; see also CUMAGUN et al 2000), and Austria (WUSZKOVSKY et al 2003). In this context, it is interesting that the T. harzianum haplotypes found in this study are rare: one (2c) has not been found before.…”