Jk. Bowen et al., DIFFERENTIATION OF A SPECIFIC TRICHODERMA BIOLOGICAL-CONTROL AGENT BYRESTRICTION-FRAGMENT-LENGTH-POLYMORPHISM (RFLP) ANALYSIS, New Zealand journal of crop and horticultural science, 24(3), 1996, pp. 207-217
A single biological control isolate belonging to the species aggregate
Trichoderma harzianum Rifai was differentiated from other closely rel
ated Trichoderma species and commonly isolated mycoflora by molecular
assay. Restriction fragment length polymorphism (RFLP) analysis enable
d the differentiation of the single isolate; a hybridising band of 1.1
kb being diagnostic. Cross-hybridisation occurred against the DNA fro
m 12 Trichoderma isolates, representative of three species aggregates.
The hybridisation probe used during the RFLP analysis was an amplific
ation product produced during random amplification of polymorphic DNA
(RAPD) polymerase chain reaction (PCR) analysis using DNA from T. harz
ianum isolate C65 as template. This amplification product was not visi
ble following separation of amplification products generated during PC
R using DNA from a test array of fungi as template. Diagnostic PCR, us
ing primers designed from the sequence of the specific polymorphic amp
lification product failed to discriminate between C65 and other Tricho
derma isolates, since products with equivalent size were generated. Th
e ability to differentiate the isolate of T. harzianum from other clos
ely related fungi will enable monitoring of the specific isolate in fi
eld trials to assess biological control ability.