|Williams, Howard - TEXAS A&M UNIVERSITY|
|Puckhaber, Lorraine - TEXAS A&M UNIVERSITY|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: January 13, 2001
Publication Date: N/A
Technical Abstract: Use of T. virens in Pythium control may be limited by the ability to grow at cool temperatures. The aim of this research was to combine cold- tolerance from Trichoderma atroviride with activity against P. ultimum from T. virens. A stable cold-tolerant fusant strain that was able to grow at 10 degrees C was obtained. It produced conidia similar to those of the T. atroviride parent but like the T. virens parent was more tolerant to the fungicide fludioxonil. It did not make antibiotics known to be produced by the T. virens parent; however, it did produce 6-pentyl- 2H-pyran-2-one, an antibiotic found in the T. atroviride parent and effective against P. ultimum. The fusant also produced an antibiotic, tentatively identified as viridiofungin A (VA), along with related compounds. We did not detect VA in either parent. VA and a related compound had antifungal activity against Rhizoctonia solani. The fusant also produced several antibiotics that inhibited Bacillus subtillis that were not produced by either parental strain.