|Castell, C - UNIVERSITY OF MINNESOTA|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: August 25, 2001
Publication Date: June 1, 2001
Citation: CASTELL, C., SAMAC, D.A. MOLECULAR VARIABILITY OF PHOMA MEDICAGINIS VAR. MEDICAGINIS. PHYTOPATHOLOGY. 2001. V. 91. P. 513. Technical Abstract: Spring Black Stem and Leaf Spot of alfalfa caused by Phoma medicaginis Malbr. &;Roum. var. medicaginis Boerema, is a world-wide disease causing significant yield and quality losses in alfalfa. The fungus attacks leaves, petioles, stems, crown, roots, and pods. Tissue specific pathogenicity and molecular variation within and among populations in Minnesota have not been nstudied. The objectives of this project are: 1) to compare DNA sequences o the rDNA internal transcribed spacers (ITS) 1 and 2 of isolates from leaves and crowns of alfalfa plants, and 2) to determine variability in a large collection of single spore isolates obtained from different alfalfa tissues collected from northern and southern areas of Minnesota by using amplified fragment length polymorphism (AFLP). Sequencing of ITS 1 and 2 showed that these regions are highly conserved at the species level. Preliminary studies using AFLP showed polymorphism between isolates from different areas and isolates from leaves and crowns. These studies may be useful in developing screens for resistant alfalfa varieties to the foliar and crown rot phase of the disease.