Almond crop yields threatened by disease new to California

Detection of fungus causing red leaf blotch spurs call for grower vigilance
Symptoms of red leaf blotch (RLB), a plant disease caused by the fungus Polystigma amygdalinum, have been observed for the first time in California across the northern San Joaquin Valley.
Molecular DNA testing by the laboratory of Florent Trouillas, University of California Cooperative Extension fruit and nut crop pathology specialist, has confirmed the detection of P. amygdalinum. Formal pest confirmation by the…