Sclerotinia sclerotium

Disease resistance represents one of the more difficult traits for selection. The primary diseases impacting Jerusalem artichoke production are sclerotinia wilt/rot (Sclerotinia sclerotiorum (Lib.) de Bary), rust (Puccinia helianthi Schw.), southern wilt/blight/collar rot (Sclerotium rolfsii Sacc.), and powdery mildew (Erysiphe cichoracearum DC.) (see Chapter 11). The importance of each disease is dependent upon the production site. For example, in Europe, sclerotinia is a critical disease, while rust and southern wilt are important diseases in North American production areas. Powdery mildew tends to be less important, in that Jerusalem artichoke appears to have reasonable levels of endogenous resistance. 

Kuhn, Sclerotinia sclerotiorum (Lib.) de Bary and Sclerotium rolfsii Sacc.). It was demonstrated that S. sclarea essential oil had a lethal effect on five of the six pathogens tested the most susceptible microorganisms were B. cinerea and S. rolfsii (MIC between 1.3 and 1.6 mg/ml) while Fu-sarium solani was insensitive (MIC >5.4 mg/ml). The chromatographic fractions were less active compared with essential oil in toto. The most marked inhibitory action was observed with the alcohol-containing fractions. All in all, these observations indicate that further research should be done to evaluate both the synergic action of the components of the different fractions and the activity of the essential oil in toto, when applied directly to the plant species infected by the fungi, in suitable formulations. 

Yang, X.B. E Workneh P. Lundeen. First report of sclerotium production by Sclerotinia sclerotio-rum in soil on infected soybean seeds. Plant Dis. 1998, 82, 264. 

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