Host Specificity of a Brazilian Isolate of Alternaria cassiae (Cenargen CG593) Under Greenhouse Conditions

• Published in: Phytoparasitica 2007-03, Vol.35 (2), p.123-128
• Main Authors: Pitelli, R.L.C.M, Penariol, M, Pitelli, A.M.C.M, Pitelli, R.A
• Format: Article
• Language: English
• Subjects: Alternaria cassiae; biological control; biological control agents; broadleaf weeds; cassava; dew; disease incidence; eggplants; fungal diseases of plants; greenhouse production; host range; host specificity; Lycopersicon esculentum; Manihot; Manihot dulce; Manihot esculenta; Melongena; mycoherbicides; plant growth; Senna obtusifolia; Solanum lycopersicum var. lycopersicum; Solanum melongena; tomatoes; weed control
• ISSN: 0334-2123; 1876-7184
• DOI: 10.1007/BF02981105

Several Alternaria cassiae isolates were recovered from diseased sicklepod plants (Senna obtusifolia) in the southern regions of Brazil. A representative isolate (Cenargen CG593) was tested for its host range under greenhouse conditions. The fungus promoted symptoms in sicklepod, cassava (Manihot dulce), tomato (Lycopersicon esculentum) and eggplant (Solatium melongena) when tested at a spore concentration of 10 super(6) spores ml super(-1). When the plants were inoculated with a suspension of 10 super(5) spores ml super(-1) and held at a dew period of 12 h (cassava) or 18 h (tomato and eggplant), the plants showed symptoms of the disease, but they recovered and continued their normal vegetative growth. These results show that the fungus A. cassiae is safe to use for the control of 5. obtusifolia under Brazilian conditions, because it did not cause excessive damage in the three plants tested.