PATHOLOGIACL STUDIES ON Alternaria brassicicola AND Phoma lingam LEAF SPOT DISEASES ON CANOLA PLANTS UNDER GREENHOUSE CONDITIONS

Document Type : Original Article

Authors

1 Expert Sector at Ministry of Justice, Egypt

2 Plant Pathol. Dept., Fac. Agric., Zagazig Univ., Egypt

3 Plant Pathol. Res. Inst., Ismaillia Agric. Res. Station, ARC

Abstract

Black leaf spot and blackleg diseases of canola were studied during three successive growing  seasons (2010 /2011, 2011/2012 and 2012/2013) in four Governorates (Giza, Ismaillia, Gharbia and Sharkia). The causal organisms were isolated from infected leaf samples, identified as Alternaria brassicicola (Sch.) Wiltshire and Phoma lingam (Tode) Desm and inspected for their pathogenic potentiality. Pactol was the most resistant canola cultivar while, Serw 4 was very susceptible one. Radish (Raphanus sativus L.) was highly susceptible host to be infect with the tested fungal genera compared with the other tested ones. Level of N1P1K1 fertilizer reduced disease incidence and severity. All tested bioagents reduced disease severity using attached leaf technique two days after inoculation. Trichoderma harzianum Rifai was the most effective in reducing severity of alternaria black spot disease. While T. viride Pers.reduced severity of blackleg disease. On the other hand, Bacillus subtilis reduced canola leaf spot disease caused by A. brassicicola and P. lingam. The tested fungicides reduced severity of canola disease using attached leaf. The disease severity caused by A. brassicicola was significantly reduced by Carbendazim. While, opposite results were obtained with P. lingam. The highest significant reduction percent was obviously noted when the higher Ridomil-Mancozeb concentration, was sprayed. On the other hand, Carbendazium was found to be the less effective fungicide in controlling P. lingam when the infected attached leaves examined under greenhouse conditions.

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