Anatomical changes associated with mango seedlings root rot
Abstract: Abstract:
Seven fungal genera were isolated from diseased mango seedlings originated from seed grown in different nurseries located in three Egyptian governorates during seasons of 2010 and 2011. The fungus Botryodiplodia theobromae Pat. was the most frequently isolated fungi followed by Rhizoctonia solani Kühn. and Fusarium solani (Mart) Sacc. while Pestalotiopsis sp. was the lowest frequent one. The most pathogenic fungus was B. theobromae compared to Pestalatiopsis sp., which caused the lowest percentage of root rot infection. Anantomical changes studies of transverse and longitudinal root sections, using light microscope after 30 days from artificial infection, revealed that the cortex layer was completely colonized by B. theobromae, F. solani compared with R. solani, which attack and colonized firstly the lateral and hairy roots. This colonization was associated with disorganized epidermal and cortical cells in addition to a dark brown color consisting of crushed and necrotic cells and tissues. Such disorders were not observed in un-inoculated mango seedling. Forty five days after artificial inoculation with B. theobromae or F. solani the fungal hyphae were clearly noticed in both xylem vessels and xylem parenchyma causing necrosis and deposition of dark material like gum as well as abundant production of tylosis. There were correlation between histological changes and disease development, at the time of inoculation, the foliar appeared vigorously green colored and erect. The inoculated seedling after 30 day was paler, less vigorous, and less rigid than those of non-inoculated ones. In the end of experimental after 45 days, seedlings became yellow, wilting and finally the seedlings were dead and turned brown.

Key wards: Anatomical changes, Soil borne fungi, mango, root-rot diseases, Botryodiplodia theobromae, Rhizoctonia solani, Fusarium solani.
Publication year 2013
Pages 185-195
Organization Name
Author(s) from ARC
AGROVOC
TERMS		 Mangoes.
Publication Type Researsh & Applied Activities
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