SURVEY AND IDENTIFICATION OF MAJOR FUNGI CAUSING ROOT ROT ON DATE PALM AND THEIR RELATIVE IMPORTANCE IN EGYPT

Résumé du livre

Date palms under the Egyptian conditions are subjected to infection with different diseases caused by many soil-borne pathogenic fungi which may cause considerable losses in the offshoots and trees. A survey was carried out during four years 2005-2008 in seven governorates. Aswan governorate showed the highest disease severity (45.00%), followed by Luxor (37.50%), Behaera (30.50%), Marsa-Matrouh (25.00%), Ismailia (5.00%), Sharkyia (3.75%) and Giza (2.50%). Isolation and identification of associated fungi showed that the most frequent fungi were Fusarium spp. and Thielaviopsis paradoxa, while the least frequent were Botrydiplodia theomromae and Rhizctonia solani. The most virulent fungi were F. oxysporum, F. moniliforme, F. solani and T. paradoxa which were responsible for the root rot incidence that started with gradual yellowing that reached the palm tip followed by quick death. All the tested cultivars were susceptible to infection by the isolated pathogenic fungi. Hayany cultivar was the most susceptible to infection, followed by Sammany cultivar. While Zaghloul cultivar was the least susceptible.