EFFECT OF SOLAR HEATING, CHEMICAL DISINFESTANTS AND SOME BIOLOGICAL AGENTS ON LETTUCE FUSARIUM WILT CONTROL YIELD AND QUALITY

Abstract

Isolation trials from lettuce plant with wilt symptoms collected from Giza, Qalubiya and Behera Governorates yielded Fusarium oxysporum Schlecht, Macrophomina phaseolina (Tassi) Goid and Mucor sp. Fresen. The isolates of the fungus F. oxysporum were exposed to pathogenicity test by using lettuce (cv. Aviram) seedlings. The all isolates infected the lettuce seedlings with different levels. Giza isolate as the most virulent morphologically and molecularly characterized as F. oxysporum. Also, it was failing to infect non-host plants in the host range test. Temperature degrees, relative humidity levels and root exudates of lettuce seedlings significantly influenced the growth and sporulation of the tested fungus on PDA medium.