اختبار القدرة الإمراضية لعزلات من الفطر Fusarium oxysporum f. sp. Lycopersici على نبات البندورة، و تأثير بعض المبيدات الخطي للعزلات المختبرة في الظروف المخبرية

الملخص EN

The pathogenicity of three isolates of F.

oxysporum f.

sp.

lycopersici has been tested on tomato plants.

The results showed that the isolates differed in their pathogenicity as following: the first isolate was the most virulent, as the severity of the infection ranged from 86.7 to 100% on the leaves, and from 93.3 to 100% on the roots; the second was intermediate in its virulence (80 – 100 % on leaves, and 93.3 – 100 % on roots); while the third isolate was the least virulent with values of (66.7 – 86.7 % on leaves, and 73.3 – 93.3 % on roots).

Tomato varieties differed also in their susceptibility to infection by the tested isolates.

Although all isolates were highly susceptible to infection, the two varieties "Tala and Lamntine" were the most susceptible to Fusarium wilt, Dora was the least susceptible one, while.

Alegro and Super red were intermediate The results showed that there was a difference in the effectiveness of the tested fungicides: Toloclofos-methyl had the lowest effect on fungal growth, while Carbendazim was the most effective fungicide in inhibiting the isolates growth followed by Thiophanate-methyl.

ED50 values of fungal isolates revealed that isolates differed in their sensitivity to fungicides: Isolate 3 was the most sensitive, followed by isolate 2, while isolate 1 was the most resistant.