دراسة مختبرية لتقويم فاعلية عزلات مختلفة من أنواع فطور الترايكوديرما تجاه بعض الفطور الممرضة المنقولة بالتربة

Abstract EN

Trichoderma isolates were assessed for their ability to inhibit soil-borne pathogenic fungi in vitro on PDA medium at 23 ± 2 C during the period from 1994 to 1997.

The averages of inhibitory coefficients (i.

c.) of Trichoderma isolates against Verticillium dahliae Kleb., Fusarium oxysporum f.

sp.

lycopersici (Sacc.) Snyder et Hansen., Rosellinia necatrix Berlese.

and Rhizoctonia solani Kühn.

were 79.7, 76.9, 76.1 and 70.2%, respectively.

Trichoderma isolates efficacies were moderate against Sclerotium cepivorum Berk.

and Cylindrocarpon sp., their i.

c.

were 63.1 and 60.4%, respectively.

Trichoderma isolates against F.

oxysporum f.

sp.

dianthii (Prill.

Et Delacr.) Snyder et Hansen.

had the lowest efficacy (43.7%).

The highest inhibition on radial colony growth (r.

c.

g.) of R.

solani, R.

necatrix, V.

dahliae and S.

cepivorum was noted with application of some isolates of Trichoderma koningii Oudem., their i.

c.

against V.

dahliae was similar to that of Glioclladium virens Miller, Giddens, Foster & Arx.

isolate.

The G.

virens isolate gave most inhibitory effect on r.

c.

g.

of F.

oxysporum f.

sp.

lycopersici.

T.

hamatum (Bonord) Bainier.

isolates were most efficient in suppressing the r.

c.

g.

of Cylindrocarpon sp.

and F.

oxysporum f.

sp.

dianthii.

Many Trichoderma isolates completely colonized the mycelium of some pathogenic fungi.