Erkol Demirci

Identification and pathogenicity ofRhizoctonia solani and binucleateRhizoctonia anastomosis groups isolated from forage legumes in Erzurum, Turkey

AbstrastThree-hundred-twenty-five isolates ofRhizoctonia (215R. solani and 110 binucleateRhizoctonia) were obtained from roots and crowns of alfalfa, sainfoin and common vetch grown in Erzurum, Turkey. The isolates were assigned to five anastomosis groups (AG) ofR. solani (AG-2-1, AG-3, AG-4, AG-5, and AG-10) and two anastomosis groups of binucleateRhizoctonia (AG-I and AG-K). In pathogenicity tests on alfalfa, sainfoin and common vetch, the highest disease severities were caused by isolates of AG-4 and AG-5. Isolates of AG-10 and AG-I were not pathogenic on the three tested forage legumes, whereas isolates of AG-K on alfalfa and sainfoin, and of AG-2-1 on sainfoin, were moderately virulent. Alfalfa isolate AG-3 was moderately virulent on sainfoin. This is the first report ofR. solani AG-3, AG-5, AG-10 and binucleateRhizoctonia AG-I on alfalfa. In addition, all theR. solani and binucleateRhizoctonia groups isolated from sainfoin and common vetch were recovered from these crops for the first time in Turkey.

Identification and pathogenicity ofFusarium spp. from stem bases of winter wheat in Erzurum, Turkey

Four-hundred-sixty-eightFusarium andFusarium-like isolates were obtained from crowns and subcrown internodes of winter wheat grown in Erzurum, Turkey. Of these isolates, 34.8% wereFusarium acuminatum, 32.3% wereF. equiseti, 16.9% wereF. oxysporum, 15.0% wereMicrodochium nivale (formerlyFusarium nivale), 0.6% wereF. tabacinum and 0.4% wereF. solani. In pathogenicity tests on wheat, the highest disease severity was caused by isolates ofM. nivale, whereas isolates ofF. acuminatum, F. equiseti, F. oxysporum andF. solani were slightly virulent; isolates ofF. tabacinum were nonpathogenic. This is the first report ofM. nivale andF. tabacinum from wheat in Turkey.

Species of Fusarium on sainfoin in Erzurum, Turkey.

Abstract One hundred and eleven Fusarium isolates were obtained from crowns and roots of sainfoin plants (Onobrychis viciifolia) affected by crown and root rot, grown in Erzurum (Turkey) during 1998 and 1999. Fusarium acuminatum (55% of isolates determined), F. solani (17%), F. oxysporum (14%), F. avenaceum (8%), F. equiseti (4%), and F. proliferatum (2%) were identified. Among these, F. acuminatum, F. avenaceum, F. oxysporum, and F. solani were pathogenic to sainfoin. These are the first records of these fungi on sainfoin in Turkey.

Colletotrichum Türleri ile Yabancı Otların Biyolojik Kontrolü / Biological Control of Weeds with Colletotrichum Species

OZET: Yabanci otlarla mucadelede kimyasal ilac (herbisit) kullanmanin insan sagligini olumsuz etkilemesi, cevreyi kirletmesi, kullanilan ilaclara bagisiklik kazanilmasi ve dogal dengenin bozulmasi gibi baslica sorunlarindan dolayi son yillarda biyolojik mucadelenin onemi gittikce artmistir. Yabanci otlarin biyolojik mucadelesinde kullanilan fungal bitki patojenli formulasyonlara mikoherbisit adi verilmektedir. Bu yayinda, yabanci otlarin biyolojik kontrolunde mikoherbisit olarak kullanilan veya mikoherbisit olarak kullanilma calismalari devam eden Colletotrichum turleri hakkinda bilgiler verilmistir. Anahtar Kelimeler: yabanci ot, Colletotrichum, mikoherbisit Biological Control of Weeds with Colletotrichum Species ABSTRACT: The importance of biological control of weeds has been gradually increased in latest years because of the using chemicals for control of weeds has negative effects for human healty, led to enviromental contamination and disturb natural environment. The fungal formulation using biological control of weeds named as mycoherbicide. In this paper, the information concerning Colletotrichum species used as mycoherbicide or having potential for biological control of weeds was given Key Words: weed, Colletotrichum, mycoherbicide