‫بثغ عجيؼي‬ٜٗ ٝ ‫ـقي‬ٝ‫ليي ؼـ ًٍب‬ٞٓٞ‫شفّ ثي‬ًٜ ‫٘بيً ٗٔي‬١ ٚ‫ٗي‬ٞ‫و‬ 1394 ‫ ثڇٽٿ‬14 ‫ ڂ‬13 Fusarium ‫قاي‬ٚ‫ًىي‬ٞ‫ ؿيفس‬ٝ ‫قا‬ٚ‫ًىي‬ٞ‫بي س‬١٠‫شفّ خؽاي‬ًٜٞ‫ ػبْٗ ثي‬ٙ‫ا‬ٜٞ‫ػ‬٠‫ ث‬Trichoderma harzianum ‫سبثيف‬ ٠ٔ‫ج‬ٜ‫ٗي و‬ٞ‫قاـي‬ٞ‫ ػبْٗ ثي٘بـي ثاليز ك‬graminearum ‫في‬١‫ دفيىب عب‬ٝ ‫ي٘ب غبٓؽي‬ٛ ‫فؼڂوڋ ټٍڇؽ‬٨ ‫ ؼاڀٍٵبڄ‬،‫ ؼاڀٍٱؽڄ ٍٰبڂـقڊ‬،‫ٴفڂڄ ٴڍبڄدكٌٱڋ‬ khaledi.nima@stu.um.ac.ir :‫ڀڃڌىځؽڄ ټىئڃٶ‬ ‫ ثڃڌمڄ‬Fusarium ‫ڋ اق خځه‬٩‫الر ؼاڀڅـڌك ؼـ ؼڀڍب اوز ٰڅ سڃوٗ ٴڃڀڅچبڊ ټػشٹ‬٤ ‫ڃقاـڌڃټڋ وځجٹڅ ڌٱڋ اق ټڇٻسفڌٿ ثڍٽبـڊچبڊ‬٨ ‫ثالڌز‬ ‫جڍٷ ؼاٰىڋ ڀڍڃاٸځڃٶ ڂ ڀڍڃاٸځڃٶ ـا سڃٸڍؽ ټڋٰځؽ‬٬ ‫څاڊ اق سفڌٱڃسىڍٿچب اق‬٠‫بـذ ټدٽڃ‬٬ ‫ اڌٿ‬.‫ اڌدبؼ ټڋٌڃؼ‬Fusarium graminearum ‫ٴڃڀڅ‬ ،BI( Trichoderma harzianum ‫بـذ‬٬ ‫ ؼـ اڌٿ دمڂچً اثفار آڀشبٴڃڀڍىشڋ دځح خؽاڌڅڊ‬.‫ٰڅ ثفاڊ والټشڋ اڀىبپ ڂ خبڀڃـاپ ټٕف اوز‬ ‫فاـ‬٬ ‫ سطز ٌفاڌٗ آقټبڌٍٵبچڋ ټڃـؼ ثفـوڋ‬F. graminearum ‫ڍف سڃٰىڍٿقاڊ‬٤ ‫ٹڍڅ زڇبـ خؽاڌڅ سڃٰىڍٿقا ڂ‬٠ )T5 ‫ ڂ‬T8 ،T14 ،T7 ‫فاـ ڂ‬٨ ‫ڍشڋ ڂ سأثڍف ټشبثڃٸڍزچبڊ‬٨‫بثز وبدفڂ‬٬‫ؽـر ـ‬٬ ‫ف‬ٝ‫ اق ڀ‬T. harzianum ‫ خؽاڌڅچبڊ‬،‫ ثفاڊ ثفـوڋ ټڍكاپ ٰځشفٶ ـٌؽ ټڍىٹڍڃټڋ‬.‫ز‬٨‫ٴف‬ ‫ ثڍٍشفڌٿ ؼـِؽ‬.‫شځؽ‬٨‫فاـٴف‬٬ ‫ڋ ثب زڇبـ سٱفاـ ټڃـؼ ثفـوڋ‬٨‫بٸت ٘فش ٰبټالً سّبؼ‬٬ ‫ ؼـ‬F. graminearum ‫ غبـج وٹڃٸڋ ثف ـڂڊ‬ٟ‫سفٌطبر ټبڌ‬ ‫ چٽسځڍٿ اق‬.‫ ثڃؼ‬%65/9 ‫ ثب‬T7 ‫ڍشڋ ټفثڃٖ ثڅ خؽاڌڅ‬٨‫بثز وبدفڂ‬٬‫ؽـر ـ‬٬ ‫ف‬ٝ‫) اق ڀ‬FH12 ‫ ڂ‬FH1( ‫ثبقؼاـڀؽٴڋ ؼـ ثڍٿ خؽاڌڅچبڊ سڃٰىڍٿقا‬ ‫ٹڍڅ‬٠ ‫ ؼاـاڊ ثڍٍشفڌٿ سبثڍف ثبقؼاـڀؽٴڋ‬89/5% ‫ ڂ‬%73/1 ‫ ثڅ سفسڍت ثب‬BI ‫ غبـج وٹڃٸڋ خؽاڌڅڊ‬ٟ‫فاـ ڂ سفٌطبر ټبڌ‬٨ ‫ف سأثڍف ټشبثڃٸڍزچبڊ‬ٝ‫ڀ‬ ‫بثز‬٬‫ؽـر ـ‬٬ ‫ف‬ٝ‫) اق ڀ‬FH27 ‫ ڂ‬FH11( ‫ڍفسڃٰىڍٿقا‬٤ ‫ٹڍڅ خؽاڌڅچبڊ‬٠ ‫ چٽسځڍٿ ثڍٍشفڌٿ ؼـِؽ ثبقؼاـڀؽٴڋ‬.‫خؽاڌڅچبڊ سڃٰىڍٿقا ثڃؼ‬ ‫ ثڅسفسڍت‬BI ‫ خؽاڌڅڊ‬،‫ غبـج وٹڃٸڋ‬ٟ‫فاـ ڂ سفٌطبر ټبڌ‬٨ ‫ف سأثڍف ټشبثڃٸڍزچبڊ‬ٝ‫ چٽسځڍٿ اق ڀ‬.‫ ثڃؼ‬%72/3 ‫ ثب‬BI ‫ڍشڋ ټفثڃٖ ثڅ خؽاڌڅ‬٨‫وبدفڂ‬ ‫ٹڍڅ‬٠ ‫ ثڍٍشفڌٿ ثبقؼاـڀؽٴڋ ـا‬BI ‫ خؽاڌڅ‬،‫ ثڅ٘ڃـ ٰٹڋ‬.‫ڍفسڃٰىڍٿقا ثڃؼ‬٤ ‫ٹڍڅ خؽاڌڅچبڊ‬٠ ‫ ؼاـاڊ ثڍٍشفڌٿ سبثڍف ثبقؼاـڀؽٴڋ‬91/6% ‫ ڂ‬%75/7 ‫ثب‬ ‫ځڋؼاـڊ ؼـ ټڍكاپ‬١‫ ټ‬٦‫ اغشال‬،‫ ؼاٌز ڂ ثفاوبن سدكڌڅ ڂ سطٹڍٷ آټبـڊ‬F. graminearum ‫ڍفسڃٰىڍٿقاڊ‬٤ ‫خؽاڌڅچبڊ سڃٰىڍٿقا ڂ‬ ‫فاـ‬٨‫ڍف‬٤ ‫ف ټڋـوؽ ٰڅ سفٌص سفٰڍجبر‬ٝ‫ ثڅ ڀ‬.‫ ؼـِؽ ټٍبچؽڄ ڀٍؽ‬5 ‫ص اضشٽبٶ‬ٙ‫ڍفسڃٰىڍٿقا ؼـ و‬٤ ‫ثبقؼاـڀؽٴڋ ـڂڊ خؽاڌڅچبڊ سڃٰىڍٿقا ڂ‬ .‫بـذ ثڍٽبـٴف ثبٌؽ‬٬ ‫ٹڍڅ اڌٿ‬٠ T. harzianum ‫ټڇٻسفڌٿ ټٱبڀڍىٻ آڀشبٴڃڀڍىشڋ‬ Fusarium graminearum ،Trichoderma harzianum ،‫ ٰځشفٶ ثڍڃٸڃلڌٯ‬:‫ًٔ٘بر ًٔيؽي‬ Effect of Trichoderma harzianum as biocontrol agent of toxigenic and non-toxigenic isolates of Fusarium graminearum causing wheat head blight disease Nima Khaledi and Parissa Taheri Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran Corresponding Author: khaledi.nima@stu.um.ac.ir Fusarium head blight (FHB) is one of the most important diseases of small grain cereal crops in the world, caused by several species of Fusarium, especially F. graminearum. This fungus produces a collection of trichothecenes such as deoxynivalenol and nivalenol that are harmful to human and animal health. In this research, antagonistic effects of 5 Trichoderma harzianum isolates (BI, T7, T14, T8 and T5) against 4 toxigenic and non-toxigenic isolates of Fusarium graminearum were investigated in vitro. In order to investigate the control effect of T. harzianum isolates on mycelial growth of the pathogen in vitro, the antagonistic isolates were evaluated for competitive saprophytic ability, inhibition effects of volatile metabolites and culture filtrates on F. graminearum in a completely randomized design with four replications. Maximum percentage of inhibition against toxigenic producing isolates (FH1 and FH12) based on competitive saprophytic ability belonged to the isolate T7 with 65.9%. Also, the isolate BI had the highest inhibitory effect of volatile metabolites and culture filtrates with 73.1% and 89.5%, respectively. Maximum percentage of inhibition against non-toxigenic producing isolates (FH11 and FH27) based on competitive saprophytic ability belonged to the isolate BI with 72.3%. Also, the isolate BI had the highest inhibitory effect of volatile metabolites and culture filtrates with 75.7% and 91.6%, respectively. In overall, the isolate BI had maximum inhibitory effect on toxigenic and nontoxigenic isolates of F. graminearum and statistical analysis revealed no significant differences in the rate of inhibition against toxigenic and non-toxigenic isolates in the 5% probability level. It seems that secretion of nonvolatile compounds is the most important antagonistic mechanism of T. harzianum against this pathogenic fungus. Keywords: Biological control, Trichoderma harzianum, Fusarium graminearum 85