چکیده پوسیدگی عمومی طوقه و ریشه گندم در سال های اخیر به عنوان یک بیماری مهم در استان خراسان شمالی جلب توجه نموده است. به منظور شناسایی عامل یا عوامل اصلی قارچی بیماری در سال های زراعی 86- 1385و87 - 1386 نمونه برداری هائی از مزارع گندم آبی مشکوک به بیماری درمناطق شیروان، فاروج، بجنورد، اسفراین و مانه و سملقان در سه مرحله گیاهچه، پنجه زنی تا ساقه رفتن و ظهور سنبله تا سفت شدن دانه به عمل آمد. از ب...

black stem is one of the most important fungal diseases of sunflower which is caused by phoma macdonaldii. this research was conducted to clarify the interactions between a few breeder lines and wild-type accessions of sunflower with seven isolates of phoma macdonaldii, the causal agent, under controlled conditions. the experiment was carried out in randomized complete block design with three r...

Phoma black stem and leaf spot disease (Phoma medicaginis) not only destroys annual Medicago spp. forage seed yield but also reduces herbage quality by consequent phytoestrogen production that ovulation of grazing animals. Two controlled environment studies evaluated the effects plant developmental stage in rugosa ‘Paraponto’ M. scutellata ‘Sava’ different inoculum concentrations P. medicaginis...

Previously, flaviolin was isolated from the blackish culture solution of Phoma wasabiae [1]. In continuation of the study on the metabolites of this mold, we have now isolated 2-hydroxy-6-methoxy-3,5-dimethyl-l,4-benzoquinone. This benzoquinone was already synthesized [2], but has not been found as a natural product. In this paper we wish to report on the isolation of the above quinone from the...