Crude extracts from the shoots of oat cv. Quoll were tested against four species of bacteria and eight species of fungi. Bacterial growth was not inhibited. The mycelia growth of all Pyrenophora species tested, except Pyrenophora avenae DAR 33699, was inhibited by the crude extract, whereas the mycelia growth of Fusarium graminearum, Mycosphaerella pinodes and Rhizoctonia solani was not affected. Partially purified fractions with high concentrations of flavone-C-glycosides had no inhibitory effect against P. teres f. sp. teres and P. teres f. sp. maculata. The saponin 26-desglucoavenacoside B accounted for most of the activity against P. teres f. sp. teres with a minor contribution from the other saponins, 26-desglucoavenacoside A and avenacosides A and B.

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Crude aqueous and methanolic extracts of 63 plant species belonging to 23 families collected from the west of Iran were screened for antifungal activity against three economically important phytopathogenic fungi, Cochliobolus sativus, Fusarium oxysporum and Rhizoctonia solani. Bioassay of extract was conducted by paper disc diffusion method on agar plate cultures with four replications. 21 of the 63 (33%) plant species showed inhibitory activity against at least one of the fungi. 16 (25%), 10 (16%) and 16 (25%) tested plant species inhibited the mycelial growth of R. solani, F. oxysporum and C. sativus, respectively. Centaurea behen, Lavandula sp., roots of Tribulus terrestris were the most active plant species against R. solani, F. oxysporum, and C. sativus, respectively. Extracts of Glycyrrhiza glabra, Rosmarinus officinalis, Avena sativa, Vaccaria pyramidata, Centaurea behen, Anagalis arvensis and T. terrestris exhibited a broad-spectrum of antifungal activity. According to these results, we conclude that the flora in the west of Iran can be regarded as a rich source of plants with antifungal activity. Therefore, further screening of other plant species, identifying active fractions or metabolites and in vivo application of active extracts are warranted.

Stevia rebaudiana Bertoni is one of two species that contains steviol glycosides. Among steviol glycosides that extracted from leaves, stevioside and rebaudioside A are the two major and the sweetest glycosides that are about 200-300 times sweeter than sucrose with zero calories. The best method for stevia propagation is tissue culture. So, for investigation of nutrients in medium, we studied the effect of different concentrations of MS media (MS, 0.5 MS, 0.25 MS, 0 MS) on morphological traits, UGT74G1 and UGT76G1 genes expression and accumulation of steviol glycosides in stevia leaves. The best growth rate (0.472 mm/d) has occurred in plants grown in MS media. Also, the highest gene expression of UGT74G1 gene (1.000 Total lab unit) was seen under MS treatment. However, the highest expression level of UGT76G1 gene (1.701 Total lab unit) was observed at plants grown in 0 MS. The highest amount of both Stevioside and Rebaudioside A (14.23 and 8.12, respectively) were accumulated in plants under MS treatment. Obviously, dilution of MS media associated with decreasing in both expression of the intended genes and accumulation of steviol glycosides.

Genetic variation among 78 irrigated bread wheat genotypes was studied for their nutritional value and baking quality traits as well as some agronomic traits. The experiment was conducted in a randomized complete block design with three replicates under normal and terminal drought stress conditions in Kermanshah, Iran during 2012-2013 cropping season. The results of combined ANOVA indicated highly significant genotypic differences for all traits. All studied traits except grain yield, hectoliter weight and grain fiber content were significantly affected by genotype × environment interaction. Drought stress reduced grain yield, thousand kernel weight, gluten index, grain starch content and hectoliter weight and slightly promoted grain protein and fiber contents, falling number, total gluten and ratio of wet gluten to grain protein content. Grain yield by 31.66% and falling number by 9.20% attained the highest decrease and increase due to drought stress. There were negative and significant correlations among grain yield with grain protein and fiber contents under both conditions. Results of cluster analysis showed that newer genotypes had more grain yield and gluten index than older ones, but instead, they had the lower grain protein and fiber contents. It is thought that wheat breeders have bred cultivars with high grain yield, low protein content, and improved bread-making attributes during last seven decades. While older genotypes indicated significantly higher protein contents, and some of them had higher gluten index. We concluded from this study that it is imperative for breeders to pay more attention to improve qualitative traits coordinated to grain yield.