نشریه پژوهش های کاربردی در گیاه پزشکی
سال هشتم شماره 1 (بهار 1398)

Over the past two decades, there has been an increasing interest in the study of endophytes, their origin, biodiversity, the interactions between endophytes and host plants, the role of endophytes in ecology, as well as the chemical properties and biological activity of secondary metabolites produced by them. In this research endophytic fungi from twigs and branches of oak in Hatam-baig and Kalibar regions were identified based on molecular and morphological characteristics. Towards this aim, samples were collected from twigs and branches of oak trees in above-mentioned regions during June and September 2014. Pure cultures were established using a single spore or hyphal tip techniques. The identity of fungal isolates was determined based on morphological characteristics and sequence data from ITS-rDNA and Tub region. In this study 25 fungal species including Alternaria alternata species complex, Arthrinium arundinis, Aspergillus flavus, Bipolaris spicifera, Biscogniauxia mediterranea, Chaetomium globosum, Clonostachys rosea, Cladosporium cladosporioides, Daldinia vernicosa, Daldinia palmensis, Daldinia loculata, Discula quercina, Epicoccum nigrum, Fusarium oxysporum, Fusarium proliferatum, Fusarium solani, Nigrospora oryzae, Ochrocladosporium elatum, Paecilomyces formosus, Penicillium commune, Penicillium spinulosum, Pyronema domesticum, Sordaria fimicola, Sordaria sibutii and Trichothecium roseum were identified as endophytic fungi inhabiting twigs and branches of oak trees in Hatam-baig and Kalibar region. The majority of the species that were identified in this study, are reported for the first time from Quercus macranthera. The assemblage of endophytic fungi in healthy tissues of oak trees might indicate that some of the fungi as possible latent pathogens of oak.

Pistachio (Pistacia vera L.) is one of the most important, valuable and strategic horticultural productions in Iran. The common pistachio psyllid, Agonoscena pistaciae Burckardt and Lauterer (Hemiptera: Aphalaridae), is  the most important pest Iran's in pistachio orchards. The damage of this pest to pistachio product is economic, every year, therefore it is necessary to control the pest with chemical pesticides. In this study, the effects of some insecticides from different classes including spirotetramate (Monvento®, SC 10%), spiromesifen (Oberon®, SC 240), dinotefuran (Starkle®, SG 20%), chlorfluazuron (Atabron®, EC 5%), thiametoxam + lambda cyhalothrin (Eforia®, SC 247), phenoxycarb + lufenuron (Lufox®, EC 105) and hexaflumurom (Consult®, EC 10%) was investigated on the reduction of population density of eggs and nymphs of common pistachio psyllid Experiments were conducted as randomized complete block design with four replicates under field conditions. The sampling was done 3, 7, 14, 21 and 28 days after treatment. The highest and lowest percent  reduction of egg population  were observed in spirotetramate treatment (99.27%) at 21 days after-treatment and phenoxycarb + lufenuron (0%) and chlorfluzuron treatment (0%) at 3 and 28 days after-treatment, respectively. The highest and lowest percent reduction of nymphs were recorded at spirotetramate treatment (99.54%) at 28 days after-treatment and dinotefuran treatment (0%) at 7 days after treatment, respectively. The results of this study showed that using of spirotetramate due to its different mode of action and environment friendly insecticides such as hexaflumurom, chlorfluazuron and phenoxycarb + lufenuron could be acceptable,  in the integrated management of A. pistaciae.

This investigation was conducted in afforestation around Karaj in order to determine flora and spatial distribution patterns description and weed density in 2012. The studied region was divided into 50×50 meters grids, then weeds were identified, counted and recorded in a 1×1 quadrates. Fiftysix weed species belonging to 18 families were identified: Four species with average numbers of more than 5 plants/m2 Consisting Avena fatua, Hordeum murinum, Chondrilla juncea and Aegilops ovate with 19.566, 18.080, 6.190 and 5.677 plants/m2 were dominant species. Asteraceae, Poaceae, Fabaceae, Apiaceae and Lamiaceae families with 13, 10, 6, 5, and 4 species have maximum species number of weeds. Weed infestation maps generated by geostatistics showed that the dominant species formed infestation spots with the oradius of more than 50 m diameter. The result of experiment about diversity indexes showed that studied region had high variety as diversity indexes. The results of this study can be useful to improve decision making and efficient control of weeds.

Phoridae is considered as one of the largest families of order Diptera. This family includes about 4,000 known species in more than 260 genera belongs to four subfamilies. Faunistic study on phorid flies of the genus Megaselia Rondani 1856 (Diptera: Phoridae), was conducted on different grasslands and forests of East Azerbaijan province during 2009-2018. Specimens were collected using sweeping net on various plants and Malaise trap. Totally 14 species Megaselia albicaudata (Wood, 1910), *M. albocingulata (Strobl, 1906), *M. angustiata Schmitz, 1936, *M. bovista (Gimmerthal, 1848), *M. brevior (Schmitz, 1924), *M. curvicapilla Schmitz, 1947, *M. longiseta (Wood, 1909), *M. oxybelorum Schmitz, 1928, *M. posticata (Strobl, 1898), M. rufipes (Meigen, 1804), *M. stichata (Lundbeck, 1920), *M. styloprocta (Schmitz, 1921), *M. tama (Schmitz, 1926) and M. xanthozona (Strobl, 1892) belonging to this genus have been identified. Among the identified species 11 species which are marked with an asterisk (*), are recognized to be new for the Iranian fauna. Moreover, an identification key, geographical distribution and supplementary figures of the studied species are presented.

Chemical control using fungicides is considered as the most important method to control Botrytis cinerea in different crops. However, effective management of this pathogen requires information on presence and frequency of fungicide-resistant strains and levels of resistance as well as mutations associated with the resistance. In this research, sensitivity of 103 B. cinerea isolates collected from vineyards in different regions of West Azarbaijan province was assessed to carbendazim (60 WP) and azoxystrobin (25 SC). Among the studied isolates, 39 (38%) and 35 (34%) isolates were highly resistant to carbendazim and azoxystrobin, respectively. Partial sequencing of the beta tubulin gene indicated that in carbendazim-resistant strains GAG had changed to GCG which led to the substitution of glutamic acid by alanine at the codon position 198 and subsequently appearance of Ben R1 phenotype. Analysis of the partial cyt b gene sequence revealed that in azoxystrobin-resistant strains GGT had changed to GCT (point mutation) leading to substitution of glycine by alanine at the codon position 143. Further, one of the azoxystrobin-sensitive isolates had Bcbi-143/144 intron immediately after codon 143 in cyt b. The results indicated that application of benzimidazole and strobilurin fungicides groups are not recommended for B. cinerea management in the vineyards of the region. However, given that benzimidazole-resistant strains had Ben R1 phenotype, benzimidazole fungicides can be used with diethofencarb or zoxamide as a mixture partner to effectively control both sensitive and resistant strains.

     Most natural enemies have low maintenance capabilities so they are often cultivated shortly before release. In the case of parasitoids, their hosts can be stored instead of parasitoids. Since storage of host eggs can increase the efficiency of the mass production units of Trichogramma wasps, this approach has been suggested by various researchers as a suitable method for mass production of Trichogramma species. As regards that there are few studies on the effect of low temperatures on the growth population parameters of parasitoid, so in this study the effect of cold storage of Phthorimaea operculella (Zeller) eggs at 4°C for 0, 1, 4, 7, 15 and 30 days on biological and population parameters of Trichogramma brassicae Bezdenko were investigated. This experiment was conducted in a completely randomized design with 25 replications. Mean comparisons were performed using Duncan's test. The results showed that developmental time, longevity, parasitism rate, percentage of emergence, fecundity and oviposition period of T. brassicae were significantly different between treatments and the all parameters decreased when the storage period increased. It was also determined that all population growth parameters had a significant difference between the control and cold treatments. Due to the parasitism and adult emergency rate, longevity and fecundity of T. brassicae on stored host, eggs of P. operculella can be stored at 4°C for up to two weeks without significant negative effect on the efficiency of the T. brassicae. However, based on population growth parameters, maintenance of host eggs for up to one week are most recommended.

Fusarium culmorum and F. graminearum are causal agents of the important disease of cereals that lead to extensive yield and quality loss of wheat. Due to the hazardous effect of chemical compounds, alternative method to control these pathogens in the field is necessary. In this study, the effects of methanolic extract of Thymus vulgaris, Peganum harmala,Cuminum cyminum and Stachys lavandulifolia on mycelial growth of these  species was studied in laboratory and green house conditions. The antimicrobial activity of these pathogens was determined through poison food assay at 250, 500, 750 and 1000 ppm concentrations. Among all methanolic extracts, T. vulgaris extract at concentration of 1000 ppm was potentially effective against F. culmorum by 81.25%. Also, methanolic extracts of P. harmala at concentration of 1000 ppm showed high antifungal activity against F. graminearum by 82.33%. Thymus vulgaris extract had the lowest MIC value (1 mg/ml) and MFC value (2 mg/ml) for F. culmorum. Also, Peganum harmala extract had the lowest MIC value (0.78 mg/ml) and MFC value (1.56 mg/ml) for F. graminearum. Methanolic extract of T. vulgaris and P. harmala were effective in incrising wet and dry weight of roots and shoots in greenhouse condition, too.