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1.
Trunk disease is a major problem on grapevine in Zanjan province, causing serious decline, despite which its aetiology remains unknown. The purpose of this study was to investigate factors involved in grapevine decline in vineyards of Zanjan province. Samples were collected from twigs and branches of grapevines in the region between October and November 2018. Fungal isolates were identified based on morphological characteristics and ITS-rDNA sequence data for selected isolates. The frequency and diversity of the fungal community recovered from grapevines in Darreh Sejin in Zanjan province were higher than in other regions. A total of 112 fungal isolates comprising 22 species were recovered. Phaeoacremonium minimum, Microsphaeropsis olivacea and Kalmusia variispora were identified as the dominant species in the region examined and could be considered the main trunk pathogens of grapevines in Zanjan region. In inoculation tests, M. olivacea was proved to be pathogenic on grapevine for the first time in this study.  相似文献   
2.
Developing a fast and reliable soil testing method is critical for improving soil testing efficiency and ensuring reliable fertilizer recommendation. The objectives of this study were to evaluate sodium ethylene diamine tetra acetic acid (Na2-EDTA) as a replacement for ammonium bicarbonate-diethylenetriaminepentaacetic acid (AB-DTPA) to extract phosphorus (P) to determinate the relationships between extractable P and its uptake by crop in calcareous soils. Na2-EDTA and AB-DTPA was compared by the amounts of extracted P by analyzing soil samples collected from agricultural production areas. There were significant correlations between Na2-EDTA and AB-DTPA for soil test P based on soils collected from the agricultural field. Soil test P by both extractants was significantly correlated with plant P concentration. Na2-EDTA was identified as an alternate improved extraction method instead of AB-DTPA in calcareous soils based on this study. However, more work will be needed to identify the correlation of the two extractants and crop responses under a field condition.  相似文献   
3.
Understanding farmers’ decision process on the adoption of biological control (BC) may help in promoting adoption. This study explored for the first time the impact of marketing mix elements (product, price, promotion, and place) on bolstering BC for the management of rice stem borer (Chilo suppressalis Walker) among rice farmers in Fuman County in northern Iran. Farmers using BC were familiar with this method primarily via village councils and rural municipality organizations (Dehyaris) and then via distributors of trichocards. Almost half of the farmers (48.3%) had weak to moderate level of contact with distributors of trichocards. All four elements (4Ps) of marketing mix (product, place, price, and promotion) were effective on the marketing of BC agents. Place (distribution) mix, followed by price mix, were the most important factors in marketing trichocards in farmers’ views. According to the sensitivity to 4Ps of marketing mix, most farmers were grouped as semi-sensitive (45.6%) and sensitive (39.4%). Overall, the availability of biological agent products in the market, the affordable price of the products, and the strong relationship of rural people with village councils and rural municipality organizations (Dehyaris) are crucial factors for BC promotion in paddy fields of Fuman.  相似文献   
4.
Blackleg, caused by a complex of Leptosphaeria species (L. maculans and L. biglobosa), is a fungal disease on Brassica species, especially important in canola (Brassica napus). Since the first report of L. biglobosa in Iran in 2007 and L. maculans in 2008, both species are now of major importance in Iran affecting 10 provinces and 30 regions, with a higher prevalence in the northern provinces of Mazandaran and Golestan. Despite the rapid progression of the disease and the emergence of new Leptosphaeria races in Iran, the research into this pathogen has not progressed at the same rate and is limited to phenotypic characterization studies, pathogenicity research, and to a lesser extent, disease management research. Given the rapid increase in canola cultivation in Iran and changes in the genetic diversity of the pathogen populations, it is likely that blackleg disease will increasingly become a severe threat to Iran’s canola production. Therefore, systematic and prospective studies, along with fundamental research on the pathogen's biology, epidemiology, and genetic diversity, would provide critical information for the development of disease management strategies. Here, we review the research that has been carried out to date on blackleg disease in Iran and describe the extent of progress towards disease control, especially in disease-prone regions.  相似文献   
5.
Paddy and Water Environment - Application of common leaching and flushing methods is often impractical due to freshwater scarcity, groundwater pollution and a lack of suitable drainage systems. To...  相似文献   
6.
In this study, chitosan and pentasodium tripolyphosphate (TPP)-based bilayers were fabricated on the cationized woven cotton fabrics via layer-by-layer (LBL) self-assembly technique. The initial cationic charges on cotton fabric were produced through the aminization procedure involving the covalent attachment of reactive dye to cotton fabric and subsequent reductive cleavage of the dye to free amine. Different numbers of bilayers (1, 5, and 10) consisting of chitosan/TPP have been deposited on the fabrics. The surface morphology, cationic group content, chemical surface modification, whiteness index, surface tension and antibacterial properties of the modified cotton samples were investigated using scanning electron microscopy (SEM), methylene blue test, FTIR, reflectance spectroscopy, water contact angle measurements and antibacterial test, respectively. The bacterial inhibition experiments demonstrated that the modified cotton fabric with the addition of chitosan/TPP bilayers can increase the degree of inhibition on E. coli and S. aureus bacteria. The utilized LBL method was an easy and cost-effective procedure for developing of novel antibacterial textiles with the highly attractive feature in the medical and hygienic products.  相似文献   
7.
A diatrypaceous fungus was isolated consistently from cankers on Populus nigra trees showing dieback symptoms in Kohgiluyeh Boyer‐Ahmad, Zanjan and Esfahan provinces in Iran. Morphological characteristics and phylogenetic analyses of the ITS region of the rDNA identified the taxon as Cryptosphaeria pullmanensis. Pathogenicity tests conducted in potted 3‐month‐old cuttings of P. nigra confirmed Koch's postulates and revealed that C. pullmanensis caused canker on this host. This is the first report of C. pullmanensis causing a canker disease on P. nigra in Iran.  相似文献   
8.
The objective of this study was to synthesize and characterize two novel four-arm star-shaped copolymers of N-isopropylacrylamide (NIPAAm), methacrylic acid (MAA), N,N-(dimethylamino) ethyl methacrylate (DMAEMA) and 1-vinyl-2-pyrrolidone (VP) that was initiated from a new tetramethacrylate monomer (TMAM) as the core by the free radical polymerization approach. Novel multiacrylic monomer was synthesized via three key consecutive reactions. All the intermediates and the final product have been fully characterized. The polymerization reaction was conducted by the core first method and the star-shaped copolymers were analyzed by FT-IR, 1H NMR and Thermo-Gravimetric Analysis (TGA). MTT assay was used to evaluate in vitro cytotoxicity of the star copolymers on lung cancer cell lines. These star copolymers showed no in vitro cytotoxicity to A549 cells. The results showed that these copolymers can be promising drug carriers because they showed no in vitro cytotoxicity and they have various functional groups for association and interaction with drugs.  相似文献   
9.
We investigated wood anatomical changes due to uptake and accumulation of cadmium and lead from contaminated soils in Acer velutinum Boiss seedlings. Two-year old seedlings were exposed for 180 days to soil concentrations with varying cadmium and lead concentrations. We measured three wood anatomical traits, average vessel area(μm2), vessel number per square millimetre, and vessel lumen area percentage (%). For assessing the cadmium and lead accumulation, we measured the concentrations in the soil, leaf, stem, and root. Average vessel area and vessel lumen area percentage were similar (p>0.05) incontrol and treated seedlings. Vessel number per square millimetre showed a decreasing trend from pith to bark in control and treated seedlings, and the trend was more pronounced in treated seedlings. We conclude that vessel number per square millimetre in A. velutinum is influenced by soil contamination. A. velutinum Boiss is not a suitable species for remediation of soils contaminated by cadmium and lead but it can beused as an indicator of the soil lead contamination, because lead concentrations in seedlings increased with increasing amount of lead in the soil.  相似文献   
10.
The genetic structure of 276 Sclerotinia sclerotiorum isolates representing 37 field populations from four provinces in northern Iran were analysed with six polymorphic microsatellite loci. In total, 80 haplotypes were detected with 19 haplotypes (23.7%) shared amongst at least two regional populations. None of the haplotypes were shared among all four regional populations. Of the 80 haplotypes, 32 haplotypes (40%) occurred in low frequencies represented by only one isolate. Moderate levels of gene diversity (H = 0.51 to 0.61) and genotypic diversity (Ĝ = 12.0 to 22.0; clonal fraction = 0.39 to 0.67) for regional populations were observed. Genotypic diversities (Ĝ) did not differ significantly among populations. All regional populations were in linkage equilibrium indicating the occurrence of outcrossing. Low to moderate levels of population subdivision (0.03 to 0.07), were observed among regional populations. Only one large panmictic population was inferred by Structure, indicating no significant population structure. A Mantel test showed no significant isolation by distance (r = −0.43; P = 0.18), indicating anthropogenic movement of inoculum. The results demonstrated that S. sclerotiorum populations in northern Iran, are randomly mating and have a number of shared haplotypes among regional populations; this possibly represents recent founder populations and/or a high occurrence of anthropogenic migration of infected plant material among populations.  相似文献   
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