جستجوی مقالات مرتبط با کلیدواژه « قارچ » در نشریات گروه « زراعت »

To evaluate the allelopathic and fungicidal effect of saffron leaf and corm aqueous extracts on the germination and growth characteristics of London rocket (Sisymbrium irio) and Fusarium solani, independent experiments were conducted as factorial arrangement based on the completely randomized design with four replications at the Faculty of Agriculture of Birjand University in 2022. Treatments to test the inhibitory effect of saffron extract on London rocket seed germination characteristics including two types of saffron organs (leaf and corm) and seven extract concentrations (0, 0.25, 0.5, 1, 1.5, 2, and 4 w/v %). Experimental treatments to investigate the inhibitory effect of saffron extract on the growth of Fusarium solani fungus including two types of saffron organs (leaf and corm) and seven extract concentrations (0, 1, 0.5, 25. 0, 0.125, 0.625, and 0.0312 w/v %). The results showed that the type of extract has an effect on the germination percentage, germination rate, mean germination time, length and fresh and dry weight of radicle, the length, fresh and dry weight of the plumule, seedling dry weight, and the seedling vigor of London rocket were significant, and the corm extract had more negative effects compared to the leaf extract. As the extract concentration increased, its inhibitory effect also increased. The extract concentration of 4% significantly reduced the radicle length and fresh and dry weight, the plumule length and fresh and dry weight, seedling dry weight, and seedling vigor of London rocket compared to the control. The results of the interaction showed that the lowest percentage of germination, germination rate, radicle length and fresh and dry weight, plumule fresh and dry weight and seedling dry weight of london rocket were observed at the concentration of 4 % corm extract. The results of the interaction effect of extract type and extract concentrations on Fusarium solani colony diameter showed that all the concentrations of corm extract inhibited the growth of Fusarium solani in all four stages of sampling. In leaf extract, concentrations of 0.125, 0.25, 0.5 and 1% completely inhibited the growth of Fusarium solani in all four stages of sampling. Finally, the results of these experiments showed that the effect of inhibiting the germination and growth of london rocket as well as the antifungal effect is greater in saffron corm extract than the leaf extract. Therefore, considering the results of this research and conducting more research in the field of allelopathic and fungicidal effects of saffron organ extracts, we can proceed to produce natural herbicides and fungicides.

In order to investigate the effect of biopriming of wheat seeds with Trichoderma and Aspergillusalong with ZnSo4 on improving germination indices and the tolerance threshold of wheat to zinc a factorial experiment was done based on a completely randomized design with three replications. Experimental treatments included six levels of zinc (0, 0.6, 6, 60, 300 and 600 mg/L) and four fungal treatments (no inoculation, inoculation with Trichoderma harzianum, Trichoderma longibrachiatum and Aspergillus niger). Nonetheless, based on the results, the coexistence of wheat seedlings with Trichoderma fungi especially Aspergillus fungi reduced the lipid peroxidation of the membrane in all application levels of zinc. Also, based on the results, the highest proline content was observed in the highest level of zinc in inoculated wheat seedlings by T. harzianum (fourfold increase as compared to the uninoculated control) and in other levels of zinc in seedlings inoculated with A. niger. However, the results showed a negative relationship between malondialdehyde (MDA) content and superoxide dismutase (SOD) activity and growth indices of wheat seedlings. There was also a negative relationship between MDAecontent with both SOD activity and growth indices of wheat seedlings. Inoculation of wheat seedlings with fungal treatments with higher production of SOD may led to higher resistance and avoidance to higher concentrations of Zn. Overall, the results showed an increase in the tolerance threshold of wheat seedlings to a concentration of 60 mg/L and therefore, more effectiveness of this micronutrient in seeds inoculated with Trichoderma and Aspergillus especially inoculated with Trichoderma longibrachiatum.

Trichoderma and vermicompost are important factors in improving and indirect growth stimulants in a variety of crops and orchards. This study is a factorial experiment based on a completely randomized design, under soilless cultivation conditions in the greenhouse, with 4 concentrations of Trichoderma harizianum isolate Bi: 0% (control), 10%, 20%, and 30% by volume of 60 liters of water and two levels of vermicompost: Control (no use of vermicompost) and 50% of pot volume (cocopeat and perlite (2:1)) with 6 replications were established by studying the effect on morphological properties of lettuce cultivar (Green Tower Mi). The highest weight of stem, leaf, and root based on the results of the 10% fungus concentration treatment was observed at the highest levels of 363.75 g, 325.08 g, and 26.35 g, respectively. Also, in the application of vermicompost, the heavier stem fresh weight (377.41 g), leaf fresh weight (348.87 g), and root fresh weight (24.11 g) had the highest weight compared to non-application. The highest number of leaves (36), stem diameter (20.64 mm), and leaf area (211.25 cm-2 g) were observed in fungal treatment with a concentration of 10%. The antioxidant activity of lettuce treated with vermicompost increased by 25.34% compared to the control. Therefore, with the positive effect of vermicompost and Trichoderma on the growth properties of lettuce, the use of these two treatments in planting this plant is recommended. Also, because there was no significant difference between the high levels of the fungus, it is possible to achieve the desired result with fewer savings and costs, even with a concentration of 10% fungus.

In this study, the antagonistic activities of eleven isolates belonging to 10 species of Trichoderma fungi including Trichoderma harzianum, T. atroviride (two isolates), T. viride, T. orientalis, T. citrinoviride, T. asperellum, T. spirale, T. crassum, T. pseudokoningi and T. ceramicum against rhizoctonia solani AG2-2, the causal agent of sugar beet root rot, were evaluated in a completely randomized design with four replications. Results showed that all Trichoderma isolates reduced the growth of pathogen significantly and the highest antagonistic effects were observed in dual culturing test in T. harzianum Z1 isolate, which caused 76.57% inhibition of pathogen mycelial growth. In greenhouse experiments, the efficacy of four selected Trichoderma isolates on sugar beet root rot control in Shirin cultivar was evaluated. Results showed that T. harzianum Z1, T. atroviride Z2, and T. orientalis Z4 caused 71.1, 66.6, and 58.3% decrease in root rot severity, respectively. In field experiments (2013-14) conducted in Hamedan Agricultural and Natural Resources Research Center, the effect of selected Trichoderma isolates in comparison with fungal treatment (carboxin-thiram) and control treatment on the occurrence and severity of root rot was evaluated through artificial contamination by Rhizoctonia solani. Results showed that selected Trichoderma isolates were significantly different in terms of disease control and T. harzianum Z1 isolate caused 66.4% reduction in the incidence of infection and 56% reduction in root rot severity compared with control. Therefore, this isolate is considered as the most effective antagonist in decreasing of Rhizoctonia root rot disease of sugar beet root.

Barnyardgrass (Echinochloa spp.) is the most important weeds in rice fields. Funguses species play important roles in biological control of the weeds, especially Echinochloain rice fields. In this research, Fusarium equiseti and Colletotrichum graminicola were isolated from E. oryzicolaandE. crus-galli and their pathogenicity effects were compared on these weeds and five rice genotypes in a completely randomized design with three replications. Two net fungi were inoculated on weeds and rice genotypes using a spore suspension consisting of 106 spore·ml-1 of distilled water. Genotype-by-pathogen biplot analysis was down for illustration of pathogenicity of two fungi (as pathogen) on host genotypes to facilitate the simultaneously visualization of relationship among pathogens and genotypes.The significant effects of pathogens were observed on disease rate and reduction of plant height, dry and fresh weight of plantlets. Biplot analysis indicated a differential interaction between pathogens and rice and Echinochloa genotypes for the studied traits. Average-tester-coordination (ATC) view of biplot indicated that Sepidroud and Binam were as the most sensitive and tolerant genotypes to two mentioned fungi according to their disease rating. The relationships view of biplot indicated there were higher positive correlations between diease rate and reduction in plantlet dry weight. Hashemi cultivar located near the biplot origin and had a horizontal resistance to fungi and can be used to biological control of barnyardgrass in the filed of this cultivar. In conclusion, the results of this study based on the severityof the disease showed thatC. graminicolafungus had more antagonistic effectsthanF. equiseti, especialy on E. crus-galli.

Biological fertilizers have a potential role to increase soil nutrient and reduce dependence on expensive chemical fertilisers. Present study was conducted to evaluate the effect of municipal compost and vermicompost on qualitative and quantitative traits of cotton (Varamin cultivar) at 2015-2016 cropping year. The experiment was based on completely randomized block design with 10 treatments at three replications in research field station of Agricultural Jihad and Natural Resources of Tehran Province at Varamin region, Iran. In this research the factors like plant height, vegetative and reproductive branch number, and number of bolls, 20-bolls weight at the harvesting time, cotton yield were evaluated. The results of analysis of variance showed that compost and vermicompost as biological fertilizers significantly affected whole studied traits (P<0.05). Application of biological fertilizers resulted to increase in plant height, vegetative and reproductive branch number, and number of bolls, 20-bolls weight and cotton yield. Among treatments, vermicompost application (20 ton/ha) had highest bolls number and 40 ton/ha vermicompost resulted to highest plant height (149.78 cm) and reproductive branches (26 branches) and 20-bolls weight. In the most of studied traits, vermicompost treatment had highest amounts. Totally, the results of present study showed that application of compost and vermicompost fertilizers could have efficient contribution in increasing efficiency of cotton plant production.

Saffron (Crocus sativus L.) is the most important plant in the world that has been used in cooking, confectionery and drug productions because of the color and aromatic substances in its sigma. Corm rot disease is one of the most important diseases in Iran. For identification of causal agents, wild saffron plants with wilt symptoms and rot lesions on corm were randomly collected in different regions of Ivan and Mehran in the Ilam province. Diseased samples were surface sterilized by dipping into domestic bleach solution (5% NaOCl). Then they were washed three times with sterile distilled water, dried with sterile filter paper and plated on potato dextrose agar (PDA). Samples were incubated for three days in an incubator at 20°C. A total of eight Fusarium isolates were obtained and purified using the single spore method. Fusarium oxysporium isolates were identified according to their morphological and microscopic characteristics as described by the identification key. The pathogenicity of Fusarium oxysporium isolates were artificially tested in the greenhouse on a wild susceptible cultivar according to Koch’s principles.

This study investigated the influence of inoculation with an arbuscular mycorrhizal fungus (AMF), Glomus mosseae (Nicol & Gerd.) on growth and antioxidant enzyme activities (SOD, CAT, GUPX) in shoots and roots of wheat (Triticum aestivum L.) affected by three different levels of salt stress. The experiment was arranged as a factorial in Randomized Complete Block Design (RCBD) with three replications. Experimental treatments including: three levels of salinity stress (0 (control), 60 and 120 µm) and two levels of inoculation (inoculation and non inoculation). Salinity decreased wheat growth, regardless of the mycorrhizal treatment and the salt stress level. The plants inoculated with AMF had significantly greater shoot biomass than the control plants at all salinity levels. However, the results pointed out that salinity had inhibitory effects on mycorrhizal infection. The highest mycorrhizal infection was observed in the control plants. Increasing salinity stress raised significantly the antioxidant enzyme activities, including those of total SOD, GUPX and CAT, of wheat compared to their respective non-stressed controls. The AMF induced a higher increase in these antioxidant enzymes in response to severe salinity. Inoculation with AMF could serve as a useful tool for alleviating salinity stress in salt-sensitive plants. However, Analysis of variance indicated that there was not significant interaction between salt and mycorrhizal inoculation on SOD and CAT of roots. Also, there was not significant interaction between salt and mycorrhizal inoculation on GUPX in both shoots and roots.

To investigate the antifungal effects of essential oils of Khuzestani savory (Satureja khuzistanica Jamzad)، Rechingeri savory (S. rechingeri Jamzad)، carvacrol and Benomyl on Botrytis cinerea، this study was carried out in a PDA medium، and on grapes، kiwi fruits and strawberry. The experiment was laid out factorially based on a completely randomized design with three replications. The results showed that essential oil of Khuzestani savory، Carvacrol and Benomyl had greater antifungal effects compared with that in essential oil of Rechingeri savory. The main components of essential oil of Khuzestani savory were Carvacrol (91. 16 Percent)، p-Cymene (1. 26 Percent)، γ-Terpenen (0. 74 Percent). The main components of essential oil of Rechingeri savory were Carvacrol (77. 2 Percent)، p-Cymene (1. 26 Percent)، γ-Terpenen (1. 62 Percent). Essential oil of Khuzestani savory with concentrations of 200 ml، Carvacrol and Benomyl in all concentrations used showed 100 percent fungal inhibitory effects. The results of experiments in medium and on fruits showed that the antifungal effects of essential oils increased as their concentration increased.

This study was conducted to evaluate the resistance of 70 genotypes of barley to powdery mildew. After preparing the samples contaminated with powdery mildew, reproduction of the spores of the fungus was conducted on susceptible cultivar Afzal. The experiment was conducted with randomized block design in pot in greenhouse. Seedlings were inoculated with the spores fungus in two-leaf stage. After 12 days, the traits of the infection type and infection intensity, assessed based on 0-9 Saari and Prescott scale. After comparing the means, to obtain an overall result, ranking of genotypes were conducted based on the comparison of means with Arunachalam method. The results showed that varieties Afzal, Rihane, Goharjow, EB-88-8, 45-Motadel, EC-83-17 and Fajre 30 received the highest ranking for infection type and disease intensity and were identified as susceptible and moderately susceptible genotypes. The genotypes EB-86-6, EB 87-20, Arass, EB-88-2, EBYT-W-89-4, EB-88-13, Dasht, MB-83-14, EBYT-W-89-3, NB17, 24 Garm, EB-89-19, EBYT-W-89-15 and W-79-10 allocated lowest ranking and found as resistance genotypes. The results of cluster analysis were endorsing the results of ranked Arunachalam. According to the analysis, genotypes were divided into four groups, resistant, moderately resistant, moderately susceptible and susceptible. Considerable estimate for phenotypic and genotypic coefficient of variation and broad heritability for infection type and infection intensity indicates selection likely can be effective in improvement of resistance to powdery mildew.

Nowadays, the use of biofertilizer is steadily increasing in sustainable agriculture, therefore the present study was aimed to evaluate the effect of seed biopriming by Piriformospora indica and Trichoderma virens on the growth, morphological and physiological parameters of mung bean (Vigna radiate L.). Experiment was conducted as completely randomized design with three replicates in 2014. Treatments were included four levels of biopriming (control, inoculation by P. indica or T. virens and dual inoculation by P. indica and T. virens). Seeds of mung bean were sown in sterile soil and grown for four weeks and then some morphological, growth and photosynthetic pigments parameters were determined. Results showed that seed biopriming by Trichoderma, P. indica and dual inoculation increased plant height (4, 8 and 2 %, respectively) and root length (18, 31 and 13 %, respectively) as compared to the uninoculated control. However, the increase was significant only for P. indica inoculated seeds. Furthermore, shoot fresh and dry weights increased when mung bean seeds inoculated by both fungi. The maximum increase in stem, shoot and plant dry weights (5, 3 and 2 times of control) were recorded when seeds inoculated with P. indica. Also, inoculation of seeds by P. indica improved chlorophyll a, b, a+b contents (nearly 8, 15 and 9 %, respectively). In conclusion, it seems that seed biopriming of mung bean by growth promoting fungi particularly P. indica positively improved the growth attributes in early growth stages.

To evaluate the effect of biofertilizers on yield and yield components of a soybean cultivar (M9) under water stress condition، a study was carried out in a split plot randomized complete block design with three replications at research station of Bu Ali Sina university in 2012. The main plots included three levels of irrigation after 50، 100 and 150 mm evaporation from A pan and subplots included four biofertilizer treatments (Bradyrhizobium japonicum، arbuscular mycorrhizae، both biofertilizers and no biofertilizer). Results showed a significant effect of water deficit on number of pods per area، grains per pod، plant height، biological yield، grain and oil yields but seed weight، harvest index and oil percent were not affected. In the absence of moisture stress، biofertilizers had no significant effect on the most of traits even mycorrhizae reduced the plant height. Greatest reduction in soybean yield was observed in severe stress but the use of biofertilizers especially in both biofertilizers the negative effect of water stress minimized. So، the number of pods per area، seed weight، plant height، biological yield، grain and oil yields increased، respectively 33، 9. 6، 15. 4، 90، 93 and 170 percent compared to severe water stress in no- biofertilizers treatment.

Pathogenicity of 4 isolates of Erysiphe betae from 4 different geographical zones of Iran on 5 genotypes of beet, with different levels of resistance to powdery mildew, was investigated. Eight-week old plants were inoculated by conidia from 4 isolates separately. Indices for infection were estimation of leaf infection and number of produced conidia on the leaf surface 3 weeks after inoculation. Results indicated that there was no significant difference on the virulence level of 4 isolates but the genotypes showed significant difference in susceptibility to fungal isolates. The genotype 7233 indicated the highest susceptibility and two genotypes 10417 and 14442 showed highly resistance to powdery mildew. The genotype “Leaf Beet” which in the field experiments in Germany had proved resistance to the disease, in our greenhouse studies showed susceptible response. Conclusive results indicated that different isolates of E. betae belonging to different geographical zones were similar in pathogenicity and also greenhouse experiments can be an appropriate manner for screening sugar beet genotypes against E. betae.

A total of 105 isolates of Erysiphe betae from different regions of Iran were investigated. For probable polymorphism of ITS-5.8S regions using PCR-based RFLP, the mentioned fragments were amplified via PCR by ITS1 and ITS4 primers and subjected to 1.5% agarose gel electrophoresis. PCR products were digested by HaeIII, AluI, TaqI, HindIII, CfoI, EcoRI, MspI, SacI and RsaI REs and the digestion products were resolved on 7.5% polyacrylamide. PCR product of all isolates was only one 645 bp fragment. Among nine REs tested AluI, CfoI, MspI and HaeIII had recognition sequences on PCR products. Because of unstability, results for AluI were ignored.Digestion products for CfoI were 280, 185 and 180bp, for MspI, 325, 160, 120 and 40bp and those of HaeIII, 325, 180, 75, 40 and 30bp fragments for all isolates. Electrophoretic patterns of PCR products and digested products were completely similar,thus no polymorphism was discernible between 105 isolates. Based on the results,Iranian populations of E.betae seems to be highly uniform.

This study was carried out to identify Fusarium species associated with sugar beet root rot and yellows. Pathogenicity of Fusarium oxysporum, the causal agent of Fusarium yellows of sugar beet was also investigated. Samples of infected roots were collected from fields in major sugar beet producing areas in Khorasan province during 1999-2000. Infected roots were washed, surface sterilised and plated on PDA. One hundred sixty eight isolates of Fusarium spp. were recovered. Seven species were identified including Fusarium solani (42 isolates), F. oxysporum (31 isolates), F. acuminatum (27 isolates), F. avenaceum (23 isolates), F. moniliforme (19 isolates), F. equiseti (16 isolates) and F. culmorum (10 isolates). All isolates of F. oxysporum were tested for their pathogenicity on seedlings and matured sugar beet plants. The results showed that 12 isolates (38.7%) of F. oxysporum were non-pathogenic, and 19 isolates (61.3%) were pathogenic.