روح الله صابری ریسه

The production of siderophore and cellulase by Trichoderma species is one of the effective indexs in plant growth, effective control and management of pathogens as well as application in industry. Therefore, primary screening of best isolates is very important based on the defined indicators.

In this study, the optimal conditions for the qualitative and quantitative production of siderophore and cellulase were investigated using test plate method for the initial screening of 27 Trichoderma strains. For measuring cellulase enzymes (Endoglucanase, exoglucanase and beta glucosidase), the reactive dyes phenol red, congo red (0.5, 0.05 and 0.015%) were used at pH levels of 4, 5, 7 and 9 with carbon sources including Avicel, CMC and cellobiose. Quantitative measurement of cellulase was investigated using the dinitrosalicylic acid method. Screening of Trichoderma strains for siderophore production was studied by CAS agar method as mycelial culture and crude extract in a well method.

The results of this research showed phenol red 0.015% under pH5 is the best reagent for detection of cellulase, Because of there is no inhibition on mycelial growth and the purple zone diameter is clear. In quantitative cellulase assay, the highest enzyme specific activity is related to T. harzianum CT-763 with 3 U/mg. T. atroviride CT-482, CT-473 and CT-865 were known as active strains in siderophore production, which were able to produce two types of siderophore, hydroximate and catechol. The results of siderophore production in liquid medium using the well method showed that T. afroharzianum CT-891 has the highest siderophore production by creating a halo zone of 1.2 cm, while T. harzianum CT566 produced the lowest amount of siderophore without creating halo.

Considering the application efficiency using of siderophore and cellulase in sustainable agriculture and importance of the role of Trichoderma species in production these metabolites, the well method for siderophore and dinitrosalicylic acid method for cellulase detection suggested. In this study T. atroviride and T. harzianum species had the highest production in siderophore and cellulase, respectively

Salinity can prevent the uptake of soil mineral ions due to the negative effect of sodium ions and disturbance of ion balance, but the use of Trichoderma biocompounds improves growth under salinity stress. To investigate the effect of four salinity-resistant Trichoderma strains on growth traits and mineral element uptake of eggplant seedlings under stress conditions, an experiment has been performed in a completely randomized factorial design with three replications in the greenhouse of Vali-e-Asr University of Rafsanjan during 2016-2017. The first factor is salinity in four levels including the control and concentrations of 8, 12, and 16 dS/m and the second factor is Trichoderma as T. aureoviride (T148-2, T189-4) and T. virens (T145, T133-1) as well as the control. The results show that under the influence of salinity, a significant decrease in growth traits takes place. At the highest salinity level, the average dry weight of roots and shoots is 50% and 72%, respectively. For stem diameter and seedling height, a 20% decrease is observed compared to the control. However, inoculation with Trichoderma improves these traits, resulting in a 1.6-fold increase in root dry weight (T142-8), a 2.7-fold increase in shoot dry weight (T133-1), and a 1.3-fold increase in seedling height (T189-4) in comparison to the control. The highest diameter increase could be observed in T142-8 strain by 38%. Using Trichoderma leads to significant changes in sugar, sodium, potassium, and calcium content. The results of this study show that Trichoderma can be a suitable biological agent to increase tolerance at high levels of salinity stress and improve the growth traits of eggplant seedlings.

Crown and root rot is one of the important diseases of citrus trees in Iran. Various methods, including biological control, have been proposed to control this disease. Trichoderma species are widely present in all soils and plant materials. In this study, 27 Trichoderma strains were used for biological control of Phytophthora citrophthora. Measurement of cellulase enzyme and beta 1-3 glucanase produced by Trichoderma spp. was done using the dinitrosalicylic acid method. The results showed that the highest values are related to T. harzianum CT-763 and T. virens CT-9715 strains with 2 µmol/ml enzyme activity. Macroscopic and microscopic examinations of the dualculture of different Trichoderma strains with the pathogen, the inhibitory effect of volatile and non-volatile metabolites on mycelial growth of the pathogen were done. All Trichoderma strains and their volatile and non-volatile compounds inhibited on pathogen mycelia growth. The highest percentage of inhibition dualculture tests was caused by T. virens CT-9715. The highest inhibitory effect was determined for T. afroharzianum CT-891, T. aureoviridis CT-936, T. atroviride CT-865 with 100% and T. afroharzianum CT-55 with 50% in the non-volatile and volatile compounds assay, respectively. In microscopic examination of mycoparasitism effect of Trichoderma spp. and P. citrophthora, it was found that T. harzianum (CT-566, CT-862, CT-634, CT-873), T. afroharzianum CT-55 and T. aureoviridis CT-936, destroyed the mycelium of pathogen by a process such as twisting and lysis. For application of these successful local strains as biopesticide, it is necessary to perform additional studies on their biocontrol effects on Phytophthora in natural conditions.

Gummosis (Phytophthora Crown and Root Rot) is one of the Most Important Diseases of Pistachio Trees. In Order to Evaluate the Relative Resistance of 29 Rootstocks of Pistacia to this Disease, a Factorial Experiment was Conducted with Two Factors Rootstocks Type and Disease Stress, Based on Completely Randomized Design with Three Replications. Two-Month-old Pistachio Seedlings were Artificially Inoculated with Phytophthora Drechsleri and After Six Months, Evaluation Was Done. The Resistance of Rootstocks was Evaluated by Determining the Percent of Crown Rot Girdling, Disease Severity and Mortality Indices and Measuring the Stem Length, Stem and Root Dry Weight Traits in Control and Stress levels. The Results Showed that There was a Significant Difference Between the Studied Rootstocks in Terms of Resistance to Disease. The Disease Stress Caused a Decrease in Stem Length, Stem and Root Dry Weight of Seedlings. The Atlantica Had the lowest Amount of Crown Girdling (20%) and Disease Severity (17%) and in Terms of Disease Severity, it Showed a Significant Difference with other Rootstocks. The Sarakhs Rootstock Had also the Highest Amount of Crown Girdling (95%), Disease Severity (90%) and Mortality (55.55%) and in Terms of These Indices, it was Significantly Different from other Rootstocks. Therefore, Atlantica was the most Resistant and Sarakhs the most Susceptible Pistacia Rootstocks Against Gummosis Disease. The Cluster Analysis Divided the Rootstocks into Four Groups: Resistant (Atlantica, Integerrima and UCB1), Moderately Resistant (Mutika, Benebaghi, Kalleghouchi, Ghazvini, Gholamrezaei, Italiaei, Ahmad Aghaei, M5 and BK1), and Moderately Susceptible and Susceptible .

Pistachio is one of the most important agricultural products and iran has the richest germplasm of pistachio in the world. The presence of this genetic resources will be an appropriate opportunity for use in breeding purposes. Knowledge of genetic relationships among pistachio genotypes has important role in it’s breeding programs. Molecular markers are one of the powerful tools for studying plant phylogenetic relationships. Start Codon Targeted (SCoT) technique is one of the molecular systems that used to assess the genetic relationship among different plant species and cultivars. This study was performed in order to evaluate the genetic relationships between a numbers of Pistacia species and cultivars using SCoT molecular markers and to assess the usefulness of this markers in differentiating this genus.

Plant materials of this study are included 29 genotypes of domestic and wild species of genus Pistacia. A total of 25 SCoT primers were used to evaluate the genetic relationships. Genomic DNA were extracted from leaf samples using CTAB method with minor modifications. The quantity and quality of the extracted DNA were measured by spectrophotometer and agarose gel electrophoresis. Cluster analysis based on Jaccard’s similarity matrix and complete linkage algorithm and Principal coordinate analysis were performed using NTSYSpc 2.02e software.

In total, 449 DNA fragments were amplified by primers out of which 433 bands (96/43%) were polymorphic. The average number of amplified fragments for each primer was 17.96 bands with a mean of 17.32 polymorphic bands per primer. A number of species-spicific marker were detected in some Genotypes. The average of polymorphism information content values varied from 0/18 to 0/38. Also, the values of marker indices ranged from 0/56 to 4/36. The range of similarity coefficients of genotypes varied between 25% to 68%. Cluster analysis divided Genotypes into two main cluster including vera (domestic) and wild species. Principal coordinate analysis separated vera cultivars and genotypes from wild species and confirmed the results of cluster analysis.

The results of this study demonstrated that SCoT molecular markers detected high polymorphism among pistachio species and cultivars and differentiated the studid genotypes. Therefore, SCoT Marker is a useful tool for studying phylogenetic relationships in genus Pistacia.

Pseudomonas fluorescens bacteria are the most important rhizosphere bacteria that have a positive effect on vegetative and biochemical traits of the plant. In this study, genetic diversity of 22 Pseudomonas fluorescens strains and their effect on defense enzymes and growth factors of wheat plant were performed in three stages of greenhouse, molecular and biochemical evaluation. In molecular evaluation, 12 RAPD primers were used to evaluate the genetic diversity of strains. Biochemical evaluation was performed in 4 stages of 0, 3, 6 and 9 days after inoculation on wheat to measure the defense enzymes peroxidase and phenylalanine ammonialyase. VUPF5 strain on wheat increased shoot and biological weight. RAPD-PCR separated strains with similar geographic location and similar host. Greenhouse, molecular, and biochemical groupings identified almost the top strains. Strains 680, 738, 50, 354, 49, 58 and VUPF5, which had a positive effect on molecular evaluation in one group, were shared with the superior group of enzymes. T26-2 and F-68 in OP-I15 and OP-H8 primers amplified 1300 bp and 1200 bp bands, respectively witch these bands can evaluated after be further studies as candidate bands in the expression of these enzymes in wheat.

Due to the importance of mycorrhizal fungi and their ability in colonization of plants, the use of some microorganisms and chemical compounds to improve mycorrhizal activity is an important issue. In this study, an experminet  was conducted as a compeletely randomized factorial desin with  three replications at Valiasr University of Rafsanjan.Three fungal species, Funneliformis mosseae(FM), Rhizophagus intraradices(RI) and Rhizophagus irregalaris (RIr) were applied asmycorrhizal inoculant and the effect of some microorganisms including yeast (Issatchenkia orientalis) and bacteria (Pseudomonas fluorescens VUPf5) as well as chemical compounds such as compost tea, azolla extract, bacterial siderophore, humic acid and amino acid complex on fungal activity and physiological parameters of corn plant (SC750 cultivar) was examined. The results showed that all species of mycorrhizal fungi combined with bacterial treatment and chemical compounds had a significant effect on stem diameter and longitudinal growth, leaf area increase, root weight and dry weight and shoot dry weight. Variance analysis of SPAD showed that there was not significant difference between mycorrhizal and non-mycorrhizal treatments. However, the application of different species of mycorrhizal fungi had a significant effect on the content of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids in compared to the control (without mycorrhizal fungus) treatment. The use of humic acid and compost had the extreme effect on plant growth. Amino acid complex treatment with Rhizophagus intraradices had the greatest effect on chlorophyll a, chlorophyll b and total chlorophyll content. The treatments of yeast and amino acid complex had the greatest effect on carotenoids, respectively..

Identifying resistant genotypes is necessary to control wheat take-all disease Gaeumannomyces graminis var. tritici. In this study, 30 bread wheat genotypes were evaluated under greenhouse and field conditions. The genotypes were evaluated with fifteen molecular markers (SSR and specific primers for translocation wheat-rye). The genotypes were divided into four groups based on disease severity (the greenhouse) and agronomic traits (the field). Chi-square results showed the interactions for these groupings. The correlation between disease severity and agronomic traits indicated that plant resistance is strongly dependent on plant yield. Based on cluster analysis for molecular data (based on simple matching similarity coefficient and UPGMA method), genotypes were separated into resistant and susceptible ones. The correlation between disease severity and amplified loci showed that disease resistance is interactive with xbarc232, xbarc124, and gpw95001 markers. Resistance to take-all disease is probably associated with the interaction of several genes. These results add significant information to our knowledge of the chromosomal location of genes for the take-all disease.

Take-all is a devastating soil-borne disease of wheat Triticum aestivum L. The disease is caused by the pathogenic fungus Gaeumannomyces tritici, a pathogen distributed worldwide in major wheat production areas that causes severe damage to wheat production. Identification of genotypes with the high nutritional value of seeds can be considered in controlling this disease and in wheat breeding programs. Variation of high molecular weight glutenin subunits (HMW-GS) at the Glu-A1, Glu-B1, and Glu-D1 loci was studied using SDS-PAGE electrophoresis in 15 genotypes of bread wheat. A positive correlation was found between 1000-seed weight and the 5 + 10 allele (r = 0.594), indicating that presence of this allele will increase 1000-seed weight. A simple corresponding analysis was conducted to show the relationship between the take-all index and the genetic diversity of genotypes and the association between the bilateral groupings of individuals based on two criteria (genetic diversity and disease response). The result of stepwise regression showed that glutenin subunit null, 7 + 8, 2*, 7 + 9, 5 + 10 have linkage with resistance to take-all disease. Findings are useful in breeding programs to improve baking quality, develop uniformity and improve heterogeneous genotypes by selecting the best genotypes.

The current study evaluated Pseudomonas fluorescens VUPf5 and three isolates of Bacillus subtilis (GB32, GB12, and VRU1) for induction of resistance against Cucumber mosaic virus (CMV) in cucumber Cucumis sativus L. (cultivar Sultan) plants. Seed treatment with plant growth-promoting rhizobacteria (PGPR) strains significantly reduced the number of symptomatic plants when CMV was mechanically inoculated. Serological analysis using double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) also showed a significant reduction in the CMV accumulation in plants treated with PGPR strains. In every treatment, growth indices, leaf chlorophyll content, leaf carotenoid content, leaf, and root Iron, Zinc, Copper, and Manganese concentration of virus-infected plants were significantly increased. The highest reduction in CMV concentration was observed in plants treated with VRU1. The maximum chlorophyll concentration, leaf Iron, copper, and manganese were observed in plants treated with GB32.
Nevertheless, the highest carotenoid content was measured in the VUPf5 treatment. In the case of growth indices, the best results were obtained by VUPf5 compared to untreated control. In addition, the production of lipase, siderophore, protease, cellulase, HCN, auxin, and phosphate carbonate was determined under in vitro conditions. All four strains were positive for siderophore and auxin production. These results suggest that P. fluorescens and B. subtilis should be further evaluated for their potential to contribute to CMV management under in vivo and in situ conditions.

Phosphorus is one of the essential elements for plant growth and increase in the availability of indigenous phosphorus have an effective role in reducing the chemical fertilizers consumption. This study was conducted to investigate some inoculant formulations for phosphate-solubilizing fluorescent pseudomonads for agricultural and environmental uses. For this purpose, 30 isolates belong to fluorescent pseudomonad group were collected from microbial bank of Faculty of Agriculture of Vali-e-asr University of Rarsanjan. Then ability of all isolates for solubilizing tricalcium phosphate were studied. In addition, the ability of those isolates for increasing phosphorus availability in soil amended with and without phosphate rock at 15, 30 and 60 days was inspected. Finally, the persistence of the selected isolate was evaluated in some inoculant formulations. The results indicated that all isolates were able to increase the solubility of tricalcium phosphate in solid and liquid media of PKV and the pH of culture medium also decreased significantly. The maximum and minimum phosphate solubilization in solid media of PKV were related to isolates D33 and D24 and in liquid media, it was related to isolates D6 and D4 respectively. The results showed that isolates D33 and D35 increased the soil phosphorus bioavailability in 15, 30, 60 day after inoculation by 48, 25, 75% and 72, 50, 26% respectively. The cell numbers of D33 and D35 isolates in three inoculant formulations including talcum powder, talcum+rice bran and talcum+sawdust (180 days after inoculation) indicated that maximum and minimum of cell numbers of D33 were occurred in talcum powder and talcum+rice bran (105 cfu/g) and talcum+sawdust (8×103 cfu/g)  respectively. Maximum and minimum of cell numbers of D35 were observed in talcum+rice bran (105 cfu/g) and talcum+sawdust (10 cfu/g) respectively. Finally, inoculant formulation of talcum+rice bran was able to maintained an acceptable cell numbers of both isolates D33 and D35 (106 cfu/g) at the end of 150 days.

Introduction:

 Rising global demand for food, along with the limitation of arable land, has posed a significant challenge on agricultural researchers to find solutions to overcome this issue. Given that the development of agricultural lands is not practically possible, most attention should be focused on increasing the production yield per unit area. One of the basic approaches to increase crop yield is the consumption of chemical fertilizers, although their application has detrimental effects on humans, soil and the environment. However, organic fertilizers can be considered as a suitable solution to solve this problem. Organic compounds and biomass are the main features of soil fertility and productivity. Applying organic fertilizers such as living compounds (bacteria, yeast, Azolla) and non-living compounds (compost tea, amino acids, humic acid and fulvic acid) can increase soil organic substances. Arbuscular Mycorrhizal Fungi (AMF) are considered as beneficial microorganisms promoting plant growth by establishing a symbiotic relationship with plants. The colonization of plant roots by these fungi increases plant resistance to biotic and abiotic stresses, enhances the plant growth through increasing elements uptake, the improvement of the water flow of plants, and the protection of the plants against diseases. Due to the importance of some food products, such as maize, investigating various aspects of mycorrhizal fungi application and their effect on these products is essential.

Materials and Methods:

 to investigate the effects of some organic compounds and microorganisms on the colonization of AMF and the concentration of some elements, a factorial experiment in greenhouse conditions was conducted in a completely randomized design at three replications for 3 months. The factors included mychorhizal inoculation consisted of Funneliformis mosseae (FM), Rhizophagus intraradices (RI), Rhizophagus irregalaris (RIr), and organic growth enhancers (Azolla, P. fluorescens VUPf5, amino acid complex, humic acid, yeast, bacterial siderophore and compost tea).

Results and Discussion:

 the results showed that the highest root mycorrhizal colonization percentage by Funneliformis mosseae (FM) was observed in bacterial (93%), humic acid (90%) and Azola (76%) treatments. The use of Azola and humic acid and compost tea showed the highest R. intraradices (Ir) root colonization with 96 and 82%, respectively. The highest effect of the treatments on R. irregalaris (Rir) root colonization was observed regarding Azola (96%) and compost tea (90%), respectively. According to the results, the prominent increase in root colonization by three mycorrhizal species was observed in Azola, humic acid, compost tea and bacterial treatments. In addition, the results showed that some compounds increased the concentration of nutrients in the roots and shoots of the treated plants. According to the results, all mycorrhizal species significantly increased the amount of phosphorus in the shoot under the compost tea treatment. Also, the treatment of amino acid combined with R. irregaluris caused an increase in the concentration of iron, compared to the control. The use of R. intraradices along with amino acid increased manganese concentration in the plant aboveground organs by 2.87 times compared to the control. Simultaneous application of siderophore and RI, FM and Rir increased the zinc concentration by 2.16, 2.55 and 1.81 times compared to the control, respectively. The highest uptake of phosphorus, zinc and manganese was observed by R. intraradices soil inoculation and the maximum iron concentration was obtained in plants inoculated with R. irregaluris. The mean comparison of different treatments revealed no significant differences between non-mycorrhiza and mycorrhiza-treated samples, while in comparison with the control, their differences were substantial. Overall, co-treatment of mycorrhizal fungi and Azolla, bacterial and humic acid caused the most significant increase in the mycorrhizal root colonization and the compost tea, amino acid complex and siderophore treatments had the highest impact on the nutrient content of the plant.

In the present study, all treatments had an additive effect on root colonization. However, Azolla, bacteria, humic acid and tea compost treatments caused the most mycorrhizal colonization. These treatments utilized with mycorrhizal fungus had a favourable effect on the growth factors of corn by increasing the rate of colonization. Also, this study revealed that all three species of mycorrhizal fungi increased the concentration of elements and the effect of these fungi along with compost tea, amino acid complex and bacterial siderophore increased colonization and nutrient content in the shoots compared to the control group.

Drought stress is one of the most important abiotic stresses and limiting factors for plant development and plant production. In order to evaluate the impact of concomitant application some of microorganisms and chemical compounds with three species of arbuscular mycorrhizal fungi Funneliformis mosseae, Rhizophagus intraradices and Claroideoglomus etunicatum as mycorrhizal inoculum on antioxidant enzymes activities and phenolic compounds in corn cultivar 705SC, an experiment was conducted in a randomized complete block design with three replications. In the present study, treatment of living and non-living compounds at seven levels (included Pseudomonas flurescens VUPF5, Issatchenkia orientalis yeast, Azolla, compost tea, humic acid, siderophore biologist, amino acid complex), treatment of arbuscular mycorrhizal (included three species of fungi and control) and drought stress at one level (30% of field capacity) were examined. Six, twelve and eighteen days after the start of drought stress, the interaction effect of treatments with species of arbuscular mycorrhiza on the activity of peroxidase, polyphenol oxidase, phenylalanine ammonialyase enzymes and total phenol was evaluated. According to the results, in all three fungal species, the activity of peroxidase enzyme in siderophore treatment with fungus was higher compared to other treatments. Also, the highest activity of polyphenol oxidase enzyme was observed in R. intraradices mixed with compost tea treatment. Phenolic compounds in mycorrhizal plants and non-mycorrhizal plants reached the highest level on the twelfth day, depending on the treatment and type of fungal species. In conclusion, among the different treatments inoculated with corn, amino acid complex, siderophore, tea compost and humic acid increased antioxidant enzyme activity compared to the control treatment and reached its maximum on the twelfth day..

Take-all disease, caused by Gaeumannomyces graminis var. tritici (Ggt) is one of the most important of wheat diseases that causes severe damage to crown and root rot in different regions of Iran. Development of resistant varieties requires genetic study on inheritance and type of gene action in disease resistance, which so far has not been any report in relation to (Ggt). Therefore, in order to genetically analyze of resistance to this disease, the generations of P1, P2, F1, F2, BC1 and BC2 were produced and planted at greenhouse. After artificial infection of plants with T-41 strain of (Ggt), the phenotypic measurement was based on the degree of disease damage and its symptoms on the crown and root were recorded. The results of the generation mean analysis indicated that the five-parameter model can explain the variations between the means of generations in two crosses (1528×164 and 1622×1526) and four parametric models in third cross(1528×1546). Additive, dominance and epistatic effects including additive × dominance and dominance × dominance were exist in controlling of this trait. The dominance and epistatic effects were greater than the others. Distribution of F2 generations, showed a tendency toward susceptibility so the susceptibility was dominant to resistance. Analysis of the F2 data based on the classical ratios showed that with phenotypic grouping of F2 generation in three susceptible, semi-susceptible and resistant groups. These three groups corresponded to the epistatic ratio (9:6:1), respectively. This result was almost consistent with the results obtained from the Generation means analysis, since in GMA, duplicate dominant epitasis and partial duplicate interaction were detected and the minimum number of genes involved in controlling this trait has been estimated by 2 gene that it has a relative accordance by duplicate dominant interaction with additive effect (9:6:1).

Take-all is one of the most important diseases of wheat in wet areas, causing significant damage in these areas, and there has not introduced any resistant varieties against this disease until now. Therefore, efforts to identify the resistance genes to this disease and developing resistant varieties or cultivars with lower susceptible in bread wheat have a great importance.In this research, in order to identify the markers related to resistance to a isolate of take-all (T-41), a population of F2 derived from crosses of susceptible genotypes (1546 and 164) with resistant genotype (1528) and bulk segregate analysis (BSA) where used. After planting the F2 population and parents in the greenhouse and artificial infection the plants with the fungus, the plant phenotype was determined according to the amount of contamination by scoring. After DNA extraction of parents and F2 population, two bulk of DNA was prepared from resistant and susceptible individuals based on disease scores. The bulks and parental DNAs where analyzed by RAPD, SCoT, ISSR and SSR primers and PCR reaction. Among the primers are used, only one ISSR primer produced a band of 400 bp in the resistant parent and bulk which was not found in the susceptible parent and bulk. Then, all individuals of bulks and F2 where genotyped for this marker and regression and chi-square analysis showed a significant relationship between this marker and the disease score. The regrsion of disease score on band 400bp (b = -0.709) indicates that this band is more abundant in low scores (resistant individuals). Also, the distribution of F2 individuals in one of the crosses confirmed the existence of the epistatic (9sensetive: 6 semi sensitive: 1resistance) relationship

Five fungicides, with active ingredients azoxystrobin, imazalil, thiabendazole, azoxystrobin + difenoconazole and fludioxonil + difenoconazole, were tested against two isolates of Fusarium solani and two isolates of F. oxysporum, causing potato dry rot in Mashhad region. PDA media amended with the fungicides significantly inhibited the mycelia growth of all Fusarium isolates incubated at 25 °C for 7 days; however only Imazalil and Thiabendazole completely stopped the mycelia growth of all fungal isolates even at their lower concentration (40 and 5ppm respectively). The mean penetration of F. solani FPO-67 and F. oxysporum FPO-39, the more virulent of the four isolates, after 21 days of incubation at 25-27 °C indicated that imazalil and thiabendazole at concentrations of 1.5 and 2/1000, completely inhibited the penetration of F. oxysporum FPO-39 into potato tubers, but in the case of F. solani FPO-67 all treatments (1, 1.5 and 2/1000) significantly reduced the development of dry rot compared to untreated control. In natural condition, tuber treatment with Imazalil and Thiabendazole (2/1000), prior storage, reduced F. solani FPO-67 development by 68 and 71.69% respectively. According to the results, these fungicides could play a role in integrated pest management against tuber-borne fungal pathogens.

Walnut is one of the important nuts with a high economic value. Shallow bark canker, caused by Brenneria nigrifluens, is one of the most dangerous diseases of the walnut trees. Early detection of the causal agent has an important role in preventing economic and irreparable losses caused by this disease. In this study, 57 bacterial strains were isolated from walnut trees with the typical lesions of the shallow bark cankers from different regions of Kerman province. These isolates were divided into two groups, based on phenotypic and biochemical characteristics and then, amplification product of the expected size (255 bp) was obtained with genomic DNA using specific pair primers in B. nigrifluens isolates.Pathogenicities of the isolates were assessed on immature walnut fruits. To identify the causal and the associated bacteria molecularly, a part of 16s rDNA gene sequence was analyzed. Results showed that B. nigrifluens with a significant genetic diversity spread over different regions of Kerman province. In addition, the genus Gibbsiella can probably contribute to the increase of the disease severity, which requires further studies.

Gummosis (Crown and root rot) is the most important disease of pistachio trees caused by different species of Phytophthora which destroy significant numbers of fertile and non-fertile trees each year in Iran. Different approaches have been applied to reduce the severity and incidence of the disease. In recent years, biological control as an eco-friendly approach has been increased in the world. The effectiveness of Talk powder and Wheat bran formulations of five Pseudomonas strains (T17-4, VUPF760, VUPF5, VUPF506, and CHA0) was assessed on seedlings inoculated with Phytophthora drechsleri under greenhouse conditions. The highest and lowest reduction rates of disease severity belonged to VUPF760 and VUPF506 with 55 and 11%, respectively compared to the control and other treatments. Seedling inoculated with bacterial strains had higher heights, fresh and dry weights of shoot and roots. VUPF5 increased the ratios of height, fresh and dry weight of shoot and root by 1.4, 1.3, 1.1, 1.2, and 1.1 respectively, compared to non-inoculated control seedlings.

Trichoderma species are dominant organisms in most of soil microflora due to metabolic diversity and competitiveness and found approximately in all diverse habitats. In this study, four selected Trichoderma strains were evaluated to better control of cucumber stem and root rot disease caused by Fusarium solani. Cucumber germinated seeds were sown into inoculated soil with Trichoderma strains. Cucumber seedlings at forth leaf stages were inoculated with Fusarium. One month after inoculation by Fusarium, biocontrol effect of Trichoderma strains were evaluated by measuring the disease severity and cucumber growth factors. The results showed that Trichoderma strains were reduced disease severity and increased the growth factors in which both strains T189-4 (T. aureoviride) and T127-12 (T. harzianum) had the greatest impact on reducing infection with 91.67% in compare to untreated plants. The effect of Trichoderma strains on plant growth factors including root and stem length, dry and wet weight of root and stem, stem diameter and relative chlorophyll resulted that different Trichoderma strains have a posetive effects on increasing plant growth factors in which the strains T189-4 and T127-12 had the greatest effect on root dry weight in the presence of the pathogen, with 97% and 82%, respectively. These results indicated that the use of these Trichoderma native strains could be recommended for the control of Fusarium stem and root rot in the integrated management program of disease.

Fusarium crown and root rot of cucumber caused by Fusarium oxysporum is one of the most important diseases in cucumber. Although various methods have been recommended to manage this disease, biological control is considered as an environmentally friendly method. In the present study, antagonistic effects of six Pseudomonas and Bacillus genera strains were investigated against F. oxysporum, where in vitro and in vivo assays were performed under drought stress. All of the strains were capable to inhibit the growth of F. oxysporum. The results of drought stress also indicated that the bacterial strains were able to tolerate different levels of drought stress. In general, Pseudomonas fluorescens VUPF5 caused the best inhibitory effect in all of the assays in vitro and under greenhouse conditions.

Cucumber is one of the most important crop in Iran. Pests and pathogens are the most important factors limiting its cultivation and lead to reduced yields. Biological control is condiderd as the best control method for soil-borne disease including Fusarium stem and root rot. In this study, antagonistic effects of Pseudomonas fluorescens strains on the important root rot pathogens of cucumber with dual culture method was examined in vitro. Strain VUPf760 showed the highest inhibition zone against Fusarium oxysporium and Fusarium solani with 9 and 7 mm, respectively. Inhibitory effects of these isolates on the disease was evaluated in the greenhouse. The results showed that seeds treatment with T17-4 and VUPf5 isolates reduced the severity of disease caused by F. oxysporum and F. solani by58 and 60%, respectively. In addition, all three isolates alone increased peroxidase activity, total phenols and polyphenol oxidase in cucumber seedlings. However, the activity of these enzymes were higher in treatments with combination of antagonist and pathogen.

To study the effect of bacterial siderophore on the second cropping of maize (SC645) under drought stress conditions, a factorial experiment was arranged in a randomized complete block design with three replications. Two irrigation treatments (75 (I1: unstressed control) and 120 mm evaporation from Class-A pan (I2: delayed irrigation)) and two siderophore application treatments (S1: with and S2: without application) were considered as experimental factors. The foliar application of siderophore (2000 mg l-1) were applied two times at 4-6 and 12-14 leaf growth stages. In addition, 20 Kg siderophore ha-1 was applied with irrigation at jointing stage. The results showed leaf pigments, leaf relative water content (RWC), membrane stability, leaf area index(LAI) and specific leaf area (SLA) increased at I1 compared to I2, while sucrose (saccharose), lipids peroxidation (MDA), guaiacol peroxidase and polyphenol oxidase activities decreased. S1 compared to S2, showed increased leaf pigments, the ability of osmotic adjustment, antioxidant enzymes activities, RWC, membrane stability, LAI and SLA and decreased MDA. The interaction effect showed that siderophore application increase chlorophylls (a, b and total), proline and soluble sugars of leaf in each irrigation levels. The highest forage fresh yield (8697 gm-2) belonged to I1. S1 increased forage fresh yield (1644 gm-2) compared to S2. In general, bacterial siderophore can improve the morphological, physiological and biochemical capabilities of maize and is effective in mitigating the effects of drought and in increasing photosynthetic capacity.

Bread wheat is a valuable food sources that has been attacked by many diseases and reduces its quantity and quality. One of the major diseases of wheat is wheat take-all caused by Gaeumannomycs graminis var. tritici that is often prevalence in humid regions. Aim of this study was to evaluate bread wheat cultivars with different levels of resistance to take-all that had been selected from screening at greenhouse, in field conditions and study on relationship between the disease resistance index and agronomic traits and micronutrients. For this purpose, 15 genotypes were planted in infected and non-infected conditions at field and the traits: chlorophyll, carotenoids, flag leaf area, height, number of spikelets per spike, spike length, peduncle length, 100kernel weight, seed weight per spike, number of grains per spike, total grain weight per plant, biological weight, harvest index and micronutrients in grain (Fe, Mn and Zn) were measured. The amount of Fe (in grain) in infected treatment showed a significant increase in compared to control. Finally genotypes 485, 1528, 501, 8031 and 585 were better than the others in the point of above traits at infected environment. The results showed that disease index measured in the greenhouse had a negative correlation with plant height, seed weight per spike, flag leaf area, 100kernel weight and amount of grain iron in infected conditions at field shows that greenhouse evaluations can be used for selection of tolerant genotypes to take-all disease.

In order to determine the most efficient chemical compound in fluctuation of plant defense enzymes level and causing resistance to Phytophthora drechsleri in two pistachio cultivars (Sarakhs and Badami-riz-Zarand), a factorial experiment was carried out based on complete randomized design (CRD) with chemical compounds (potassium phosphite, fosetyl-aluminium, potassium silicate, complex amino acid, and siderophore). The results indicated that chemicals used for this experiment were able to reduce the percentage of death in pistachio seedlings as plants treated with potassium phosphite and amino acid complex with 100% and fosetyl-aluminium with 25% had the most and the least effects in these reduction of disease incidence, respectively. These compounds increased plants height, roots, and shoot fresh and dry weights in comparison to the control and inoculated plants with P. drechsleri. The results indicated that chemical compounds used for this experiment were able to reduce the percentage of death in seedling. Plants treated with pottasium phosphite Chemical compounds also enhanced enzymatic levels and phenolic compound content, which phenomenon was more obvious in simultaneous inoculation with disease agent and lead to enhancing the peroxidase, poly phenol oxidase, phenylalanin aminolyase enzymatic level, and total phenolic compound content.

To study the effect of bacterial siderophore on the second crop of maize (SC645) under drought stress conditions, a split-factorial experiment, arranged in a randomized complete block design with three replications was conducted in Faculty of Agriculture, Vali-e-Asr University of Rafsanjan at summer 2014. Sampling time was considered as main factor. Five samplings were performed after imposing the irrigation treatments. The factorial combination of two irrigation intervals (75 (unstressed control) and 120 mm evaporation from Class-A pan) and two siderophore application treatments (with and without application) were considered as sub factors. The foliar application of siderophore (2000 mg l-1) was applied two times. In addition, 20 kg siderophore ha-1 was applied with irrigation. The chl a, b and carotenoids decreased with delay in irrigation while increased with siderophore application in each irrigation. Also, proline, soluble sugars and sucrose accumulated with increasing irrigation intervals and delay in irrigation. Increase in intervals and delay in irrigation without siderophore application resulted in an increase in membrane lipid peroxidation. The trend of changes in traits was significantly influenced by the availability of soil moisture, and modifications in the above-mentioned trait values were observed with delays in irrigation. Irrigating (rewatering) of plants subjected to water deficit stress did not improve their traits values compared with the unstressed control, indicating that short-term effects of drought would not recover by irrigation. Bacterial siderophore enhances the ability of osmotic adjustment and photosynthetic capacity and is effective in ameliorating the harmful effects of drought.