Assessment of the Allelopathic Potential of Cumin Accessions in Different Soil Water Potential

Allelopathy is one effective solution to reach a healthy life without any pollution. This study was carried out to evaluate the allelopathic potential of 92 Iranian cumin accessions grown under normal conditions and drought stress, according to the sandwich method in the laboratory. In addition, weed infestation of the same cumin accessions was examined in a field by measuring total weed species richness and diversity under normal irrigating conditions. Results indicated that length and fresh weight of radish radicle and hypocotyl are more sensitive than the other germination indices against exuded allelochemicals of cumin seeds. Furthermore, all genotypes showed the average germination percentage to be less than the control samples. They could significantly reduce total species richness and diversity in their surroundings. Weed suppressive percentage of cumin genotypes in the field experiments was positively correlated with inhibition percentage of radicle growth in the laboratory. Water stress increases the allelopathic effects of cumin accessions in laboratory screening. Classification based on principle component method indicated that cumin genotypes were categorized into two clusters in both moisture regimes. Despite having stress factors, only the genotypes 13CGOGK₁, 35CSESH₁, 65CEAAS, 68CKERF₂, 75CYAAR₂, and 84CKRTJ₂ remained in a group with strong allelopathic activity. According to these results, there is the significant diversity for allelopathic strength in the Iranian cumin germplasm, which can be useful in cumin breeding for weed suppression.     

Interval sampling methods in Zagros forests using GIS

In this study, for accuracy and cost an optimal inventory method was examined and introduced to obtain information about Zagros forests, Iran. For this purpose,three distance sampling methods(compound, order distance and random-pairs) in 5 inventory networks(100 m × 100 m, 100 m × 150 m, 100 m × 200 m,150 m × 150 m, 200 m × 200 m) were implemented in GIS environment, and the related statistical analyses were carried out. Average tree density and canopy cover in hectare with 100% inventory were compared to each other.All the studied methods were implemented in 30 inventory points, and the implementation time of each was recorded.According to the results, the best inventory methods for estimating density and canopy cover were compound150 m × 150 m and 100 m × 100 m methods, respectively. The minimum amount of product inventory time per second(T), and(E%)2 square percent of inventory error of sampling for the compound 150 m × 150 m method regarding density in hectare was 691.8, and for the compound 100 m × 100 m method regarding canopy of 12,089 ha. It can be concluded that compound method is the best for estimating density and canopy features of the forests area.     

Study Potential of Indigenous <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> and <Emphasis Type="Italic">Bacillus subtilis</Emphasis> in Bioremediation of Diesel-Contaminated Water

Petroleum products which are used in a wide variety of industries as energy sources and raw materials have become a major concern in pollution of terrestrial and marine environments. The purpose of this study was to assess the potential of indigenous microbial isolates for degradation of diesel fuel. Two most proficient bacterial strains among five isolated strains from polluted soil of an industrial refinery were studied. The isolates then were identified as Pseudomonas aeruginosa and Bacillus subtilis using biochemical tests and 16S rRNA gene sequence analyses. P. aeruginosa showed higher biodegradation efficiency than B. subtilis in shaking flask containing diesel-contaminated water. P. aeruginosa and B. subtilis degraded about 87 and 75% of total hydrocarbons, respectively, in flasks containing 2% diesel and 98% water. The biodegradation efficiency of the isolates decreased as diesel contamination increased from 2 to 5%. The isolates showed significantly higher efficiency on degradation of short-chain hydrocarbons in 20 days, i.e., by using P. aeruginosa, removal efficiency of C₁₀ hydrocarbons was near 90%, while about 69% of C₂₀₊ hydrocarbons and 47% of aromatic hydrocarbons were removed. Therefore, the isolates showed high capability in biodegradation of diesel contamination of the refinery.     

Effects of mycorrhiza inoculation on cucumber growth irrigated with saline water

This experiment was conducted as a factorial based on complete randomized design (CRD) to study the effects of mycorrhiza inoculation density on cucumber cv. Super N3 irrigated with different salinity sodium chloride (NaCl) levels. Treatments were mycorrhiza inoculations; M1 (non mycorrhizal plant), M2 and M3 (mycorrhiza inoculations with 1000 and 2000 spores) and saline water was provided by S1, S2, S3, and S4 (control, 50, 75, and 100 mM NaCl) with 4 replications. The results showed that saline water reduced root, shoot, and fruit weights, and increased proline and electrolyte leakage. Photosynthesis rate, stomata and mesophyll conductance significantly decreased with increased NaCl concentrations. Mycorrhiza inoculation with 2000 spores increased fruit fresh and dry weights, proline and electrolyte leakage, and both mycorrhiza inoculations increased root and shoot dry weights, photosynthesis and stomata conductance. Root volume increased by mycorrhiza inoculation with 2000 spores under non-stress condition, and root length was stimulated by both mycorrhiza inoculations at all saline water levels. Fruit fresh and dry weights were enhanced by mycorrhiza inoculation with 1000 spores at all saline water levels. Photosynthesis rate was reduced by saline water stress and mycorrhiza inoculation stimulated photosynthesis rate. Mycorrhiza inoculation with 2000 spores increased transpiration under saline and non-saline conditions. Proline content of cucumber leaves increased under saline water application. Electrolyte leakage increased by saline water and mycorrhiza inoculation could not improve it. Both mycorrhiza inoculations (1000 and 2000 spores) at all salinity levels, and mycorrhiza inoculation with 1000 spores at 100 mM NaCl enhanced fruit weight, photosynthesis, and proline content of the cucumber leaves.     

Chemical composition of oleo-gum-resin from Ferula gummosa

The chemical composition of oleo-gum-resin from Ferula gummosa collected in the northern part of Iran has been studied. The fraction of oleo-gum-resin soluble in ethanol (ca 67 wt.%) is composed by three major fractions: (i) monoterpenes and monoterpenoids (ca 15 wt.% fraction), (ii) sesquiterpenes and sesquiterpenoids (ca 30 wt.%) and (iii) triterpenes and triterpenoids (ca 55 wt.%). The major families of terpenes and terpenoids were identified employing gas chromatography coupled with mass spectrometry detector (GC-MS). Almost 25 wt.% of oleo-gum-resin was insoluble in ethanol and, according to wet chemistry analyses, assigned to arabinogalactane structurally associated with protein complex (AGP). This arabinogalactan possessed the molecular weight of ca 30 kDa, as revealed by size exclusion chromatography, and the main backbone was constituted by β-(1 → 3)/β-(1 → 3,6)-linked d-galactopyranosyl residues ramified predominantly by terminal α-l-arabinofuranosyl and β-d-glucuronopyranosyl residues, as assessed by 1D/2D ¹H NMR.     

Resistance to <Emphasis Type="Italic">Meloidogyne incognita</Emphasis> expresses a hypersensitive-like response in <Emphasis Type="Italic">Coffea arabica</Emphasis>

Root-knot nematodes (RKN) are obligate parasite species of the genus Meloidogyne that cause great losses in Arabica coffee (Coffea arabica L.) plantations. Identification of resistant genotypes would facilitate the improvement of coffee varieties aiming at an environmental friendly and costless nematode control. In this work, the C. arabica genotype ‘UFV 408-28’ was found to be resistant to the most destructive RKN species M. incognita. Pathogenicity assays indicated that the highly aggressive populations of M. incognita races 1, 2 and 3 were not able to successfully reproduce on ‘UFV 408-28’ roots and displayed a low gall index (GI = 2). An average reduction of 87% reduction of the M. incognita population was observed on ‘UFV 408-28’ when compared to the susceptible cultivar ‘IAC 15’. By contrast, ‘UFV 408-28’ was susceptible to the related species M. exigua and M. paranaensis (GI = 5 and 4, respectively). Histological observations performed on sections of UFV408-28 roots infected with M. incognita race 1 showed that nematode infection could be blocked right after penetration or during migration and establishment stages, at 6 days, 7 days and 8 days after infection (DAI). Fluorescence and bright field microscopy observations showed that root cells surrounding the nematodes exhibited HR-like features such as accumulation of phenolic compounds and a necrotic cell aspect. In the susceptible ‘IAC 15’ roots, 6 DAI, feeding sites contained giant cells with a dense cytoplasm. Necrotic cells were never observed throughout the entire infection cycle. The HR-like phenotype observed in the ‘UFV 408-28’—M. incognita interaction suggests that the coffee resistance may be mediated by a R-gene based immunity system and may therefore provide new insights for understanding the molecular basis of RKN resistance in perennial crops.     

Investigation of physico-chemical properties and antioxidant activity of twenty Iranian pomegranate (Punica granatum L.) cultivars

Pomegranate is one of the native fruits of Iran which contains high genetic resources, but there are insufficient information regarding properties of the fruit. The objective of the present study was to investigate the physcio-chemical characteristics and antioxidant activity of twenty pomegranate cultivars grown in Iran. This study showed that there were significant differences among the cultivars in all measured factors except the length/diameter ratio of fruit. The fruit weight, skin percentage, aril percentage and juice percentage were within the range of 196.89–315.28 g, 32.28–59.82%, 37.59–65% and 26.95–46.55%, respectively. The total soluble solids content varied from 11.37 (°Brix) to 15.07 (°Brix), pH values from 3.16 to 4.09, titratable acidity content from 0.33 g 100 g⁻¹ to 2.44 g 100 g⁻¹ and total sugars content from 13.23 g 100 g⁻¹ to 21.72 g 100 g⁻¹. The results also showed that the values of ascorbic acid ranged from 9.91 mg 100 g⁻¹ to 20.92 mg 100 g⁻¹. The total anthocyanins content was observed in pomegranate cultivars between 5.56  mg 100 g⁻¹ and 30.11 mg 100 g⁻¹. The level of total phenolics was varied from 295.79 mg 100 g⁻¹ to 985.37 mg 100 g⁻¹. The antioxidant activity of pomegranate cultivars was found between 15.59 and 40.72%. These data demonstrated that the cultivar was the main parameter which influences the physico-chemical properties and antioxidant activity in pomegranates.     

Molecular characterization of a Squalene epoxidase gene in dermatophyte pathogen Trichophyton tonsurans

BACKGROUND: Trichophyton tonsurans is one of the dermatophyte fungi which invades the skin and hair of human. Several properties of this fungus have been investigated so far. However a few studies were carried out in the field of molecular biology of this fungus. In the present study, we tried to identify the Squalene epoxidase gene which is related to synthesis of ergosterol in this fungus. METHODS: Pairs of 23 and 24 nucleotides primers were designed from highly conserved regions of the similar genes in other fungi. Mentioned primers were utilized in PCR by using isolated genomic DNA of T. tonsurans whereas the PCR fragments were then sequenced. RESULTS AND CONCLUSION: Nucleotides (n = 558) have been sequenced from this new gene which encodes a polypeptide with 186 amino acids. Sequences comparison in gene data banks (NCBI, NIH) for this part of DNA and its deduced amino acid revealed significant homology with members of the eukaryotic Squalene epoxidase.     

Wastewater Irrigation Effect on Soil,Crop and Environment: a Pilot Scale Study at Irbid,Jordan

An investigation was carried out at pilot scale to test the feasibility of using the effluent of a rotating biological contactors (RBC) unit treating wastewater generated from a university campus. The objective of the study was to cerefully monitor the impact of wastewater irrigation on the soil, percolating water, crop growth and the pathogenic condition within the immediate vicinity of wastewater application. Experimental plots with three crops: alfalfa, radish and tomato were irrigated with fresh and waste waters. The irrigation water was applied by sprinklers. Each crop was given two sub-treatments: with fertilizer and without fertilizer. The physical and chemical properties of the soil, the crop yields, and subsurface drainage were measured. In most of the cases, the yields resulted from the uses of wastewater with fertilizer were compatible with those of the uses of freshwater with fertilizer. The washings of tomato fruits grown with wastewater were analyzed for fecal coliforms. It appeared that the fruit skins were free of viable fecal coliforms 24 hours after the wastewater application. Subsurface drainage analyses did not show any alarming levels of constituents irrespective of the source of the water: wastewater or freshwater. The wastewater irrigation applied for a season had no significant effect on a silty loam soil. With wastewater irrigation, slught changes in the soil porosity and salinity were observed.     

Fabrication and characterization of nanofibers based on poly(lactic acid)/chitosan blends by electrospinning and their functionalization with phospholipase A1

In this work, electrospinning of poly(lactic acid) (PLA), chitosan and their blends has been investigated, and nanofibers with a diameter ranging from 90 nm to 1.9 microns were produced and used as carriers for immobilization of the phospholipase A1. A strong influence of chitosan (CS) and the solvent trifluoroacetic acid (TFA) on the morphology, distribution of the nanofibers diameter and on their hydrophobicity was observed. The yield of phospholipase A1 (PLA1) on non-woven fibers was evaluated using the method of Bradford. Their activities and their reutilisability were assessed titrimetrically using soybean lecithin as substrate. The results showed that the degree of immobilization on the non-woven fibers of pure PLA and mixtures PLA/CS4 and PLA/SC6 are 73, 54, 45 % respectively and can be reused up to 4 cycles without significant loss of enzyme activity. Moreover, a remarkable improvement of the activity of phospholipase A1 on non-woven based on pure PLA fibers was observed, indicating that most of the enzymes were probably in their active form.