Effects of plant residue management on soil properties,surface runoff,and soil loss under rainfall simulation in a semi-arid region in Iran

A 5-year field study was conducted on the effect of plant residue management on soil erosion, runoff, bulk density, penetration resistance, and organic carbon. There were three treatments: burning residues on field (BR), returning residues unto the soil surface after harvesting (TR), and removing residues from soil surface (RR) (control treatment). At the end of the 5-year treatment, a rainfall simulation at 90?mm?h^?1 was applied to each plot. After rainfall simulation started, the runoff volume and soil loss amount in samples were collected at four sampling times. The results showed that the runoff volume for BR (from 145.5?±?12.2 to 190.0?±?11.8?mL) differed significantly (p?≤?0.01) from that of RR (from 32.3?±?5.5 to 67.5?±?11.1?mL) and TR (from 10.0?±?0.7 to 16.7?±?3.3?mL). A significant difference (p?≤?0.01) was also observed between RR and TR regarding runoff volume and soil loss amount in different sampling times, except for the first sampling time (2–4?min). The runoff volume in BR and TR was 215% higher and 294% lower than that of the control (RR), respectively. As compared to the control (RR), soil loss decreased by 96.5% in TR but increased by 192% in BR. The BR increased soil bulk density and penetration resistance by 4.9% and 12.4%, whereas TR reduced them by 2.1% and 15.8%, respectively, as compared to the control (RR). The results indicated that the highest (0.35) and lowest (0.03) runoff coefficients were obtained for BR and TR treatments, respectively. It is concluded that returning plant residues to soil is the best residue management practice in decreasing soil runoff volume and controlling soil erosion in semi-arid regions.     

Optimizing phosphorus use in sustainable maize cropping via mycorrhizal inoculation

More details have yet to be indicated on the interactions between arbuscular mycorrhizal (AM) fungi and phosphorus (P) chemical fertilization under field conditions. Accordingly, the objectives were to: (1) evaluate the combined effects of mycorrhizal fungi and chemical P fertilization on maize yield, yield components, and nutrient uptake and (2) indicate the optimum rate of P chemical fertilization (P₁, P₂, P₃) with the use of mycorrhizal fungi (Glomus intraradices and G. mosseae). A factorial experiment using randomized complete blocks with three replicates, conducted at the Research Station of the Faculty of Agriculture, Islamic Azad University, Tabriz branch, Iran. Results indicated the significant effect of P, AM fungi, and their interaction on most of the measured traits. Grain yield (7909.3 kg/ha), maize nutrient content of P (0.39%), zinc (Zn) (42.1 mg/kg), iron (Fe) (68.3 mg/kg), and the colonization rate (47.5%) were all the highest by the interaction of G intraradices × P₂.     

The Potential of Green Manure Mixtures to Provide Nutrients to a Subsequent Lettuce Crop

The objectives of this greenhouse experiment were to quantify the benefits of green manure (GM) diversity and to assess effect of GM on a succeeding lettuce crop. Species included barley (B), field pea (P), sunn hemp (S), and buckwheat (U). Treatments included single plantings of B and P and mixtures of B and P (BP), B, P, and S (BPS), and B, P, S, and U (BPSU). The pea GM had the highest shoot concentration of potassium, calcium, magnesium, manganese, zinc, and iron. Roots had higher concentrations of nutrients than shoots. Accumulation of nutrients in legumes was higher than in barley. The CO₂ flux from the soil suggests that the most intensive mineralization period occurred within two weeks after incorporation of GMs. The mixtures and single planting of P mixtures had a significant benefit over single planting of B regarding fresh and dry weight of the lettuce.     

How Nitrogen and Zinc Levels Affect Seed Yield,Quality, and Nutrient Uptake of Canola Irrigated with Saline and Ultra-Saline Water

In order to investigate the effects of nitrogen (N) and zinc (Zn) fertilizers on seed yield, oil percentage, glucosinolate content, and nutrient uptake of canola (Brassica napus L. cv. Okapi), irrigated with saline and ultra-saline water, field experiments were conducted in Agriculture Research Centre of East Azarbaijan, Iran, during three consecutive years: 2011, 2012, and 2013. The experiments were carried out based on randomized complete block design arranged in factorial with three replications. The experimental treatments included N rates at three levels (0, 50, and 100 kg ha^?1), Zn rates at three levels (0, 5, and 10 kg ha^?1), and saline water at two levels (8 and 16 dS m^?1 as saline and ultra-saline water). According to the results, N and Zn application had a significant effect on the plant height, pod number per plant, and seed yield. However, the value of these traits decreased as a result of the higher salinity level (from 8 to 16 dS m^?1). From the results, the glucosinolate content was not affected by N or Zn fertilization, whereas, salinity increased the glucosinolate content from 27.51% to 30.06% when saline water and ultra-saline water were applied, respectively. In addition, the effect of ultra-saline water on the decrease in the N, phosphorous, potassium, and calcium uptake and the increase in the sodium and chlorine accumulation in canola seed was significant. However, Zn application could diminish adverse effects of salinity on phosphorus uptake. For instance, under ultra-saline water conditions, application of 10 kg ha^?1 Zn increased the seed phosphorus content compared with control treatment. In general, it seems that nutrients’ supply, especially N and Zn, can be considered as an effective solution to diminish adverse effects of salinity.     

Genetic correlations between growth and reproductive traits in Zandi sheep

For the first time, the current study reports the genetic and phenotypic correlations between growth and reproductive traits in Zandi sheep. The data were comprised of 4,309 records of lamb growth traits from 1,378 dams and 273 sires plus 2,588 records of reproductive traits from 577 ewes. These data were extracted from available performance records at Khojir Breeding Station of Zandi sheep in Tehran, Iran, from 1993 to 2008. Correlations were estimated from two animal models in a bivariate analysis using restricted maximum likelihood procedure between lamb growth traits [birth weight (BW), weaning weight at 3 months of age (WW), as well as six-month weight (6 MW)] and ewe reproductive traits [litter size at birth (LSB), litter size at weaning (LSW), total litter weight at birth (TLWB), and total litter weight at weaning (TLWW)]. The genetic correlations between BW and reproductive traits varied from low to high ranges from 0.10 for BW–LSB to 0.86 for BW–TLWB. WW was moderately (0.37) to highly (0.96) correlated with all the reproductive traits. Moreover, the genetic correlations were observed between 6 MW and reproductive traits, varied from 0.19 to 0.95. Relationships between growth and reproductive traits ranged from 0.01 for BW–LSW to 0.28 for BW–TLWB in phenotypic effects. Results indicated that selection to improve WW would have high effect on genetic response in TLWW, and also, these results could be effective for all of the reproductive traits in Zandi sheep.     

Prevalence of obesity, food choices and socio-economic status: a cross-sectional study in the north-west of Iran

AIM: To document the epidemiological features and influencing factors of obesity in the north-west of Iran, to provide baseline information for setting up a regional population-based centre to control and prevent obesity-related disorders in the area. METHODS: In this cross-sectional study, a total of 300 subjects were selected/studied in Tabriz, one of the major cities in Iran. Data on basic characteristics, anthropometric measurements, dietary assessment and physical activity were collected. Obesity was defined as body mass index > or =30 kg m(-2) for both women and men. RESULTS: Total prevalence of obesity in the area was 22.4% (95% confidence interval (CI): 18.0-27.6). The prevalence of obesity was 24% (95% CI: 18.5-31.4) for women and 18% (95% CI: 12.5-25.6) for men. For both women and men obesity prevalence showed a positive association with age (P<0.001), while there was a negative correlation of obesity with education and income (P<0.001). Fruit consumption decreased the risk of obesity in both women and men (odds ratio (OR)=0.60, 95% CI: 0.49-0.71 vs. OR=0.62, 95% CI: 0.51-0.74, respectively). The same significant pattern was observed for the consumption of green vegetables (OR=0.71, 95% CI: 0.57-0.63 vs. OR=0.86, 95% CI: 0.77-0.98 for women and men, respectively), legumes (OR=0.70, 95% CI: 0.59-0.84 vs. OR=0.78, 95% CI: 0.66-0.91 for women and men, respectively) and dairy products (OR=0.73, 95% CI: 0.61-0.91 vs. OR=0.77, 95% CI: 0.63-0.93 for women and men, respectively). CONCLUSIONS: Our study showed that educational attainment, higher income and consumption of certain food groups (i.e. vegetables, fruits, legumes and dairy products) may decrease the risk of obesity. Our findings also indicate the crucial necessity of establishing a population-based centre for obesity in the area. The essential information is now achieved to propose to local health authorities to act accordingly. However, more population-based investigations on dietary choices are needed to develop effective preventive strategies to control overweight and obesity disorders in different regions.     

The Effect of Ascorbic Acid and Garlic Administration on Lead-Induced Apoptosis in Rat Offspring's Eye Retina

Introduction: Lead toxicity induces retinal cell apoptosis. Vitamin C and garlic may decrease lead-induced apoptosis. This study was undertaken to investigate vitamin C and garlic protective effects on lead-induced apoptosis in eye retina. Methods: Pregnant Wistar rats (n = 72) were divided randomly into 9 groups: (L) treated rats with lead acetate in drinking water and (L+AA) with leaded water and vitamin C intraperitoneally;(L+G), the rats received leaded-water and garlic juice via gavage; (L+AA+G) treated rats with leaded water, ascorbic acid, and garlic juice, (AA) with ascorbic acid, and (G) with garlic juice; (AA+G) treated rats with vitamin C and garlic juice and (Sh) with tap water plus normal hydrogen chloride (HCl) and glucose; normal (N). After 21-day lactation, blood lead level (BLL) in rats was measured, and then their offspring and the rat offspring''s eyes were removed and processed for using TUNEL method. TUNEL positive cells in the eye retina were counted and all groups were compared. Results: BLL increased in L group compared to the control groups and decreased significantly in L + G, L + AA, and L+ AA + G groups compared to L group (P<0.05). TUNELL positive cell number in eye retina significantly increased in L group compared to control groups (P<0.05) and decreased in L+ G, L+ AA, and L+AA + G groups compared to L group (P<0.05). Conclusion: Garlic juice and ascorbic acid administration during pregnancy and lactation may protect lead-induced apoptosis in rat offspring''s eye retina. Key Words: Lead, Garlic, Ascorbic acid, Apoptosis, Retina     

pH sensitive and controlled release system based on cellulose nanofibers-poly vinyl alcohol hydrogels for cisplatin delivery

Delivery of chemotherapy drugs, such as cisplatin, with controlled manner is a significant area of research in cancer treatment. The main purpose of this study was to investigate the in-vitro release of cisplatin from pH sensitive and controlled release hydrogels based on cellulose nanofibers (CNFs) and poly(vinyl alcohol) (PVA). Various hydrogels with different amounts of CNFs were prepared. This novel drug delivery system was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses. By in-vitro experiments the influence of CNFs contents and pH of the release media on the release rate of the drug were investigated. According to the results, the hydrogel containing 1 wt% CNFs in the release media with the pH of 7.4, efficiently sustained the drug release and so can cause to the reduction of side effects of drug. By fitting the experimental data with various kinetic models it was concluded that the release mechanism is best fitted by Korsmeyer-Peppas kinetic model suggesting the diffusion controlled release mechanism. The prepared hydrogel system is suitable for delivery of cisplatin in the small intestine with a controlled manner.     

Culture‐based methods using low‐temperature incubation revealed cold‐adapted fungal endophytes from semiarid forests

Fungal endophytes are an important part of the plant microbiome and participate in maintaining the stability of ecosystems. Culture‐based methods are frequently considered in studying fungal communities because of their advantages in providing cultures for further experiments and their low cost. In comparison with next‐generation sequencing methods, their ability to assess fungal diversity is questionable. Here, we show how using two different incubation temperatures can improve the yield of fungal endophytes by culture‐based methods. Diversity, organ preference and spatiotemporal variability of endophytic fungal communities living within Quercus brantii L. were investigated using two different incubation temperatures. To test the effects of using low‐temperature incubation on diversity estimations, twigs and leaves of Quercus brantii were incubated under 25°C and 4°C conditions. Isolation rate and Hill's series of diversity were calculated for each sample. Model‐based analysis was used to evaluate the effects of (a) incubation temperature, (b) organ type and (c) spatiotemporal variations on fungal isolation rate, fungal diversity and community composition. Our results showed a strong organ specificity and temporal dynamics among endophytic fungal communities, but the location of the forest stand had only a limited effect on fungal community composition. Low‐temperature incubation enabled us to improve culture‐based methods by discovering the diversity of cold‐adapted fungal endophytes and a significantly different part of the endophytic communities that is usually missed by customary culturing temperature. The isolation of cold‐adapted endophytes from a semiarid environment opens a new window to further studies on this kind of fungi in such ecosystems.     

Saffron Daughter Corms Formation,Nitrogen and Phosphorous Uptake in Response to Low Planting Density,Sampling Rounds,Vermicompost and Mineral Fertilizers

Higher planting densities increase flower yield of saffron during the initial years; however, increase in population may have a negative effect on daughter corms, through increasing competition for nutrients. Accordingly, lower densities result in more desirable daughter corms for future planting. To investigate the effect of planting density, vermicompost and mineral fertilizers on daughter corms formation, and nitrogen (N) and phosphorus (P) content in the corms during different phenological stages, a three-year field experiment was conducted as factorial-split layout based on randomized complete block design with three replications, at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran. The experiment consisted of 12 main plots [planting density (30, 60, 90 and 120 corms m^?2) × fertilizer sources (vermicompost 10.2 t ha^?1, mineral fertilizer including N 225 kg ha^?1 + P 129.08 kg ha^?1 and control)] and 15 subplots (15 sampling rounds; during the first, second and third growing seasons). During all stages of sampling, N and P content in large-sized daughter corms was significantly higher compared with middle and large-sized daughter corms. Application of vermicompost significantly increased the number, weight, N and P contents of medium and large daughter corms per plant than mineral fertilizer. Increase in plating density caused a significant reduction in number, weight, N and P content in the medium and large sized daughter corms per plant. Overall, the results suggest that lower densities and vermicompost application should be scheduled in mother corms production programs.