Effects of Bentonite Application and Urea Fertilization Time on Growth,Development and Nitrate Accumulation in Spinach (Spinacia oleraceae L.)

Under excessive application of nitrogen fertilizer, vegetables can accumulate high levels of nitrate in their vegetative body and, when consumed by living organisms, pose serious health-related risks for humans. Regarding such problems, it is necessary to minimize the accumulation of nitrate in leafy vegetables. Therefore, a pot experiment was conducted to evaluate bentonite levels (0, 20, 40, 60, 80 g/kg soil) application and urea fertilization times (25, 50, 75 days after sowing; at the rate of 0.2 g per pot) on the growth, development and nitrate accumulation of spinach. Results showed that urea fertilization on 25 days after sowing date had the highest effect on the quality, while application of 60 gr bentonite had the highest effect on the improvement of growth parameters of spinach. The lowest nitrate and nitrite accumulation rate was observed at urea fertilization on 50 days after planting and lack of bentonite application, whereas the lowest oxalic acid content was obtained at urea fertilization on 25 days after planting in a soil without bentonite application. The results showed that implementing an appropriate rate of bentonite and urea fertilization times may bring about favorable results for spinach production.     

Fruit Quality and Nitrogen,Potassium, and Calcium Content of Apple as Influenced by Nitrate: Ammonium Ratios in Tree Nutrition

Evaluations of fruit quality and nitrogen, potassium, and calcium concentration of apple (Malus domestica Borkh. cvs. Gala and Golab) grown with five treatments of NO₃^?:NH₄⁺ ratios were made in pot culture. The concentrations of NO₃^?:NH₄⁺ ratios were 2.5:0.1, 6:1, 6:0.7, 6:0.5, 6:0.3 meq L^?1. Fruit size, percent dry matter, total dissolved solids, total acidity, or juice pH was not affected by increased ammonium in the ratio. Firmness decreased as the proportion of NH₄⁺ increased. Gala and Golab differed in some of these parameters. Concentrations of N and K increased as NH₄⁺ increased, whereas Ca had no trend or decreased. Generally, the treatment of 2.5:0.1 produced fruits with lower N but higher K and Ca concentrations than the other treatments. This research showed that some parameters such as fruit weight, length, and diameter, juice pH, and dry matter were not affected significantly by NH₄⁺ concentration whereas composition was affected.     

Preparation of glucosamine from exoskeleton of shrimp and predicting production yield by response surface methodology

Chitin was prepared from Persian Gulf shrimp (Metapenaeus monoceros), and then, the obtained chitin was hydrolyzed by hydrochloric acid solutions. The production yield of glucosamine hydrochloride from chitin was optimized, and the effect of three factors (acid concentration, acid to chitin ratio, and reaction time) was investigated. A Box-Behnken design by Minitab software created 12 reactions with different conditions. Each reaction was performed in two replicates. Response surface methodology was used for predicting the glucosamine preparation. The optimum conditions for glucosamine hydrochloride preparation were 30 and 37% hydrochloric acid, 9:1 (v/w) acid solution to solid ratio, and 4 h of reaction time. Time ratio and time acid concentrations were the effective factors on the yield.     

Protective role of selenium on cucumber (Cucumis sativus L.) exposed to cadmium and lead stress during reproductive stage role of selenium on heavy metals stress

The present study aimed to investigate the effect of selenium on flowering indices, sex determination of flowers, and yield of cucumber plant under heavy metal stress conditions. Treatments consisted of selenium (0, 4, 6, 8 mgL^?1) and heavy metals of cadmium (0, 20, 25 µM) and lead (0, 60, 100 µM), which were applied in three stages during the experiment period. The results of this study showed that the stress of heavy metals with a negative effect on flowering indices resulted in delayed flowering and changing flower’s sex toward male flowers. Furthermore, delayed fruiting and significant decreases in fruit growth indices and total yield was observed in plants treated with cadmium and lead. Adding selenium to the culture medium resulted in accelerated flowering (reducing the time and number of nodes needed until the first flower emerges), the emergence of more male flowers, increased the ratio of the number of female flowers to male flowers in plants under stress, and the highest effect of this element was observed at the concentration 6?mg/L. Based on this results, the application of 4and 6mg/L selenium in stress and non-stress conditions enhanced fruiting (a significant reduction in the time required from cultivation to fertilize the first flower and the formation of fruit in lower nodes) and significantly increased the number of fruits, fruit length and diameter, single fruit weight and total yield, and the greatest effect of this element was observed in 6?mg/L concentration. The results of this study showed that selenium has a positive effect on control of stress conditions and improvement of flowering indices and total yield in cucumber plant under the stress of heavy elements of lead and cadmium.     

Symptoms and fungi associated with elm trees decline in Iran

Elm (Ulmus, Ulmaceae) is one of the most popular and important trees in urban and landscape areas in Iran. A severe decline of elm trees has recently been observed in some areas of Kerman and Shiraz cities. However, the identity of the causal agents has not yet been investigated. The purpose of this study, carried out in the years 2012–2014, was to isolate and identify fungal trunk pathogens associated with decline symptoms observed in elm trees. Samples were collected from trunks and branches of trees showing various disease symptoms and internal wood lesions. Fungal isolations were made from discolored or decayed wood tissue. In Kerman some elm trees were attacked by the beetle Aeolesthes sarta; therefore, samples were also collected from larvae and adults of beetles associated with trees showing wood damage. Fungal isolates were identified by morphological, cultural and molecular characteristics. Thirteen fungal species, Phaeoacremonium (P.) minimum, P. parasiticum, P. sicilianum, P. alvesii, P. fraxinopennsylvanicum, Spencermartinsia viticola, Dothiorella (Do.) sarmentorum, Neoscytalidium hyalinum, Diatrype (Di.) whitmanensis, Cosmospora viridescens, Phoma (Pho.) herbarum, Phellinus (Phe.) tuberculosus and Inonotus levis were identified. Phaeoacremonium parasiticum was the only species isolated from both larvae and adult beetles. Pathogenicity trials were performed on detached shoots of elm under greenhouse conditions. Dothiorella sarmentorum was the most virulent species based on the length of wood necrosis. This study is the first report of P. sicilianum, C. viridescens and Phe. tuberculosus in Iran. In addition, most of the isolated species are reported for the first time on elm trees in the world.     

Estimating soil organic carbon from soil reflectance: a review

Soil organic carbon (SOC) concentration is a useful soil property with which to guide agricultural applications of chemical inputs. To enable this, simple, accurate, rapid and inexpensive methods are needed to produce maps of surface SOC concentrations. Researchers have investigated estimates of soil surface properties from remotely sensed information as a means of rapidly quantifying and monitoring some surface soil properties, such as SOC. The objective of this paper is to review the potential and limitations of remotely sensed data for mapping and evaluating SOC. Several statistical methods including simple regression models, the ‘soil line’ approach, principal component analysis and geostatistics have been applied to data to investigate the accuracy of such estimates. A review of the literature shows that predictive equations are not universal and require new regression models for every scene. An important benefit of remotely sensed data is to suggest a sampling strategy that can lead to improved representation of spatial heterogeneity in SOC.     

Disseminated Mycobacterium avium subsp. hominissuis infection and ascites in an FIV-positive cat

A domestic shorthair cat was presented to the Veterinary Teaching Hospital at The University of the West Indies with a history of anorexia, ataxia, and lethargy. On physical examination, moderate abdominal distension and a palpable abdominal fluid wave were noted. Dark yellow, cloudy fluid was collected via abdominocentesis. Fluid analysis indicated that the effusion was a transudate containing low numbers of macrophages and occasional neutrophils. Some of the macrophages contained rod-shaped nonstaining structures of variable length (2-4 um). These structures were also seen extracellularly in low numbers. The morphology of the structures was suggestive of Mycobacterium. The cat's condition continued to deteriorate, and it died within a few hours of being admitted. Further diagnostic tests revealed feline immunodeficiency virus (FIV) infection with concurrent Mycobacterium avium subsp hominissuis infection. To the authors’ knowledge, this is the first reported case of nontubercular mycobacterial-related ascites in a cat.     

Grain Yield and Qualitative of Rapeseed Genotypes Change in Response to Exogenous Application of Salicylic Acid and Planting Density

Gesunde Pflanzen - A factorial split-plot experiment (2015–17) was carried out in a randomized complete block design with three replications at Karaj, Iran, to investigate...     

Polymorphisms in GDF9 and BMP15 Associated with Fertility and Ovulation Rate in Moghani and Ghezel Sheep in Iran

The genetic base of fertility and ovulation rate in Moghani and Ghezel sheep in northwestern Iran and northeastern Turkey is important because of their fat‐tailed meat and carpet quality wool. The genes encoding bone morphogenetic (BM) protein 15 and growth differentiation (GD) factor 9, respectively BMP15 and GDF9 have been shown to affect female productivity in domesticated sheep. Recently, numerous investigations have been performed on a variety of breeds to determine the association between mutations in these genes and fertility. Thus, in this study, we assessed such mutations in the Moghani and Ghezel breeds using polymerase chain reaction (PCR)‐based restriction fragment length polymorphism (RFLP) with appropriate enzymes. Our data were similar to those of the previous studies showing that the genotypes were heterozygous for GD (G →A) and BM (C →T) mutations. These heterozygous genotypes resulted in higher ovulation rates, illustrating that one copy of each of the BMP15 and GDF9 mutations had equivalent effects on the ovulation rate. We demonstrate for the first time that the BM variant may not be sufficient on its own for infertility. In addition, although the previous studies have shown no notable relationship between the GD variant, known as the non‐effecting mutation and sterility, we report that this mutation has an important role in the Moghani and Ghezel breeds.     

Treatment of Waters Contaminated by Phenol and Cresols in Circulating Packed Bed Bioreactors—Biodegradation and Toxicity Evaluations

Water, Air, & Soil Pollution - Specific (nitrifying, denitrifying, and methanogenic) microbial activities were measured in simplified down-flow lab-scale columns simulating subsurface...