Inoculation of ‘Golden Delicious’ Apple Trees on M9 Rootstock with Azotobacter Improves Nutrient Uptake and Growth Indices

ABSTRACT

Roots of young ‘Golden Delicious’ apple on M9 rootstock were inoculated with four strains of Azotobacter chroococcum, which were isolated from various soils. Effects of these strains in combination with different levels of nitrogen (N) fertilizer and compost on plant growth and nutrient uptake were studied over two seasons. Therefore, a factorial arrangement included four strains of A. chroococcum, two levels of N-fertilizer (0 and 35 mg N kg^?1soil of ammonium nitrate) and two levels of compost (0 and 12 g kg^?1 soil of air-dried vermicompost). Among the four strains, AFA₁₄₆ was the most beneficial strain, as it increased leaf area, leaf potassium (K), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and boron (B) uptake and root N, phosphorus (P), potassium (K), Mn, and Zn. The combination of AFA₁₄₆ strain, compost and N fertilizer increased leaf uptake of Ca, Mg, Fe, Mn, Zn, and B, and root uptake of P, K, Ca, Mg, Mn, and copper (Cu), and root dry weight.     

Attribute selection and model evaluation for the maternal and paternal imprinted genes in bovine (Bos Taurus) using supervised machine learning algorithms

Imprinted genes display biased expression of paternal and maternal alleles in mammals. They are marked through epigenetic process during gametogenesis. Characterization of imprinted genes has expanded our understanding of the regulation and function of genes. In the current study, 22 experimentally validated imprinted genes in bovine (Bos Taurus) were analysed. Several supervised machine learning algorithms and attribute weighting methods were used to find characteristics of different types of imprinted genes and suggest a classification method for finding maternally and paternally expressed genes in bovine. For assessing the best model and comparing attributes in other organisms, we have also conducted a comparative analysis for human and sheep imprinted genes. According to the results of the present study, GC contents 10 and 100 kb upstream, Gly and Gln amino acids, Ile/ATC codon usage, LINE and SINE in 100kbup and length of first intron were significantly different between the maternal and paternal genes in cattle. Considering all species together, we found that GC content 100 kb up, LINE 100 kb up and the frequency of amino acids like Gly, Gln and Met were the most important attributes for identifying the paternal and maternal imprinted genes. These findings could imply conservation pattern in the attributes among these species.     

Effect of vitamin C supplementation on postprandial oxidative stress and lipid profile in type 2 diabetic patients

Diabetes mellitus is one of the most wide spread endocrine disorders and an important developing health problem in the world. Cardiovascular disease is a common complication of type 2 diabetes. Several risk factors for coronary heart disease cosegregate in type 2 diabetes, including hyperglycemia, hyperlipaemia, increases production of free radical and decrease in antioxidant defense system. In this study we evaluated the effect of vitamin C supplementation on fasting and postprandial oxidative stress and lipid profile in type 2 diabetic patients. 30 patients with type 2 diabetes from Nader Kazemi Clinic, Shiraz, Iran were randomly divided into 2 groups; vitamin C treatment group (1000 mg d(-1)) and placebo group from May to September 2010. Fasting and postprandial lipid profile and Malondialdehyde (MDA) level were measured at the beginning of the study and after six weeks of supplementation. Data analysis was carried out using Mann-Whitney U test with p < 0.05 being significant by SPSS software version 16.The result of the study showed a significantly decrease in fasting (p = 0.006) and postprandial MDA (p < 0.001) in vitamin C group compare to placebo group but not in lipid profile. This study suggests that vitamin C supplementation can decrease fasting and postprandial oxidative stress and may prevent diabetes complication.     

Comparison of Growth and Fatty Acids Composition of Freshwater Rotifer, Brachionus calyciflorus Pallas, Fed with Two Types of Microalgae at Different Concentrations

As algae and their concentrations are important factors for mass culture of rotifer, two experiments were conducted to find the effects of two types of algae, Chlorella sp. and Scenedesmus obliquus, and three concentration of chosen algae (0.1 × 10⁶, 1 × 10⁶, and 10 × 10⁶ cells/mL) on growth and fatty acid composition of freshwater rotifer, Brachionus calyciflorus. The result of the first experiment showed that the maximum density of rotifer was significantly higher when fed with Chlorella sp. (478 individuals/mL) than fed with S. obliquus (328 individuals/mL). Mean population growth rate (r) was 0.61 and 0.44 for rotifer fed with Chlorella sp. and S. obliquus, respectively. The amount of highly unsaturated fatty acid (HUFA) in rotifer fed with Chlorella sp. (3.32%) was relatively more than those fed with S. obliquus (2.65%). Then, Chlorella sp. was selected based on better performance. In the second experiment, the maximum rotifer density of 108 ± 8, 489 ± 47, and 493 ± 51 individuals/mL was reached after 5 d for the respective Chlorella sp. concentrations; at concentration of 10 × 10⁶ cells/mL, the maximum density of 1820 ± 47 individuals/mL was obtained. Mean growth rate at mentioned concentrations was 0.18, 0.42, and 0.51/d, respectively. Increase in algal concentration was associated with a relative increase in HUFA and decrease in monounsaturated fatty acid.     

Fruit quality and mineral nutrient from exposed verses internal canopy positions of four scitrus varieties

>Quality and mineral content of fruit from internal tree canopies were compared with those from external canopy positions in 4 citrus varities: ‘Kinnow’ mandarin; ‘Redblush’ grapefruit; ‘Valencia’ orange; and ‘Lisbon’ lemon. Fruit weight, total juice per fruit, peel fresh and dry weight, and rind thickness of fruit from internal canopies of all 4 varieties were significantly higher compared with external fruit. Mandarin, grapefruit, and orange fruit from external canopies had higher soluble solids and specific gravity. Fruit from internal canopies of all varieties had generally higher peel concentrations (% dry weight) of N, P and K due to a dilution effect, while the opposite condition existed in mandarin when these elements were expressed on a percent fresh weight basis. Peel Mg and S from external fruit were higher in all varieties, expressed as percentages of either dry weight or fresh weight. Nitrogen content of mandarin and orange juice and Ca content of grapefruit and lemon juice from external fruit were significantly higher compared to those from internal canopy fruit. Elimination of fruit quality and mineral variations as a result of canopy positions is recommended by the means of cultural practices.     

Characteristics of Vegetable‐Based Twin‐Screw Extruded Yellow Perch (Perca flavescens) Diets Containing Fermented High‐Protein Soybean Meal and Graded Levels of Distillers Dried Grains with Solubles

A twin‐screw extrusion study was performed in replicated trials to produce vegetable‐based feeds for juvenile yellow perch. Two isocaloric (3.06 kcal/g) experimental diets were balanced to contain 20 and 40% distillers dried grains with solubles (DDGS) and a constant amount (20%) of fermented high‐protein soybean meal (PepSoyGen) as the fishmeal protein replacers; crude protein content was targeted at 40%. A fishmeal‐based diet was used as a control. Extrusion conditions included conditioner steam (0.11–0.16 kg/min), extruder water (0.11–0.19 kg/min), and screw speed (230–300 rpm). Increasing DDGS from 0 to 40% led to a considerable rise in bulk density, lightness L*), yellowness (b*), and unit density but to decreases in water activity (a_w) and expansion ratio by 12.6, 14.4, 23, 21, 31, and 13%, respectively. The lowest unit density of 791.6 kg/m³ and highest bulk density of 654.5 kg/m³ were achieved with diets containing 20 and 40% DDGS, respectively; changes in DDGS content did not affect extrudate moisture, absorption index, or thermal properties. Raising DDGS from 0 to 40% resulted in an increase in water solubility and redness (a*) by 13.4 and 35%, respectively. All extrudates had high durability (>98%), and low a_w of less than 0.5. Overall, this study yielded viable feeds for yellow perch.     

Effects of Bicarbonate Content of Irrigation Water on Nutritional Disorders of Some Apple Varieties*

Effects of varying concentrations of bicarbonate in the irrigation water on seedlings of ‘Red Delicious,’ ‘Golden Delicious,’ and ‘Golab-e-Kohanz’ apple cultivars, grown in a greenhouse, were studied. To conduct this experiment, ammonium bicarbonate was used in order to obtain bicarbonate concentrations at 5, 10, 15, and 30 meq/L, and sulfuric acid was used to obtain a 0 level of bicarbonate in water. The electrical conductivity (EC) of the leachate water was nearly the same for 0, 5, and 10 meq/L bicarbonate, but doubled with the increase from 10 to 30 meq/L. Also, the bicarbonate concentration in the leachate increased with increasing levels of irrigation water bicarbonate, even though it was much lower in the leachates. Different bicarbonate levels in the irrigation water significantly reduced chlorophyll development. The difference was significant only between 30 mg/L and other levels after 40 d, but after 120 d (except for 0 and 5 meq/L) treatments at all other levels showed reduced chlorophyll intensities. There were also significant differences in chlorophyll intensities between different apple varieties before and up to 40 d of bicarbonate treatment, with ‘Golden Delicious’ having the most chlorophyll among the three varieties. The different intensities, however, were not significant after 80 and 120 d of bicarbonate treatments. After 120 d, the 0, 5, 10, 15, and 30 meq/L of bicarbonate had reduced the chlorophyll intensities by 4%, 6.5%, 18.2%, 35.6%, and 59.4%, respectively. Increasing levels of bicarbonate increased the leaf concentrations of nitrogen (N), potassium (K), and phosphorus (P), but lowered the concentrations of iron (Fe), magnesium (Mg), and manganese (Mn) and did not affect calcium (Ca), copper (Cu), or zinc (Zn) levels. Considering the equilibrium level of 3.5–4 mmole bicarbonate per liter of soil solution in calcareous soils brought about by CO₂ pressures and calcium carbonate (CaCO₃) minerals in the solid phase, it would not seem necessary to neutralize the irrigation water bicarbonates for concentrations below 5 meq/L. Instead, improvements in root development by improved soil aeration and prevention of excessive irrigation is probably beneficial. However, when the concentration of bicarbonate exceeds 5 meq/L in irrigation water, it is probably necessary to neutralize the bicarbonates for long-term irrigation purposes.     

Influence of superabsorbent polymer rates on growth of saffron replacement corms

Mother corm size is the most important factor for production of replacement corms, flower, and stigma yield in saffron. In semi-arid regions, water shortage is a deterrent agent for appropriate corm growth of saffron. Therefore, in this experiment the effects of six levels of superabsorbent polymer (SAP) including 0, 10, 20, 30, 40, and 50 kg ha^-1 was investigated on growth indices of replacement corms of saffron. For this purpose, an experiment was evaluated at the research farm of the Saffron Research Group, Sarayan Faculty of Agriculture, University of Birjand, Iran, during 2013-2015. Results showed that SAP application did not considerable effect on corm growth indices in the first life cycle of saffron. Nevertheless, consumption of 30-40 kg ha^-1 SAP somewhat improved the number and total weight of replacement corms per clone. In the second life cycle of saffron, the positive impact of SAP was clearly observed on the growth of replacement corms. The application of 40 kg ha^-1 SAP increased the amount of number of replacement corms per clone by 13%, total weight of replacement corms per clone by 36%, and scale weight of corms per clone by 50% compared with control. In addition, the amount of mean weight of replacement corms and mean number of buds per corm in treatment of application of 40 kg ha^-1 SAP were 29 and 27% higher than the control treatment, respectively. SAP application decreased the amount of non-standard (< 8 g) corm production while significantly increased the percentage of corms with standard weight. Overall, the increasing effect of SAP application on corm weight, bud number, and standard corm yield was higher than the number of produced corms per clone. In addition, water-use efficiency in SAP application treatments (6.1 kg standard corm m^-3) was more than the control (4.34 kg m^-3) treatment. In total, SAP application is an appropriate strategy for production of standard saffron corms in semi-arid regions.     

Biomass partitioning during the life cycle of saffron (<Emphasis Type="Italic">Crocus sativus</Emphasis> L.) using regression models

In this study saffron biomass partitioning was investigated in the research station of the Saffron Research Group, University of Birjand, Iran during 2009 - 2010. Plant sampling was done 25 times during the crop growth cycle. In each sampling date, the amounts of corm dry weight, root dry weight, root length, leaf dry weight, leaf area, bud number, bud dry weight (nodes on the surface of the corm), and flower weight were measured. Finally, different regression models were tested for predicting biomass partitioning in saffron. The cubic polynomial model was found to be the best for predicting biomass changes in most saffron organs (R ² = ~74%). Total corm dry weight showed a decreasing trend up to the 120^th day of plant growth and then increased until the end of the life cycle (mid-May). However, different trends were observed for root and leaf dry weights. Root and leaf dry weight increased up to the 120^th and 150^th day of the plant growth cycle, respectively, followed then by decreasing trends. Therefore, in the early growing season, leaves and root systems were developed using mother corms reservoirs, but at the end of the growth cycle replacement corms were grown by translocation of reservoirs from other saffron organs. In addition, the number and dry weight of buds had increasing trends during 160 days of measurement from the beginning of the growing season. The total length of roots and leaf area increased up to the middle of the growth cycle (Feb. 10) and then decreased. Moreover, saffron flower yield showed a rapid increasing trend in the first phase of the flowering period and then declined with a slower trend during the second flowering phase.