Valuation of gamma irradiation for proficient production of parasitoids (Hymenoptera: Chalcididae & Eucoilidae) in the management of the peach fruit-fly,Bactrocera zonata (Saunders)

Recognizing the potential significance of using nuclear techniques in biological control, investigations were conducted on the rearing of parasitoids of the peach fruit-fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae) to lead to a greater flexibility in the use of irradiated hosts. For improving mass production of the biological control agents, the use of irradiated fruit-fly larvae at the dose of 15 Gy proved useful for enhancing the parasitism and adult emergence of the larval parasitoid, Trybliographa daci (Weld) (Hymenoptera: Eucoilidae) due to no negative repercussions on parasitoid development. Overall, parasitism by the parasitoid increased with age of the host larvae; however, significantly higher parasitism occurred on 4 d-old irradiated larvae of B. zonata compared to those aged 5 d. The female parasitoids preferred the irradiated larvae, and significantly higher numbers of larvae were parasitized compared with non-irradiated larvae. There was no significant difference in adult parasitoid emergence with respect to the sex of the host. A radiation level of 80 Gy was the best dose for rearing of the pupal parasitoid, Dirhinus giffardii (Silvestri) (Hymenoptera: Chalcididae) owing to broad tolerances in the use of irradiation for the rearing of fruit-fly's parasitoids. Percentage parasitism by D. giffardii varied with host pupal age, and the preference of the female parasitoid was lower on 48 h old host pharate pupae due to optimum size and mass of host. Present findings further revealed that the 24 h old host pupae of B. zonata were relatively more suitable for the maximum parasitism and progeny production of D. giffardii. Parasitisms by D. giffardii and T. daci were significantly higher on B. zonata host when parasitoids were released at a density of 3000 individuals per acre (7500 per hectares) than the other release rates of parasitoids for the management of fruit-flies in mango orchards. The implementation of these findings ought to help improve the mass production of parasitoids and the effectiveness of releases of biocontrol agents for control of B. zonata in mango plantations.     

Effect of Propionibacterium acnes-containing immunostimulant on interferon-gamma (IFNγ) production in the neonatal foal

Production of the Th1 cytokine interferon gamma (IFNγ) is associated with resistance to intracellular pathogens, including Rhodococcus equi. While neonatal foals are initially deficient in IFNγ production, expression of this cytokine increases throughout their first year of life. This is presumably the result of stimulation by environmental antigens including pathogen associated molecular patterns (PAMPS) signaling through toll-like receptors (TLR). This increased expression of IFNγ is likewise associated with an age-related resistance to R. equi infection. While immunostimulants containing PAMPS have been administered to adult horses in an attempt to modify their immune response, the effect of these materials on IFNγ expression in foals is unknown. The main objective of this study was to determine the effect of administering a commercial immunomostimulant EqStim? (Propionibacterium acnes) on IFNγ production measured using intracellular staining (IFNγ) and RT-PCR.     

Metabolomic analysis of Ranunculus spp. as potential agents involved in the etiology of equine grass sickness

Identification of toxic or harmful agents continues to be a key goal in agricultural chemistry. This paper reports a metabolomic analysis of Ranunculus repens and related species, which were recently postulated to be cocausative agents in the etiology of equine grass sickness (EGS). Specifically, samples collected at EGS sites were compared with those from non-EGS sites. Furthermore, interspecific and seasonal variations and the species' response to edaphic and climatic factors were investigated. (1)H NMR spectroscopy in combination with multivariate data analysis was applied to the crude methanol extracts of the Ranunculus samples, as well as their chloroform fractions. Samples from EGS sites were significantly different from control samples. The metabolite composition varied greatly between different Ranunculus species. No significant changes could be observed between samples collected in different seasons. This work provides strong evidence that Ranunculus is involved in the etiology of EGS and has implications for agricultural management of pastures.     

Effect of pre-harvest foliar application of amino acids and seaweed (Ascophylum nodosum) extract on growth,yield, and storage life of different bell pepper (Capsicum annuum L.) cultivars grown under hydroponic conditions

The study was set up to evaluate the efficiency of amino acids and seaweed on vegetative growth, reproductive phase, yield, and postharvest storage quality of hydroponically grown bell pepper cultivars “Sven Rz F-1” and “Red Knight.” Different concentrations of amino acid and seaweed were sprayed on bell pepper plants under hydroponic conditions. Pre-harvest foliar application of amino acids and seaweed significantly increased plant height, number of leaves, leaf area, yield per plant, number of marketable fruits per plant, average fruit diameter, fruit wall thickness, and average single fruit weight. Amino acid and seaweed significantly improved postharvest physicochemical quality of both bell pepper cultivars under extended cold storage conditions. Conclusively, amino acid as well as seaweed extract not only improved growth, development, yield, and overall quality of bell pepper cultivars but also increased storage life with reduced weight loss and decay along with better physicochemical quality.     

Screening drought-tolerant genotypes in bread wheat (Triticum aestivum L.) using different multivariate methods

Wheat (Triticum aestivum L.) is one of the most widely cultivated crops in rainfed areas of Iran, where drought is the main limiting factor on yield. The object of this study was the identification of drought-tolerant genotypes in bread wheat. Forty bread wheat genotypes were tested in separate experiments under drought stress and normal conditions in two years (2009–2010 and 2010–2011). Nine drought-tolerance/susceptibility indices including stress susceptibility index (SSI), mean productivity (MP), tolerance (TOL), stress tolerance index (STI), geometric mean productivity (GMP), yield index (YI), yield stability index (YSI), linear regression coefficient (β) and drought response index (DRI) were determined. Simultanously applied factor analysis used two factors instead of nine indices in this study. Mahdavi was recognized as the most drought-tolerant genotype in both years based on factor analysis. In this study an equation was developed for estimating the Stress Tolerance Score (STS). The results of the equation were identical to those of factor analysis in both years. The equation was much easier to use than factor analysis and is suggested as a screening tool for the identification of drought-tolerant genotypes. In this study, Mahdavi was the most drought-tolerant genotype also corresponding to this equation.     

Evaluating the effectiveness of biofertilizer on salt tolerance of cotton (Gossypium hirsutum L.)

In the present study, the effectiveness of biofertilizer containing plant growth promoting rhizobacteria was evaluated on growth and physiology of cotton under saline conditions. Cotton plants were exposed to different levels of NPK (50%, 75%, and 100% of recommended levels) along with coating with biofertilizer under saline (15 dS m^?1) and non-saline conditions. It was observed that the biofertilizer seed coating improved growth, physiological (relative water content and chlorophyll content index), and ionic (K⁺/Na⁺) characteristics under saline and non-saline conditions. However, shoot growth (shoot fresh and dry weight) and leaf gas exchange characteristics (CO₂ assimilation rate, A; intercellular CO₂ concentration, C_i; transpiration rate, E; stomatal conductance, g_s) were decreased by biofertilizer coating under saline condition. Increasing levels of NPK fertilizer increased shoot growth, whereas root growth was maximum at 75% NPK level under saline conditions. The results of the study indicate that the biofertilizer application was very effective for cotton plant in non-saline conditions but not very effective in saline conditions.     

Improvement of Antioxidant System and Decrease of Lignin by Nickel Treatment in Tea Plant

The effect of nickel (Ni) on the activities of antioxidant enzymes was evaluated in suspension-cultured cells of tea (Camellia sinensis L. cv. ‘Yabukita’) and two-year-old rooted cuttings of tea (Camellia sinensis L. assamica × sinensis). Suspension-cultured cells were grown in B5 medium and treated with 40 μM of Ni for 24 h. Tea plants were grown in a modified Hoagland solution and treated for one week with 40 μM of Ni. The activities of superoxide dismutase, catalase, ascorbate peroxidase, and ionically wall-bound peroxidase of both Ni-treated tea cells and Ni-treated tea plants increased compared with those of control groups. The activities of soluble peroxidase and covalently wall-bound peroxidase, as well as the lignin content of both tea cells and tea plants, decreased under Ni treatment. Thus it seems that Ni may have beneficial effects on tea plants via elevation of antioxidant activity and decrease of lignification of the walls.     

BORON DEFICIENCY IN RAINFED WHEAT IN PAKISTAN: INCIDENCE,SPATIAL VARIABILITY AND MANAGEMENT STRATEGIES

Boron (B) deficiency is potentially an important nutrient constraint in calcareous soils. We determined B deficiency incidence and spatial distribution in rainfed wheat (Triticum aestivum L.) in 1.82 Mha Pothohar plateau in Pakistan, its relationship with soil types, crop responses to B, and internal B requirement and B fertilizer use efficiency of wheat. Plant and soil analyses indicated deficiency in 64% of the 61 sampled fields; geostatistics-aided contour maps delineated B deficient areas. In rainfed field experiments, B use increased wheat yields up to 11%. Fertilizer requirement was 1.2 kg B ha^?1; critical B concentration (mg kg^?1) ranges were: young whole shoots, 4–6; flag leaves, 5–7. Boron uptake by wheat was 0.14–0.58% of applied dosage, leaving substantial residual impact. Highly cost-effective B use or B-efficient genotype adoption can enhance wheat productivity and grower-income. Such effective nutrient assessment and management approaches can be beneficially adopted elsewhere as well.     

Effects of Coenzyme Q10 on the ratio of TH1/TH2 in Experimental Autoimmune Encephalomyelitis Model of Multiple Sclerosis in C57BL/6

Background: Multiple sclerosis (MS) is known as a progressive central nervous system inflammatory disease. Certain factors, such as interleukins, inflammatory cells, and oxidative stress are supposed to involve in MS etiology. Because of the important role of oxidative stress, antioxidant therapy for MS has received more attention. Although coenzyme Q10 (CoQ10) acts as an antioxidant, there is a lack of enough research on its effects on MS. Therefore, the present research was designed. Methods: C57BL/6 female adult mice (n = 30) were used in this study. The animals were randomly divided into trial and control groups. To induce MS, routine procedure for experimental autoimmune encephalomyelitis (EAE) was used, and scoring was performed based on clinical signs. By detecting score one, CoQ10 administration was started (10 mg/kg/three weeks). By using ELISA and real-time PCR, the brain levels of TNF-, IL-10, IL-4, and IL-12 were studied. Statistical tests were used to analyze the data and the P value less than 0.05 was considered to be significant. Results: Clinical symptoms in EAE animals were significantly decreased (P<0.05) as compared to control ones. In addition, the level of the TNF- was significantly decreased following CoQ10 administration versus IL-10. The ratio of TH1/TH2 interleukins in treated animals was significantly less than that in non-treated animals (P<0.01). Conclusion: Our findings showed that CoQ10 is capable of suppressing the inflammatory pathway of MS. Key Words: Experimental autoimmune encephalomyelitis (EAE), Multiple Sclerosis (MS), Coenzyme Q10 (CoQ10)     

Mixed Fertilizer can Improve Fruit Yield and Quality of Field-Grown Tomatoes Irrigated with Saline Water

Growing tomatoes using saline water and in soils with poor nutrient contents is challenging. The objectives of this work were to: (i) examine the yield and quality of tomatoes (Lycopersicon esculentum L.) irrigated with different saline water [electrical conductivity (ECi) = 3, 6 and 9 dS m^?1]; and (ii) study the effect of fertilizer: inorganic, organic, and a mixed of both on tomatoes grown under saline conditions. Fruit weight and quality attributes including size, color, soluble solids, acidity, EC, and pH were measured. Growing tomatoes under 3 and 6 dS m^?1 produced the highest yield, whereas irrigating with 9 dS m^?1 reduced yield. The mixed fertilizer slightly ameliorated the yield reduction caused by salinity. Using organic fertilizer alone produced the lowest fruit yield. Fruit quality was more affected by salinity than fertilizer. The best growing conditions for tomatoes were in plots irrigated with 6 dS m^?1 water under mixed fertilizer treatment.