Preliminary studies on two Diaspididae (Hemiptera) species feeding on Johnsongrass (<Emphasis Type="BoldItalic">Sorghum halepense</Emphasis>) in Turkey

The scale insects Acanthomytilus sacchari (Hall) and Duplachionaspis erianthi Borchsenius (Hemiptera, Diaspididae) are newly recorded as indigenous insects from Turkey. Both A. sacchari and D. erianthi were found to feed only on rhizomes of Johnsongrass. A field study was conducted to determine host ranges and feeding effects of these scale insects on Johnsongrass, Sorghum halepense (L.) Pers. No feeding of these species was observed on Zea mays L. (maize), Sorghum sudanense Staph. (sorghum), Aegilops triuncialis L. (barbed goatgrass), Avena fatua L. (wild oat), A. sterilis (sterile oat), Bromus tectorum L. (downy brome), Cynodon dactylon (L.) Pers. (bermudagrass), Phragmites australis (Cav.) Trin. ex Steudel (common reed), Poa bulbosa L. (bulbous bluegrass), or Secale montanum Guss. (wild rye). The mean infestation rates of the scale insects on Johnsongrass in southeastern Anatolia were 11.47% and 1.64% for A. sacchari and D. erianthi, respectively. Further investigations are required to clarify their biology and damage to Johnsongrass under field conditions.     

Effect of thiamine injection on growth performance,hematology and germinal vesicle migration in sterlet sturgeon Acipenser ruthenus L.

The present study aimed to investigate the effect of thiamine on growth, hematological, egg thiamine content and oocyte nucleus migration indices in sterlet sturgeon (Acipenser ruthenus). A total of 45 female fish (698.6 ± 8.9 g) were distributed in nine fiberglass tanks with three treatments (each in three replicates). Experimental fish were fed once a day with practical diet supplemented with 1 g kg^?1 amprolium hydrochloride (as the antithiamine) for 5 months before spawning. Thiamine hydrochloride was injected to fish with one of three doses at 0, 5 and 50 mg kg^?1 body weight (BW) at three different stages. At the end of each month, fish were weighed and growth parameters such as weight gain, specific growth rate, feed efficiency and final weight were determined. At the end of the 5-month period, hematological parameters and egg thiamine content were measured. The results showed no significant differences in terms of growth performance. Hemoglobin, number of red blood cells and white blood cells were not significantly different among the treatments, but hematocrit was significantly higher in fish injected with 5 mg kg^?1 BW thiamine. The mean corpuscular volume and mean corpuscular hemoglobin were not significantly different, but lower value of mean corpuscular hemoglobin concentration was observed in fish injected with 5 mg thiamine. Percentage of lymphocytes, neutrophils, eosinophils and monocytes were not significantly different among treatments. The results of the germinal vesicle migration index at different stages showed no significant differences in different groups. Results showed that free thiamine, thiamine pyrophosphate and total thiamine in eggs significantly increased at 50 mg kg^?1 injection dose compared with the control, but no significant different was found in thiamine monophosphate. The results revealed that thiamine injection to sterlet broodstocks has positive accumulation in egg thiamine content and some hematological parameters but have no effect on growth and ovarian maturation. We conclude that thiamine can affect some physiological features of broodstock, which needs to be specified in further studies.     

The Effect of Salicylic Acid On Photosynthetic Characteristics,Growth Attributes,and Some Antioxidant Enzymes On Parsley (Petroselinum crispum L.) Under Salinity Stress

Gesunde Pflanzen - Parsley (Petroselinum crispum&nbsp;L.) is widely used in food, medicine, cosmetics, and pharmaceutical industries. This research was conducted to determine the effect of six...     

Assessment of spatial and seasonal changes in groundwater nitrate pollution of agricultural lands through ordinary and indicator kriging techniques

Geostatistical approaches (ordinary kriging (OK) and indicator kriging (IK)) were used in this study to investigate the spatial and temporal variations in groundwater nitrate concentrations in Çar?amba plain of Turkey. Groundwater samples were taken in April 2012, July 2012, September 2012 and March 2013 from 78 groundwater wells. The experimental semivariograms were often fitted well by a Gauss model for April 2012 and September 2012, whereas a spherical model was fitted to experimental semivariograms for July 2012 and March 2013. Spatial distribution maps revealed that groundwater nitrate concentrations were above the threshold value of 50 mg L^?1 specified for drinking water in 4.3% of the study area in April 2012, 40.8% in July 2012, 32.8% in September 2012 and 19.1% in March 2013. Probability maps created with IK showed that 3.1% and 3.2% of the total area had very strong probability (0.8–1.0) of exceeding the threshold nitrate concentration in July 2012 and September 2012, respectively. Current findings revealed that groundwater nitrate concentrations changed seasonally and increased much more in summer. It was concluded that OK and IK may yield significant outcomes for groundwater management, identification of risky sites for potential pollution and identification of the sites with excessive fertilizer uses.     

Concentration and size distribution of airborne particles in a broiler house

Airborne dust particles were sampled in a broiler house using the quartz crystal microbalance cascade impactor designed for the measurement of mass concentration and size distribution from 0.05 to 25 gm. No significant difference was noticed in the dust concentration from morning to evening or at different sampling sites in the broiler house. The concentration of airborne dust particles decreased as the age of the chickens increased. Ratio of dust particles smaller than 0.8 pm to the total dust ranged from 10 to 50%. The highest concentration of dust was in the particle size range of 3.2 μm. The fogging system in use reduced the concentration of larger particles but not that of the smaller particles.     

Binding,fractionation, and distribution of Cs,Co, and Sr in a US coastal soil under saturated and field capacity moisture regimes

Purpose

The concerns of the public on safe handling of nuclear energy power facilities have increased due to the recent nuclear plant accidents in Japan and others. Cesium, cobalt, and strontium are a few of the major radionuclides released from nuclear power plant accidents. The objectives of this study are to investigate binding, distribution, fractionation, and transformation of cesium (Cs), cobalt (Co), and strontium (Sr) in a US coastal soil under saturated paste (SP) and field capacity (FC) moisture regimes.

Materials and methods

There are four major nuclear power plants in the coast region around the northern Gulf of Mexico where coastal soil often undergoes soil moisture change. A coastal soil was taken from the middle region of these major nuclear power plants and spiked with different concentrations of cesium, cobalt, and strontium salts. The sequential selective dissolution technique was used to investigate the transformation and fractionations of these metals in the coastal soils affected by moisture regime, a key factor in the coastal environment.

Results and discussion

The adsorption kinetics showed that both Co and Sr reached the adsorption plateau even after 5 h of adsorption, indicating a fast initial adsorption process in the coastal soil. Cesium, cobalt, and strontium were dominantly presented in the soluble and exchangeable form (EXC) (Cs?>?Co and Sr), which linearly increased with the addition levels, possessing the high bioavailability, mobility, and ecotoxicity. Saturated regime significantly reduced the soluble and exchangeable form compared to field capacity moisture regime.

Conclusions

The current study provides the fundamental understanding for designing the cost-effective remediation technology to remediate these metals in coastal soil by targeting on the soluble and exchangeable forms and better prepare the USA for future potentially nuclear power plant accidents.

     

Evaluating and Modeling of the Seedling Growth Ability of Wheat Seeds as Affected by Shallow-Saline Groundwater Conditions

The adverse effects of shallow-saline groundwater may vary among crucial growth stages of crops by decreasing crop growth and productivity. The present study aimed to assess the germination and seedling growth ability of wheat seeds grown in four different (0.38, 2.0, 4.0, and 8.0 dSm^?1) groundwater salinities (GWS) and three (30, 55, and 80?cm) groundwater depths (GWD) condition. To achieve this aim, wheat crops were grown in drainable lysimeters under rain shelter conditions until the maturity stage, and then wheat seeds were harvested from various saline groundwater conditions. Afterward, wheat seeds were germinated to identify the performance of germination and seedling growth attributes. Response surface methodology (RSM) was used to determine the optimal growing wheat seeds condition, which had high early seedling growth performance. The results showed that the seedling growth performance of wheat seeds increased with increasing GWDs, while decreased with increasing GWSs. Based on the RSM findings, we suggest that GWD and GWS should be at least 42?cm and at most 5.46 dSm^?1, respectively, for sustainable higher wheat yield and seed quality. Finally, this study could provide considerable information for selecting strong and healthy wheat seeds grown under shallow saline groundwater conditions.

     

Remediation of lead-, arsenic-, and cesium-contaminated soil using consecutive washing enhanced with electro-kinetic field

Purpose

Extensive deposition of Pb, As, and Cs in soils may damage ecosystems and human’s health. Soil washing is the most conventional remediation method, and its efficiency depends on metal solubility in soil. This study aims to optimize operating variables of electro-kinetic field (EKF)-enhanced soil washing procedures.

Materials and methods

Soil samples from a Mississippi River Delta rice field were homogeneously spiked with Pb, As, and Cs, and contaminated soil was aged for 3 months. The remediation involved a first stage electro-kinetic process, followed by a soil washing procedure. Soil pH changes under EKF were studied. Effects of citric acid and reversed EKF were investigated for alleviating possible alkaline precipitation. In the washing procedure, soil washing time and cycles with different extractants were examined. The overall EKF-enhanced soil washing efficiencies were discussed as well.

Results and discussion

The implement of EKF offered an acidic soil environment around the anode areas for solubilizing metal(loid)s. Combined with EKF, citric acid was more conductive to desorb metal(loid)s. In addition, the reversed EKF effectively alleviated metal(loid) precipitation caused by alkalization in the first stage cathode areas. The EKF significantly enhanced metal(loid) extractions in the anode area of soils using Na₂EDTA, CaCl₂, and citric acid at pH of 2. The most preferable removal of Pb (80–98 %), As (48–63 %), and Cs (10–13 %) was achieved with three extractants. CaCl₂ and citric acid were proved to be suitable alternatives to Na₂EDTA for Pb extraction. A washing process of 2 h extraction with double washing cycles was optimized.

Conclusions

Soil washing time and cycles were major factors governing the metal(loid) removal from soil. Washing process of 2 h extraction with double cycles was optimized for further extraction based on higher washing efficiency. The EKF effectively improved washing efficiency while some electrical parameters need further studies for cost performance consideration.

     

Using expert knowledge data to validate crop models on local situation data

Cropping system models are widely used tools for simulating the growth and development of crops at field scale. However, it is often difficult to satisfy their detailed input and output data requirements for a proper evaluation of model. In this study, expert knowledge data were used as alternative source to fulfil these data requirements. The model was first calibrated for major crops of the studied area and then evaluated for the same crops by using expert knowledge data. Results showed that the model accurately simulated above-ground biomass and grain yield with a relative root mean square error (RRMSE) of 20% and 17%, respectively. On the other hand, simulated results were less satisfactory for N uptake and cumulated evapotranspiration with RRMSE of 27% and 31%, respectively. The model simulated cumulative variables more accurately than dynamic variables. The results of this study suggest that expert knowledge can be used to get data for intermediate variables rarely measured in experiments used for calibration (green leaf area index, actual evapotranspiration, rooting depth) in typical crop management conditions in the region. This approach enables a global and dynamic evaluation of cropping system models when experimental data is unavailable for large heterogeneous areas in a region.