Genetic Analysis of Water Use Efficiency in Rice (Oryza sativa L.) at the Leaf Level

Carbon isotope discrimination (?¹³C) is considered as an index of leaf-level water use efficiency, an important objective for plant breeders seeking to conserve water resources. We report in rice a genetic analysis for ?¹³C, leaf structural parameters, gas exchange, stomatal conductance, and leaf abscisic acid (ABA) concentrations. Doubled haploid and recombinant inbred populations, both derived from the cross IR64 × Azucena, were used for quantitative trait locus (QTL) analysis following greenhouse experiments. ?¹³C QTLs on the long arms of chromosomes 4 and 5 were colocalized with QTLs associated with leaf blade width, length, and flatness, while a QTL cluster for ?¹³C, photosynthesis parameters, and ABA was observed in the near-centromeric region of chromosome 4. These results are consistent with phenotypic correlations and suggest that genetic variation in carbon assimilation and stomatal conductance contribute to the genetic variation for ?¹³C in this population.     

Effect of adding ketamine to pethidine on postoperative pain in patients undergoing major abdominal operations: a double blind randomized controlled trial

To determine the effect of adding ketamine to pethidine in reducing post-operative pain in patients undergoing major abdominal operations, in a double blind randomized controlled trial, 100 patients aged 15-60 years who were candidate for elective major abdominal surgery allocated into two groups of pethidine + ketamine group (5 mg pethidine and 0.25 mg kg(-1) ketamine) or pethidine and placebo group (10 mg pethidine and NS) according to the regimen prescribed in postanesthesia care unit. Severity of pain (using visual analogue scale), prescribed dose of pethidine and side effects were recorded until 24 h after operation. Regarding post-operative pain, pethidine + ketamine group showed significant lower scores in all the times except 0 min, 2, 6 and 16 h. Nausea was significantly less frequent amongst pethidine + placebo group at times of 0, 15, 30 and 45 min (p < 0.05). Comparison of two groups did not show significant differences in prescribed pethedine dose in 0, 9, 12, 16, 20 and 24 h (p > 0.05). Yet, the mean dose of administered pethidine as rescue analgesic was significant lower in pethidine + ketamine group compared to pethidine + placebo group (112 +/- 31.5 mg vs. 133.5 +/- 24.5 mg, p < 0.001). In conclusion, our results showed that co-administration of ketamine and pethidine in postanesthesia care unit will improve postoperative pain and reduce narcotic consumption. It may, however, increase rate of postoperative nausea in the first hour after operation.     

The children reference range of thyroid hormones in Northern Iran

Hypothyroidism is associated with mental and growth abnormality in children. The aim of this study was to determine the reference range of thyroid stimulating hormone (TSH). Thyroxin (T4) and triodothyronine (T3) of children in Northern Iran. The sample population for this study consists of subjects of 4 age groups up to 21 years. The subjects were selected randomly from people referred to Danesh Medical Diagnostic Laboratory in Gorgan Northern Iran. Thyroid hormone level were investigated with Radio immunoassay. The mean concentration for T4, T3, TSH for the sample population of 4 groups were as follow (113.5, 107.4, 102.9, 99.2 nmol L(-1)), (1.9, 1.7, 1.9, 1.6 nmol L(-1)) and (2.1,3.5, 2.9, 2.7 mIu L(-1)). The mean value of T3, TSH were higher for females but the mean value of T4 was slightly higher in males. The findings of this investigation indicated that there is an inverse age correlation in particular for T4 in all age groups. On the bases of the results from this study, we conclude that reference range, in all age groups and lower, upper limits of our reference range are not universally similar; therefore determination of reference range in each region is a critical need for clinical practice.     

Effects of irrigation strategies and soils on field-grown potatoes: Gas exchange and xylem [ABA]

Gas exchange was measured in potatoes (cv. Folva) grown in lysimeters (4.32 m²) in coarse sand, loamy sand, and sandy loam and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. PRD and DI as water-saving irrigation treatments received 65% of FI and started after tuber bulking and lasted for six weeks until final harvest. Midday photosynthesis rate (A_n) and stomatal conductance (g_s) of fully irrigated (FI) plants were lowest in coarse sand and mean A_n of diurnal measurements in FI, PRD and DI tended to be lower in this soil as compared with the loamy sand and sandy loam. The results revealed that diurnal values of A_n and g_s in PRD and DI were consistently lower than FI without reaching significant differences in accordance with findings that xylem [ABA] in PRD was significantly higher than FI, and tended to be higher than in DI. Diurnal measurements showed that A_n reached peak values during mid-morning and midday, while g_s were highest during the morning. Intrinsic water use efficiency (A_n/g_s) correlated linearly well with the leaf to air vapor pressure deficit (VPD) and the slope of the line revealed the rate of A_n/g_s increase per each kPa increase in VPD, i.e. approximately 10 μmol mol⁻¹. Transpiration efficiency (A_n/T) of PRD was higher than DI, which shows slightly better efficient water use than DI. The slope of the linear relationship between transpiration efficiency and VPD decreased from −2.03 to −1.04 during the time course of the growing season, indicating the negative effect of leaf ageing on photosynthesis and thus on plant water use efficiency. This fact shows the possibility to save water during last growth stages through applying water-saving irrigations without much effect on transpiration efficiency.     

Erosional impacts on soil properties and corn yield on Alfisols in central Ohio

Accelerated soil erosion can impact upon agronomic productivity by reducing topsoil depth (TSD), decreasing plant available water capacity and creating nutrient imbalance in soil and within plant. Research information on soil‐specific cause – effect relationship is needed to develop management strategies for restoring productivity of eroded soils. Therefore, two field experiments were established on Alfisols in central Ohio to quantify erosion‐induced changes in soil properties and assess their effects on corn growth and yield. Experiment 1 involved studying the effects of past erosion on soil properties and corn yield on field runoff plots where soil was severely eroded and comparing it with that on adjacent slightly eroded soil. In addition, soil properties and corn grain yield in runoff plots were compared on side‐slopes with that on toe‐slopes or depositional sites. Experiment 2 involved relating corn growth and yield to topsoil depth on a sloping land. With recommended rates of fertilizer application, corn grain yield did not differ among erosional phases. Fertilizer application masked the adverse effects of erosion on corn yield. Corn grain yield on depositional sites was about 50 per cent more than that on side‐slope position. Corn plants on the side‐slope positions exhibited symptoms of nutrient deficiency, and the ear leaves contained significantly lower concentrations of P and Mg and higher concentrations of Mn and K than those grown on depositional sites. Corn grain yield in experiment 2 was positively correlated with the TSD. Soil in the depositional site contained significantly more sand and silt and less clay than that on the side‐slope position. There were also differences in soil properties among erosional phases. The soil organic carbon (SOC) content was 19\7 g kg⁻¹ in slightly eroded compared with 15\1 g kg⁻¹ in severely eroded sites. Aggregate stability and the mean weight diameter (MWD) were also significantly more in slightly eroded than severely eroded soils. Adverse effects of severe erosion on soil quality were related to reduction in soil water retention, and decrease in soil concentration of N and P, and increase in those of K, Ca and Mg. Severe erosion increased leaf nutrient contents of K, Mn and Fe and decreased those of Ca and Mg. Corn grain yield was positively correlated with aggregation, silt and soil N contents. It was also negatively correlated with leaf content of Fe. Copyright © 2000 John Wiley & Sons, Ltd.     

Prediction of soil saturated water content using evolutionary polynomial regression (EPR)

The measurement of saturated water content (SWC) is necessary in the estimation of soil water retention and unsaturated hydraulic conductivity curves. In several studies, pedotransfer functions (PTFs) were developed to predict SWC. Among them, evolutionary polynomial regression (EPR) is one that can operate on large quantities of data in order to capture nonlinear and complex interactions between the variables of the system. In this study, the evolutionary data-mining technique was used to derive new PTFs and different methods were evaluated, such as the soil porosity method, Rosetta method, and others, for the estimation of SWC. For this purpose, 270 soil samples (3:1 ratio for development and validation) from three data sets were used. Among 190 PTFs provided by EPR, one equation with the highest accuracy and the least number of inputs was selected. The EPR predictions were compared with the experimental results as well as the PTFs proposed in previous studies. Comparison of the statistical indicators showed that the ‘proposed PTF’ and ‘porosity method’ are the best and worst methods for the prediction of SWC, respectively. Also, good predictions were achieved from the proposed approaches by the groups of Scheinost, Vereecken, and Williams.     

Comparison of Different Methods of Estimating Saffron Yield Based on Soil Properties in Golestan Province

ABSTRACT

Evaluation of the relationship between soil properties and saffron yield estimation may contribute to agricultural planning in finding suitable lands for the growth of this valuable product. This study aimed to investigate the performance of artificial neural network (ANN), multiple linear regression (MLR), and adaptive neuro-fuzzy inference system (ANFIS) in terms of saffron yield estimation in some lands of Golestan province, Iran. To this end, 100 areas under saffron cultivation were selected. For rapid and low-cost saffron yield estimation, six different models were designed based on soil properties as inputs using MLR, ANN, and ANFIS methods. According to the results, ANN showed the highest accuracy (R² = 0.58–0.89) in estimating saffron yield as compared to MLR (R² = 0.41–0.47) and ANFIS (R² = 0.41–0.69) models. A comparison of the results obtained from the six models defined in these three methods indicated that Model 4 (R² _Reg = 0.45, R² _ANFIS = 0.57, R² _ANN = 0.87), with the inputs, organic phosphorus, potassium, and calcium carbonate, was the best model in terms of accuracy and speed in estimating saffron yield phosphorus. The RI indexes for ANN in the model were 50% and 34% relative to MLR and ANFIS, respectively, demonstrating the higher accuracy of ANN in saffron yield estimation. The study results can be used to identify lands suitable for saffron cultivation in the study area using organic phosphorus and organic matter levels in the soil.     

Histomorphology of the lower respiratory tract in the Indian crested porcupine (Hystrix indica)

The Indian crested porcupine (Hystrix indica) (ICP) is widely distributed in Asia; however, compared with other rodents, little is known about the structures of its respiratory system. The aim of this study was to evaluate the histomorphology of the lower respiratory portion of the ICP to provide a basis for the identification of the normal structure of this organ. The larynx, trachea and lungs of four carcasses of adult Indian crested porcupines (two males and two females) were dissected and fixed in 10% neutral-buffered formalin. The gross anatomy and histology of all specimens were evaluated. A macroscopic evaluation showed unique structures in the ICP respiratory system, including the presence of a chamber-like structure at the origin of the bronchi and a difference in epiglottis shape between males and females. Histologically, the stratified squamous epithelium covered the epiglottis and arytenoid cartilage, and the pseudostratified ciliated columnar epithelium covered the internal part of the thyroid and cricoid cartilages. Histomorphological studies showed a few goblet cells in the tracheal epithelium. In the bronchi and larger bronchioles, pseudostratified ciliated columnar epithelia were observed. Bronchi were surrounded by segments of cartilage. Distal bronchioles had a simple cuboidal/columnar epithelium with club (Clara) cells, lacked cartilaginous tissue in their walls and had a complete smooth muscle layer. These results revealed histomorphological differences between the ICP and other rodents.     

The analysis of <Emphasis Type="Italic">groEL</Emphasis> gene in <Emphasis Type="Italic">Salmonella enterica</Emphasis> subspecies <Emphasis Type="Italic">enterica</Emphasis> serovar Typhimurium isolated from avians by PCR-Restriction Fragment Length Polymorphism method

Salmonella enterica subspecies enterica serovar Typhimurium causes food-borne outbreaks and systemic diseases in humans and animals. groEL gene (also known as mopA gene in S. Typhimurium), possessing conserved sequence, plays an important role in invasion of bacteria. The purpose of present study was to identify the polymorphism of groEL gene among different avians in different regions by PCR-RFLP method. Fifty two S. Typhimurium isolates (Broiler (n = 13), Layer (n = 12), Duck (n = 5), Goose (n = 5), Sparrow (n = 8), Canary (n = 3), Pigeon (n = 5) and Casco parrot (n = 1). were identified using serotyping as well as multiplex-PCR. Then, amplification of groEL gene performed and amplified products subjected to restriction digestion with BsuRI enzyme. Three RFLP profiles, A, B and C, generated DNA fragments between approximately 100–1,000 bp in size, were observed. The RFLP profile A was observed in 35 (67.3%), profile B in 14 (26.9%) and profile C in 3 (5.77%) of isolates. S. Typhimurium isolates recovered from 13 broilers (two of which profile A, 9 profile B and 2 profile C) and from 8 sparrows (two of which profile A, 5 profile B and 1 profile C) showed all three profiles, but 12 layers and other avians (including Canary (n = 3), Goose (n = 5), Duck (n = 5), Pigeon (n = 5) and Casco parrot (n = 1)) showed profile A. None of these profiles was allotted for a special region. The result of present study showed that S. Typhimurium undergoes genetic mutations in groEL gene under unpleasant milieu in different regions and in different avians. Thus, genetic diversity, despite conserved nature of groEL gene in S. Typhimurium, may exist but it depends on the condition where bacteria have settled. To our knowledge, three RFLP profiles of groEL gene generated by BsuRI restriction enzyme were not reported previously.