Significant Yield Variation Research Articles

RESPECT-ED: Rates of Pulmonary Emboli (PE) and Sub-Segmental PE with Modern Computed Tomographic Pulmonary Angiograms in Emergency Departments: A Multi-Center Observational Study Finds Significant Yield Variation, Uncorrelated with Use or Small PE Rates.

IntroductionOveruse of CT Pulmonary Angiograms (CTPA) for diagnosing pulmonary embolism (PE), particularly in Emergency Departments (ED), is considered problematic. Marked variations in positive CTPA rates are reported, with American 4–10% yields driving most concerns. Higher resolution CTPA may increase sub-segmental PE (SSPE) diagnoses, which may be up to 40% false positive. Excessive use and false positives could increase harm vs. benefit. These issues have not been systematically examined outside America.AimsTo describe current yield variation and CTPA utilisation in Australasian ED, exploring potential factors correlated with variation.MethodsA retrospective multi-centre review of consecutive ED-ordered CTPA using standard radiology reports. ED CTPA report data were inputted onto preformatted data-sheets. The primary outcome was site level yield, analysed both intra-site and against a nominated 15.3% yield. Factors potentially associated with yield were assessed for correlation.ResultsFourteen radiology departments (15 ED) provided 7077 CTPA data (94% ≥64-slice CT); PE were reported in 1028 (yield 14.6% (95%CI 13.8–15.4%; range 9.3–25.3%; site variation p <0.0001) with four sites significantly below and one above the 15.3% target. Admissions, CTPA usage, PE diagnosis rates and size of PE were uncorrelated with yield. Large PE (≥lobar) were 55% (CI: 52.1–58.2%) and SSPE 8.8% (CI: 7.1–10.5%) of positive scans. CTPA usage (0.2–1.5% adult attendances) was correlated (p<0.006) with PE diagnosis but not SSPE: large PE proportions.Discussion/ ConclusionsWe found significant intra-site CTPA yield variation within Australasia. Yield was not clearly correlated with CTPA usage or increased small PE rates. Both SSPE and large PE rates were similar to higher yield historical cohorts. CTPA use was considerably below USA 2.5–3% rates. Higher CTPA utilisation was positively correlated with PE diagnoses, but without evidence of increased proportions of small PE. This suggests that increased diagnoses seem to be of clinically relevant sized PE.

Variation in the straw traits of morphological fractions of faba bean (Vicia faba L.) and implications for selecting for food-feed varieties

Five varieties of faba beans, 4 improved and released variety and one local variety, were investigated for varietal variation in straw yield, nutritive value of straw morphological fractions and grain yield. Samples of the whole plant biomass were collected and separated into grain and straw. The straw was further divided into leaves, stems and pods. Straw samples were analyzed for their chemical composition, in vitro organic matter digestibility (IVOMD) and metabolizable energy (ME). The potential utility index (PUI) was employed to rank the varieties. The results demonstrated significant varietal variation in grain yield, straw yield and proportions of botanical fractions of straw. The improved varieties were superior to the local variety in grain yield, straw yield and PUI. The local variety had the highest proportion of stem and lowest proportion of leaf and pods. Significant varietal variations (P<0.001) were detected in dry matter (DM), organic matter (OM), ash, IVOMD, ME but not in crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) of whole straw. The leaves showed the highest IVOMD and content of crude protein, while pods were highest in ME. Canonical correlation analysis showed significant (P<0.001) correlations between the nutritive value of whole straw and nutritive value and proportions of its botanical fractions. Grain and straw yields were positively, strongly and significantly (P<0.001) correlated. Weak correlations were detected between grain yield and straw quality traits. Ranking the varieties differed when grain yield, straw quality scores and PUI were considered. However the weak correlation existed between grain yield and straw quality, including straw quality index or PUI to select food-feed varieties of faba bean is still necessary. These findings indicate the possibility of selecting faba bean varieties which combine superior grain and straw traits.

Enhancement of Copper Indium Gallium Selenide Solar Cells Using Europium Complex as Photon Downshifter

This work reports on the use of a ternary europium (III) complex as downshifting (DS) material for copper indium gallium selenide (CIGS) solar cells, [Eu(tta)3(tppo)2] (tta = 2‐thenoyltrifluoroacetonate and tppo = triphenylphosphine oxide). It is synthesized by one‐pot reaction and embedded into poly(ethylene‐co‐vinyl acetate) (EVA), poly(methyl methacrylate) (PMMA), and poly(vinyl butyral‐co‐vinyl alcohol‐co‐vinyl acetate) (PVB) matrices. Their photophysical properties are investigated and compared with the complex alone. No significant variations in transmittance, emission, excitation spectra, and quantum yield are detected between [Eu(tta)3(tppo)2] alone and embedded into EVA, PMMA, and PVB. CIGS solar cells are encapsulated using these compounds, leading to an improvement of the external quantum efficiency (EQE) mostly in UV region. The EQE at 360 nm increases up to 56% compared to 14% without the encapsulant. The luminescent downshifting (LDS) material is responsible for an increase in the short‐circuit current (Jsc) calculated from the EQE in the 300–420 nm region, by 0.55 mA cm−2 compared to the value of 0.59 mA cm−2 obtained from theoretical prediction. In the best case, an increase of the CIGS solar cell conversion efficiency by 0.8% absolute is observed thanks to the LDS material.

Influence of Harvest Cut Heights on Aroma profile of Ocimum basilicum L., O. kilimandscharicum Guerke and O. tenuiflorum L.

To find out the influence of harvesting height on essential oil yield and composition, three Ocimum species viz. O. basilicum L., O. kilimandscharicum Guerke and O. tenuiflorum L., were harvested at different heights in foothills agroclimatic conditions of north India. Three cut heights viz. top 1/3rd; top 2/3rd and whole plant were carried for the experiment in respective species and their chemotypes. The essential oil yield was reported to be higher in top 1/3rd harvested part of studied Ocimum spp. Altogether, 86 constituents, representing 89.2 - 99.9 % of the essential oil composition were identified by GC(RI) and GC-MS. Monoterpenoids (4.4 -90.4 %) and phenylpropanoids (61.4 -88.9 %) were the major class of constituents distributed in studied Ocimum spp. Significant variations in essential oil yield and composition, in terms of the content of marker constituents, were observed due to different harvesting heights in studied Ocimum spp.

Growth, yield, fruit quality and leaf nutrient status of grapefruit (Citrus paradisi Macf.): Variation from rootstocks

Present studies were made on ‘Marsh Seedless’ and ‘Redblush’ cultivars of grapefruit, budded on nine different rootstocks under the typical sub-tropical growing conditions of North India. Significant variations in tree vigour, fruit yield and quality and leaf nutrient concentrations were observed due to rootstock effects. For ‘Marsh Seedless’, ‘sour orange’ proved to be the most vigorous rootstock (45.88m3 canopy volume). Marsh Seedless budded on ‘Attani-2’ yielded best (29.15kgtree−1) with the fruits having high TSS (10.72°B), and highest contents of ascorbic acid (157.90mg 100g−1), phenol (128.43mgGAE−1 100g−1) and the activity of antioxidant (3.25μmol trolox g−1) with lowest acid content (0.92%). However, ‘Redblush’ cultivar while grown on ‘rough lemon’ showed vigorous growth (54.10m3 canopy volume). Rough lemon and ‘Attani-2’ proved high yielding rootstocks for ‘Redblush’ (25.80–28.92kgtree−1), and produced the fruits with highest ascorbic acid (105.17mg 100ml−1 juice) and lowest acid (1.01%) contents. The budding of ‘Redblush’ on ‘Billikhichli’ yielded the fruits with highest TSS (12.65°B) and phenol (92.80mgGAE−1 100g−1) contents and the highest antioxidant activity (3.70μmol trolox g−1). Besides, ‘Attani-2’ also enhanced the nutrients accumulation in ‘Marsh Seedless’ (P, K, Cu and Fe) and ‘Redblush’ (N, P, Ca, Mn and Fe). ‘Rough lemon’ as a rootstock also improved the nutrient accumulation in ‘Redblush’ (P, K, Mg and Mn). Yield showed the significant correlations with peel thickness (r=0.582) and titratable acidity (r=−0.706). Growth, yield and fruit quality (TSS and Titratable acidity) of grapefruits were significantly influenced by seasonal variation. Overall, ‘sour orange’ for ‘Marsh Seedless’ and ‘rough lemon’ for ‘Redblush’ proved most vigorous. ‘Attani-2′ proved promising to achieve high yield of best quality fruits of ‘Marsh Seedless’, while high yield of ‘Redblush’ was obtained on either ‘Attani-1’ or ‘rough lemon’, with ‘Billikhichli’ being best for producing high quality fruits. “Attani-2’ proved a good Na excluder rootstock for both the cultivars too.

Screening out of wheat varieties against arsenic contaminated soil and irrigation water

Field trials on wheat were conducted at severely arsenic contaminated areas of Jessore (Chowgacha and Sharsha), Faridpur (Poranpur) and also at low contaminated Shatkhira (Benerpota) during 2010-2011 and 2011-12. The major objective of the study was to screening out of arsenic tolerant wheat varieties. Five varieties of wheat viz. Shatabdi, Bijoy, Prodip, BARI Gom-25 and BARI Gom-26 were tested. Total arsenic contents in the soils were 36.4, 32.8, 28.5 and 6.8 mg kg-1 for Sharsha, Chowgacha, Poranpur and Benerpota, respectively. Irrigation waters contained 0.346, 0.272, 0.238 and 0.140 mg L-1 arsenic for Sharsha, Chowgacha, Poranpur and Benerpota, respectively. No significant variations in yield and yield components among the tested wheat varieties was observed despite of arsenic contaminations in the irrigation water and soil. The variety, Prodip contains 0.043 and 0.028 mg kg-1 arsenic in straw and grain, respectively, which was lower than the other tested varieties. But arsenic contents in all of the tested wheat varieties were found much lower than that of the permissible limit (1 mg kg-1). The transfer coefficient (TC) of arsenic from soil to above ground parts (straw + grain) of wheat varied slightly among the tested varieties where Prodip showed the lowest TC (0.0015-0.0018). However, BARI Gom-24 (Prodip) performed better in terms of arsenic content, uptake, biomass, yield and transfer coefficient and thus can be regarded as arsenic tolerant to a considerable extent.J. Asiat. Soc. Bangladesh, Sci. 42(1): 1-11, June 2016

A Comparative Study of Vermicompost Prepared from Phytoremediated and Naturally Grown Aquatic Weeds on Growth and Yield of Green Gram [Vigna radiata (L.) Wilczek

The present investigation was carried out to compare the effect of vermicompost prepared from lead phytoremediated aquatic weeds and naturally reared aquatic weeds on the growth and yield of green gram [Vigna radiata (L.) Wilczek] under potted conditions in the Botanical garden of Utkal University. Vermicompost was prepared from cow-dung and aquatic weeds namely Azolla microphylla, Pistia stratiotes, Salvinia cucullata and Salvinia molesta by using earthworms (Perionyx excavatus). The pot experiment was conducted with nine treatments each having three replicates i.e. control (C), Azolla vermicompost (AV), treated Azolla vermicompost (TAV), Pistia vermicompost (PV), treated Pistia vermicompost (TPV), Salvinia cucullata vermicompost (S.cuV), treated Salvinia cucullata vermicompost (TS.cuV), Salvinia molesta vermicompost (S.mV), treated Salvinia molesta vermicompost (TS.mV).The test aquatic plants were used for phytoremediation with 50 ppm Pb (NO3)2 solution. The results of the present experiment indicated a significant variation in plant growth and yield of green gram, physico-chemical properties and heavy metal (Pb) content of different vermicompost samples. The Pb concentration in the vermicompost samples were found within the permissible limit i.e. below 100 mg/kg. The highest bioaccumulation of Pb was observed in treated Azolla-vermicompost sample (98.9mg/kg) and lowest in non-treated Pistia-vermicompost (8.10mg/kg). The significant variation in the growth parameters of the test crop such as plant height, number of shoots and root branches, number of leaves and flowers per plant, number of pods per plant, pod length as well as number of root nodules per plant were recorded on 15th day, 30th day, 45th day and 60th day of sowing seeds. The maximum value of growth parameters was claimed when grown with amendments of AV followed by PV and SV. Compared to other treatments, Azolla vemicomposting (AV) was proved to be the best one for the test crop under study. Analysis of biochemical properties of the prepared vermicomposts revealed that they can play a major role in the growth and development of green gram. The present investigation also confirmed the process of conversion of phytoremediated aquatic weed biomass into vermicompost thereby indicating their ability for an ecofriendly technology in sustainable agriculture. The study also revealed the way for management of the rapid growth of aquatic weeds by utilizing them for bioremediation as well as the production of vermicomposts

Effect of polluted river water on growth, yield and heavy metal accumulation of red amaranth

The present study was carried out to assess the levels of different heavy metals like chromium (Cr), lead (Pb), cadmium (Cd), iron (Fe), copper (Cu), zinc (Zn) and manganese (Mn) on red amaranth vegetable irrigated with polluted river water. Atomic Absorption Spectrometer was used for analyzing the heavy metals in the samples. The results indicated a substantial build-up of heavy metals accumulation in red amaranth irrigated with polluted river water. The ranges of various metals in red amaranth samples irrigated with polluted river water were 0.45–0.93, 0.147–0.175, 42.33–479.73, 1.31–12.04, 3.71–35.11 and 10.9–142.9 ?g g-1 for Cr, Pb, Fe, Cu, Zn and Mn, respectively. Cadmium concentration was below the detection limit (0.01 ?g g-1) of the method used in the analysis. However, the regular monitoring of levels of these metals from effluents and sewage, in vegetables and in other food materials is essential to prevent excessive build-up of these metals in the food chain. In general, our results indicated that using polluted river water had no significant variation in growth and yield of red amaranth from the crops irrigated with fresh water.Res. Agric., Livest. Fish.3(1): 53-65, April 2016

Mitigation of the adverse effects of soil salinity in rice using exogenous proline and organic manure

Salinity causes cellular damage and limits crop productivity. Accumulation of organic compound is one of the major adaptive mechanisms for salinity tolerance in plants. The main objective of the present study was to mitigate the adverse effects of soil salinity in rice through organic amendments like proline and organic manure. The field experiments were conducted at the farmer’s field of Batiaghata upazilla under Khulna district with aman rice. The soil was silty clay loam having pH 7.2, EC 6.6 dS/m, CEC 26 meq/100 g soil and organic matter 0.84%. Rice variety BR 23 was used as a test crop. There were 15 treatment combinations with different doses of proline and organic manures. Recommended doses of N, P, K, S and Zn fertilizers were applied to all the experimental plots. Proline was applied as foliar spray at seedling and/or vegetative stages. Organic manures were added to soils during final land preparation. The experiments were laid out in a randomized complete block design with three replications. Significant reductions in growth and yield of rice were observed under saline conditions. Application of both proline and organic manures significantly increased growth, yield contributing characters, and grain and straw yields of rice under salinity conditions. There were no significant variations in growth and yield of rice due to use of different doses of proline and organic manure. Increased nutrient uptake and K+/Na+ ratio were observed in rice due to proline as well as organic manure application under saline conditions. The present study suggests that exogenous proline or organic manure confers tolerance to salinity in rice by increasing K+/Na+ ratio and nutrient uptake.Asian J. Med. Biol. Res. December 2015, 1(3): 478-486

Growth, yield and important quality attributes chilli (Capsicumsp.) genotypes under the Sub Himalayan tracts of West Bengal

An experiment was undertaken to study the performance of 65 chilli genotypes during the rabi (i.e. winter) season 2005–06 and 2006–07. Mean performance revealed significant variation in yield and quality characters among the different genotypes. Maximum green fruit yield was recorded in CA-29 (262.25 g/plant), which was statistically at par with CA-47 (244.89 g/plant). Higher yield was also recorded in CA-34 (233.38 g/plant), CA48 (232.62 g/plant), CA-30 (230.27 g/plant) and CA-40 (219.89 g/plant). Ascorbic acid content in green fruit varied from 74.78 to 168.10 mg/100 g fresh. The highest capsaicin content in green fruit was recorded in CA60 (2.08%) the lowest in CA-55 (0.19%). Highest amount of extractable colour in red ripe fruit was recorded in CA-55 (185.34 ASTA) followed by Utkal Abha (156.31 ASTA).

The incremental impact of cardiac MRI on clinical decision-making

Despite a significant expansion in the use of cardiac MRI (CMR), there is inadequate evaluation of its incremental impact on clinical decision-making over and above other well-established modalities. We sought to determine the incremental utility of CMR in routine practice. 629 consecutive CMR studies referred by 44 clinicians from 9 institutions were evaluated. Pre-defined algorithms were used to determine the incremental influence on diagnostic thinking, influence on clinical management and thus the overall clinical utility. Studies were also subdivided and evaluated according to the indication for CMR. CMR provided incremental information to the clinician in 85% of cases, with incremental influence on diagnostic thinking in 85% of cases and incremental impact on management in 42% of cases. The overall incremental utility of CMR exceeded 90% in 7 out of the 13 indications, whereas in settings such as the evaluation of unexplained ventricular arrhythmia or mild left ventricular systolic dysfunction, this was <50%. CMR was frequently able to inform and influence decision-making in routine clinical practice, even with analyses that accepted only incremental clinical information and excluded a redundant duplication of imaging. Significant variations in yield were noted according to the indication for CMR. These data support a wider integration of CMR services into cardiac imaging departments. These data are the first to objectively evaluate the incremental value of a UK CMR service in clinical decision-making. Such data are essential when seeking justification for a CMR service.

Extent of central neck dissection among thyroid cancer surgeons: Cross-sectional analysis.

It is unclear if surgeons are performing comprehensive central neck dissections for well-differentiated thyroid cancer. The purpose of this study was to determine mean lymph node retrieval in central neck dissection as well as variability across surgeons and institutions. A prospectively collected database identified 18 surgeons performing 425 central neck dissections, 313 unilateral and 112 bilateral. Demographics, perioperative, and pathologic factors were analyzed. Mean lymph node yield was 7.4 and 11.9 for unilateral and bilateral central neck dissection, respectively. Although 224 central neck dissections were prophylactic, both total and pathologic lymph node yields were significantly higher in therapeutic central neck dissection. There was a significant variation in lymph node yield across individual surgeons, institutions, and regions. High-volume central neck dissection surgeons have significantly lower lymph node yield compared to low-volume surgeons. Central neck dissection seems to be performed adequately; however, there is a significant variation in lymph node yield. Future initiatives should try to standardize the central neck dissections performed, with emphasis on obtaining a sufficient yield. © 2015 Wiley Periodicals, Inc. Head Neck 38: E328-E332, 2016.

A comparison of DNA extraction methods for biodiversity studies of eukaryotes in marine sediments

There is increasing interest in understanding the diversity of eukaryotic microorgan- isms living in marine sediments, particularly to assess the effects of anthropogenic activities. Sequencing technologies generate high-resolution data for biodiversity studies that are useful for environmental monitoring. However, there are challenges in coupling classical monitoring with new sequencing technology and, consequently, there is a requirement for stringent optimization and standardization of any new protocol. Sample preparation is a critical factor because errors introduced during this step will severely affect further analyses and conclusions. This is particu- larly important in studies where biodiversity between different samples is compared, such as in environmental monitoring programs. Several protocols for extracting genomic DNA from soil and sediment samples have been developed, but most are optimized for prokaryotes in terrestrial soils and may therefore not be optimally adapted for investigating benthic marine eukaryotes. In this study, we compared existing and modified genomic DNA extraction methods on 2 different mar- ine sediments with the aim to find an optimal protocol for processing a high number of sediment samples for further sequencing analysis. The protocols were evaluated based on quantity and quality of genomic DNA and recovered biodiversity. Results indicated significant variations in overall genomic DNA yield and purity among protocols. Further, our data suggest an effect of genomic DNA extraction procedure on eukaryotic diversity profiles, particularly for sediments with a high content of silt and clay.

First vs. second rotation of a poplar short rotation coppice: Above-ground biomass productivity and shoot dynamics

Within the global search for renewable energy sources, woody biomass from short rotation coppice (SRC) cultures is a valuable option. So far there is a shortage of large-scale field yield data to support stakeholders. We investigated an operational-scale SRC plantation (POPFULL) with 12 poplar genotypes in Flanders during its first two biennial rotations. By inventorying shoot numbers and diameters, combined with allometric relationships, productivity related data were derived after each growing season. We observed significant variation in biomass yield and productivity-related characteristics among the 12 poplar genotypes, of which two recently selected. Genotype Hees (Populus deltoides × Populus nigra) and Skado (Populus trichocarpa × Populus maximowiczii, selected in 2005) reached the highest productivity among genotypes, i.e. 16 Mg ha−1 y−1 of dry matter (DM) yield in the second rotation, which was more than double than the poorest performing genotype Brandaris (a pure P. nigra). However, with many small shoots genotype Hees had a different growth strategy than Skado that resprouted with few, thicker and higher shoots. Biomass production increased from a plantation average of 4.04 Mg ha−1 y−1 of DM in the first (establishment) rotation to 12.24 Mg ha−1 y−1 in the second rotation. Mean height growth raised from 2.08 m y−1 during the first rotation to 2.99 m y−1 during the second rotation. The influence of the first coppicing on tree mortality was negligible. Monitoring of subsequent rotations over the plantations' lifetime – which counts for SRC bioenergy cultures in general – is essential to evaluate productivity in the long term.

Performance of papaya cultivars grown under protected conditions

Papaya is an important fruit crop of tropical region. However, it can be grown successfully in the sub-tropical regions of north India with suitable precautions. The major limitations in papaya cultivation on commercial scale in Punjab include dioecious nature of varieties, extremes of temperature, frost, water-logging causing wilt and susceptibility to viral diseases (leaf curl and mosaic). These problems can be managed to some extent by growing plants under protected conditions. In the present study, plants of five papaya varieties, namely, Surya, Madhu, Arka Prabhath, Pusa Dwarf and Red Lady 786 were evaluated under poly-nethouse in 2012 and analysed for yield and various physico-chemical fruit traits. The results revealed significant variations in fruit number (20.47–46.00), yield (10.49–38.84 kg), fruit weight (508.00–841.67 g), TSS (8.0–13.0%) and total sugars (3.0–7.9%). However, no significant variations were observed in terms of edible portion, fruit firmness and titrable acidity. The highest yield (38.84 kg) and best fruit quality traits in terms of fruit weight (841.67 g), TSS (13.0%) and total sugars (7.9%) were found in the variety Red Lady 786.

Evaluation of Different Maturity Groups of Soybean (Glycine Max L. Merrill) Grown Sole and Intercropped with Maize (Zea Mays L.) for Yield and Yield Components at Bako, Ethiopia

Different maturity of soybean genotypes interact differently either in sole or intercropping system. Therefore, screening of the genotypes under various environment is paramount important for variety recommendation. The experiment was conducted to evaluate different soybean genotypes in intercropping and sole cropping systems. Fifteen genotypes were evaluated in using randomized complete block design with three replications. The result revealed nodule number and plant height was significantly affected by genotypes variation in both systems. A total of 32-73% reduction in nodule number was recorded when compared with soles due to shading of maize. However, late and early types had higher number of nodules as opposed to medium type. Late type was generally taller than early and medium ones. Significant differences in grain yield were also recorded in both systems. But maize shading effect considerably reduced the yield though population difference is also another factor. Promoveria (3826 kg ha-1), IAW-13-1(3747 kg ha-1) and Pr-145-2-1 (3620 kg ha-1) genotypes resulted the highest grain yield and productivity, while the lowest yield was obtained from Pr-145-2 (2144 kg ha-1) when grown in soles. However, IAW-13-1 (690 kg ha-1) and AGX-129-2 (672 kg ha-1) produced the highest grain yield in intercropping systems. Comparing each maturity groups, significant variation both in nodule number and grain yield was also recorded. As general, most of the tested genotypes that were performed well in intercropping were not so far released. AGS-129-2 genotype was released recently in sole cropping systems, but now it is also well performed in intercropping systems. For unreleased pipelines it is important to consider as variety verification trial to confidently recommend for the end users.

Water budgeting in a carp-prawn polyculture system: impacts on production performance, water productivity and sediment stack

This study was designed to quantify the total water requirement and consumptive water use in carp-prawn polyculture system under different water management protocols, using water balance model. Under different water management protocols, treatment-wise estimated total water use, TWU (×104, m3) was 3.7, 4.6 and 3.9, while the computed consumptive water use index, CWUI (m3 kg−1 biomass) was 6.62, 9.31 and 7.08, in T1 (no water exchange), T2 (periodic water exchange) and T3 (regulated water exchange) respectively. Significantly higher yield (P < 0.05) in both T2 and T3 over T1, was probably due to water exchange that improved the rearing environment. Although intensity of water exchange was more in T2, significant variation (P < 0.05) in overall growth and yield was not recorded between T2 and T3. Treatment-wise sediment load ranged between 54.6 and 71.3 m3 t−1 biomasses. Higher sediment load was recorded at lower intensity of water exchange as well as with higher apparent feed conversion ratio. Higher net total water productivity, net consumptive water productivity and OV-CC ratio in T3 infers that regulated water exchange has a distinct edge over the no water exchange protocol. Restricted water use instead of regular/excess water exchange not only improves the production performance and water productivity, but also helps in lessening the operational pumping cost.

Interference and economic threshold level of little seed canary grass in wheat under different sowing times

Little seed canary grass (LCG) is a pernicious weed of wheat crop causing enormous yield losses. Information on the interference and economic threshold (ET) level of LCG is of prime significance to rationalize the use of herbicide for its effective management in wheat fields. The present study was conducted to quantify interference and ET density of LCG in mid-sown (20 November) and late-sown (10 December) wheat. Experiment was triplicated in randomized split-plot design with sowing dates as the main plots and LCG densities (10, 20, 30, and 40 plants m(-2)) as the subplots. Plots with two natural infestations of weeds including and excluding LCG were maintained for comparing its interference in pure stands with designated densities. A season-long weed-free treatment was also run. Results indicated that composite stand of weeds, including LCG, and density of 40 LCG plants m(-2) were more competitive with wheat, especially when crop was sown late in season. Maximum weed dry biomass was attained by composite stand of weeds including LCG followed by 40 LCG plants m(-2) under both sowing dates. Significant variations in wheat growth and yield were observed under the influence of different LCG densities as well as sowing dates. Presence of 40 LCG plants m(-2) reduced wheat yield by 28 and 34% in mid- and late-sown wheat crop, respectively. These losses were much greater than those for infestation of all weeds, excluding LCG. Linear regression model was effective in simulating wheat yield losses over a wide range of LCG densities, and the regression equations showed good fit to observed data. The ET levels of LCG were 6-7 and 2.2-3.3 plants m(-2) in mid- and late-sown wheat crop, respectively. Herbicide should be applied in cases when LCG density exceeds these levels under respective sowing dates.

Compositions and yield variation of essential oils among and within nine Salvia species from various areas of Iran

The compositions of essential oils of 22 accessions belonging to nine Salvia species of Salvia nemorosa, Salvia sclarea, Salvia macrosiphon, Salvia verticillata, Salvia eremophilsamia, Salvia aethiopis, Salvia virgata, Salvia reuterana and Salvia limbata, from Iran were assessed. The concentration of essential oil yield obtained by hydrodistillation ranged from 0.07 to 0.71%. GC–MS analysis revealed 73 compounds in these plants. The main constituents were linalool (0.6–51.58%), linalool acetate (0–52.61%), e-caryophylene (3.08–60.58%), germacrene-d (0–25.16%) spathulenol (0–35.4%) and caryophyllen-oxide (0–37.89%). The accessions were separated into five chemotypes using cluster analysis in light of the six major compositions. Results showed a significant variation in compositions and yield of essential oils among and within Salvia species. The chemical variability could be attributed to genetic and environmental factors. The analyses indicated that some of accessions collected from south had more amounts of essential oils yield than other regions.

Membrane biofouling characterization: effects of sample preparation procedures on biofilm structure and the microbial community

Ensuring the quality and reproducibility of results from biofilm structure and microbial community analysis is essential to membrane biofouling studies. This study evaluated the impacts of three sample preparation factors (ie number of buffer rinses, storage time at 4°C, and DNA extraction method) on the downstream analysis of nitrifying biofilms grown on ultrafiltration membranes. Both rinse and storage affected biofilm structure, as suggested by their strong correlation with total biovolume, biofilm thickness, roughness and the spatial distribution of EPS. Significant variations in DNA yields and microbial community diversity were also observed among samples treated by different rinses, storage and DNA extraction methods. For the tested biofilms, two rinses, no storage and DNA extraction with both mechanical and chemical cell lysis from attached biofilm were the optimal sample preparation procedures for obtaining accurate information about biofilm structure, EPS distribution and the microbial community.