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EN
This study was conducted to evaluate the influence of boron (B) application through seed coating on leaf elongation, tillering, water relations, panicle sterility, kernel yield, and grain biofortification of fine grain aromatic rice. Boron was applied as seed coating at 1.0, 1.5, 2.0, 2.5, and 3.0 g B kg-1 seed in two rice cultivars Super Basmati and Shaheen Basmati. Boron seed coating significantly affected the leaf elongation, water relations, panicle fertility, kernel yield and grain biofortification in both rice cultivars. However, seed coating with 1.0–2.0 g B kg-1 seed was effective in improving the leaf emergence and elongation, and tillering. Whereas water relations (water and osmotic potential) were improved by all B seed coating treatments, but pressure potential was only improved from seed coating with 2.0–3.0 g B kg-1 seed. Kernel yield was improved by all B seed coating treatments; however seed coating with 2 g B kg-1 seed was the most effective treatment in this regard. Increase in kernel yield, by B seed coating, was attributed to decrease in panicle sterility. Leaf and kernel B contents were increased with increase in B concentration in seed coating.
EN
Drought stress hampers rice performance principally by disrupting the plant–water relations and structure of biological membranes. This study appraised the role of polyamines (PAs) in improving drought tolerance in fine grain aromatic rice (Oryza sativa L.). Three PAs [putrescine (Put), spermidine (Spd) and spermine (Spm)] were used each at 10 µM as seed priming (by soaking seeds in solution) and foliar spray. Primed and non-primed seeds were sown in plastic pots with normal irrigation in a phytotron. At four-leaf stage, plants were subjected to drought stress by bringing the soil moisture down to 50% of field capacity by halting water supply. For foliar application, 10 µM solutions each of Put, Spd and Spm were sprayed at five-leaf stage. Results revealed that drought stress severely reduced the rice fresh and dry weights, while PAs application improved net photosynthesis, water use efficiency, leaf water status, production of free proline, anthocyanins and soluble phenolics and improved membrane properties. PAs improved drought tolerance in terms of dry matter yield and net photosynthesis was associated with the maintenance of leaf water status and improved water use efficiency. Among the antioxidants, catalase activity was negatively related to H₂O₂ and membrane permeability, which indicated alleviation of oxidative damage on cellular membranes by PAs application. Foliar application was more effective than the seed priming, and among the PAs, Spm was the most effective in improving drought tolerance.
EN
Environmental contamination, herbicide resistance development among weeds and health concerns due to over and misuse of synthetic herbicides has led the researchers to focus on alternative weed management strategies. Allelochemicals extracted from various plant species can act as natural weed inhibitors. In this study, allelopathic extracts from four plant species sorghum [Sorghum bicolor (L.) Moench], mulberry (Morus alba L.), barnyard grass [Echinochloa crusgalli (L.) Beauv.], winter cherry [Withania somnifera (L.)] were tested for their potential to inhibit the most problematic wheat (Triticum aestivum L.) weeds wild oat (Avena fatua L.) and canary grass (Phalaris minor Ritz.). Data regarding time to start germination, time to 50% germination, mean germination time, final germination percentage, germination energy, root and shoot length, number of roots, number of leaves, and seedling fresh and dry weight was recorded for both the weeds, which showed that mulberry was the most inhibitory plant species while sorghum showed least allelopathic suppression against wild oat. Mulberry extracts resulted in a complete inhibition of the wild oat germination. The allelopathic potential for different plants against wild oat was in the order: mulberry > winter cherry > barnyard grass > sorghum. Mulberry, barnyard grass and winter cherry extracts resulted in a complete inhibition of canary grass. Sorghum however exhibited least suppressive or in some cases stimulatory effects on canary grass. Plants revealing strong allelopathic potential can be utilized to derive natural herbicides for weed control.
PL
Skażenie środowiska, rozwój odporności na herbicydy wśród chwastów i przesłanki zdrowotne związane z nieprawidłowym używaniem herbicydów skłoniły badaczy do skoncentrowania się na alternatywnych strategiach zwalczania. Allelochemikalia uzyskane z różnych gatunków roślin mogą działać tak jak naturalne związki inhibujace chwasty. W przedstawionych badaniach testowano zdolność allelopatycznych wyciągów z czterech gatunków roślin sorgo, (Sorghum bicolor L., Echinochloa crusgalli (L.) Beauv., Withania somnifera L.), w celu określenia ich potencjału inhibicyjnego przeciwko stwarzającym problemy w pszenicy (Triticum aestivum L.) chwastom, mianowicie: Avena fatua L., Phalaris minor Ritz. Dane dotyczące czasu obejmującego okres przed początkiem kiełkowania, procent kiełkowania, czas potrzebny do skiełkowania 50% nasion, średni czas kiełkowania, końcowy czas kiełkowania, energię kiełkowania, długość korzeni i pędu, liczbę korzeni i liści, świeżą oraz suchą masę roślin, określono dla obydwóch gatunków chwastów, co wykazało, że morwa była najbardziej inhibującą rośliną, a sorgo wykazało najniższy stopień allelopatycznej supresji przeciwko A. fatua. Wyciągi z morwy powodowały całkowitą inhibicję kiełkowania A. fatua. Allelopatyczny potencjał różnych roślin przeciwko A. fatua był następujący: morwa > W. somnifera > E. crus-galli > sorgo. Jednak sorgo wykazało najmiej ograniczający albo w niektórych przypadkach stymulujący efekt na P. minor. Rośliny z silnym alelopatycznym potencjałem mogą być użyte do uzyskania naturalnych herbicydów zwalczających chwasty.
EN
The austenitic steel Sanicro 25 is one of the most promising austenitic steels for the application in superheater tubes in coal fired thermal power plants. In this work, the microstructural evolution of this material during heat treatment and thermal ageing has been investigated. The investigations were carried out by light microscopy (LIMI), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). Scheil calculations were carried out by thermo-kinetic software MatCalc to analyse the solidification process which indicates Nb(C,N), Cr2N and Laves phase in the melt. Long term precipitation calculations predict the formation of five precipitate types in Sanicro 25: M23C6, Z-phase, Nb(C,N), Laves and Cr2N. Phase fractions and mean radii evolution of precipitates were calculated and compared to the experimental results. Calculated precipitate evolution shows good compliance with experimental data.
PL
Stal austenityczna Sanicro 25 jest jedną z obiecujących stali do zastosowań na rury w wymiennikach ciepła w elektrowniach węglowych. W niniejszej pracy przeprowadzono badania rozwoju mikrostruktury podczas obróbki cieplnej i sztucznego starzenia tych stali. Badania wykonano za pomocą mikroskopu optycznego (LOM), skaningowego mikroskopu elektronowego (SEM), elektronowego mikroskopu transmisyjnego (TEM) i spektroskopu (EDS). Obliczenia metodą Scheila przeprowadzono wykorzystując oprogramowanie MatCalc. Analizowano proces krzepnięcia, w którym powstają fazy Nb(C,N), Cr2N oraz faza Lavesa. Obliczenia długoterminowego procesu wydzielania wykazały, że w Sanicro 25 powstaje 5 różnych faz: M23C6, faza-Z, Nb(C,N), faza Lavesa oraz Cr2N. Obliczone ułamki objętości poszczególnych faz oraz średni promień rosnących wydzieleń zostały porównane z wynikami doświadczeń i otrzymano dobrą zgodność.
EN
Sulphur (S) nutrition is very important for harvesting potential seed and oil yield of rapeseed. This study evaluated response of foliage applied thiourea on the performance of two canola cultivars Shiralee and Dunkeld. Sulphur was applied to soil (40 kg ha-1) or foliage (500 and 1,000 mg L-1) at rosette, bud initiation and flowering stages using elemental S or thiourea as source, respectively; no S application was taken as control. Among all the treatments, soil application of S improved the crop growth, yield and oil quality in both cultivars and was followed by foliar application of thiourea at 1,000 mg L-1 compared with no application. Soil applied S and foliar thiourea (1,000 mg L-1) delayed the flowering and maturity. Soil and foliar applied S significantly improved leaf area index, crop growth rate, net assimilation rate and chlorophyll contents. Plant height, number of branches, siliqua per plant, seed number per siliqua, 1,000-seed weight, biological and seed yield were also increased by soil applied S and foliage applied thiourea (1,000 mg L-1). Nonetheless, improvement in harvest index, seed oil, protein and glucosinolate contents was only observed from foliage applied thiourea (1,000 mg L-1). Response of cv. Shiralee to sulphur application was better than cv. Dunkeld. In conclusion, foliar applied thiourea (1,000 mg L-1) can have potential to improve growth, yield and oil quality in canola and can be economically viable and attractive alternative source.
EN
Tracer techniques, which are well-established methods in process dynamics studies in industry, were applied to investigate the dynamics of sewage treatment process. The concept of residence time distribution (RTD) was used to investigate the efficiency of the primary clarifier, aeration tank and secondary clarifier of a sewage treatment plant. Preliminary treatment and modeling of the tracer data was performed using the software DTS Pro Ver. 4.20. A big short - circuiting (by-passing) with a large volume of stagnant zones were found in the primary and secondary clarifiers, while no stagnant zone was detected in the aeration tank.
EN
This study was conducted to investigate the benefits associated with re-drying after seed priming with polyamines. Wheat (cv. AS-2002) seeds were soaked in 10 and 20 mg L⁻¹ aerated solutions of spermidine (Spd), putrescine (Put) and spermine (Spm), and distilled water (CK2) for 12 h at 28 ± 2°C. Untreated seeds (CK1) and priming in distilled water (CK2) were taken as control treatments. Seeds were primed in two sets: In one set, after each treatment, seeds were given three surface washings with distilled water and dried closer to original moisture; in the other, seeds were only surface dried and used immediately. Use of surface-dried seeds after priming was more effective since it reduced emergence time and synchronized the emergence. Moreover, final emergence, shoot and root length, seedling fresh and dry weight were also improved. Improved starch metabolism was considered possible reason of seed invigoration. All the seed treatments resulted in a lower electrical conductivity of seed leachates compared with control; however, there was more decrease in seeds re-dried after priming than the seeds surface dried after priming. Although the effect of all the polyamines was stimulatory, Spd was the more effective for most of the attributes studied. Nonetheless, Put was more effective for seedling fresh and dry weights. All the polyamines were more effective at lower concentrations except Spm, which improved the coefficient of uniformity of emergence at high concentration. To conclude, if immediate sowing is possible, use of surface-dried seeds after priming may be more effective; seed priming with 10 mg L⁻¹ Spd was the most effective technique when surface dried.
EN
In the current study, potential involvement of anthocyanins in the defence of the Zn hyperaccumulator plant, Noccaea caerulescens, was investigated in two independent glasshouse experiments. Plants were grown in compost amended with a range of Zn concentrations. In the first experiment, foliar herbivory was simulated by clipping the shoots with scissors, whilst in second experiment, plants were subjected to natural herbivory by thrips (Frankliniella occidentalis). In both experiments, foliar Zn concentrations were approximately twice as high as that applied to the soil, indicating accumulation occurred. In the clipping experiment, foliar anthocyanin concentrations decreased by 22–45 % with increasing soil Zn amendments and clipping increased anthocyanin concentrations by 17–24 % relative to unclipped plants. In a thrips feeding experiment, Zn treatment had little effect on anthocyanin content although there was a trend towards increased anthocyanin production in plants grown at the lower concentrations of Zn. Anthocyanin concentration increased by 49–52 % in N. caerulescens leaves subjected to thrip attack compared to that of thrip-free shoots. Thus, anthocyanins increased as a result of foliar damage (manual clipping and natural herbivory) and generally decreased with enhanced Zn concentrations. Foliar glucosinolate concentrations were higher in ungrazed leaves than in grazed leaves of the same thrip-infested plants, whilst anthocyanin production was higher in the grazed leaves. The possibility of an interaction between glucosinolate and anthocyanin production resulting from herbivory is discussed.
EN
Soil samples from petroleum-contaminated soil were collected from 25 different petroleum filling stations and automobile workshops in the district of Swat, Khyber Pakhtunkhawa, Pakistan. A total of seven bacterial genera were isolated. All of the isolates were Gram-positive bacteria. The genera identified by the culture and cell morphological characteristics were: Bacillus, Streptococcus, Staphylococcus, Micrococcus, Corynebacterium Arthrobacter, and Streptomyces. Lipolytic and saline activities of the selected isolates were studied. Among the isolates, Arthrobacter, Staphylococcus, Bacillus, Micrococcus, Corynebacterium, and Streptomyces produced lipase enzymes, while no lipase was produced by Streptococcus. Dense growth of Bacillus and Streptococcus was observed at 1% NaCl. Dense growth of Streptomyces was observed at strength of 2% NaCl. At 3% NaCl concentration, dense growth of Staphylococcus, Micrococcus, Corynebacterium, and Arthrobacter was observed, indicating that they were moderately halotolerent. In our study, Bacillus, Arthrobacter, and Streptomyces showed optimum growth at pH 8.0, and Streptococcus, Staphylococcus, and Micrococcus showed optimum growth at pH 7.0. Only Corynebacterium showed optimum growth at pH 9.0, indicating that it is tolerant of higher pH conditions.
EN
The indiscriminate use of herbicides has led to the contamination of water bodies, possibly affecting the health of aquatic biota, especially fish. Atrazine is considered as toxicants for aquatic fauna, due to its high persistence in soil, high half-life and high mobility toward aquatic bodies as well as high solubility in water. The objective of the present study was to determine (LC50) and to evaluate the acute and chronic toxicity of atrazine on the biochemical parameters; total protein and serum albumin of freshwater grass carp (Ctenopharyngodon idella). Above 15 μlL⁻¹, the LC50 was recorded revealing sensitivity of grass carp to atrazine. Grass carp was exposed to atrazine for 01 (15 μlL⁻¹), 02 (13 μlL⁻¹), 03 (10 μlL⁻¹), and 04 (08 μlL⁻¹) days/concentration for scrutinizing acute toxicity. Likewise, fish were exposed to atrazine for 10 (06 μlL⁻¹), 15 (04 μlL⁻¹), and 25 (02 μlL⁻¹) days/concentration for scrutinizing chronic toxicity. Control group concentration was 8.3 gL⁻¹ and 3.5 gL⁻¹. Total protein concentration observed for acute toxicity was 7.5 gL⁻¹, 6.5 gL⁻¹, 4.6 gL⁻¹, and 3.2 g/L and serum albumin concentration was 2.7 gL⁻¹, 1.6 gL⁻¹, 1.4 gL⁻¹, and 1.1 gL⁻¹ respectively. Similarly total protein concentration observed for chronic toxicity was 8.2 gL⁻¹, 6.8 gL⁻¹, and 4.3 gL⁻¹ and serum albumin concentration was 2.1 gL⁻¹, 1.7 gL⁻¹, and 1.4 gL⁻¹ respectively. Markedly decline (denoted by P<0.05, P≤0.01 and P≤0.001) was noticed in both the parameters concentration during acute as well as chronic toxicity, when compared with control group concentration, indicating negatively impinge of atrazine on grass carp as well as atrazine present in aquatic bodies must jeopardize the health of other aquatic fauna.
EN
The present study contemplates the enzymatic profile of grass carp, including lactate dehydrogenase (LDH), creatinine phosphokinases (CPK), serum glutamic-pyruvic transaminase (SGPT), and alkaline phosphatase (Alk Phosp) under atrazine’s acute toxicity effects (LC50) for 01 (15 μl/L), 02 (13 μl/L), 03 (10 μl/L), and 04 (08 μl/L) days/concentration, respectively. For analyzing the enzymatic profile we followed the biochemical analyzer set protocol (Merck micro lab 300 biochemistry analyzer) in the laboratory. Control group concentrations for LDH, CPK, SGPT, and Alk Phosp were 342 IU/ml, 7513.3 IU/ml, 46 mmol/l, and 126.6 IU/ml, respectively. After treatment LDH concentrations were 906, 851, 765, and 545 IU/ml, respectively. CPK concentrations were 1,737, 2,445, 3,718, and 5,767 IU/ml, respectively. SGPT concentrations were 27, 24.3, 13.67, and 8.67, respectively, and Alk Phosp concentrations were 50.3, 30, 22.3, and 17.6 IU/ml, respectively. Maximum inclined (P≤0.001) in concentration of LDH was observed after 24 hrs exposure because of hepatic tissue damage, resulting in increased membrane permeability causing enhanced leaching out of LDH and as LDH participates in an anaerobic pathway, so increase LDH mean increases of anaerobic metabolism resulting from depletion of energy under environmental stress conditions by atrazine, while other enzymatic components like CPK, SGPT, and Alk Phosp showed kindred attributes in their result, like all parameter concentrations showed perpetual decline (P≤0.001) in their concentrations indicating reduced enzymatic activity due to a reduction in permeability for these enzymes, forcing the enzymes to accumulate in the cells as well as decrease in enzyme synthesis due to intoxication of atrazine.
EN
Stratigraphical and sedimentological analyses of Late Neoproterozoic successions in Lesser Himalaya are combined herein with palaeogeographical considerations and comparisons with equivalent successions in India and South China. The succession starts with the Hazara Formation, which contains complete and incomplete Bouma sequences suggesting its deposition in deep marine turbidite settings. The overlying Tanawal Formation, rich in massive sandstone, shale and siltstone, was deposited in shallow marine conditions, as indicated by the presence of parallel lamination, large scale tabular, trough cross- and hummocky cross-stratifications. The Tanawal Formation facies shift laterally from proximal (south-southeast) to distal (north-northwest). The glaciogenic Tanaki Boulder Bed, overlying the Tanawal Formation, was deposited during the Maronian glaciation. It is equivalent to the Blaini Formation of India, and to the Sinian diamictites of South China. The Abbottabad Formation of Cambrian age overlies the Tanaki Boulder Bed, and is composed of dolomite, chert nodules and phosphate-rich packages; similar successions are documented in India and South China at the same stratigraphical interval. The similarities of the Neoproterozoic successions of Lesser Himalaya (both in Pakistan and India) and South China suggests their possible proximity during the break-up of Rodinia and the assembly of the Gondwana Supercontinent.
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