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Many agricultural soils fail to supply sufficient boron (B) and phosphorus (P) to growing plants due to their adsorption, precipitation and fixation phenomena. Moreover, the application of individual B sources without a macronutrient fertilizer is impractical owing to the separate handling and poor distribution in the field. The study aimed to develop and compare the efficiency of organically complexed boron-diammonium phosphate (B-DAP) formulations with commercial diammonium phosphate (C-DAP) and boric acid for improving yield and oil content of canola. To prepare 0.5, 1 and 1.5% B-DAP formulations, PGPR-impregnated pressmud containing 1% B (slurry) was coated on C-DAP to achieve slurry to P2O5 ratio as 0.5:1, 1:1 and 1.5:1, respectively. Treatments tested in incubation, pot and field studies were C-DAP130, C-DAP130 + B2.5, and 0.5%, 1% and 1.5% B-DAP; each B-DAP formulation was added to supply 98 and 130 kg P2O5 ha−1. The results of the incubation study depicted that with the application of 1.5% B-DAP130 available P content increased by 51% between 2 and 10 weeks of incubation. Likewise, soils fertilized with B-DAP98 and B-DAP130 had significantly (p

Low use efficiency of nitrogen (N) and phosphorus (P) is major challenge of modern agriculture. Coating of conventional fertilizers with nanomaterials is a promising technique for improved nutrient use efficiency. In current study, nanoparticles (NPs) of potassium ferrite (KFeO2 NPs) were coated on di-ammonium phosphate (DAP) fertilizer with three rates (2, 5, 10%) of KFeO2 NPs and were evaluated for release of N, P, K and Fe supplementation in clay loam and loam soil up to 60 days. The NPs were characterized for crystal assemblage, bond formation, morphology and configuration using the x-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform-infra red spectroscopy (FT-IR). The results showed that size of NPs ranged between 7 and 18 nm. The controlled release of P in 10% KFeO2 nano-coated DAP was observed throughout the incubation period. The P release kept on increasing from day-1 (14.5 µg g−1) to day-60 (178.6 µg g−1) in coated DAP (10%) in loam soil. The maximum release of 50.4 µg g−1 NH4+1-N in coated DAP (10%) was observed after 30 days of incubation. The release of NO3−1-N was consistent up to 45 and 60 days in clay loam and loam soil, respectively. The average release of potassium and iron in 60 days was 19.7 µg g−1 and 7.3 µg g−1 higher in 10% coated DAP than traditional DAP in clay loam soil. It was concluded that KFeO2 nano-coated DAP supplied P and mineral N for longer period of time in both soils, and some higher coating levels should be tested in future.

To improve sustainability of polymers and to reduce carbon footprint, polymers from renewable resources are given significant attention due to the developing concern over environmental protection. The renewable materials are progressively used in many technical applications instead of short-term-use products. However, among other applications, the flame retardancy of such polymers needs to be improved for technical applications due to potential fire risk and their involvement in our daily life. To overcome this potential risk, various flame retardants (FRs) compounds based on conventional and non-conventional approaches such as inorganic FRs, nitrogen-based FRs, halogenated FRs and nanofillers were synthesized. However, most of the conventional FRs are non-biodegradable and if disposed in the landfill, microorganisms in the soil or water cannot degrade them. Hence, they remain in the environment for long time and may find their way not only in the food chain but can also easily attach to any airborne particle and can travel distances and may end up in freshwater, food products, ecosystems, or even can be inhaled if they are present in the air. Furthermore, it is not a good choice to use non-biodegradable FRs in biodegradable polymers such as polylactic acid (PLA). Therefore, the goal of this review paper is to promote the use of biodegradable and bio-based compounds for flame retardants used in polymeric materials.

Thermoplastic processing and spinning of native starch is very challenging due to (a) the linear and branched polymers (amylose and amylopectin) present in its structure and (b) the presence of inter-and-intramolecular hydrogen bond linkages in its macromolecules that restrict the molecular chain mobility. Therefore, in this study, oxidized starch (OS) (obtained after oxidation of native starch with sodium perborate) was melt-blended with polylactic acid (PLA) polymer to prepare PLA/OS blends that were then mixed together with ammonium polyphosphate (APP), a halogen-free flame retardant (FR) used as acid donor in intumescent formulations on twin-screw extruder to prepare PLA/OS/APP composites. OS with different concentrations also served as bio-based carbonic source in intumescent formulations. PLA/OS/APP composites were melt spun to multifilament fibers on pilot scale melt-spinning machine and their crystallinity and mechanical properties were optimized by varying spinning parameters. The crystallinity of the fibers was studied by differential scanning calorimetry and thermal stabilities were analyzed by thermogravimetric analysis. Scanning electron microscopy was used to investigate the surface morphology and dispersion of the additives in the fibers. Needle-punched non-woven fabrics from as prepared melt-spun PLA/OS/APP fibers were developed and their fire properties such as heat release rate, total heat release, time to ignition, residual mass % etc. by cone calorimetry test were measured. It was found that PLA/OS/APP composites can be melt spun to multifilament fibers and non-woven flame-retardant fabrics produced thereof can be used in industrial FR applications.

Biodegradable polymers from renewable resources have attracted interest due to environmental pollution caused by the disposal of non-degradable polymers, and engineering them to produce fibres of textile grade can improve the environmental sustainability of textile sector. Flame retardancy of polylactic acid (PLA) can be improved if used in intumescent system containing acidic and carbonic source; however, spinning them to produce fibres of textile grade is a big challenge. We therefore have prepared PLA composites containing phosphorous-nitrogen-based flame retardant as acidic source together with kraft lignin as carbonic source. Different quantities of flame retardant and kraft lignin were added to PLA matrix by melt blending and then hot-pressed to form moulding sheets. A modified polyester-based plasticizer was also incorporated to facilitate the spinnability of the composites. Limiting oxygen index values and UL-94 ratings of the composites were reported. The melt spinnability of composites was then assessed, and flame retardancy of knitted structures produced from multifilament yarns was tested by cone calorimetry. Composites containing up to 7% (m/m) of lignin were spinnable together with 10% (m/m) of plasticizer. A substantial decrease of 59% in heat release rate was observed compared to pure PLA. The mechanism of intumescence was also reported.

Polymeric materials play an important role in our daily life due to their vast application range. However, flame retardancy of such polymers needs to be improved for technical applications due to potential fire risk they possess. Most of the conventional flame-retardants are not biodegradable and if disposed in the landfill, microorganisms in the soil or water cannot degrade them. Hence, they remain in the environment for long time and may find their way not only in the food chain but can also easily attach to any airborne particle and can be toxic for environment and human life. Therefore, the goal of this research work is to promote the use of biodegradable and biobased compounds for flame-retardant applications. Therefore, for this dissertation biobased and biodegradable intumescent flame-retardants for Polylactic acid textiles and composites were developed. A remarkable increase in flame-retardancy in the developed textiles and a significant decrease in heat release rate, total smoke production and effective heat of combustion in composites were observed. The developed products achieved the benchmark properties as defined by EN ISO 11925-2 standard testing method, which certifies the commercial application of this product. Hence, the results in this dissertation confirmed that biodegradable and biobased additives can be used in technical flame-retardant applications with comparable properties to conventional non-biodegradable flame-retardants.

Silicon is known to improve resistance against salinity stress in maize crop. This study was conducted to evaluate the influence of silicon application on growth and salt resistance in maize. Seeds of two maize genotypes (salt-sensitive ‘EV 1089’ and salt-tolerant ‘Syngenta 8441’) were grown in pots containing 0 and 2 mM Si with and without 50 mM NaCl. After detailed investigation of ion concentrations in different maize organs, both genotypes were further selected in hydroponic experiment on basis of their contrasting response to salinity stress. In the second experiment, pre-germinated seedlings were transplanted into nutrient solution with 0 and 60 mM NaCl with and without 2 mM Si. Both genotypes differed significantly in their response to salinity. Silicon addition alleviated both osmotic and oxidative stress in maize crop by improving the performance of defensive machinery under salinity stress. Silicon application also improved the water-use efficiency in both tested genotypes under both normal and salinity stress conditions. In conclusion, this study implies that the silicon-treated maize plants had better chance to survive under salinity conditions and their photosynthetic and biochemical apparatus was working far better than that of silicon-non-treated plants.

Polylactic acid (PLA) is a biodegradable and compostable polymer obtained from annually renewable resources and is acknowledged to be sustainable and eco-friendly polymer with substantial commercial prospective as a textile fiber however, this polymer has not been investigated much in apparel applications. Therefore in this study it was aimed to develop biobased compostable socks from PLA draw textured melt spun yarns and to examine the effect of yarn linear density, fabric structure and stitch density on thermo-physiological characteristics of PLA based socks. 100% PLA based multifilament yarns of two different linear densities were melt spun and later draw textured on false twist texturing machine to be used for socks knitting. Single jersey and rib structures were produced with two different stitch densities to investigate their effect on thermal resistance, relative water vapour permeability, thermal conductivity, vertical wicking and air permeability of the socks. Minitab statistical software was employed to analyze the results of test samples. The coefficients of determinations (R-2 values) presented good estimation capability of the established regression models. The outcomes of this research may be useful in determining suitable manufacturing requirements of PLA based socks to accomplish precise thermo-physiological properties. (C) 2018 Elsevier Ltd. All rights reserved.

Background: The Pakistani Salt Range has a rich floral diversity including Withania coagulans from the Solanaceae family. Methods: The crude methanolic extracts of the root, leaf, leaf stalk, and fruit of this plant were screened for their cytotoxic activity against human (HeLa, MCF-7, RD) and rat (RG2 and INS-1) cancer cell lines at 20 μg/mL and compared to methotrexate. The IC50 values indicated that leaf stalk and fruit extracts exert an 80% or higher cytotoxic activity against all cell lines at 24 hours. Results: The leaf stalk extract showed the highest cytotoxic efficacy against all tested cell lines, with IC50 values ranging from 0.96 ± 0.01 μg/mL to 4.73 ± 0.05 μg/mL followed by the fruit extract with IC50 values of 0.69 ± 0.01–6.69 ± 0.06 μg/mL after 48–72 hours incubation. The leaf stalk and seed extracts were analyzed for polyphenols and flavonoids using RP-HPLC. The total flavonoid content (TFC) was calculated for all tested samples, and the highest TFC was recorded for the root extract (394.34 ± 1.26 μg/g). The total phenolic content (TPC) was found in the seed extract (307.86 ± 9.42 μg/g) of W. coagulans. The highest contents of myricetin (358.46 ± 2.91 μg/g) were noted in the leaf extract, and highest quercetin was recorded in the seed extract (21.43 ± 0.13 μg/g). The highest gallic acid concentration (83.62 ± 0.71 μg/g) was recorded in leaf stalk extract and p-hydroxybenzoic acid in the seed extract (157.46 ± 1.43 μg/g). Conclusion: The present study gives a scientific insight and comparative analysis of various plant parts in this medicinally important plant species from the Salt Range of Pakistan against both human and rat cancer cells. Keywords: Anticancer, Presto Blue cell metabolic assay, Total phenolic contents, Total flavonoid contents

Cadmium (Cd) accumulation in agricultural soils is one of the major threats to food security. The application of inorganic amendments such as mono-ammonium phosphate (MAP), gypsum and elemental sulfur (S) could alleviate the negative effects of Cd in crops. However, their long-term residual effects on decreasing Cd uptake in latter crops remain unclear. A field that had previously been applied with treatments including control and 0.2, 0.4 and 0.8% by weight of each MAP, gypsum and S, and grown with wheat and rice and thereafter wheat in the rotation was selected for this study. Wheat (Triticum aestivum L.) was grown in the same field as the third crop without further application of amendments to evaluate the residual effects of the amendments on Cd uptake by wheat. Plants were harvested at maturity and grain, and straw yield along with Cd concentration in soil, straw, and grains was determined. The addition of MAP and gypsum significantly increased wheat growth and yield and decreased Cd accumulation in straw and grains compared to control while the reverse was found in S application. Both MAP and gypsum decreased AB-DTPA extractable Cd in soil while S increased the bioavailable Cd in soil. Both MAP and gypsum increased the Cd immobilization in the soil and S decreased Cd immobilization in a dose-additive manner. We conclude that MAP and gypsum had a significant residual effect on decreasing Cd uptake in wheat. The cost-benefit ratio revealed that gypsum is an effective amendment for decreasing Cd concentration in plants.

Warp sizing is an established method for improving the weaveability of textile yarns by coating orimpregnating warp yarns with a polymer that improves the efficiency of the weaving operation. Despiteits high cost, polyvinyl alcohol (PVA) normally shows better adhesion to fibers than other sizing agents likestarch which makes it an essential constituent of size liquor recipe. However PVA desized effluent is a majorchemical oxygen demand contributor to a textile plant’s primary oxygenation treatment of water operationand being biologically inert and presents a major threat to the environment. Therefore, the recovery andrecycling of PVA will not only be cost-effective but will also be eco-friendly. The aim of this research workis to recycle the warp size materials and to study the comparison of yarn mechanical properties sized withrecycled materials to the properties of yarn sized with conventional sizing. Ultrafiltration reverse osmosistechnology is used for the recovery and recycling of PVA size material. For this purpose, Ne 16/1 and Ne21/1 carded 100% cotton yarns were used and sized with both conventional sizing recipe and by 50%recycled PVA together with 50% fresh sizing recipe. It was found that yarn sized through recycled PVA sizingrecipe has almost the same (slightly lower) mechanical properties such as tensile strength, elongation andabrasion resistance as compared to yarn sized through conventional sizing recipe.

The objective of this study is to examine the effect of intumescent flame-retardants (IFR&rsquo, s) on the spinnability of sheath/core bicomponent melt-spun fibers, produced from Polylactic acid (PLA) single polymer composites, as IFR&rsquo, s have not been tested in bicomponent fibers so far. Highly crystalline PLA-containing IFR&rsquo, s was used in the core component, while an amorphous PLA was tested in the sheath component of melt-spun bicomponent fibers. Ammonium polyphosphate and lignin powder were used as acid, and carbon source, respectively, together with PES as a plasticizing agent in the core component of bicomponent fibers. Multifilament fibers, with sheath/core configurations, were produced on a pilot-scale melt spinning machine, and the changes in fibers mechanical properties and crystallinity were recorded in response to varying process parameters. The crystallinity of the bicomponent fibers was studied by differential scanning calorimetry and thermal stabilities were analyzed by thermogravimetric analysis. Thermally bonded, non-woven fabric samples, from as prepared bicomponent fibers, were produced and their fire properties, such as limiting oxygen index and cone calorimetry values were measured. However, the ignitability of fabric samples was tested by a single-flame source test. Cone calorimetry showed a 46% decline in the heat release rate of nonwovens, produced from FR PLA bicomponent fibers, compared to pure PLA nonwovens. This indicated the development of an intumescent char by leaving a residual mass of 34% relative to the initial mass of the sample. It was found that the IFRs can be melt spun into bicomponent fibers by sheath/core configuration, and the enhanced functionality in the fibers can be achieved with suitable mechanical properties.

Microalgae have an excellent potential for producing valuable natural products, including biofuels. Therefore, it is imperative to explore and document the existing microalgal flora and utilize their potentials to cope the increasing human needs. The present work aims at exploring and characterizing newly isolated microalgae from desert Cholistan, a habitat with myriad algal diversity. Light microscopy, scanning electron microscopy, and molecular phylogenetic approaches were used for species-level identification. Characterization and growth optimization of Scendesmus sp. were analyzed under three different growth modes to determine the most favorable conditions for increasing biomass, growth rate, and lipid content. The results revealed that mixotrophic (MT) mode significantly increases photosynthetic activity, growth rate, and lipid content with glycerol as supplement carbon source. The investigated Scenedesmus dimorphous produced a maximum dry weight of 1.73 g L-1 , improved fatty acid methyl esters profile and yield lipid up to 40% of DCW (68 g L-1 ) under MT mode, which is almost double to that of photoautotrophic cultivation. The glycerol availability in medium has been identified as the critical element for boosting growth and lipid content. Thus, it can reduce the cost of biofuel production.

The objective of this study is to assess the efficiency of biobased carbonization agent in intumescent formulations (IFRs) to examine the flame retardant properties of polylactic acid (PLA) composites and to investigate their melt-spinnability. We used phosphorous-based halogen free flame retardant (FR) and kraft lignin (KL) as bio-based carbonization agent. After melt compounding and molding into sheets by hot pressing various fire related characteristics of IFR composites were inspected and were characterized by different characterization methods. It was fascinating to discover that the introduction of 5&minus, 20 wt% FR increased the limiting oxygen index (LOI) of PLA composites from 20.1% to 23.2&minus, 33.5%. The addition of KL with content of 3&minus, 5 wt% further increased the LOI up to 36.6&minus, 37.8% and also endowed PLA/FR/KL composites with improved anti-dripping properties. Cone calorimetry revealed a 50% reduction in the peak heat release rate of the IFR composites in comparison to 100% PLA and confirmed the development of an intumescent char structure containing residue up to 40%. For comparative study, IFR composites containing pentaerythritol (PER) as a carbonization agent were also prepared and their FR properties were compared. IFR composites were melt spun and mechanical properties of multifilament yarns were tested. The analysis of char residues by energy dispersive X-ray spectrometry (EDS) and SEM images confirmed that PLA/FR/KL composites developed a thicker and more homogeneous char layer with better flame retardant properties confirming that the fire properties of PLA can be enhanced by using KL as a carbonization agent.

The Hindu-Kush Himalaya region extends over 4 million km2 across the eight countries. Knowingly, the Qinghai-Tibetan Plateau (QTP) is considered the principal altitudinal permafrost constituent on earth and is deemed as the third ‘pole’. Among which, the Zoige wetlands are located in the northeastern boundary of QTP, wrapping a total area of 6180 km2 with an average altitude of 3500 m. This entire region is the hotspot for methane emission since the last decade. Given the importance of methane emission, many studies have focused on the effect of environmental fluctuations on the overall methane profile and, more recently on the methanogenic community structure. The current review summarizes recent advancements of the methanogenic community and methane profile and outlines a framework for better understanding of the microbial ecology of the Zoige wetlands, China. Moreover, as microorganisms are indispensable to biogeochemical cycles, especially for methane, they are believed to be the best indicators to identify the condition of wetlands. Hence, we suggest that, underpinning the microbial profile could help understand the status of a wetland.

Production of microalgae as feedstock for biofuels must deal with a number of challenges including constraints imposed by local conditions. One solution is to use indigenous strains adapted to local climatic conditions. The present report describes the isolation, identification, and characterization of 32 microalgal strains from different ecological habitats: desert freshwater channels, northern region, and saline regions of Pakistan. The effects of temperature on algal growth rates, biomass productivity, and lipid content were determined through growth at 12, 20, and 35 &deg, C for 15 days under 2% CO2 Responses to temperature varied among species with 20 &deg, C being the optimum temperature in general, although, exceptionally, the best overall growth rate was found for strain S29 (0.311 d&minus, 1) at 12 &deg, C. In some cases high biomass productivity was observed at 35 &deg, C, and, depending upon the strain, the maximum lipid content was obtained at different temperatures, including 12 &deg, C. Fatty acid methyl ester (FAME) analysis showed that the major fatty acids present were palmitic, stearic, oleic, linoleic, and linolenic. Oleic acid (C18:1) was the predominant fatty acid, with the specific FAME profile varying with strain. Thus, there is a rich diversity of microalgal strains native to Pakistan, some of which, characterized here, could be suitable for biodiesel production or other biotechnological applications.

Starch, being a polyhydric compound with its natural charring ability, is an ideal candidate to serve as a carbonization agent in an intumescent system. This charring ability of starch, if accompanied by an acidic source, can generate an effective intumescent flame retardant (IFR) system, but the performance of starch-based composites in an IFR system has not been tested in detail. Here, we describe a PLA-based IFR system consisting of ammonium polyphosphate (APP) as acidic source and cornstarch as carbon source. We prepared different formulations by melt compounding followed by molding into sheets by hot pressing. The thermal behavior and surface morphology of the composites was investigated by thermogravimetric analysis and scanning electron microscopy respectively. We also conducted limiting oxygen index (LOI), UL-94, and cone calorimetry tests to characterize the flame-retardant properties. Cone calorimetry revealed a 66% reduction in the peak heat release rate of the IFR composites compared to pure PLA and indicated the development of an intumescent structure by leaving a residual mass of 43% relative to the initial mass of the sample. A mechanism of char formation has also been discussed in detail.

Rhizosphere drives plant uptake of sparingly soluble soil zinc (Zn). An investigation with three experiments was conducted to study organic acid exudation by two contrasting wheat genotypes (Sehar-06 and Vatan), Zn fractions in 10 different calcareous soils from Punjab, Pakistan, and release of different soil Zn fractions by organic acids. The two genotypes differed significantly in biomass production and Zn accumulation under deficient and optimum Zn levels in nutrient solution. At a deficient Zn level, Sehar-06 released more maleic acid in the rhizosphere than Vatan. Ten soils used in the present study had very different physicochemical properties; their total Zn and Zn distribution among different fractions varied significantly. Zinc release behaviour was determined by extracting the soils with 0.005 mol L−1 citric acid or maleic acid. The parabolic diffusion model best described Zn release as a function of time. Parabolic diffusion model fitting indicated more maleic acid-driven than citric acid-driven soil Zn mobility from different fractions. Cumulative Zn release in six consecutive extractions during 24 h ranged from 1.85 to 13.58 mg kg−1 using maleic acid and from 0.37 to 11.84 mg kg−1 using citric acid. In the selected calcareous soils, the results of stepwise linear regression indicated significant release of Fe-Mn oxide-bounded soil Zn by maleic acid and its availability to the Zn-efficient genotype. Hence, release of maleic acid by plants roots played an important role in phytoavailability of Zn from calcareous soils.

Adsorption and desorption reactions of zinc (Zn) in soils control its availability to plants. In the present investigation, time-dependent Zn release was evaluated using three organic acids [diethylenetriaminepentaacetic acid (DTPA), citric acid, and maleic acid] to depict the Zn fraction controlling Zn release rate from slightly calcareous to calcareous soils. Eight surface and two subsoil samples of selected soil series varied in their physicochemical properties, amount of Zn held in different chemical pools, and Zn-retention capacities (21–61%). Each soil was extracted for a total period of 24 h at 1:10 soil/extractant suspension ratio using 0.005 M DTPA. The time-dependent parabolic diffusion model best described the Zn release in six consecutive extractions. Soils differed in cumulative Zn extracted (1.09–3.81 mg kg−1 soil) and Zn release rate. Under similar conditions, three soils differing in Zn-retention capacities were also extracted with five different concentrations (0.01–0.0001 M) of citric an...

A hydroponics experiment was conducted to evaluate the role of potassium (K) and silicon (Si) in mitigating the deleterious effects of NaCl on sugarcane genotypes differing in salt tolerance. Two salt-sensitive (CPF 243 and SPF 213) and two salt-tolerant (HSF 240 and CP 77-400) sugarcane genotypes were grown for six weeks in ½ strength Johnson's nutrient solution. The nutrient solution was salinized by two NaCl levels (0 and 100 mmol L −1 NaCl) and supplied with two levels of K (0 and 3 mmol L −1 ) and Si (0 and 2 mmol L −1 ). Applied NaCl enhanced Na + concentration in plant tissues and significantly ( P ≤ 0.05) reduced shoot and root dry matter in four sugarcane genotypes. However, the magnitude of reduction was much greater in salt-sensitive genotypes than salt-tolerant genotypes. The salts interfered with the absorption of K + and Ca 2+ and significantly ( P ≤ 0.05) decreased their uptake in sugarcane genotypes. Addition of K and Si either alone or in combination significantly ( P ≤ 0.05) inhibited the uptake and transport of Na + from roots to shoots and improved dry matter yields under NaCl conditions. Potassium uptake, K + /Na + ratios, and Ca 2+ and Si uptake were also significantly ( P ≤ 0.05) increased by the addition of K and/or Si to the root medium. In this study, K and Si-enhanced salt tolerance in sugarcane genotypes was ascribed to decreased Na + concentration and increased K + with a resultant improvement in K + /Na + ratio, which is a good indicator to assess plant tolerance to salt stress. However, further verification of these results is warranted under field conditions.

Soil salinity is a major abiotic stress which adversely affects the yield and juice quality in sugarcane. However, the mineral nutrient status of plant plays a crucial role in increasing plant tolerance to salinity. We investigated the effects of K and/or Si on plant growth, yield and juice quality in two sugarcane genotypes differing in salinity tolerance. Addition of K and Si significantly (P ≤ 0.05) increased K and Si concentrations and decreased the accumulation of Na + in plants under salt stress. Cane yield and yield attributes were significantly (P ≤ 0.05) higher where K and Si were added. Juice quality characteristics like Brix (% soluble solids in juice), Pol (% sucrose in juice), commercial cane sugar (CCS) and sugar recovery in both sugarcane genotypes were also significantly (P ≤ 0.05) improved with the supplementation of K and Si. For most of the growth parameters, it was found that K either alone or in combination with Si was more effective to alleviate salt stress in both sugarcane genotypes than Si alone. Moreover, the beneficial effects of K and Si were more pronounced in salt sensitive genotype than in salt tolerant genotype. The results suggested that K and Si counteracted the deleterious effects of high salinity/sodicity in sugarcane by lowering the accumulation of Na + and increase in K + concentration with a resultant improvement in K + /Na + ratio which is a good indicator to assess plant tolerance to salinity.

Screening cultivars to grow under conditions of low phosphorus (P) availability and utilize P efficiently from compounds of low solubility in soils may be beneficial to overcome poor plant growth in P-deficient soils. The growth behavior and P utilization efficiency of seven wheat cultivars grown in hydroponics were studied, using rock phosphate as P source. The wheat cultivars grown for 30 days were significantly different in biomass accumulation, P uptake and P utilization efficiency. The dry matter production of all the cultivars was significantly correlated with P uptake, which in turn correlated to the drop in the root medium pH. The ranking of wheat cultivars on the basis of dry matter yield, P uptake and P utilization efficiency was Zamindar 80 > Yecora > C 271 > WL 711 > Barani 83 > PARI 73 > Rohtas. The cultivar Zamindar 80 appeared to possess the best growth potential in P-deficient soils.

Weeds are one of the most important factors that impose a great threat to the crop yield. In order to alleviate the weeds infestation in wheat ( Triticum aestivum L.), the efficacy of various pre and post-emergence herbicides were tested during Rabi 2009 to 2010 at the Agronomic Research Area, University of Agriculture, Faisalabad, Pakistan. Results promised that clodinafop propargyl at 0.045 kg a.i. ha -1 with maximum weed kill efficiency severely reduced the Avena fatua, Coronopus didymus and Melilotus indica population and dry weights compared with the control. Poor weed control was achieved using isoproturon at 1.5 kg a.i. ha -1 , isoproturon + diflufenicon at 0.98 kg a.i. ha -1 , fenoxaprop-p-ethyl at 1.00 kg a.i. ha -1 , tralkoxydim at 0.5 kg a.i. ha -1 and chlorsulfuron at 0.074 kg a.i. ha -1 . Considering total grain and straw yields (4900 kg ha -1 ); (6600 kg ha -1 ), post-emergence clodinafop propargyl at 0.045 kg a.i. ha -1 causes an excellent increase in wheat yield (51.02%) over control. The highest spikebearing tillers (380.67), number of grains spike -1 (47.28) and 1000-grain weight (49.38 g) were maximum in clodinafop propargyl at 0.045 kg a.i. ha -1 as post-emergence treated plots. Based on the total wheat yield (grain and straw) obtained, isoproturon at 1.5 kg a.i. ha -1 , metribuzin + fenoxaprop-p-ethyl at 1.00 + 1.00 kg a.i. ha -1 , chlorsulfuron at 0.074 kg a.i. ha -1 seemed someway phytotoxic to crop plants and depressed wheat yield. Hence, maximum net income of Rs. 136997 ha -1 and maximum MRR (%) of 231316.6 was recorded with the use of clodinafop propargyl at 0.045 kg a.i. ha -1 as post applied followed by carfentrazone ethyl (0.015 kg a.i ha -1 ) with the MRR (%) of 89700. Key words: Triticum aestivum L., Avena fatua, Coronopus didymus, Melilotus indica, clodinafop propargyl, weed control, herbicides.