Continuously increasing energy demand and growing concern about energy resources has attracted much research in the field of clean and sustainable energy sources. In this context, zero-emission fuels are required for energy production to reduce the usage of fossil fuel resources. Here, we present the synthesis of Pd-Ag-decorated reduced graphene oxide (rGO) nanostructures using a green chemical approach with stevia extract for hydrogen production and antibacterial studies under light irradiation. Moreover, bimetallic nanostructures are potentially lime lighted due to their synergetic effect in both scientific and technical aspects. Structural characteristics such as crystal structure and morphological features of the synthesized nanostructures were analyzed using X-ray diffraction and transmission electron microscopy. Analysis of elemental composition and oxidation states was carried out by X-ray photoelectron spectroscopy. Optical characteristics of the biosynthesized nanostructures were obtained by UV-Vis absorption spectroscopy, and Fourier transform infrared spectroscopy was used to investigate possible functional groups that act as reducing and capping agents. The antimicrobial activity of the biosynthesized Pd-Ag-decorated rGO nanostructures was excellent, inactivating 96% of Escherichia coli cells during experiments over 150 min under visible light irradiation. Hence, these biosynthesized Pd-Ag-decorated rGO nanostructures can be utilized for alternative nanomaterial-based drug development in the future.
Awareness of environmental concerns influences researchers to develop an alternative method of developing natural fiber composite materials, to reduce the consumption of synthetic fibers. This research attempted testing the neem (Azadirachta indica) fiber and the banyan (Ficus benghalensis) fiber at different weight fractions, under flame retardant and thermal testing, in the interest of manufacturing efficient products and parts in real-time applications. The hybrid composite consists of 25% fiber reinforcement, 70% matrix material, and 5% bran filler. Their thermal properties-short-term heat deflection, temperature, thermal conductivity, and thermal expansion-were used to quantify the effect of potential epoxy composites. Although natural composite materials are widely utilized, their uses are limited since many of them are combustible. As a result, there has been a lot of focus on making them flame resistant. The thermal analysis revealed the sample B was given 26% more short-term heat resistance when the presence of banyan fiber loading is maximum. The maximum heat deflection temperature occurred in sample A (104.5 °C) and sample B (99.2 °C), which shows a 36% greater thermal expansion compared with chopped neem fiber loading. In sample F, an increased chopped neem fiber weight fraction gave a 40% higher thermal conductivity, when compared to increasing the bidirectional banyan mat of this hybrid composite. The maximum flame retardant capacity occurred in samples A and B, with endurance up to 12.9 and 11.8 min during the flame test of the hybrid composites.
Sunflower production is significantly lower in arid and semi-arid regions due to various crop management problem. Conservation of tillage provides the most excellent opportunity to reduce degradation of soil reserves and increase soil productivity. The main objective of this study was to investigate the combined effects of conservation tillage and drought stress on growth and productivity of different sunflower hybrids. Experimental treatments included two sunflower hybrids ('NK-Senji' and 'S-278'), two drought stress treatments (i.e., well-watered and drought stress at flowering and grain filling stages) and three tillage practices (i.e., conservation, minimum and deep tillage). The results indicated that morphological and physiological parameters, and yield-related traits were significantly (P≤0.05) affected by all individual factors; however, their interactive effects were non-significant. Among sunflower hybrids, 'NK-Senji' performed better for morphological, physiological, and yield-related traits than 'S-278'. Similarly, conservation tillage observed better traits compared to the rest of the tillage practices included in the study. Nonetheless, conservation tillage improved growth and yield-related traits of hybrid 'NK-Senji' under drought stress. Hence, it is concluded that conservation tillage can improve the productivity of sunflower under low moisture availability. Therefore, conservation tillage could be suggested in the areas of lower water ability to improve sunflower production. Nonetheless, sunflower hybrids or varieties need thorough testing for their adaptability to conservation tillage and low moisture availability before making recommendations.
Weed infestation is a persistent problem for centuries and continues to be major yield reducing issue in modern agriculture. Chemical weed control through herbicides results in numerous ecological, environmental, and health-related issues. Moreover, numerous herbicides have evolved resistance against available herbicides. Plant extracts are regarded as an alternative to herbicides and a good weed management option. The use of plant extracts is environmentally safe and could solve the problem of herbicide resistance. Therefore, laboratory and wire house experiments were conducted to evaluate the phytotoxic potential of three Fabaceae species, i.e., Cassia occidentalis L. (Coffee senna), Sesbania sesban (L.) Merr. (Common sesban) and Melilotus alba Medik. (White sweetclover) against seed germination and seedling growth of some broadleaved weed species. Firstly, N-hexane and aqueous extracts of these species were assessed for their phytotoxic effect against lettuce (Lactuca sativa L.). The extracts found more potent were further tested against germination and seedling growth of four broadleaved weed species, i.e., Parthenium hysterophorus L. (Santa-Maria), Trianthema portulacastrum L. (Pigweed), Melilotus indica L (Indian sweetclover). and Rumex dentatus L. (Toothed dock) in Petri dish and pot experiments. Aqueous extracts of all species were more toxic than their N-hexane forms for seed germination and seedling growth of lettuce; therefore, aqueous extracts were assessed for their phytotoxic potential against four broadleaved weed species. Aqueous extracts of all species proved phytotoxic against T. portulacastrum, P. hysterophorus, M. indica and R. dentatus and retarder their germination by 57, 90, 100 and 58%, respectively. Nevertheless, foliar spray of C. occidentalis extract was the most effective against T. portulacastrum as it reduced its dry biomass by 72%, while M. alba was effective against P. hysterophorus, R. dentatus and M. indica and reduced their dry biomass by 55, 68 and 81%, respectively. It is concluded that aqueous extracts of M. alba, S. sesban and C. occidentalis could be used to retard seed germination of T. portulacastrum, P. hysterophorus, M. indica and R. dentatus. Similarly, aqueous extracts of C. occidentalis can be used to suppress dry biomass of T. portulacastrum, and those of M. alba against P. hysterophorus, R. dentatus. However, use of these extracts needs their thorough testing under field conditions.
Wheat (Triticum aestivum L.) production is significantly altered by the infestation of sucking insects, particularly aphids. Chemical sprays are not recommended for the management of aphids as wheat grains are consumed soon after crop harvests. Therefore, determining the susceptibility of different wheat genotypes and selecting the most tolerant genotype could significantly lower aphid infestation. This study evaluated the susceptibility of six different wheat genotypes ('Sehar-2006', 'Shafaq-2006', 'Faisalabad-2008', 'Lasani-2008', 'Millat-2011' and 'Punjab-2011') to three aphid species (Rhopalosiphum padi Linnaeus, Schizaphis graminum Rondani, Sitobion avenae Fabricius) at various growth stages. Seed dressing with insecticides and plant extracts were also evaluated for their efficacy to reduce the incidence of these aphid species. Afterwards, an economic analysis was performed to compute cost-benefit ratio and assess the economic feasibility for the use of insecticides and plant extracts. Aphids' infestation was recorded from the seedling stage and their population gradually increased as growth progressed towards tillering, stem elongation, heading, dough and ripening stages. The most susceptible growth stage was heading with 21.89 aphids/tiller followed by stem elongation (14.89 aphids/tiller) and dough stage (13.56 aphids/tiller). The genotype 'Punjab-2011' recorded the lower aphid infestation than 'Faisalabad-2008', 'Sehar-2006', 'Lasani-2008' and 'Shafaq-2006'. Rhopalosiphum padi appeared during mid-February, whereas S. graminum and S. avenae appeared during first week of March. Significant differences were recorded for losses in number of grains/spike and 1000-grain weight among tested wheat genotypes. The aphid population had non-significant correlation with yield-related traits. Hicap proved the most effective for the management of aphid species followed by Hombre and Husk among tested seed dressers, while Citrullus colocynthis L. and Moringa oleifera Lam. plant extracts exhibited the highest efficacy among different plant extracts used in the study. Economic analysis depicted that use of Hombre and Hicap resulted in the highest income and benefit cost ratio. Therefore, use of genotype Punjab-2011' and seed dressing with Hombre and Hicap can be successfully used to lower aphid infestation and get higher economic returns for wheat crop.
Helicoverpa armigera (Hub.) is a destructive pest of the tomato (Lycopersicon esculentum Mill) crop in Pakistan. Although insecticides are the primary management strategy used to control H. armigera, most of them are not effective due to considerable toxic residual effects on the fruits. Nonetheless, H. armigera is rapidly evolving resistance against the available pesticides for its management. This situation calls upon the need of alternative management options against the pest. Different plant extracts have been suggested as a viable, environment-friendly option for plant protection with minimal side effects. Furthermore, the plant extracts could also manage the insect species evolving resistance against pesticides. This study evaluated the efficacy of different plant extracts (i.e., Neem seed, turmeric, garlic and marsh pepper) against H. armigera. Furthermore, the impact of the plant extracts on growth and yield of tomato crop was also tested under field conditions. The results revealed that all plant extracts resulted in higher mortality of H. armigera compared to control. Similarly, the highest plant height was observed for the plants treated with the plant extracts compared to untreated plants. Moreover, the highest tomato yield was observed in plants treated with plant extracts, especially with neem seed (21.013 kg/plot) followed by pepper extract (19.25 kg/plot), and garlic extract 18.4 kg/plot) compared to the untreated plants (8.9 kg/plot). It is concluded that plant extracts can be used as eco-friendly approaches for improving tomato yield and resistance management of H. armigera.
Organic residues are an important factor that directly affects fruiting tree seedlings' health at earlier stages. It provides a suitable environment for seedling growth by providing better nutrient ions, water, and aeration. However, low organic contents and high shrinkage of most organic materials mostly deteriorate ideal potting media characteristics. Low aeration, high water, and nutrients leaching decrease seedling growth and cause a significant loss of valuable resources. That is why the current study was conducted to screen out the best indigenous materials based on particle size to produce good characteristics bearing potting media. For that, eight different ingredients, i.e., "sugarcane", "coconut coir", "wheat straw", "rice straw", "corn cob", "leaf litter", "farmyard manure", and "sunflower heads" were collected. Initially, all the materials were air-dried and processes as per requirement. After grinding, three particles size (fine = < 2 mm, medium = 3 mm and coarse = 5 mm) were separated by sieving. Results showed that decreasing particle size in "rice straw", "corn cob", "farmyard manure," and "sunflower head" decreased leachate pH. Higher EC in leachates was negatively correlated with particle size in all potting media ingredients. Except for farmyard manure, fine particle size increases the water-holding ability of potting media ingredients. However, air-filled porosity was associated with a decrease in particle size of potting media in gradients. In conclusion, farmyard manure, "sunflower heads", "leaf litter" and "sugarcane" should be incorporated while making a combination for potting media. More investigations are suggested by mixing different particle size ingredients to prepare potting media.