Effects of Plastic Mulching and Basal Nitrogen Application Depth on Nitrogen Use Efficiency and Yield in Maize

The demand for increased grain production to support population and consumption growth has led to increased interest in field management approaches that incorporate plastic mulching and fertilization management. The purpose of this study was to investigate the effects of plastic mulching and basal nitrogen (N)-fertilizer application depth on N balance estimations, N use efficiency (NUE) and maize yield. The experiment was conducted in 2014 and 2015 with six treatments: no N fertilizer and no mulching (CK), traditional broadcast N fertilizer with mulching (T0), basal N-fertilizer application at a depth of 6 cm with no mulching (T1), basal N-fertilizer application at a depth of 6 cm with plastic mulching (T2), basal N-fertilizer application at a depth of 12 cm with no mulching (T3) and basal N-fertilizer application at a depth of 12 cm with plastic mulching (T4). Mulching and basal N-fertilizer application depth each had significant effects on grain yield, but there were no significant interactions between them. The highest grain yield was observed in the T2 treatment and was 89.1% and 99.8% higher than the grain yield in the CK treatment in 2014 and 2015, respectively. The N uptake in T2 was 21.3% and 25.3% higher than that in the T0 treatment in 2014 and 2015, respectively. Relative to the value in the T0 treatment, the mean N loss over the 2 years was reduced by 34.6% in T2 and by 39.8% in T4. The basal N-fertilizer application depth of 12 cm yielded an obvious increase in NUE, but a high N residual remained below 50 cm after harvest, indicating the higher potential for N losses. In addition, the field application of this type of fertilizer management would require more labor in the absence of the implementation of mechanization. Based on the results, basal N-fertilizer application a depth of 6 cm without plastic mulching is recommended because it significantly increased grain yield and NUE, reduced N loss and requires no investment in plastic film, which are conducive to food security and environmental conservation

Effects on photosynthetic response and biomass productivity of acacia longifolia ssp. longifolia under elevated CO2 and water-limited regimes

It is known that the impact of elevated CO2 (eCO2) will cause differential photosynthetic responses in plants, resulting in varying magnitudes of growth and productivity of competing species. Because of the aggressive invasive nature of Acacia longifolia ssp. longifolia, this study is designed to investigate the effect of eCO2 on gas exchange parameters, water use efficiency, photosystem II (PSII) activities, and growth of this species. Plants of A. longifolia ssp. longifolia were grown at 400 ppm (ambient) and 700 ppm (elevated) CO2 under 100 and 60% field capacity. Leaf gas exchange parameters, water use efficiency, intrinsic water use efficiency, instantaneous carboxylation efficiency, and PSII activity were measured for 10 days at 2-day intervals. eCO2 mitigated the adverse effects of drought conditions on the aforementioned parameters compared to that grown under ambient CO2 (aCO2) conditions. A. longifolia, grown under drought conditions and re-watered at day 8, indicated a partial recovery in most of the parameters measured, suggesting that the recovery of this species under eCO2 will be higher than that with aCO2 concentration. This gave an increase in water use efficiency, which is one of the reasons for the observed enhanced growth of A. longifolia under drought stress. Thus, eCO2 will allow to adopt this species in the new environment, even under severe climatic conditions, and foreshadow its likelihood of invasion into new areas. Copyright © 2022 Javaid, Wang, Florentine, Ashraf, Mahmood, Li and Fiaz

Temperature Extremes in Cotton Production and Mitigation Strategies

Cotton is an important cash crop, providing raw material for different industries and plays crucial role in the economy of several countries. It requires optimum temperature for economic production and causes reduced yield otherwise. Extreme temperature, more importantly, high temperature causes serious yield reduction in cotton by affecting its physiology, biochemistry and quality leading to poor agronomic produce. Freezing temperature also affect the germination percentage and seedling establishment. Several breeding and genomics based studies were conducted to improve the cotton production under high and low temperature stress in cotton. Here we overviewed several agronomic practices to mitigate the effect of extreme temperature, and multiple breeding and molecular approaches to enhance the genetic potential of cotton for temperature tolerance by Marker assisted selection or transgenic approach

Zinc fortification and alleviation of cadmium stress by application of lysine chelated zinc on different varieties of wheat and rice in cadmium stressed soil

Sustainable and cost-effective methods are required to increase the food production and decrease the toxic effects of heavy metals. Most of the agriculture land is contaminated with cadmium (Cd). The present study was designed to minimize the toxic effect of Cd stress (0, 10 and 20 mg kg1-) on tolerant and sensitive varieties of wheat (Punjab-2011; Sammar) and rice (Kisan Basmati; Chenab) under Zn-lysine (Zn-lys) application as foliar spray (0, 12.5 and 25 mM) and seed priming (0, 3 and 6 ppm). Remarkable decrease was observed in plant growth, physiology and biochemistry as well as increase in Cd uptake, roots to shoots and grains of both crops. Cd significantly reduced the root and shoot lengths, root and shoot dry weights, transpiration rate, photosynthetic rate, stomatal conductance and water use efficiency as well as chlorophyll contents associated with enhanced electrolyte leakage (EL), malondialdehyde (MDA) and H2O2 and Cd uptake in different plant parts including grains of both crop varieties. The foliar application of Zn-lys (0, 12.5 and 25 mM) ameliorated the toxic effect of Cd on growth and physiology associated with decrease in EL, MDA and H2O2 and improved the activities of SOD, POD, CAT and APX enzymes with decreasing Cd uptake in tolerant varieties of wheat and rice as compared to seed priming. Furthermore, it has been investigated that the foliar application of Zn-lys is effective to improve quality of wheat and rice tolerant varieties (Punjab-2011 and Chenab) under Cd contamination soils

Microbe-citric acid assisted phytoremediation of chromium by castor bean (Ricinus communis L.)

Chromium is one of the highly toxic heavy metals to plant growth and development especially hexavalent chromium (Cr+6) due to its readily available nature and mobility into the environment. The chelating agents and hyperaccumulator plant can contribute to remediating the heavy metals from the contaminated medium. This study was conducted to analyze the role of citric acid and chromium resistant bacteria in castor bean to remediate Cr+6 from the polluted soil. The soil was spiked with different levels of citric acid (0, 2.5, 5 mM) and chromium (0, 10, 20 mg kg−1). The ripened plants were harvested and analyzed for growth parameters, chlorophyll contents, gas exchange parameters, oxidative stress markers, antioxidant enzymes activities and chromium accumulation in different parts of plants. The high concentration of chromium 20 mg kg−1 drastically reduced the plant growth, decreased photosynthetic rate and increased oxidative stress. The application of CA improved the plant growth even at the highest concentration of chromium which was further boosted by the combined application of CA and chromium resistant bacteria. However, the performance of staphylococcus aureus was found significantly better than Bacillus subtilis due to its better ability to tolerate chromium toxicity even at high concentrations. The findings proved that castor bean has excellent potential to tolerate high chromium concentrations and can be effectively used to remediate metals contaminated soil. Further, CA and metal resistant bacteria can significantly enhance the phytoremediation potential of castor bean and other hyperaccumulator plants. The bacteria assisted phytoremediation coupled with the chelating agent can be a practical approach to remediate the metals contaminating soils

Floating Treatment Wetlands (FTWs) is an Innovative Approach for the Remediation of Petroleum Hydrocarbons-Contaminated Water

Globally, water resources contaminated with petroleum hydrocarbons are under much consideration due to their hazardous effects on human beings as well as on plants and animals in the ecosystem. Petroleum hydrocarbons are classified as recalcitrant pollutants in nature. These petroleum products are mostly released in the water resources during the petroleum refining process by oil refineries. The conventional clean-up technologies for hydrocarbons contaminated water have more destructive effects on the aquatic and land ecosystems. Consequently, to develop cost-effective and more environment-friendly techniques that clean up the environment and restore the marine ecosystem to its original forms. Keeping in view, this review article explores the detailed information on fabrication, cost-effectiveness, and an overview of innovation of the floating treatment wetlands (FTWs) using plants and bacterial combined functions to remediate the petroleum hydrocarbons contaminated water. The review also discusses the improvement of microbial efficacy for hydrocarbon degradation using FTWs. The review article shows the various applications of FTWs to remove different organic pollutants in petroleum hydrocarbons contaminated water. The review also describes the prospective benefits of FTWs for their multiple uses for removal of hydrocarbons, chemical oxygen demand (COD), biochemical oxygen demand (BOD), phenol, and solids from hydrocarbons contaminated water. This review widely discusses the role of hydrocarbons in degrading bacteria, and wetland plants and the mechanism involved during the remediation process of hydrocarbons in FTWs. It further demonstrates features disturbing the treatment efficiency of FTWs, and finally, it is concluded by successful applications of FTWs and various suggestions for potential future research prospects. Graphical Abstract: [Figure not available: see fulltext.

Individual and Synergic Effects of Phosphorus and Gibberellic Acid on Organic Acids Exudation Pattern, Ultra-Structure of Chloroplast and Stress Response Gene Expression in Cu-Stressed Jute (Corchorus Capsularis L.)

Copper (Cu) pollution in agricultural soils is considered as a serious health risk due to its accumulation in plants. Thus, there is an urgent need to optimize nutrient application for higher yield with lower Cu uptake to ensure food security. A pot experiment was conducted to determine the effects of single and/or combined application of different levels (0 and 80 kg ha−1) of phosphorus (P) and gibberellic acid (0 and 100 mg L−1) on Cu accumulation, morpho-physiological and antioxidative defence attributes of jute (Corchorus capsularis L.) exposed to severe Cu stress (0, 200 and 400 mg kg−1). Results revealed that C. capsularis tolerated up to 200 mg kg−1 Cu concentration without a significant (

Kappa-carrageenan as an effective cryoprotectant on water mobility and functional properties of grass carp myofibrillar protein gel during frozen storage

The effect of kappa-carrageenan oligosaccharides was analyzed on the gelling abilities of grass carp myofibrillar proteins (MP) during 60 days frozen storage. Four gel treatments were prepared: control without additives (C), a positive control with sucrose: sorbitol (PC), and two batches with 1 and 2% of kappa-carrageenan (KC). All MP gels showed a significant decline in the functional and structural properties. Water holding capacity (WHC) and textural properties of control MP gel was significantly reduced due to oxidative changes, whereas weak cross-linking between amino acid molecules and denaturation of myosin observed. In contrast, PC and KC showed a significant control on the reduction of functional properties due to the enhanced inter/intra-molecular interactions and less formation of ice crystals. Addition of KC (2%) significantly restricted the decline in WHC from 95.45 to 75.47%, which is well associated with high hydrogen proton density. Besides that, low field nuclear magnetic resonance (LF-NMR) analysis exhibited a restricted increase in T22 relaxation time in samples added with KC (2%). Overall, MP gel with KC (2%) proved to be an effective alternative in comparison with PC and could be efficient in the production and commercialization of fish and other seafood products.National Natural Science Foundation of China | Ref. 31972104National Natural Science Foundation of China | Ref. 51809224National Natural Science Foundation of China | Ref. 3147169

The impact of aqueous and N-hexane extracts of three Fabaceae species on seed germination and seedling growth of some broadleaved weed species

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

S‐Fertilizer (Elemental Sulfur) Improves the Phytoextraction of Cadmium through Solanum nigrum L.

Soil contamination with toxic heavy metals [such as cadmium (Cd)] is becoming a serious global problem due to the rapid development of the social economy. This study was carried out to assess the beneficial role of two different kinds of (S)‐fertilizer in the phytoremediation of Cd contaminated soil through Solanum nigrum L. Gypsum (Gyp) and Elemental sulfur (ES) was applied alone and in combination with different ratios (0, 100:0, 0:100, 50:50 mg kg−1) accompanied by different Cd levels (0, 25, 50 mg kg−1). After seventy days of sowing, plants were harvested for determination of growth, physiological characteristics, oxidants and antioxidants, along with Cd uptake from different parts of the plant. Cd toxicity significantly inhibited growth, physiology and plant defence systems, and also increased Cd uptake in the roots and shoots of Solanum nigrum L. The application of Gyp 100 mg kg−1 boosted plant growth and physiology along with oxidants and antioxidants activity as compared to ES 100 mg kg−1 alone, and combine application of GYP+ES 50 + 50 mg kg−1. The application of ES 100 mg kg−1 showed an effective approach to decreasing Cd uptake as compared to Gyp 100 mg kg−1. Overall results showed that the combined application of GYP+ES 50 + 50 mg kg−1 significantly enhanced the phytoremediation potential of S. nigrum in Cd contaminated soil. Thus, it is highly recommended to apply the combined application of GYP+ES for phytoremediation of Cd contaminated soil