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Traditional fertilization not only enhances the acidification of soil but also leads toward eutrophication. Here stimulatory and inhibitory effects of foliar fertilization of Cordia based silver nanoparticles (AgNPs) were studied on lettuce (Lactuca sativa L.) biomass accumulation, antioxidant activity, and morphological and anatomical modifications. The AgNPs were foliar supplied with a concentration of 25, 50, and 100 ppm along with control (deionized water) and negative control AgNO3 for consecutive 25 days. The L. sativa fresh and dry biomass accumulation were significantly higher by 53%, leaf area by 25%, and leaf water holding capacity by 207% for foliar sprayed at 25 ppm concentration of AgNPs. The application of AgNPs and AgNO3 had significantly shortened the shoot length (52%), while foliar spray of AgNPs promoted the root length (40%). Among different concentrations of AgNPs, the 50 ppm improved the thickness of stem epidermis (44%), hypodermis (130%), and cortex cell area (372%). For antioxidant studies, the 25 ppm of AgNPs depicted the highest anti-oxidative activity for 2,2-diphenyl-1-picryl hydrazyl radical scavenging activity (75%), total antioxidant capacity (167%), total phenolic content (292%), and total reducing power (60%), while 50 ppm showed the maximum activity for total flavonoid content (243%) as compared to control. Thus, we may conclude that the AgNPs have both stimulatory and inhibitory effects on L. sativa. These effects were dependent on the concentration of the nanoparticles and have varied for different growth, antioxidants, and anatomical traits of the plant.

The synthesis methodology, particle size and shape, dose optimization, and toxicity studies of nano-fertilizers are vital prior to their field application. This study investigates the comparative response of chemically synthesized and biologically synthesized iron oxide nanorods (NRs) using moringa olefera along with bulk FeCl3 on summer maize (Zea mays). It is found that FeCl3 salt and chemically synthesized iron oxides NRs caused growth retardation and impaired plant physiological and anti-oxidative activities at a concentration higher than 25 mg/L due to toxicity by over accumulation. While iron released form biologically synthesized NRs have shown significantly positive results even at 50 mg/L due to their low toxicity, an improved leaf area (13%), number of leaves per plant (26%), total chlorophyll content (80%) and nitrate content (6%) with biologically synthesized NRs are obtained. Moreover, the plant anti-oxidative activity also increased on treatment with biologically synthesized NRs because of their ability to form a complex with metal ions. These findings suggest that biologically synthesized iron oxides NRs are an efficient iron source and can last for a long time. Thus, proving that nanofertilizer are required to have specific surface chemistry to release the nutrient in an appropriate concentration for better plant growth., Nanofertilizers; Withania coagulans; Iron nutrition; Bioinspired synthesis; Anti-oxidative stress, Agricultural science; Agronomy; Chemical engineering; Environmental hazard; Environmental science; Environmental toxicology; Materials science

A laboratory incubation experiment was executed to examine the role of phosphate solubilizing bacteria (with PSB and without PSB) and poultry manure (4, 8 and 12 t PM ha(−1)) in improving P mobilization/mineralization under four different lime regimes (4.78, 10, 15 and 20% CaCO(3) M/M) for 56 days using three factorial complete randomized design (CRD) with triplicates. Phosphorus availability progressively increased over time irrespective of PSB inoculation, PM and lime levels. The PSB and PM (4–12 t ha(−1)) addition into soil significantly increased Olsen P at all incubation intervals. Post incubation PSB survival increased by 12 and 9% with inoculation and 12 t PM ha(−1) over control and 4 t PM ha(−1), respectively. Liming ominously reduced P mobilization/mineralization by 1.3, 2.6 and 10.5% and PSB population by 6.6, 7.3 and 16.3% at 10, 15 and 20% (lime), respectively, over control at day 56. However, PSB and PM addition (with increasing rate) into soil significantly counterbalanced these ill effects of lime. Thus, the application of PSB and PM is a promising measure to enhance P availability in calcareous soils and shall be practiced.

Soil contamination with heavy metals has become a global environmental-health concern. A series of greenhouse experiments were conducted to investigate the effects of rice straw, rice straw derived biochar (BC), multi-walled carbon nanotubes, and single superphosphate (SSP) on immobilization of Pb and Cu via sequential extraction of BCR, total characteristics leaching procedure (TCLP), and metals phytoavailability to rapeseed in Pb and Cu spiked soil. Moreover, the residual effect of applied soil amendments on growth and uptake of Pb and Cu in tomato was also investigated in the metals spiked soil. In results, the addition of BC to Pb and Cu spiked soil proved the most effective amendment in modifying the distribution pattern of Pb and Cu from acid-soluble (less bioavailable) to residual fraction (non-toxic), thereby improving the geochemical stability of contaminated soil. The application of BC (6% w/w) reduced the uptake of Pb and Cu in shoot and root by 46 and 36%, and 77 and 58%, respectively. While investigating the residual impact in tomato, the uptake was decreased by 36 and 66% for Pb and 29 and 61% for Cu in shoot and root samples, respectively. With the application of BC (6% w/w), the concentrations of Pb and Cu in the shoot portion of tomato were below the permissible limits as set by the world health organization. The application of SSP was more effective in reducing TCLP-Pb to 0.2 mg L−1 in metals spiked soil compared to the other amendments. However, the bioavailability of Cu was increased with increasing SSP addition. In conclusion, the application of BC was more effective in reducing Pb and Cu phytoavailability through immobilization in contaminated soil compared to the other organic and inorganic amendments.

A two-year experiment was conducted to ascertain the effects of exogenously applied plant growth regulators (PGR) on rice growth and yield attributes under high day (HDT) and high night temperature (HNT). Two rice cultivars (IR-64 and Huanghuazhan) were subjected to temperature treatments in controlled growth chambers and four different combinations of ascorbic acid (Vc), alpha-tocopherol (Ve), brassinosteroids (Br), methyl jasmonates (MeJA) and triazoles (Tr) were applied. High temperature severely affected rice morphology, and also reduced leaf area, above- and below-ground biomass, photosynthesis, and water use efficiency, while increased the leaf water potential of both rice cultivars. Grain yield and its related attributes except number of panicles, were reduced under high temperature. The HDT posed more negative effects on rice physiological attributes, while HNT was more detrimental for grain formation and yield. The Huanghuazhan performed better than IR-64 under high temperature stress with better growth and higher grain yield. Exogenous application of PGRs was helpful in alleviating the adverse effects of high temperature. Among PGR combinations, the Vc+Ve+MejA+Br was the most effective treatment for both cultivars under high temperature stress. The highest grain production by Vc+Ve+MejA+Br treated plants was due to enhanced photosynthesis, spikelet fertility and grain filling, which compensated the adversities of high temperature stress. Taken together, these results will be of worth for further understanding the adaptation and survival mechanisms of rice to high temperature and will assist in developing heat-resistant rice germplasm in future.

Rahman, Muhammad Habib ur/0000-0002-2823-9959; Jabran, Khawar/0000-0001-8512-3330; Hakeem, Khalid Rehman/0000-0001-7824-4695; Amin, Asad/0000-0003-2242-8377; Ata-Ul-Karim, Syed Tahir/0000-0001-5233-4502; Jatoi, Ghulam Hussain/0000-0002-7266-1567; Rehmani, M.I.A./0000-0001-7922-1233; Bajwa, Ali/0000-0002-7171-3118; Nadeem, Muhammad/0000-0002-7426-1196; Ata-Ul-Karim, Syed Tahir/0000-0001-5233-4502; Ameen, Asif/0000-0002-3982-7000; Islam, Faisal/0000-0002-1471-1570 WOS: 000397013000067 PubMed: 28054268 Crop nutrient management is an essential component of any cropping system. With increasing concerns over environmental protection, improvement in fertilizer use efficiencies has become a prime goal in global agriculture system. Phosphorus (P) is one of the most important nutrients, and strategies are required to optimize its use in important arable crops like cotton (Gossypium hirsutum L.) that has great significance. Sustainable P use in crop production could significantly avoid environmental hazards resulting from over-P fertilization. Crop growth modeling has emerged as an effective tool to assess and predict the optimal nutrient requirements for different crops. In present study, Decision Support System for Agro-technology Transfer (DSSAT) sub-model CSM-CROPGRO- Cotton-P was evaluated to estimate the observed and simulated P use in two cotton cultivars grown at three P application rates under the semi-arid climate of southern Punjab, Pakistan. The results revealed that both the cultivars performed best at medium rate of P application (57 kg ha(-1)) in terms of days to anthesis, days to maturity, seed cotton yield, total dry matter production, and harvest index during 2013 and 2014. Cultivar FH-142 performed better than MNH-886 in terms of different yield components. There was a good agreement between observed and simulated days to anthesis (0 to 1 day), days to maturity (0 to 2 days), seed cotton yield, total dry matter, and harvest index with an error of -4.4 to 15%, 12-7.5%, and 13-9.5% in MNH-886 and for FH-142, 4-16%, 19-11%, and 16-8.3% for growing years 2013 and 2014, respectively. CROPGRO-Cotton-P would be a useful tool to forecast cotton yield under different levels of P in cotton production system of the semi-arid climate of Southern Punjab. Government of Australia [4915_2015]; Higher Education Commission (HEC) of PakistanHigher Education Commission of Pakistan The first author is grateful to the International Global Change Institute (IGCI) Hamilton, New Zealand, for providing the software (SimCLIM2013) and the required climatic dataset for future projections with for southern Punjab, Pakistan. The first author is thankful to Prof. Dr. Gerrit Hoogenboom (Ex-Director, AgWeatherNet, Washington State University, USA; Currently: University of Florida-USA), for his technical guidance and support during the entire period of study and modeling work. Furthermore, first author is highly thankful from NASA for weather data of respective years (which was obtained from website http://power.larc.nasa.gov/cgi-bin/cgiwrap). The corresponding author (Wajid NASIM) is highly thankful to Government of Australia, for Endeavor Research Award/Fellowship (No. 4915_2015) to The Commonwealth Scientific and Industrial Research Organization (CSIRO), Sustainable Agriculture, National Research Flagship, Toowoomba-QLD 4350, Australia. Furthermore, co-authors (Wajid NASIM and Shakeel AHMAD) are highly thankful for Higher Education Commission (HEC) of Pakistan for partial funding.

Screening of drought tolerant genotypes for arid land cultivation is the best approach to avoid yield losses as breeding and selection are time taking techniques. Current experiment was planned to evaluate late sown wheat cultivars potential for drought tolerance and adaptability in Jeddah region, KSA. Four wheat cultivars (Yocoro, Rojo, Faisalabad-2008, F-10 and L-7096) were tested against drought stress applied as (75% and 50%) of total crop water requirement. A 100% water requirement was also applied as control. Data regarding crop growth stages, growth, grain yield and yield contributors were tested by using MSTAT-C. Drought stress significantly decreased all growth and yield traits except harvest index and the effect of water stress was the most severe where 50% of the total water requirement was applied. Both studied crop growth stages (days to complete tillering and days to complete 50% heading) were also affected to applied water stress and effect was more pronounced for days to complete 50% heading. Studied cultivars responded variably for different growth and yield traits. Cultivar Yoco Rojo took minimum days to complete tillering and heading while L-7096 presented the highest plant height and dry biomass accumulation. Faisalabad-2008 reported maximum values for grain yield and yield contributors except spike length that was maximum in Yocoro Rojo. Based on the field evaluation, it’s concluded that Faisalabad-2008 produced significant results for growth and yield traits among studied cultivars and can be successfully grown in arid land conditions under limited water supplies.Â