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Among biotic and abiotic stresses, the most restrictive for plant distribution is salt stress, where different concentrations might exert harmful effects on seed germination. Recently, nanomaterials were used successfully to mitigate these stresses, indicating that plants may be able to develop normally in adverse conditions. The aim of this study was to examine the effects of graphene oxide (GO) on the germination of Persian clover seedlings under salt stress conditions. Following sown on substrate paper, seeds were tested after exposure to different concentrations of graphene oxide (0, 125, 250, or 500 mg L-1 GO), sodium chloride (0; -0.1; -0.2; -0.3, or -0.4 MPa NaCl) and/or GO + salt concomitantly, and then stored for 7 days in a germination chamber at 20°C in the presence of light. Seed germination and growth parameters of seedlings were determined. Graphene oxide demonstrated protective effect against salt stress as evident by no marked adverse effects on seed germination where GO blocked the salt-induced reduction in germination. The results obtained provide references for the safe application of nanomaterials and emphasize the significance of GO as a promising material for reducing the toxicity of salts in agriculture. [ABSTRACT FROM AUTHOR]

Canola (Brassica napus) is a significant oilseed crop in the world, including in Pakistan. Increases in global temperatures will likely affect future plant species distribution, and could influence the survivability of individual species because of the relationship between temperature, germination and dormancy. The objective of this study was to improve heat tolerance in canola with the foliar application of sulfur. Therefore, a pot study was performed in a growth room at the Institute of Horticultural Sciences, University of Agriculture Faisalabad in 2017-2018 under controlled conditions. Two varieties of canola, i.e., Hyola-401 and 45S42, two levels of foliar sulfur (S0= 0ppm and S1 500ppm) treatments, and two temperature levels (T1=8°C and T2=288°C) were studied. Heat stress was imposed at the time of anthesis (55-60 days after emergence). Collected data indicated that morphological characters such as root shoot length and their fresh and dry weight showed better performance where foliar sulfur was applied either in heat stress as well as in control conditions where no heat stress was imposed. The photosynthetic rate (6.21 m mole CO2 m-2/sec), stomatal conductance (0.12 m mole CO2 m-2/sec) and intercellular CO2 concentration (346.13 m mole CO2 m-2/sec) were improved in sulfur treatments under heat stress conditions while transpiration rate (0.51 mol H2O m-2 s-1) was decreased with foliar application of sulfur. Similarly, yield and yield components (No. of siliques per plant (23), No. of seeds per siliqua (20), 1000 seed weight (3.53 g) and overall yield (2.11 t/ha) increased where foliar sulfur was applied @ 500ppm. Overall results concluded that the foliar application of sulfur may be helpful for plant tolerance against heat stress by improving the physiological attributes and yield characters in canola. Moreover, among the genotype of Brassica napus L, Hyola 401 performed better in comparison with genotype 45S42 where foliar applied sulfur under heat stress conditions. [ABSTRACT FROM AUTHOR]