Late-season heat stress (LSH) is a limiting factor for wheat production. Besides, low zinc and poor protein diet usually is a problem in low-income countries. The primary calorie source in such countries is prepared from bread. This study aims to mitigate heat stress by zinc and nitrogen application and improve zinc and protein content in wheat grain. We did the field experiments as a split-split-plot based on a randomized complete block design with four replications to assess zinc and nitrogen’s possible mitigation effect on LSH and protein and zinc enrichment of wheat grain during two years. Factors included LSH by delay in planting date (optimum, late, and very late) as the main plot, nitrogen (0, 75, 150, and 225 kg ha–1) in subplots, and zinc (0, 10, and 20 kg ha–1) as sub-subplots. We measured yield, yield components, physiological traits, zinc, and protein contents in the grain. Results showed that the highest relative water content and cell-membrane thermal stability were attained at the optimum planting date, 150 kg N ha–1 and 20 kg Zn ha–1. The maximum chlorophyll a and carotenoids contents in wheat cells were recorded in the optimum planting date, 225 kg N ha–1, and 20 kg Zn ha–1. Heat stress reduced the grain yield. In the second year of the experiment, the grain number per unit area was more than that of the first year; however, the highest grain yield was achieved in the first year owing to the higher mean grain weight. Nitrogen application decreased the adverse effects of heat stress on grain yield by increasing the grain number. Zinc application diminished the adverse effects of heat stress by increasing the mean grain weight. The adverse impact of the LSH on grain yield was more than that of biological yield. Heat stress reduced the hectolitre weight and zinc content of the grain. Meanwhile, it increased grain protein. In general, under LSH, the application of 225 kg N ha–1 and 20 kg Zn ha–1 can reduce the adverse effects of heat on the grain quality and quantity.

A laboratory experiment was carried out to assess the possibility of decreasing the negative effects of salinity on seed germination and early seedling growth of canola by hydro-priming of seeds. A 7×5 factorial experiment based on completely randomized design was employed to compare the treatments. Seed priming comprised 0.0, 4.0, 8.0, 12.0, 16.0, 18.0 and 24.0 h seeds soaking in distilled water, and salinity stress was simulated by the solutions of 0.0, 25.0, 50.0, 75.0 and 100.0 mM NaCl. Germination percentage and uniformity, germination speed and seedling dry weight were measured as germination performance indicators. Results showed that all traits were significantly affected by salinity stress and seed priming. Germination uniformity and seedling dry weight were affected by the interaction of salinity × seed priming. Germination percentage and speed were slightly affected by the interaction of salinity × seed priming. However, it was not significant. Increasing in salinity stress from control to the highest level (125 mM NaCl) resulted in 26% reduction of germination percentage of rapeseed. However, germination speed was a trait showing higher sensitivity to the salinity stress. The difference between control treatment and the highest salinity stress in terms of germination speed was 45%. Hydro-priming improved germination percentage and speed of rapeseed seeds. The highest germination percentage and speed was observed in the treatment of 24 h which was not significantly different with 20 h hydropriming. Germination percentage and speed of rapeseed improved 25 and 30 by hydro-priming of seeds, respectively. Generally, the length of hydro-priming solutions improved the performance of seeds and seedlings of rapeseed. Higher levels of hydro priming duration reduced negative effects of sever salinity stress, where there was no significant difference between two last salinity levels in terms of salinity.