Flowering is the critical growth stage for adverse effects of salinity on the grain yield of sunflower

Crop sensitivity to root zone salinity can vary over time, which lead severe damage when high coincides with soil salinity. The variation in of sunflower during its growth cycle is unknown. Two pot experiments were conducted sand culture a complete nutrient solution. Solutions flushed through pots excess maintain specified salt concentrations the In Experiment 1, salt-sensitive stages determined by applying solutions an electrical conductivity < 0.7, 2, 4 or 8 dS m− 1 vegetative, flowering grain filling stages. most sensitive stage root-zone was exposing plants 10-day periods (< 8, 16 and 24 1) overlapping days starting from 13-leaf filling. both experiments, decreases seed yield associated exposure elevated EC period before opening disk flower ~ 95% anthesis, while least sensitive. decline correlated decrease mature number. Increasing increased area without seeds at centre disk. experiment measurements leaf ion photosynthesis suggested that Na+ toxicity decreased due availability photosynthate flowers. To maximise saline soils, it important minimise stress anthesis.