Opportunities and risks with early sowing of sunflower in a salt-affected coastal region of the Ganges Delta

On low-lying land in the Ganges Delta, waterlogging, salinity, and poor soil structure are constraints to intensifying cropping systems. Early sowing of dry season (rabi) crops this area is hypothesized increase yield potential because current late exposes crop less favourable temperature conditions, dryness, salinity stresses. Field experiments were conducted over 2 years identify opportunities challenges early between mid-November mid-December for maximizing sunflower Southern Bangladesh. Sunflower was dibbled into untilled wet on five occasions (23 30 November 10, 20, December 2016–2017 25 November, 14 December, 10 January 2017–2018), with two mulching treatments (rice straw at ~ 5 t ha?1 15–20% rice residue retention). Sowing before 15 associated larger heads, more seeds per head, greater seed weight, higher grain (3.5–4 ha?1) first year, but also risky since, second sown hampered by heavy rainfall, which depressed compared December. Increased from water, lower solute after Lower increased grain-filling stage. The mulch significantly improved water availability, reduced potential, year. In paper, we show time that Delta has gain benefits earliest sowing, growers will need manage risk loss due waterlogging.