2019 ASHS Annual Conference

Celery (Apium graveolens) is grown throughout the central coastal region of California. This shallow rooted vegetable is highly sensitive to soil moisture stress and is irrigated by a variety of methods, including drip, furrow, and sprinkler. We conducted a replicated field trial in 2018 to investigate yield response of drip-irrigated celery to applied water volume. Irrigation treatments were 50, 75, 100, 125, and 150% of estimated crop evapotranspiration (ETc), which was based on a crop coefficient model and reference evapotranspiration data from a nearby weather station. Irrigation treatments were replicated 6 times following a randomized complete block design. Transplants were established with sprinklers. Irrigation treatments commenced 22 days after transplanting (DAT) when the drip tape was installed. The crop was irrigated 3 times per week. Nitrogen fertilizer, totaling 380 kg/ha, was applied through the drip system once per week. Treatments were evaluated for commercial yield 85 and 93 DAT, and above ground biomass was evaluated 87 DAT. The 100% ETc treatment received a seasonal total of 34 cm of water and yielded 83 Mg/ha 93 DAT which was 10 Mg/ha higher than the average yield for the Salinas Valley in 2017. The highest commercial yield was measured in the 125% and 150% ETc treatments and equaled 102 and 108 Mg/ha, respectively, at 93 DAT. Seasonal applied water for the 125% and 150% treatments was 42 cm and 48 cm, respectively. The 150% ETc treatment had a higher incidence of pith breakdown and basal rot than the 100% ETc treatment. Yields from the 50% and 75% treatments fell below the Salinas Valley average. Above ground fresh and dry biomass increased with increasing applied water volumes, with a maximum of 165 Mg/ha of fresh biomass for the 150% ETc treatment.