Polysulphate® Lettuce Trial in Israel

25%

Yield Increase

Polysulphate fertilizer significantly increases lettuce fresh and dry biomass, and increases calcium and sulfur concentrations in the leaves.

Northern R&D Farm, Israel
2019

25%

Yield Increase

Key Conclusions

Polysulphate fertilizer significantly increases lettuce fresh and dry biomass by up to 25%, and significantly increases calcium and sulfur concentrations in lettuce leaves.

Objective

To evaluate Polysulphate as a calcium source for lettuce (Lactuca sativa), using a greenhouse soilless production system.

Trial Details

Trial station

Northern R&D Farm, Israel

Crop

Lettuce

Assessments

Total yield, and commercial yield

Treatments

  • The experiment was designed in complete random blocks, with 6 replicates consisting of 5 pots each.
  • Seeds were sown in June 2019, and harvest took place in July 2019.
  • Plants were grown under controlled greenhouse conditions in 4 L pots filled with perlite.
  • Treatments included 4 rates of granular Polysulphate: 0 (control), 0.25, 0.50, and 0.75 g/L that were thoroughly mixed with the perlite before planting.
  • Water used for irrigation was desalinated using reverse osmosis to a level of 0.6 mEq Ca/L.
  • Plants in all treatments were fertigated throughout the experiment with NPK 5:3:8 + MgSO4.
  • Irrigation was scheduled 3 times a day for 10 minutes per irrigation (approx. 1 L/day).

Treatments

  • The experiment was designed in complete random blocks, with 6 replicates consisting of 5 pots each.
  • Seeds were sown in June 2019, and harvest took place in July 2019.
  • Plants were grown under controlled greenhouse conditions in 4 L pots filled with perlite.
  • Treatments included 4 rates of granular Polysulphate: 0 (control), 0.25, 0.50, and 0.75 g/L that were thoroughly mixed with the perlite before planting.
  • Water used for irrigation was desalinated using reverse osmosis to a level of 0.6 mEq Ca/L.
  • Plants in all treatments were fertigated throughout the experiment with NPK 5:3:8 + MgSO4.
  • Irrigation was scheduled 3 times a day for 10 minutes per irrigation (approx. 1 L/day).

Results

  • Polysulphate application significantly increased lettuce fresh and dry biomass, adding up to 25% to the fresh weight of the plants.
  • Calcium and sulfur concentrations in the leaves were significantly higher with Polysulphate application, but no response was observed to the nutrient dose.
  • Polysulphate application can ensure enough available Ca to satisfy lettuce requirements and guarantee high produce quality.

 

Bar chart showing the effect of different granular Polysulphate concentrations (0, 0.25, 0.5, 0.75 g/L) on plant fresh weight (g/plant). The highest yield occurs at 0.5 g/L, resulting in a 25% increase compared to the control.

Polysulphate significantly increases lettuce fresh weight by up to 25%.

 

Bar chart showing calcium concentration (% of dry matter) in plants treated with different granular Polysulphate rates (0, 0.25, 0.5, 0.75 g/L). Calcium levels increased significantly with Polysulphate application, peaking at 0.25 and 0.5 g/L.

Polysulphate significantly increases the calcium and sulfur concentration in lettuce leaves.
Similar letters indicate no significant differences between treatments at p <0.05.

 

Polysulphate®

Exceptional natural multi-nutrient fertilizer

Granular Polysulphate 0-0-14

0-0-14 +TE See product