Trials Test Lettuce Tipburn Sensitivity in Different Cultivars

Posted by Brian Sparks|May 31, 2023

Tipburn in lettuce is caused by calcium deficiency often seen when plants are grown quickly under optimum environmental conditions. The deficiency is also known as “localized” around young leaves at the shoot tip.

Tipburn occurs even with sufficient calcium fertilization of the whole plant. While the symptom is well described and mitigation methods are discussed (e.g., Mattson, 2015; Kubota et al., 2023), cultivar-specific tipburn sensitivity is not well documented. Specifically, comparisons among various cultivars supplied by different seed companies under growth conditions inducing tipburn are helpful for growers.

In general, conditions that promote overall plant growth (high light, high CO₂) yet suppress plant transpiration rate (low air circulation, high humidity) are known to increase the risk of tipburn. In addition, low humidity (high VPD) during nighttime increases tipburn risk in some cases. This is because low humidity at night promotes nonstomatal transpiration (loss of water from leaf surface), reducing xylem pressure and calcium supply to the shoot tip at night.

A recent e-GRO alert compiled by The Ohio State University’s Chieri Kubota and John Ertle outlines a trial conducted on 20 selected lettuce cultivars to test tipburn sensitivity. Seedlings were grown for 14 days prior to transplanting into hydroponic nutrient film technique (NFT) channels to assess the tipburn sensitivity for the following 28 days.

Learn more in the original e-GRO alert here.