Destructive harvest validation of high-throughput measurements show that water use efficiency is unaffected by moderate drought in tobacco

Researchers have validated that high-throughput, non-destructive measurements can accurately determine water-use efficiency (WUE) in tobacco plants, even during drought conditions. Traditionally, WUE has been calculated through destructive harvests, measuring the ratio of plant biomass to water lost through transpiration. However, new high-throughput phenotyping techniques allow for repeated, non-destructive estimation of biomass and WUE, raising the need for statistical validation.

To validate these digital measurements, researchers compared biomass determined point clouds from multispectral camera scanners against destructive harvests in eight Samsun tobacco harvests, conducted under both drought and high-water conditions. The results showed no significant differences between the digital and destructive measurements for either biomass or WUE, as determined by the coefficient of variation (CV).

This indicates that digital measurements can effectively replace destructive ones in assessing plant performance.

The study further revealed that drought-stressed plants were significantly smaller and used less water than their high-water counterparts from Harvests 4 through 8. However, there were no significant differences in the ratio of evapotranspiration to leaf area or WUE, suggesting that drought plants simply grew smaller and consumed less water than the plants with abundant water.

This work confirms that non-destructive digital point measurements coupled with continuous gravimetric determination of water use provide a reliable and efficient method for estimating WUE in high-throughput measurements across the entire plant life cycle.