Nutrient Use Efficiency Lettuce
This study investigated the effect of Seasol, a seaweed extract, on lettuce growth under different rates of fertiliser. Lettuce was grown in pots in a greenhouse with 18 replicates per treatment. The experimental design successfully limited lettuce growth at lower fertiliser rates.
Seasol treated lettuce was 15% (P<0.05) heavier (fresh weight) than untreated lettuce at 75% fertiliser rate. This is supported by a 5% higher dry weight of Seasol treated lettuce compared to untreated lettuce. Head weights were higher in Seasol treated lettuce at 100%, 75% and 0% fertiliser rates.
Residual soil nitrate was higher in untreated lettuce compared to Seasol treated lettuce, showing greater nutrient (nitrate) uptake when Seasol is applied. Leaf nitrate was 96% higher in Seasol treated lettuce compared to untreated lettuce at the standard fertiliser rate.
Roots were longer in and heavier in Seasol treated lettuce.
Seasol application effectively improved the nutrient use efficiency of lettuce plants by increasing their growth and nutrient uptake. On average, Seasol-treated lettuce were larger, heavier, grew longer and heavier roots. However, there are some inconsistent trends between the fertiliser rates which would benefit from further research.
