Pot trials with Lactuca sativa (lettuce)

After the unsuccessful pot trials with Spinacea olaracea (spinach) as part of WP T2, D2.2, the experiment was repeated with Lactuca sativa (lettuce) under controlled conditions to determine fertiliser performance at a level of plant availability and to determine the nutrient use efficiency of the recycling-derived fertilisers and their blends. The experimental set-up consisted of seven treatments comprising of:

• Blank (no fertilisation)
• Control (synthetic NPK)
• Ammonium nitrate + synthetic PK
• Ammonia water + synthetic PK
• Concentrate after evaporation + synthetic N
• Ammonium nitrate + concentrate after evaporation (blend 1)
• Ammonia water + concentrate after evaporation (blend 2)

Except blank, all other treatments were done in two dosages:

• Optimal dosage (fertiliser advice of 200 kg ha^-1 N, 125 kg ha^-1 P₂O₅, 240 kg ha^-1 K₂O)
• Optimal dosage – 50%

The harvest of plants were done after 55 days and fresh weight of the samples were analysed. It was seen that the treatment with ammonium nitrate exhibited plants with the highest fresh weight. The harvested plants and soil from pots are yet to be analysed for other parameters.