o:8574 Comparative Analysis of LettuceMorphological and Physiological Traits: Effects of Cultivar, Biofertiliser, and Seasonal Variations in Different Soil Types en Abstract: A multi-factor analysis of cultivar, biofertiliser, and growing season was conducted to optimise lettuce agronomic and quality traits in diverse soil conditions. The goal was to identify soil differences and offer practical recommendations to improve lettuce traits and quality for farmers and the processing industry. The study employed a complete block design with four treatments, three involving biofertilisers, applied to six lettuce cultivars grown in two contrasting soil types- Mollic Gleysol (Calcaric)-GL and Hortic Anthrosol (Terric, Transportic)-AT, across three consecutive greenhouse seasons (autumn, winter, and spring). Biofertilisers were applied to the soil before transplanting and foliarly during the growing cycle, with four of the following treatments: control (no fertilisation), a fertiliser containing beneficial microorganisms, a Trichoderma-based fertiliser, and a combination of both. In GL soil, all biofertiliser treatments increased rosette height, leaf number, and stem length, whereas in AT soil, all morphological parameters declined significantly. The green cultivars ‘Aquino’ and ‘Kiribati’ showed superior morphological performance, particularly in spring and winter. Rosette fresh weight, a key indicator of plant biomass, reached 236.4 g in ‘Aquino’ grown in GL soil, and 208.6 g in ‘Kiribati’ grown in AT soil. Dualex™ leaf sensor measurement indicated that ‘Aquino’ exhibited the highest nitrogen balance index (NBI), while the red cultivar ‘Gaugin’ recorded the highest chlorophyll, flavonoid, and anthocyanin contents. Combined fertilisers increased NBI by 6.3% and chlorophyll by 6.8% in GL soil. Trichoderma fertiliser alone raised NBI by 6.8% in GL soil, whereas in AT soil, plants accumulated more flavonoids and anthocyanins (by 9.2% and 8.5%). Optical parameters were highest in autumn. The three-factor experiment demonstrated that cultivar, biofertiliser, and growing season significantly influenced the majority of measured traits. Correlation analysis revealed that rosette fresh weight was positively associated with NBI but negatively correlated with quality-related traits. Based on these findings, cultivars ‘Aquino’, ‘Kiribati’, and ‘Gaugin’ are recommended for both farmers and the processing industry to improve lettuce production quantity and quality. Overall, cultivar, biofertiliser, and season strongly influenced the measured parameters, underscoring the importance of tailoring biofertiliser application to soil type and season to achieve optimal production outcomes. Lactuca sativa; biofertiliser; seasonality; soil type; agronomic parameters; optical sensor parameters 1552099 10.3390/horticulturae11111372 2025-12-02T13:12:39.651Z 44 no 46 Milica Stojanović Institute for Multidisciplinary Research, University of Belgrade 46 Zoran Dinić Institute of Soil Science 0000-0002-6666-0875 46 Jelena Dragišić Maksimović Institute for Multidisciplinary Research, University of Belgrade 46 Vuk Maksimović Institute for Multidisciplinary Research, University of Belgrade 46 Zorica Jovanović Faculty of Agriculture, University of Belgrade 46 Ðorđe Moravčević Faculty of Agriculture, University of Belgrade 46 Slađana Savić Institute for Plant Protection and Environment application/pdf 893105 https://unilib.phaidrabg.rs/o:8574 no yes 1 70 92000001 71A05 Horticulturae 2025