Journal of Advances in Biology & Biotechnology

The aim of this study was to determine the combined effect of different substrates and time of application of nutrient at different concentration on growth parameters of Romaine long (green) lettuce. The experiment was conducted in semi-controlled naturally ventilated polyhouse for two years (2021-2022 and 2022-2023) during Rabi season at Department of Horticulture, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani (MH). The research was laid in a Factorial Completely Randomized Design, which is replicated twice with three factors i.e.  Factor A) consisted different substrates (S) (S₁: cocopeat, S₂: cocopeat + perlite (1:1 v/v), S₃: cocopeat + perlite (2:1 v/v) and S₀: soil), Factor B) levels of nutrient concentration (F) (F₁: 100%, F₂: 80% and F₃: 60%) and Factor C) application time interval (I) (I₁: one day interval, I₂: three days interval and I₃: six days interval). The nursery raising of lettuce was done under greenhouse in pro-trays and seedling are ready for transplanting one month after sowing. The result revealed that combined application of treatment T₆ [S₂F₁I₂] i.e. Cocopeat + Perlite (1:1) + 100% + Three days interval recorded maximum plant height (28.24 cm) and number of inner leaves (18.50) whereas maximum number of outer leaves per plant (5.35) was recorded in the treatment combination of T₁ [S₁F₁I₁] i.e.  Cocopeat + 100% + One day interval and T₅ [S₁F₁I₂] i.e. Cocopeat + 100% + Three days interval in pooled mean data at harvest. Further, the highest leaf area was (105.84 cm²) was observed in the treatment combination of T₃₃ [S₁F₃I₃] i.e. Cocopeat + 60% + Six days interval. The obtained result showed clear difference of lettuce growing under different substrates and time of application of nutrient at different concentration on growth parameters.