Crop productivity and energy indices of tomato (Solanum lycopersicum) production under naturally-ventilated poly-house structures in north-western India

Crop geometry greatly impacts tomato (Solanum lycopersicum) production under naturally-ventilated poly-house (NVPH) structures exerting significantly energy footprints. We compared agronomic attributes and energy indices of tomatoes established at different crop geometry (viz. 45 × 45, 60 × 45, 75 × 45 and 90 × 30 cm) under NVPHs. A spacing of 60 × 45 cm exhibited significantly (p < 0.05) higher polar and equatorial diameter, compared with narrower (45 × 45 cm) and widest (90 × 30 cm) spacing. Plant height exhibited a sigmoidal growth pattern across crop geometry. Fruit yield varied significantly (p < 0.05) with fruit size and crop geometry; with lower yields for smaller-sized tomatoes (<25 g) at narrower spacing, while higher yields for large-sized tomatoes (>90 g) at wider spacing. At 60 × 45 cm spacing, fruit yield reached 122.4 Mg ha−1 with total energy input of 44.7 GJ ha−1, energy output of 97.9 GJ ha−1 achieved with specific energy and energy productivity of 0.46 MJ kg−1 and 2.49 kg MJ−1, respectively. Cumulative energy gain was highest at 60 × 45 cm, indicating potential for improved energy efficiency in tomato production. These results showed the highest proportion of direct and non-renewable energy across crop geometry. Study underscores the significant impact of crop geometry on tomato production and energy efficiency in NVPH structures, providing valuable insights for optimizing cultivation practices and resource management.