Trade-offs of organic and organic-inorganic fertilizer combinations in tomato quality and yield: A global meta-analysis (1992-2021)

Tomato (Solanum lycopersicon) is one of the most traded vegetables in the world. Fertilizer application is essential to sustain high tomato yields. While there is often a strong emphasis on increasing yield, less attention has been given to the effect of fertilizers on tomato quality and plant characteristics. Here, our meta-analysis explored 313 published studies consisting of 9752 organic fertilizers and 5915 organic-inorganic fertilizer combinations from 353 sites globally. These studies indicated that organic fertilizers significantly improve tomato quality compared to inorganic fertilizers. These improvements included increases in sugars (0.38-12.0 %), aromatic volatiles (72.1 %), and brighter color (1.64 %) along with decreases in organic acids (-6.76 %), nitrates (-16.9 %), and disease incidence (-73.0 % to -45.3 %). However, there were also some undesirable outcomes, including decreases in fruit firmness (-2.99 %) and tomato yield (-5.50 %). Interestingly, relative to inorganic fertilizers, the organicinorganic fertilizer combinations significantly improved tomato yield (12.4 %) and morphological characteristics, including titratable acid (3.52 %), mean fruit weight (7.28 %), number of fruits per plant (5.58 %), fruit diameter (2.74 %), plant height (52.4 %), and plant dry weight (41.6 %). Our study also shows that greenhouse cultivation enhances tomato quality compared to field cultivation. We also highlight the importance of increasing the utilization of organic resources to achieve reduced fertilizer usage, cost savings, and improved agronomic efficiency.