Fertilizer and plant-growth-promoting microorganisms (PGPMs) both benefit crop growth; however, little is
known about the interaction effects when they are combined. This study assessed the effect of PGPMs and
fertilizer on plant growth, foliar chemistry, and subsequent insect feeding. Cabbage and tomato plants were
inoculated with PGPMs (fungi and bacteria) and various levels of fertilization. Plant growth parameters (fresh
weight, dry weight, and leaf area) and foliar chemistry (water content, protein content, and polyphenol oxidase
activity) were then analyzed. In addition, foliage was also fed to the third instar larvae of Spodoptera litura to
evaluate foliage quality. The results indicated that plant performance differed significantly among treatments,
and the combined fungi Meyerozyma guilliermondii and fertilizer treatment promoted the greatest plant growth.
In summary, PGPMs and fertilization can have their owneffect; their interaction effect, however, need to be clarified.