Effect of Microbial and Chemical Fertilization on Lentil Growth, Yield and Quality under Semi-Arid Conditions

Sustainable agricultural practices and effective plant nutrition strategies are increasingly important for both yield improvement and the conservation of natural resources. This study aimed to investigate the synergistic effects of microbial and chemical fertilization on lentil (Lens culinaris Medik.) growth, yield, and nutrient composition under the ecological conditions of Van, Türkiye. The experiment evaluated the interaction between Rhizobium leguminosarum (RHZ), phosphate-solubilizing bacteria strain (B), and nitrogen fertilizer (NF) across two growing seasons. The findings revealed that both year-to-year climatic variability and treatment combinations significantly affected plant performance. Among treatments, RHZ+NF+B consistently resulted in superior outcomes in biological and grain yields of 2992 and 1302 kg ha⁻¹, representing 19.5% and 28.9% increases over the control, respectively. This integrated approach also boosted grain N, P, and K contents by 11.5%, 34.6%, and 35%, respectively, thereby indicating improved nutrient uptake and mobilization. In contrast, combined application of NF with RHZ and B reduced yield productivity since nitrogen has inhibitory effect on nodulation and nitrogenase enzyme activity. Number of plants per square meter, which ranged from 55.3 to 120.8, was a key determinant of total biomass and pod number per plant, therefore, the higher emergence rates in the first season were likely driven by more favorable climatic conditions. Nutrient analysis showed that integrated microbial-chemical treatments enhanced macronutrient accumulation, however, micronutrient responses exhibited differences. Notably, Fe and Cu concentrations decreased in high-yielding plots, whereas Zn and Mn levels remained relatively stable. The study highlights the importance of tailoring nutrient input strategies to support both biological nitrogen fixation and optimal nutrient composition. It also reinforces the potential of integrated biofertilization practices in promoting sustainable legume production under semi-arid conditions. These results highlight balanced N fertilizer to support biological N2 fixation. Further research is recommended to focus on long-term soil health impacts the long-term impacts on soil health.