Green Agricultural Techniques: Effects of Biochar and <i>Azospirillum</i> on Cucumber Growth and Fruit Quality

Bioresources play a crucial role in promoting sustainable agriculture by enhancing crop performance and reducing reliance on conventional fertilizers. This study investigated the impact of biochar and Azospirillum inoculation application on the growth and fruit quality of cucumber under greenhouse conditions. Thus, cucumber seedlings were grown when biochar was applied to the soil at rates of 0, 5, 10, and 20 tons/ha, and Azospirillum inoculum was inoculated at concentrations of 0, 5, and 10 mL/plant. Overall, sole biochar and/or Azospirillum application improves the plant growth and fruit quality. Interestingly, the integration of 5 tons/ha biochar and 10 mL/plant Azospirillum significantly enhanced plant performance and physiology; including stem diameter (15.66 mm), plant fruit number (46.08), plant fruit weight (5.51 kg/plant), total marketable yield (7.23 ton/grh), total polyphenol content (TPC: 220.06 μg GAE/g FM), total antioxidant activity (TAA: 2.84 μg/g FM) and mineral content: Nitrogen (3.26%), potassium (4.76%), and calcium (0.78%). Control plants without biochar and Azospirillum application exhibited the lowest performance. The study highlights the synergistic benefits, improving crop productivity and fruit quality while reducing the use of synthetic fertilizers. Integrating biochar and Azospirillum supports optimized plant production and environmentally sustainable farming practices.