Enhanced Growth and Essential Oil Profiling of Coriander ( <i>Coriandrum sativum</i> L.) <scp> CO ₄ </scp> Under Biostimulant Application

ABSTRACT Coriander ( Coriandrum sativum L.), a widely cultivated herb in the Apiaceae family, is valued for its culinary, medicinal and essential oil properties. Enhancing the growth, yield and quality of coriander is of growing importance due to increasing demand in food and pharmaceutical industries. In recent years, biostimulants have emerged as promising tools in sustainable agriculture, known for their eco‐friendly nature. This study evaluated the effects of three biostimulants viz., Phytocil, humic acid and seaweed extract, on growth, yield and quality of coriander using RBD with eight treatments and three replications. Chlorophyll, protein and ascorbic acid contents were evaluated using SPAD, Folin‐Lowry and DCPIP methods, respectively. Biostimulant applications improved plant performance across all treatments, especially T3 and T4. Growth parameters like plant height (T4—61.33), branching (T3—13.55) and leaf area index (T4—0.1408) were enhanced with biostimulant applications. In terms of yield characteristics, T3 produced the highest number of umbels per plant (16.12), maximum seed yield (465.42 kg ha −1 ) and highest harvest index (32.50%), which is followed by T4. Biochemical analyses showed that T4 enhanced chlorophyll content (30.91 SPAD), ascorbic acid (27.78 mg 100 g −1 ), protein content (3.05%) and essential oil yield (0.43%), with T3 also performing strongly. GC–MS analysis of essential oil from Phytocil and humic acid‐treated plants identified 60 unique compounds, with 40 shared between the two profiles. Statistical and enrichment analyses revealed a significant difference in essential oil composition, with Phytocil promoting higher metabolite production. These results indicate the potential of biostimulants, especially Phytocil, for broader agricultural applications in coriander and other Apiaceae crops, improving productivity and maintaining quality standards.