Management of root rot (Rhizoctonia solani) of Ajwain

Ajwain (Trachyspermum ammi) is a valuable spice, medicinal and aromatic crop. The yield and quality of ajwain is adversely affected by root rot of ajwain caused by Rhizoctonia solani.A field experiment was conducted at MES, Vegetable Science, ANDUAT, Kumarganj, Ayodhya to evaluate the efficacy of different fungi-toxicants and bio-agents against the disease. Ten treatments, comprised chemical fungicides, biocontrol agents, organic amendments along with control, were tested for their efficacy against the disease.The results revealed that T7 (soil drenching with Tebuconazole 50% + Trifloxystrobin 25% WG @0.1%) was the most effective treatment, recorded lowest PDI (6.11%), highest PDC (68.79%), and highest yield (11.62 q/ ha). by T6 (Azoxystrobin + Difenoconazole) and T5 (Bascolid + Pyraclostrobin), which also showed significant disease suppression and yield improvement. Among bio-agents, T1 (seed + soil treatment with Trichoderma harzianum) showed moderate efficacy with a PDC of 24.15% and yield of 8.70 q/ha. The control (T10) recorded the highest disease incidence (19.54%) and lowest yield (7.92 q/ha). Overall, systemic fungicides, especially combination products, were more effective than bio-agents and organic treatments in managing root rot of Ajwain.