Assessing the impact of organic mulches on weed control, crop growth, herbage yield and triterpenoids yield of Centella asiatica L. under western ghats region of Karnataka

Indian pennywort (Centella asiatica L.), is a valuable medicinal herb known for its bioactive compounds, particularly triterpenoids; however, its productivity is significantly hindered by weed competition, necessitating effective weed management strategies. An experiment was carried out at College of Horticulture, Mudigere, during 2023-24 to evaluate the effectiveness of organic mulches on managing weeds and its impact on crop growth, herbage yield and bioactive compounds of Indian pennywort. Among the different organic mulches evaluated, the treatment T₄ (Areca husk + one hand weeding @ 45 DAT) recorded the lowest weed density (34.00/m²), dry weight of weeds (2.51 g/m²), and higher weed control efficiency (94.93%) at 60 days after transplanting (DAT), along with weed index of 6.78 per cent. Among various mulches, the treatment T₄ (Areca husk + one hand weeding @ 45 DAT) also recorded highest values for all the growth parameters studies such as stolon length (113.65 cm), rosette length (23.75 cm), rosette diameter (20.77 cm), number of leaves per rosette (13.33), leaf area (21.61 cm²) at harvest and total chlorophyll content of 3.53 mg/g at 120 days after transplanting. Additionally, T₄ also recorded the maximum fresh (1232.67 g/m² and 12.33 t/ha) and dry herbage yield (223.44 g/m² and 2.23 t/ha) with the significantly highest total triterpenoids yield (77.91 kg/ha) over the rest of the mulching treatments studied. However, the lowest fresh (4.98 t/ha) and dry herbage yield (0.76 t/ha) and total triterpenoids yield (27.46 kg/ha) was recorded in the treatment T₇ (weedy check). Hence, it can be concluded that T₄ proved to be a promising treatment to enhance the weed control, crop growth, herbage yield, and bioactive compounds in Indian pennywort.