Phytosphere management for enhancing root yield and quality in a highly traded medicinal plant Desmodium gangeticum (L.) DC.

Phytosphere management studies for Desmodium gangeticum (L.) DC., an essential herbal remedy used in the Ayurvedic, Siddha, and Unani medical systems, were carried out at AICRP on MAP and B, College of Agriculture, Kerala Agricultural University. Treatments for standardizing shade requirements were 25% shade, 50% shade, 75% shade, and completely open growing conditions. The organic manuring treatments included basal application of FYM @ 10 t/ha, FYM @15 t/ha, vermicompost (to supply N equivalent to FYM 10 t/ha), vermicompost (to supply N equivalent to FYM 15 t/ha), coir pith compost (to supply N equivalent to FYM 10 t/ha), coir pith compost (to supply N equivalent to FYM 15 t/ha) and absolute control. Under 75% shade, the highest root production of 7589 kg/ha was observed. The lowest root yield was produced in the open condition (49% lower than the treatment with the highest yield). According to the findings, D. gangeticum could be used as a component in agroforestry systems with a high shade intensity. The root yields were comparable under 50 and 25% shaded conditions. The basal application of farm yard manure at 10 or 15 t/ha produced the highest root yield and total alkaloid content among organic manures. After two years of the experiment, the soil nutrient status revealed a decrease in the amounts of available nitrogen, phosphorus and potassium compared to the starting level. The absolute control showed the most significant nutrient depletion, emphasizing the importance of providing crops with manures or fertilizers.