Medicinal Plants - International Journal of Phytomedicines and Related Industries
SCOPUS
  • Year: 2023
  • Volume: 15
  • Issue: 3

Carbon stocks, nutrient uptake pattern and soil health indicators in response to light level and nutrient source in Bacopa monnieri L.

ICAR-Indian Institute of Horticultural Research, Bengaluru-560 089, Karnataka, India

*Corresponding author e-mail: g.smitha@icar.gov.in, smithagingade@gmail.com

Online Published on 20 September, 2023.

Abstract

Bacopa monnieri L. is a perennial medicinal herb having considerable global and domestic demand. The 2-yr study at Bengaluru, India (2017-2019) investigated the influence of light availability and organic nutrition on carbon accumulation, soil fertility, soil microflora and economic benefits in B. monnieri. Significantly higher above ground carbon stocks were noticed in 35% shade (7.76 t ha-1) than in 50% shade (7.43 t ha-1) and full sunlight (6.71 t ha-1). The carbon accumulation in foliage (7.78-8.03 t ha-1) increased significantly due to addition of 100:26:50 kg NPK ha-1 (recommended level) and recommended NPK+10 t Farmyard Manure (FYM) ha-1. Cumulative N uptake was more (226.6 kg ha-1) than nutrient addition through fertilizers and organic manures (177 kg ha-1). The cumulative P uptake (44.3 kg ha-1) was less than nutrient addition through direct sources (59.5 kg ha-1). The difference between K uptake (314.5 kg ha-1) and K addition through different sources (97 kg ha-1) was considerable. Among nutrient levels, the K uptake was significantly higher in integrated nutrient treatment of 100:26:50 kg NPK + 10 t FYM ha-1 (357.7 kg ha-1) than in nutrient levels of 75 kg N through FYM and 50 kg N through vermicompost (VC). Overall, there was an increase in soil pH, Soil Organic Carbon (SOC) and soil test P and decrease in electrical conductivity (EC), and available N and K during the experimental period. The SOC and nutrient availability were unaffected by light availability and nutrition except that of soil test K. The microbial proliferation was significantly higher in full sunlight condition than in 35% and 50% shade levels. The microbial count was reduced significantly due to application of 100:26:50 kg NPK ha-1 than in higher organic nutrient levels. The results suggest that B. monnieri can be grown both in open-field or 35% shade and optimum nutrition is important for better soil health.

Keywords

Total carbon stocks, Nutrient uptake, Soil organic carbon, Available nutrients