Organic nutrient interventions for improving biochemical quality of sacred basil

Abstract

Sacred basil is a medicinal and aromatic plant valued for its therapeutic properties, largely attributed to its rich biochemical constituents such as chlorophyll and carotenoids. A field experiment entitled “Organic nutrient interventions for improving biochemical quality of sacred basil” was conducted during summer-2024 at MHREC, University of Horticultural Sciences, Bagalkot, Karnataka, to assess the effect of organic inputs on chlorophyll and carotenoid content. The experiment was laid out in a Randomized Block Design with 13 treatments and 3 replications, including combinations of vermicompost, microbial consortium, Panchagavya, humic acid, Jeevamrutha and an inorganic control. Pigment contents were estimated at 45 DAP and at harvest using the DMSO extraction method followed by spectrophotometric analysis. Significant differences were observed among treatments for chlorophyll a, chlorophyll b, total chlorophyll and carotenoids. The treatment T6 (100% N through Vermicompost + Microbial consortium @ 15 kg ha-1 + Panchagavya @ 3% + Humic acid @ 2.5 L ha-1 + Jeevamrutha @ 500 L ha-1) recorded the highest pigment values with chlorophyll a (2.29 and 1.91 mg g-1), chlorophyll b (0.93 and 0.78 mg g-1), total chlorophyll (3.21 and 2.69 mg g-1) and carotenoids (1.56 and 1.36 mg g-1) at 45 DAP and harvest, respectively, followed by T12 and T2. The lowest pigment values were recorded in T13 (only 100% NPK). The enhanced pigment levels can be attributed to better nutrient uptake, hormonal stimulation and photosynthetic efficiency under organic inputs. The study highlights that integrated organic nutrient management is a sustainable approach to improving the biochemical quality and productivity of sacred basil.