Nutrient management through organics, bio-fertilizers and crop residues improves growth, yield and quality of sacred basil (Ocimum sanctum Linn)

Sacred basil / Holy basil (Ocimun sanctum Linn) is a sacred plant widely used in pharmaceutical / cosmetic industries and is known for its varied medicinal properties. In order to study the influence of organic sources of nutrients on growth, yield and quality of sacred basil (Purple type), a field experiment was conducted at the ICAR-Directorate of Medicinal and Aromatic Plants Research, Boriavi, Anand, Gujarat for two consecutive seasons during 2015-2016. The experiment was devised in split plot design with three main plots (no organic/fallow, green manuring with cowpea (Vigna unguiculata (L.) Walp.) and crop residue of cluster bean (Cyamopsis tetragonoloba L. Taub) and seven sub plots (Control / no FYM (Farm yard manure), 50% N equivalent through FYM, 75% N equivalent through FYM, 100% N equivalent through FYM, 50% N equivalent through FYM + Arka Microbial consortia (AMC), 75% N equivalent through FYM + AMC and 100% N equivalent through FYM + AMC) in three replications. Results revealed that different plant growth parameters with respect to plant height, plant spread and number of branches and yield parameters such as dry herb yield, and essential oil content of pooled mean of two harvests (5.03 t ha(-1), 1.35% and 6.79 kg ha(-1), respectively) were recorded maximum in the treatment which received cluster bean crop residue. Among sub plot treatments, application of 100% N equivalent through FYM + AMC (N fixing, P & Zn solubilising and plant growth promoting microbes) recorded maximum dry herb yield (6.30 t ha(-1)), essential oil content (1.71%) and essential oil yield (10.79 kg ha(-1)) for the pooled mean of two harvests. Application of different crop residues significantly improved organic carbon (SOC) and available nutrient contents in soil, improved available nitrogen, phosphorus and potassium contents, soil microbial biomass (MBC) and dehydrogenase activity (DHA) compared with control. With these results, it can be concluded that incorporation of cluster bean crop residue prior to transplanting and application of 100% N equivalent through FYM + Arka microbial consortia could be recommended as organic production technology in sacred basil to obtain higher herbage yield and quality.