Abstract:
Curry leaf (Murraya koenigii) is a valuable plant for both culinary and medicinal purposes,
preliminary due to its unique aroma, flavour and bioactive compounds. This semi-hardwood
species in tropical and subtropical regions, however faces challenges in conventional propagation
due to bacterial, fungal and viral infections. These pathogens reduce yield and disrupt genetic
fidelity, affecting desirable traits such as aroma, disease resistance and overall vigor. Although,
seed propagation is preferable to vegetative methods, it remains susceptible to contamination. In
vitro seed culture presents a viable solution by enabling seed sterilization and cultivation in a
controlled, aseptic environment, thereby eliminating external and some internal contaminants.
This approach supports the propagation of disease-free, true-to-type seedlings and helps
conserve elite genotypes. To develop a standardized in vitro seed culture protocol, seeds were
collected from fully ripened berries of premium, export-grade curry leaf plants in Jaffna. A total
of 108 replicates were used in the experiment applying 10% and 15% Clorox concentrations with
three exposure times: 10, 15 and 20 minutes. The most effective treatment was 15% Clorox for
20 minutes, yielding the highest survival and contamination-free rate of 78% (P < 0.05).
Germinated seedlings were then cultured for shoot proliferation under various hormonal
treatments, including 2.0 mg/L, 2.5 mg/L, and 3.0 mg/L 6-Benzylaminopurine (BAP) combined
with 0.5 mg/L Naphthaleneacetic acid (NAA). Among them, 2.5 mg/L BAP with 0.5 mg/L NAA
produced the maximum number of shoots per explant (6) after eight weeks, significantly
outperforming other treatments (P < 0.05). These findings, validated through SAS software using
ANOVA and Duncan Multiple Range Test (DMRT) analysis, demonstrate that in vitro seed culture
with optimized protocols enables large-scale propagation of genetically stable, disease-free curry
leaf plants, boosting both commercial viability and export potential.
