Growth, Oil Yield, and Ion Partitioning in Basil Grown on Sodic Soils

Abstract

A field experiment was conducted on sodic soil during its rainy seasons of 2004 and 2005 to evaluate five germplasms of Ocimum basilicum (viz. CSLT 5, CSLT 9, CSLT‐12, CSLT‐12‐1, and CSLT‐13) for their growth performance, their oil yield, chemical constituents of their oil, and ion‐partitioning characteristics in different parts of the plants. The highest shoot yield was recorded in CSLT‐12, followed by CSLT‐9 and CSLT‐13. The highest oil yield was recorded in CSLT‐13, followed by CSLT‐12‐1. This indicated that a high herbage yield does not always result in a high oil yield. Germplasm CSLT‐12 and CSLT‐12‐1 seemed to have better adaptation in sodic soil then other germplasms on the basis of root architecture and root density. Germplasm CSLT‐5 was of the linalool chemotype, yielding 62.36% linalool in oil, whereas CSLT‐13 and CSLT‐9 were methyl chavicol chemotypes, yielding 69.59% and 56.98% of methyl chavicol, respectively. Germplasms CSLT 12 and CSLT 12‐1 are intermediate types that yielded 48.86% of methyl chavicol and 43.37% of linalool. The root, stem (main branch), and laterals (primary branches) were better sodium (Na)+accumulators then leaves and inflorescences. On the other hand, leaves were better chloride (Cl⁻) accumulators than roots. A higher K⁺/Na⁺ ratio was found in the immature leaves than in the matured leaves.

Keywords:

• Chemotype
• ion partitioning
• oil yield
• sodic soil
• sweet basil