Basil (Ocimum sp.), belonging to the mint family, Lamiaceae (Labiatae), is a popular herb grown for the fresh market or for its dried aromatic leaves, which are used as a spice or in potpourris. In Asian countries, basil, particularly O. tenuiflorum, is better known as a medicinal plant species used for treating ailments ranging from colds to complex diseases such as cancers and diabetes. In the United States, however, it has a limited acceptance as a fresh-market herb. There is much potential for developing basil as a medicinal plant to cater to the growing herbal medicinal products industry. A field trial was therefore conducted to determine optimum date of planting basil in Alabama. Six-week-old seedlings were transplanted from the greenhouse into field plots arranged in a split-plot design with four replications. Planting dates at monthly intervals beginning in April were the main plots and three Ocimum accessions, Ames 23154, Ames 23155, and PI 288779 were sub-plot treatments. The accessions were compared for growth, leaf area development, light interception, canopy cover, and dry matter accumulation and partitioning pattern over planting dates. Ames 23154, with greater canopy cover (98.5%) and photosynthetically active radiation interception (96.1%), also produced higher total plant biomass than other accessions. Accession PI 288779 appeared to partition greater dry matter to leaves, which are the primary source of bioactive compounds in basil. Among planting dates, second (May) date of planting appeared to be optimum for both total biomass and leaf dry matter production. Genotypic variation f or dry-matter partitioning and relationships among agronomic parameters as influenced by planting date will be discussed in this presentation.
Cedric A. Sims and Srinivasa R. Mentreddy
Rao Mentreddy, Cedric Sims, Usha Devagiri and Ernst Cebert
Basils (Ocimum species) of the mint family Lamiaceae are well known for their multiple uses as culinary, aromatic, and medicinal plants worldwide. Basils are integral components of Asian and Mediterranean cuisine and are also widely used for treating diabetes and cancers. Basil has a limited acceptance as a culinary herb in the United States. The potential exists for development of culinary, medicinal, aromatic, and ornamental basil cultivars for production in the southeastern United States. In a preliminary field trial, 84 accessions belonging to six species of the genus Ocimum were evaluated for agronomic parameters in single-row plots. Wide variations exist between and within species for all agronomic traits studied. The mean percent emergence between species ranged from 60.0% for O. americanum var. americanum to 100.0% for an unknown species from Italy and O. campechianum. The aboveground fresh biomass per plant ranged from 424.0 g for O. sellol to 1450.3 g for the unknown Italian accession. The unknown Italian accession produced more branches per plant and also had the highest root, leaf, stem, and inflorescence fresh and dry weights among species. Ocimumsellol plants emerged late, had a slower rate of emergence, and produced a lower total biomass than other species. Ocimumgratissimum partitioned a greater proportion of the total dry weight to leaves (37.9%) and roots (14.4%), whereas O. basilicum. O americanum var. americanum, and O. campechianum partitioned a greater amount of dry matter to inflorescence and the least to roots than other species. In this presentation, the agronomic traits and basil cultivars with potential for ornamental and medicinal purposes will be discussed.