The spatial distribution patterns of five melon cultivars (Cucumis melo L. var. reticulatus) were evaluated by measuring XY coordinates of ripe fruit locations in the field. Fruit ripeness distribution over time was also evaluated for three cultivars by measuring the number of ripe fruit, fruit mass, and location over time. Spatial distribution curves for distances between fruit clusters and individual fruit from cluster centroids varied between clusters and were derived for each cultivar from the best fit curves based on chi-square analysis from the two-dimensional spatial fruit distribution. These equations can be used for predicting actual fruit locations in the field. Ripeness distribution patterns indicated that, while the exact duration of the effective harvesting period is cultivar-dependent, the ripeness trend for each of the cultivars was similar. Spatial distribution patterns vary among melon cultivars and must be recognized in the design of automated harvesting systems.
Yael Edan and James E. Simon
Denys J. Charles and James E. Simon
The curry plant [Helichrysum italicum (Roth) G. Don in Loudon ssp. italicum or H. angustifolium (Lam.) DC (Asteraceae)], a popular ornamental herb with a curry-like aroma, was chemically evaluated to identify the essential oil constituents responsible for its aroma. Leaves and flowers from greenhouse-grown plants were harvested at full bloom. Essential oils were extracted from the dried leaves via hydrodistillation and the chemical constituents analyzed by gas chromatography (GC) and GC/mass spectrometry. The essential oil content was 0.67% (v/w). Sixteen compounds were identified in the oil and included: neryl acetate (51.4%), pinene (17.2%), eudesmol (6.9%), geranyl propionate (3.8%),β-eudesmol (1.8%), limonene (1.7%), and camphene (1.6%). While the aroma of the curry plant is similar to that of a mild curry powder, the volatile chemical profile of the curry plant does not resemble that reported for commercial curry mixtures.
Ben H. Alkire and James E. Simon
A 500 liter (130 gallon) stainless steel steam distillation unit has been built to extract volatile essential oils from aromatic plants. A 1.5 m × 0.75 m dia. steam vessel (hydrostatically tested @ 125 psi) serves as the distillation tank. Low pressure or high pressure steam is supplied by a diesel fuel fired boiler of 10 horsepower. The steam vessel can hold peppermint from plots of 25 m2 and extract approximately 100 ml of essential oil per distillation. The size of the tub was designed to provide oil in sufficient quantity for industrial evacuation or for pesticide residue analysis. Following the distillation, the vessel can be disconnected from the cold-water condenser and rotated on swivels to a horizontal position, permitting easy removal and re-filling of plant material. The entire extraction unit (vessel, condenser, boiler and oil collector) is suitable for mounting upon a trader, making it transportable to commercial farms or research stations. The extraction of peppermint and spearmint oils using this new system will be presented.
Renee G. Murray and James E. Simon
Essential oil content of Ocimum basilicum, cv. sweet basil, increases with plant maturity. The increase in essential oil content may correspond to the formation of glandular trichomes during leaf expansion. Greenhouse grown plants were harvested every 2 weeks. Leaves were grouped according to size, examined with a stereo microscope, and trichome densities compared. Results indicate that trichome formation continues throughout leaf expansion. In young basil plants, leaves ranged in size from 2-30cm2 Highest density (416 trichomes/cm2) occurred in leaves 2–6c m2. Prior to open bloom, leaves ranged in size from 2-49cm2. Highest density occurred in leaves 18-24c m2. In flowering plants leaves ranged in size from 2-34cm2, yet there was NSD in trichome density in leaves of different sizes. Analysis of the entire leaf surface of plants at each harvest showed the greatest density of trichomes in plants at full bloom (280 trichomes/c m2). All leaves have visible glandular trichomes. These glandular trichomes are most likely formed both prior to and during leaf expansion.
Roberto F. Vieira and James E. Simon
To determine the mode of inheritance of citral, linalool, methylchavicol, and methylcinnamate in basil, controlled crosses were made between chemotypes rich in each of these constituents. Four stable Ocimum basilicum populations selected for high methylcinnamate (79%), methylchavicol (95%), linalool (82%), and citral (65%) respectively, served as parents. Crosses were made using chemotypes rich in terpenes (linalool × citral), in phenylpropanoids (methylchavicol × methylcinnamate), and a third that combines chemotypes from both biosynthetic pathways (linalool × methylchavicol). True hybrids were selfed in isolation and one hundred F2 plants were analyzed for their oil composition. The parents, the F1 hybrids and the F2 generation of all plants were evaluated in a field trial under identical environmental conditions. Plants were harvested at full flowering, and dried at 380 °C. Identification of essential oil constituents were confirmed by GC/MS. The F2 segregation data for each major oil constituent trait will be examined by c2 analysis tests. Preliminary results indicate that methylcinnamate segregates in a 3:1 ratio, and is a dominant major gene. In the two crosses using methylcinnamate chemotype as a female parent, the F2 population segregates in 80:22 and 65:28 methylcinnamate:non-methylcinnamate plant types, with P = 0.42 and 0.25 and c2=0.64 and 1.29, respectively. Analysis of the other crosses are being processed, evaluating qualitative and quantitatively the presence or absence of each constituent in their F2 population.
Mario R. Morales and James E. Simon
`African Beauty', a new ornamental camphor basil cultivar, was developed through three cycles of selfing and selection from USDA accession PI 500942, originally collected in Zambia, Africa. `African Beauty' was field-evaluated and compared with PI 500942 (the original population), PI 500954 (another accession from Zambia), a camphor cultivar from Companion Plants, and three other related lines in 1997 and 1998. Most commercial camphor basils are tall (50 to 60 cm), late-flowering, and unattractive. Our goal was to develop a new cultivar that had a short stature (≈40 cm), an early flowering, and an attractive appearance. The outcome was `African Beauty', which has the following characteristics: plant height: 30 to 35 cm, plant spread: 50 to 55 cm, leaf length: 6.3 to 6.7 cm, days to flower: 76 days, inflorescence length: 25 cm, essential oil yield: 3 mL/100 g dw. The essential oil of `African Beauty' is also highly aromatic, with 72% camphor, 12% camphene, and 9% limonene. The plant is a fast-growing, semicompact aromatic plant that produces small leaves and large quantities of long and slender inflorescences that, when fully developed, curve at the tip like the tail of a cat. Blooming usually lasts from 20 to 25 days, when the plant looks most beautiful. `African Beauty' is an attractive ornamental that would be excellent as a garden border plant, or as an indoor potted plant.
Mario R. Morales and James E. Simon
Liangli Yu, Mario Morales, and James E. Simon
Hydro-distilled essential oils from fresh and dry leaves and fresh and dry flowers of `Sweet Dani', a new ornamental lemon basil (Ocimum basilicum) cultivar with potential as a source of natural citral, were analyzed by GC and GC/MS. The essential oil contents were 0.18%, 0.19%, 0.30%, 0.28% w/w on a fresh weight basis of fresh and dry leaves, and fresh and dry flowers, respectively. Oils from leaves and flowers differed significantly in content and composition. The major constituents in dry leaf oil were neral 21.8% and geranial 33.5%. The major constituents in dry flower oil included: nerol 11.5%, neral 12.9%, geraniol 7.6%, and geranial 17.7%. Nerol (1.6%), and geraniol (0.4%) were very low in dry leaf oil. As citral is a combination of neral and geranial, the relative leaf and flower citral content is 55.3% and 30.6% of the total oil, respectively. Linalool and octanol were detected in flower oils only.
Roberto F. Vieira and James E. Simon
Ocimum species are largely used in Brazil both as a condiment and in traditional medicine against bronchitis, cough, and sorethroat in the form of tea or syrup. As little research has examined the natural products from Brazilian basil, 14 accessions of Ocimum, including O. basilicum (4), O. campechianum (3), O. gratissimum (6), and O. kilimandsharicum (1), collected in Brazil were grown in the Purdue Univ. greenhouse and upon maturity harvested, the volatile oil extracted and analyzed by GC/MS. Thirty-one constituents were identified. Three accessions of O. gratissimum showed high content of eugenol (40% to 66%), while the other accessions contained either high thymol (33%) or p-cymene (28% to 42%). The constituents of the single O. kilimandscharicum included 1,8-cineole (39%), methyl-chavicol (21%), and ß-bisabolene (23%). O. campechianum accessions contained either high 1,8-cineole (62%) or high ß-caryophyllene (79%). O. basilicum could also be separated chemically: a linalool:methyl chavicol type (47:28%); one methyl chavicol type (72%), and a third, methyl cinnamate (61%). One accession was identified containing >90% trans-methyl cinnamate, which crystallized during extraction. Plants rich in targeted compounds, such as the one with 90% trans-methyl cinnamate, can be used as source of germplasm for breeding and potential commercialization
Winthrop B. Phippen and James E. Simon
The importance of anthocyanins as a food coloring, UV protectant, inhibitor of pathogens, and medicinal compound has been well-documented, with more than 300 anthocyanin compounds being reported in plants. The Lamiaceae family, including sage, thyme, and basil, has long been recognized as a rich source of diverse and unique anthocyanins. Because purple basil varieties have become more popular in the ornamental and herb trade, we conducted a study to identify and characterize the anthocyanins present in eight varieties of purple basils (Ocimum basilicum) utilizing high-pressure liquid chromatography, spectral data and plasma-desorption mass spectronomy. Nine different anthocyanins were identified. Seven of the pigments were cyanidin-based, with cyanidin-3-(6”-p-coumarylglucoside)-5-(6”'-malonylglucoside) as the major pigment. Two minor pigments based on peonidin were also identified. Total anthocyanin content was also determined and comparisons made to other anthocyanin sources.