We report the analysis of floral fragrance volatiles from two scented amaryllis species, Hippeastrum brasilianum and Hippeastrum parodii. Whereas the headspace of H. brasilianum is dominated by a large peak of (Z)-β-ocimene (88% of total peak area), H. parodii has two large peaks comprising 78%, identified as eucalyptol (1,8-cineole, 30%) and (Z)-β-ocimene (48%). The two species also differ in other constituent compounds. Overall, H. parodii, although producing less total volatile organic compounds (VOCs), has a more diverse bouquet. This species also exhibits an inverse pattern of emission between eucalyptol and β-ocimene, both daily and across the 4-day period from anthesis to senescence of the flower. We compare our results with reports for a complex amaryllis hybrid and a bat-pollinated species, Hippeastrum calyptratum. The hybrid had a very different complement of emissions. The bat-pollinated species shared some of the same constituent volatiles as H. brasilianum and H. parodii, but at lower percentages, and emitted a more diverse assortment of compounds. We conclude that both H. brasilianum and H. parodii attract lepidopteran pollinators but suggest that H. parodii may also attract other insects. We briefly discuss floral fragrance from the perspective of breeding amaryllis.
Okra (Abelmoschus esculentus ‘Clemson Spineless’) was grown on an Orangeburg sandy loam soil in Shorter, AL. Okra was direct-seeded in single rows. Treatments consisted of five mulch colors: black, white, red, silver, and blue installed either with or without spun-bonded row cover. Soil temperatures were 4 to 7 °C lower than air temperatures in all treatments. The use of darker (black, blue, red) -colored plastic mulches increased early and total yield of okra compared with bare soil with and without row cover. Increased soil and air temperatures did not always correlate to an increase in yield. It can be concluded that the use of dark plastic mulch is advantageous to growers of okra in climates that do not have cool springs, but the added use of row covers to plastic mulch has no effect on growth and yield. The profit of marketable okra produced using a row cover was $1.37 versus $1.35 per pound without a cover in 2003 and $1.28 versus $1.29 per pound in 2004. Blue plastic mulch is ≈$0.08 per foot more expensive than black plastic. Our data do not show an economic advantage for blue over black mulch for okra, but the positive effect cited by other authors may be more pronounced with leafy vegetables.