ABSTRACT
Fragrances of many flower families have been sampled and the volatiles analyzed. Knowing the compounds that make up the fragrances can be an important step to conservation of flowers that are threatened or endangered. Because floral fragrance is critical for attracting pollinators, this method could be used to better understand or even enhance pollination. We present a protocol using a portable charcoal air filter and vacuum to collect floral fragrance volatiles, which are then analyzed by a GC-MS. By using this method, fragrance volatiles can be sampled using a non-destructive method with a machine that is easily transported. This methodology uses a rapid sampling procedure, cutting sampling time down from 2-3 hours to approximately 10 minutes. Using GC-MS, the fragrance compounds can be identified individually, based on authentic standards. The steps used for collecting fragrance and control data are presented, from material setup to collecting the data output.
Subject(s)
Flowers/chemistry , Gas Chromatography-Mass Spectrometry/methods , Volatile Organic Compounds/chemistryABSTRACT
South Florida is home to a number of native species of orchids. The Florida Panther National Wildlife Refuge has 27 known species, including Prosthechea cochleata, the clamshell orchid, which is listed as endangered on Florida's Regulated Plant Index. In a prior study done on this species in Mexico, P. cochleata was found to produce no floral fragrance at the particular study location. However, blooming orchids of this species at the University of Florida in Gainesville, were noted to be fragrant. In this paper, we document the presence of floral fragrance compounds from P. cochleata by using by gas chromatography mass spectrometry (GC/MS) analysis of headspace volatile collection. The orchids sampled were found to be consistently producing eight volatiles that are common in floral fragrances, including those of previous orchid species studied. By knowing the fragrance compounds produced, we can better understand the pollination biology of this endangered orchid. This information could be used to help future conservation efforts for P. cochelata by increasing pollination and subsequent seed capsule production.
Subject(s)
Endangered Species , Flowers/physiology , Odorants/analysis , Orchidaceae/physiology , FloridaABSTRACT
The cheyletid predator Hemicheyletia wellsina was found in association with orchid pests in a Florida greenhouse. The life history of H. wellsina was determined using the two-spotted spider mite, Tetranychus urticae, as prey in the laboratory. Hemicheyletia wellsina is arrhenotokous, with mated females producing a female-biased sex ratio of 3.4:1. Adult longevity averaged 30.2 days, with females producing an average of 18.5 eggs. Adult females live up to 17 days without food, surviving an average of 9.7 days. Hemicheyletia wellsina will readily feed on the phytoseiid Metaseiulus occidentalis, suggesting intraguild predation by H. wellsina on phytoseiids could be important in pest management programs. The average prey consumption of H. wellsina is 1.5 T. urticae females per day. The results of this study provide information on an under-studied group of mite predators. Although H. wellsina does not have the qualities that would be necessary for its use in an augmentative or classical biological control program, its use in naturally occurring biological control could be beneficial.
