Field Bioassay

The pheromone chemistry of A. hilare has been studied in detail, using both laboratory (vertical Y-tube) and field bioassays [75]. In Y-tube bioassays, mature females were attracted by male odors, but males were not attractive to other males, and females were not attractive to either sex. Males produced (-)-cis-Z-BAE and (-)-frazzs-Z-BAE in a -19 1 ratio, and other compounds in the extracts were not active. The 19 1 blend was more attractive to females than other ratios, and the individual components were not attractive, indicating that both compounds were required. Females were attracted to the synthetic blend in field cage trials [75],but as with most other phytophagous pentatomids,few bugs were caught in pheromone-baited traps (J.G. Millar and H.M. McBrien, unpublished data). 

Almost simultaneously with the identification of 2E, 4 , 6Z- 10 COOMe, a thermally unstable stereoisomer, 2E, 4Z, 6Z- 10 COOMe 118, was found to be a key component of the male-produced sex pheromone of Thyanta pallidovirens> along with the sesquiterpenes (+)-a-curcumene, (-)-P-sesquiphellandrene, and (-)-zingiberene 119 [10,25]. 2E, 4Z, 6Z-10 COOMe was an essential component of the attractive blend, whereas any one, any two, or all three of the sesquiterpene components were equally effective as the other portion of the blend. None of the components were active alone. Pheromone blends attracted only females in both laboratory and field bioassays [10]. The same compounds are also produced by the congener T. custator [10] and other Thyanta spp. (J.G. Millar, unpublished data). 

American Society for Testing and Materials (ASTM) 2001, Standard Guide for Conducting In-situ Field Bioassays widi Marine, Estuarine, and Freshwater Bivalves. Annual Book of ASTM Standards No. E 2122-01 Vol 11.05 Philadelphia, PA pp. 1562—1591. 

The synthesis of pheromones remains an important cornerstone of pheromone research and development. The initial synthesis of an insect pheromone serves not only to confirm the structural identification, but also provides authentic material for either laboratory or field bioassay. Oftentimes, larger quantities of the pheromones are desired for the development of monitoring and pest control methods. The scale up of the synthesis of complex pheromone compounds is often a major bottleneck in the practical application of pheromones. Also, the unusual structure of some pheromone compounds beckons synthetic chemists to apply new methodology in order to show off their methods. 

Field bioassays with adult cerambycid beedes, Neoclytus acuminatus acumi-natus (F.) (Coleoptera Cerambycidae), revealed that males produce a pheromone that attracts both sexes. Male extracts revealed a single major male-specific compound IS, 3>S )-hexanediol. Field trials showed that a racemic blend of IS, 3S) and 2R, 3i )-hexanediols attracted both sexes and that activity was similar to enantiomerically enriched IS, 3S) hexanediol (e.e. 80.2%). However, a blend of all four stereoisomers attracted only a few beetles. ... 

The first technique using pheromones to manipulate the southern pine beetle population relies on inhibition. Field bioassays have shown that aggregation of the southern pine beetle on attractant-baited traps can be significantly reduced by the... 

Further directions for the study of both meroplankton and holoplankton chemical ecology include development of field bioassays to couple with laboratory studies. Studies are needed to determine how consumers may perceive secondary metabolites produced by plankton.166 The ability of planktonic organisms to sequester defensive chemistry in specific tissues or mucus, as seen in benthic invertebrates, is unknown. Very little is known about the specific compounds responsible for chemical defenses in plankton, and we expect the library of secondary metabolites produced... 

Kinzer G. W., Fentiman A. F., Jr, Page T. F., Jr, Foltz R. L., Vite J. P. and Pitman G. B. (1969) Bark beetle attractants identification, synthesis and field bioassay of a new compound isolated from Dendroctonus. Nature 221, 477 178. 

Ryker L. C. and Rudinsky J. A. (1982) Field bioassay of exo- and endo-brevicomin with Dendroctonus ponderosae in lodgepole pine. J. Chem. Ecol. 8, 701-707. 

Smith, R.G. (1976). Laboratory and field bioassay of the Douglas-fir tussock moth pheromone, (Z)-6-heneicosen-ll-one. Environ. Entomol., 5,1187-1190. 

It has been discovered that the crucifer flea beetle, Phyllotreta cruciferae Goeze, a significant pest of oilseed Brassica and other cruciferous crops in North America and Europe, uses a hydrocarbon pheromone. The first published evidence for a pheromone in P. cruciferae was that canola plants infested by unsexed adults were more attractive to both males and females than damaged plants only, in both laboratory and field bioassays (Peng and Weiss, 1992). Subsequently, Peng et al. (1999) determined with field bioassays that the males were the attractive sex, fitting the pattern of a male-produced aggregation pheromone. 

Zilkowski, B. W., Bartelt, R.J., Cosse, A.A. and Petroski, R.J. (2006). Male-produced aggregation pheromone compounds from the eggplant flea beetle (Epitrix fuscula) identification, synthesis, and field bioassays. J. Chem. Ecol., 32, 2543-2558. 

The San Jose scale, Quadraspidiotus perniciosus, is a serious worldwide pest of deciduous fruit trees. The pheromone has been shown to be a three-component mixture of 7-methyl-3-methylene-7-octen-l-yl propanoate (XIX), (Z)-3,7-dimethyl-2,7-octadien-l-yl propanoate (XX), and the corresponding (15)-isomer XXI (55, 56, 57) (Figure 8). Greenhouse and field bioassays have shown that XIX, XX, and XXI are independently attractive to the male San Jose scale and that the three components show almost equal attractancy (55,57). Interestingly, neryl and geranyl propanoate are inactive. 

The pure synthetic R,Z isomer was a powerful attractant for male Japanese beetles in field bioassays, whereas the 5, isomer was a strong inhibitor. As little as 1% of the j>,Z-isomer inhibited male response. 

Consideration of the environment in which a species lives and reproduces is very important, although often neglected in studying the chemical communications system of that species. In many cases it is very difficult to monitor the chemical isolation and purification with field bioassays and thus laboratory bioassays are often used. Obviously a laboratory bioassay is quite artificial in that many environmental factors that affect the insect s behavior are eliminated. In fact, bioassays conducted in the field may not measure all the behavioral components either. 

De Jong, F.M.W. (1998) Development of a field bioassay for the side effects of pesticides on decomposition. Ecotoxicology and Environmental Safety, 40, 103-114. 

Van Sickle, J., Baker, J.R, Simonin, H.A., Baldigo, B.P., Kretser, W.A. and Sharpe, W.F. (1996). Episodic acidification of small streams in the northeastern United States Fish mortality in field bioassays. Ecological Applications, 6, 408-421. Wright, R.F (2003). Predicting recovery of acidified freshwaters in Europe and Canada. Hydrology Earth System Science, 7, 429—430. 

Hott PD, Alexander TB (1959) Field bioassay of VX by means of goldfish. Tech Rep CWRL 2324 (DTIC AD 314164). U.S. Department of the Army, Chemical Warfare Laboratories, Army Chemical Center, MD. 

Table IV. Field Bioassay of Synthetic Pheromone 6 in Conjunction with Food Volatiles...

This encapsulation also protected the compounds from adverse environmental conditions in the field bioassays. Approximately 30 mg of each compound or mixture was placed in a given capillary tube using a 1-ml microsyringe with a 20-gauge needle. An empty capillary tube represented the control to complete the design of a given bioassay. 

Statistical analysis. Results of the laboratory and field bioassays were statistically evaluated by chi-square with an acceptable significance level of at least p < 0.05i... 

Abstract This chapter provides a definition of allelopathy, processes included and excluded fl om plant- tlant allelopathic interactions, criteria needed to establish plant-plant allelopathic interactions, application of the Scientific Method, use of laboratory and field bioassays, and a short paragraph on the subject matter of the rest of the book. 

Laboratory bioassays have similar problems to those of field bioassays, but on a smaller scale, i.e., they are smaller black boxes (Blum 1999, 2007). However, the physical, chemical and biological characteristics of laboratory bioassays can be more readily manipulated to hold some characteristics constant while others are being modified. The benefits of this are obvious for characterizing cause and effect relationships, but these benefits come at a cost. The cost ... 

This book describes the results/conclusions of a number of laboratory and field bioassays (i.e., experiments) each with its own set of underlying hypotheses. Because this book is a retrospective analysis it is impossible to list all the hypotheses that have been directly or indirectly tested for each reference cited. In fact, even if I wanted to it would not be possible since specific hypotheses are frequently not even stated in the plant-plant allelopathic literature. Let me suggest some reasons for that ... 

I hope that it is now clearly evident that the use of laboratory and field bioassays of residues, extracts, or individual compounds without the appropriate range of physicochemical and biotic elements (e.g., concentrations, solute potentials, pH values, nutrition, temperature, etc.) and adequate/realistic controls are no longer acceptable when attempting to identify/characterize the existence of plant-plant allelopathic interactions in nature. In spite of the difficulties a much more holistic approach is now required both in the laboratory and in the field. We need a renewed effort to develop tools and procedures that isolate and then reintegrate the actions of physicochemical and biotic elements of soil solutions, rhizospheres, and rhizoplanes that regulate/modulate allelopathic plant-plant interactions. 

Density-dependent effects in laboratory, greenhouse, and field bioassays. These, proposed almost a decade ago by Weidenhamer et al. (1987, 1989), are almost never considered. Simply put, the hypothesis states that growth reductions (phytotoxicity) observed at low plant densities will diminish as the density of the test species is increased. 

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