Plant volatiles

The isomers of 1,3,5-undecatriene ia living plant volatiles are partly responsible for the unique, fresh natural-green character of the living herb. 

For high-pressure plant, volatile reagents are preferred even for storage in case any chemical is inadvertently left in during subsequent operation. As with on-load protection, ammonia and hydrazine are used. With ammonia alone, a pH value of greater than about 10-5 is desirable, whilst with ammonia and hydrazine together, about 50 mg/kg of each, giving a pH value of about 10-0, is adequate. 

Pichersky E. and J. Gershenzon (2002). The formation and function of plant volatiles Perfumes for pollinator attraction and defense. Curr. Opin. Plant Biol. 53 237-243. 

Carroll M. J. and Berenbaum M. R. (2002). Behavioral responses of the parsnip webworm to host plant volatiles. J Chem Ecol 28 2191-2201. 

Unlike parasitoids of other insect orders that have host-seeking larvae, most parasitic hymenoptera lay their eggs on, in, or very close to a host individual [11]. This requires the adult female to find a suitable host, often with the aid of chemical cues from host frass, pheromones, plant volatiles emitted upon host feeding or egg-deposition, silk, honeydew and other secretions. She may then chemically mark the host following oviposition to reduce superparasitism by herself or intra- and inter-specific insects [11]. 

Tetratrophic interactions between a host plant, a phytophagous pest (primary host), a hymenopteran parasitoid or symbiont (secondary host) and a hymenopteran hyperparasitoid (which parasitizes the secondary host) are of considerable importance, because hyperparasitism can significantly reduce populations of economically beneficial parasitoids [11]. Hyperparasitoids use host-marking (=spacing) pheromones, sex pheromones [12], and host-detection cues [42], but they also show additional chemically mediated interactions with the other partners. These include detection of the primary host s secretions by the hyperparasitoid [43], detection of plant volatiles by the hyperparasitoid [44], and detection of the hyperparasitoid s secretions by the primary host [45] or by the secondary host. The latter causes the secondary host to avoid locations where the hyperparasitoid is foraging [46]. 

An example of a larval parasitoid that responds to the host sex pheromone is seen with Cotesiaplutellae (Braconidae), also a parasitoid of the diamondback moth. These insects were attracted equally to the pheromone blend (31,32,33, see above), the acetate 32, or aldehyde 31 components [80]. This larval parasitoid, however, was also strongly attracted to host frass volatiles, in particular, dipropyl disulfide 34, dimethyl disulfide 35, allyl isothiocyanate 36, and dimethyl trisulfide 37. In contrast, the egg parasitoid Trichogramma chilonis was only weakly attracted to 36. In both, T. chilonis and C. plutellae, plant volatiles, in particular (3Z)-hex-3-en-l-yl acetate 38, significantly enhanced attraction by the pheromone [80]. 

CHALCIDOIDEA Aphelinidae Encarsiaformosa Trialeurodes vaporariorum Damaged plant volatiles [attractant] (3Z)-Hex-3-en-l-ol 39 octan-3-one 51 [84]... 

PARE, P.W., TUMLINSON, J.H., Plant volatiles as a defense against insect herbivores, Plant Physiol., 1999,121, 325-332. 

Arimura G, Matsui K, Takabayashi J (2009) Chemical and molecular ecology of herbivore-induced plant volatiles proximate factors and their ultimate functions. Plant Cell Physiol 50 911-923... 

Dudareva N, Negre F, Nagegowda DA, Orlova I (2006) Plant volatiles recent advances and future perspectives. Crit Rev Plant Sci 25 417-440... 

Dicke M, van Loon J (2000) Multitrophic effects of herbivore-induced plant volatiles in an evolutionary context. Entomol Exp Appl 97 237-249... 

The transport processes that may move disulfoton from soil to other media are volatilization, leaching, runoff, and absorption by plants. Volatilization of disulfoton from wet soil may be greater than from relatively dry soil (Gohre and Miller 1986). Like other pesticides, disulfoton in soil partitions between soil-sorbed and soil-water phases (Racke 1992). This latter phase may be responsible for the volatilization of disulfoton from soil however, due to the low Henry s law constant value, the rate of disulfoton volatilization from the soil-water phase to the atmosphere would be low. 

Leal WS (2003) In Bomquist GJ, Vogt RG (eds) Insect pheromone biochemistry and molecular biology, the biosynthesis and detection of pheromones and plant volatiles. Elsevier Academic Press, London, p 447... 

The biological activity of the banana weevil pheromone and those of related palm weevil species is strongly enhanced by host plant volatiles [399,417-419]. 

Herbivore-Induced Plant Volatiles (HIPVs) (e.g. homoterpenes, DMNT and TMTT)... 

Fig. 11.1 Simplified scheme of the emission and function of herbivore-induced plant volatiles in plant defense. DMNT, 4,8-dimethyl-l,3,7-nonatriene) TMTT, 4,8,12-trimethyltrideca-l,3,7, 11-tetraene...

Pichersky E, Noel JP, Dudareva N (2006) Biosynthesis of plant volatiles nature s diversity and ingenuity. Science 311 808-811... 

Goff SA, Klee HJ (2006) Plant volatile compounds sensory cues for health and nutritional value. Science 311 815-819... 

Kessler A, Baldwin IT (2001) Defensive function of herbivore-induced plant volatile emissions in nature. Science 291 2141-2144... 

Boland W, Feng Z, Donath J, Gabler A (1992) Are acyclic C-11 and C-16 homoterpenes plant volatiles indicating herbivory. Naturwissenschaften 79 368-371... 

Dudareva N, Pichersky E (2008) Metabolic engineering of plant volatiles. Curr Opin Biotechnol 19 181-189... 

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