An efficient method for a numerical description of virgin olive oil color with only two absorbance measurements

Four polynomial expressions are obtained that provide a good approximation and an easy, rapid calculation of the chromatic coordinates and the chroma—L ^*, a ^*, b ^*, and C—for the illuminant C and the standard observer, for a virgin or extra virgin olive oil; absorbance is measured at only 480 and 670 nm. These are as follows: L ^*=0.556458(A₄₈₀)²−2.51145A₄₈₀+0.55504(A₆₇₀)²−8.53016A₆₇₀+98.4089; a ^*=0.177372(A₄₈₀)²+2.1363A₄₈₀+1.43254(A₆₇₀)²−0.789231A₆₇₀−13.9246; b ^*=−16.0277(A₄₈₀)²+79.8932A₄₈₀−5.06558(A₆₇₀)²+3.36169A₆₇₀+31.9405; C=−15.8439(A₄₈₀)²+78.9312A₄₈₀−5.26784(A₆₇₀)²+3.56917A₆₇₀+33.3927. These give acceptable results, making the method a practical alternative to the extremely laborious Commission Internationale d’Eclairage (CIE) L ^* a ^* b ^* system, by which 391 absorbance values must be measured individually, nanometer by nanometer, before applying more complex equations. The validity of the proposed method has been confirmed by comparison, using a set of 20 sample oils different from the set of 25 oils used to generate the order of the equations. The variations between the values provided by the proposed and standard methods, respectively, had a mean of 0.00 for each of the chromatic variables—L ^* , a ^* , b ^* , and C; SD were moderate (0.71, 0.52, 1.22, and 1.22, respectively); the root mean square and the R ²-terms also confirmed the validity of the method.     

(6Z,9Z-3R,4S)-Epoxy-heptadecadiene: major sex pheromone component of the larch looper,Semiothisa sexmaculata (Packard) (Lepidoptera: Geometridae)

Gas chromatographic-electroantennographic analysis (GC-EAD) of female larch looper,Semiothisa sexmaculata (Packard), gland extracts revealed two EAD-active compounds. Retention index calculations, GC-mass spectroscopy in selected ion monitoring mode, and GC-EAD analysis of authentic standards identified the compounds as (3Z,6Z,9Z)-heptadecatriene (3Z,6Z,9Z-17H) and (6Z,9Z)-cis-3,4-epoxy-heptadecadiene (6Z,9Z-cis-3,4-epoxy-17H). Chirality determination of the monoepoxydiene in gland extracts was impeded by small quantities, but field experiments indicated that maleS. sexmaculata were most strongly attracted to enantiomerically enriched 6Z,9Z-3R,4S-epoxy-17H (69% ee), while maleS. neptaria (Guenée) responded well to various blends of theR,S- and S,R-epoxide enantiomers. Binary combinations of theR,S-epoxide enantiomer with 3Z,6Z,9Z-17H significantly inhibited response by maleS. sexmaculata, but strongly enhanced attraction of sympatric maleS. marmorata Ferguson. Enantiomerically enriched 6Z,9Z-3R,4S-epoxy-17H can be used as a trap bait to monitor populations of the larch-defoliatingS. sexmaculata. Whether 6Z,9Z-3R,4S-epoxy-17H serves as single component sex pheromone inS. sexmaculata or small amounts of 6Z,9Z-3S,4R-epoxy-17H synergize or suppress optimal attraction, will be tested as chirally pure monoepoxydienes become available.     

(7<Emphasis Type="Italic">Z</Emphasis>,9<Emphasis Type="Italic">E</Emphasis>)-2-Methyl-7,9-Octadecadiene: A Sex Pheromone Component of <Emphasis Type="Italic">Lymantria Bantaizana</Emphasis>

Our objective was to identify the sex pheromone of Lymantria bantaizana (Lepidoptera: Lymantriidae) whose larvae feed exclusively on walnut, Juglans spp., in China, and Japan. Coupled gas chromatographic–electroantennographic detection (GC-EAD) analyses of pheromone gland extracts revealed a single EAD-active component. Retention index calculations of this compound on four GC columns suggested that it was a methyl-branched octadecadiene with conjugated double bonds. In GC-EAD analyses of 2-methyloctadecenes, (Z)-2-methyl-7-octadecene and (E)-2-methyl-7-octadecene elicited the strongest antennal responses, suggesting that the double bond positions were at C7 and C9. In comparative GC-EAD analyses of pheromone gland extract and stereoselectively synthesized isomers (E,E; E,Z; Z,E; Z,Z) of 2-methyl-7,9-octadecadiene, the (E,Z)- and (Z,E)-isomer had retention times identical to that of the candidate pheromone, but only the latter isomer elicited strong EAD activity. Results of field experiments in Japan substantiated that (7Z,9E)-2-methyl-7,9-octadecadiene is the L. bantaizana sex pheromone, a compound previously unknown in the Lepidoptera. Detection surveys in North America for exotic Eurasian forest defoliators could include traps baited with the L. bantaizana pheromone.     

Sex phermone components of mulberry looper,Hemerophila atrilineata butler (lepidoptera: Geometridae)

(6Z-9S, 10R)-Epoxy-octadecene (SR-1) and (3Z, 6Z-9S, 10R)-epoxy-octadecadiene (SR-2) are sex pheromone components of the mulberry looper (MBL),Hemerophila atrilineata Butler. Compounds extracted from female MBL pheromone glands were identified by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometry. In field experiments in China,SR-2,RS-2, or both combined were hardly attractive, butSR-2 in combination withSR-1 attracted significant numbers of MBL males. Synergistic behavioral activity ofSR-1 plusSR-2, but not of corresponding antipode mixtures, indicates enantiospecificity of MBL pheromone communication. Because blends of racemic and enantiospecific (SR)1 plus2 were similarly attractive, racemic1 plus2 may have potential for mass trapping or confusion of MBL males in commercial mulberry plantations.     

Effect of Volatile Constituents from <Emphasis Type="Italic">Securidaca</Emphasis><Emphasis Type="Italic">Longepedunculata</Emphasis> on Insect pests Of Stored Grain

Securidaca longepedunculata Fers (Polygalaceae) is commonly used as a traditional medicine in many parts of Africa as well as against a number of invertebrate pests, including insects infesting stored grain. The present study showed that S. longepedunculata root powder, its methanol extract, and the main volatile component, methyl salicylate, exhibit repellent and toxic properties to Sitophilus zeamais adults. Adult S. zeamais that were given a choice between untreated maize and maize treated with root powder, extract, or synthetic methyl salicylate in a four-way choice olfactometer significantly preferred the control maize. Methyl salicylate vapor also had a dose-dependant fumigant effect against S. zeamais, Rhyzopertha dominica, and Prostephanus truncates, with a LD₁₀₀ achieved with a 60 l dose in a 1-l container against all three insect species after 24 hr of exposure. Probit analyses estimated LD₅₀ values between 34 and 36 l (95% CI) for all insect species. Furthermore, prolonged exposure for 6 days showed that lower amounts (30 l) of methyl salicylate vapor were able to induce 100% adult mortality of the three insect species. The implications are discussed in the context of improving stored product pest control by small-scale subsistence farmers in Africa.     

(3Z,6Z,9Z)-Nonadecatriene and enantiomers of (3Z,9Z)-cis-6,7-Epoxy-nonadecadiene as sex attractants for two geometrid and one noctuid moth species

Sex attractants for the geometrid mothsEufidonia convergaria andCaripeta angustiorata, and the noctuid mothRivula propinqualis have been elucidated during field screening of a series of (3Z,6Z,9Z)-triene hydrocarbons (C_17–22), and the racemic and enantiomerically enriched monoepoxydienes derived from those hydrocarbons. Biologically active compounds were identified by a combination of field testing of synthetic standards, electroantennography, and coupled gas chromatography-electroantennogram detection.E. convergaria males were optimally attracted by a 11 blend of (3Z,9Z)-(6S,7R)-epoxy-nonadecadiene (3Z,9Z-6S,7R-epoxy-19H); other abbreviations follow the same system) with (3Z,6Z,9Z)-nonadecatriene (3Z,6Z,9Z-19H). The 6R,7S enantiomer of the epoxide had no apparent biological activity, either as an attractant or as a behavioral antagonist. Male moths also were attracted to blends of the C₁₈ and C₂₀ homologs of the triene and the epoxide. 3Z,6Z,9Z-19H and 3Z,6Z-cis-6,7-epoxy-19H were identified inE. convergaria female pheromone gland extracts. Males of the geometrid moth speciesC. angustiorata were attracted by a 11 blend of 3Z,6Z,9Z-19H and enantiomerically enriched 3Z,9Z-6R,7S-epoxy-19H. Males of the noctuid mothR. propinqualis were attracted by an approximately 101 blend of 3Z,6Z,9Z-19H and enantiomerically enriched 3Z,9Z-6S, 7R-epoxy-19H. The components were synergistic, with neither being attractive alone. The blend ratio was quite specific, as the attractiveness of blends decreased sharply on either side of the optimum ratio.Issued as NRC No. 30266.     

Sex Pheromone of Nuttall's Sheep Moth, Hemileuca nuttalli, from the Eastern Sierra Nevada Mountains of California

The sex attractant pheromone blend of Hemileuca nuttalli (Lepidoptera: Saturniidae) from the eastern slope of the Sierra Nevada Mountains in California was determined to be a combination of E10,Z12-hexadeca-10,12-dien-1-yl acetate (E10,Z12–16:Ac) and E10,E12-hexadeca-10,12-dien-1-yl acetate (E10,E12–16:Ac). Ratios of the compounds in extracts of female pheromone glands varied around a mean of 100:48, although the ratio was not critical in field trials. Blends of synthetic E10,Z12–16:Ac and E10,E12–16:Ac in 100:50, 50:100, and 100:100 ratios attracted equal numbers of male moths. Field trials also indicated that E10,Z12–hexadeca-10,12-dien-1-ol (E10,Z12–16:OH) and E10,Z12-hexadeca-10,12-dienal (E10,Z12–16:Ald) were antagonistic at rates of 3.3% and 10%, respectively, of the E10,Z12–16:Ac, despite being found in female moth extracts. E10,E12–16:Ac, E10,Z12–16:OH, and E10,Z12–16:Ald all appear to have roles in maintenance of reproductive isolation between H. nuttalli and H. eglanterina.     

Enantiospecific antennal response of bark beetles to spiroacetal (E)-conophthorin

Optically pure synthetic enantiomers of (E)-conophthorin [(E)-7-methyl-1,6-dioxaspiro[4.5]decane], one of the volatiles affecting coniferophagous bark beetles, were tested on antennae of Ips typographus, I. duplicatus, I. subelongatus, Dendroctonus micans, and five Scolytus spp. by using combined gas chromatography–electroantennographic detection (GC-EAD). EAD dose–responses indicated that all three Ips species perceived only the naturally occurring and quantitatively dominant (5S,7S)-enantiomer, while its antipode, (5R,7R)-(E)-conophthorin was antennally inactive. Response thresholds for the Ips species were estimated as between 0.1 ng and 1 ng, or lower. The antennal responses of the Ips species caused by 100 ng of the (5R,7R)-enantiomer might be due to 1% impurity-(the active (5S,7S)-enantiomer) in the (5R,7R)-sample. At the 50-ng level, D. micans and five angiosperm Scolytus species (S. intracatus, S. mali, S. ratzeburgi, S. rugulosus, and S. scolytus) responded strongly to the (5S,7S)-enantiomer, while the (5R,7R)-enantiomer was antennally inactive. Currently updated knowledge on the natural occurrence, and electrophysiological and behavioral activity of (E)-conophthorin is summarized.     

Sex attractants for Geometrid and Noctuid moths

Male moths belonging to 17 species of Geometridae and nine species of Noctuidae were captured in traps baited with synthetic chemicals as part of a field screening program. The compounds tested were the C₁₈-C₂₂ homologs of: (1) (3Z,6Z,9Z)-triene hydrocarbons; (2) mixtures containing equal quantities of (3Z,6Z)-cis-9,10-expoxydienes, (3Z,92Z)-cis-6,7-epoxydienes, and (6Z,9Z)-cis-3,4-epoxydienes; (3) (3Z,6Z)-9S,10R-epoxydienes; (4) (3Z,6Z)-9R,10S-epoxydienes; and (5) (3Z,6Z,9Z,11E)-nonadecatetraene. Field captures and electroantennographic assays revealed a high degree of specificity in the responses of many species to the synthetic chemicals. In several species the ability of males to discriminate between the 9S,10R and 9R,10S enantiomers of the monoepoxydiene isomers was clearly shown. Synergists and inhibitors were discovered for several of the reported attractants, some of which were not previously known to have semiochemical activity. The geometrid moths captured includedEpirrhoe sperryi (Herbulot),Mesoleuca ruficillata (Guenée),Triphosa haesitata (Guenée),Metanema inatomaria (Guenée),Prochoerodes transversata (Drury),Cabera erythemaria (Guenée),Synaxis jubararia (Hulst),Dysstroma brunneata ethela (Hulst),Eulithes testata (Linnaeus),Sicya macularia (Harris),Xanthorhoe iduata (Guenée),X. abrasaria aquilonaria (Herrich-Schäffer),X. munitata (Hübner),Itame loricaria (Eversmann),Eupithecia annulata (Hulst),E. rovocastaliata (Packard) andE. satyrata dodata (Taylor). The noctuid moths captured includedBleptina caradrinalis (Guenée),Idia américalis (Guenée),I. aemula (Hübner),Rivula propinqualis (Guenée),Lomanaltes eductalis (Walker),Spargaloma sexpunctata (Grote),Caenurgina distincta (Neumuller),Euclidia cuspidea (Hübner), andZale duplicata (Bethune). Six of the nine noctuid species captured belong to three subfamilies for which sex attractants had not been reported previously. Details for the stereospecific synthesis of (3Z,6Z)-cis-9,10-epoxydienes are also reported.Issued as NRCC No. 24314.     

Sex Attractant Pheromone of Saturniid Moth Coloradia velda

The female-produced sex attractant pheromone of Coloradia velda has been identified by a combination of analytical methods and field tests as a blend of (10E,12Z)-hexadecadien-1-yl acetate (10E,12Z–16:Ac), (10E,12E)-hexadecadien-1-yl acetate (10E,12E–16:Ac), and (10E,12Z)-hexadecadien-1-ol (10E,12Z–16:OH) in a 10:1:0.33 ratio, respectively. The corresponding aldehyde (10E,12Z–16:Ald) was also found in extracts of female pheromone glands, but in blends with 10E,12Z–16:Ac and 10E,12E–16:Ac at low doses did not significantly increase the attractiveness of baits to male moths.     

Enantiomers of (Z,Z)-6,9-Heneicosadien-11-OL: Sex Pheromone Components of Orgyia detrita

(6Z,9Z,11S)-6,9-Heneicosadien-11-ol (Z6Z9-11S-ol-C21) and (6Z,9Z,11R)-6,9-heneicosadien-11-ol (Z6Z9-11R-ol-C21) were identified as major sex pheromone components of female tussock moths, Orgyia detritaGuérin-Méneville (Lepidoptera: Lymantriidae), on the basis of (1) analyses of pheromone gland extracts of female O. detrita by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC mass spectrometry, and (2) field trapping experiments with synthetic standards. Z6Z9-11S-ol-C21 and Z6Z9-11R-ol-C21 in combination, but not singly, attracted significant numbers of male moths. Racemic Z6Z9-11-ol-C21 was more attractive than the 1:3.5 (R:S) blend ratio found in pheromone gland extracts from female moths. Lower and higher homologues of Z6Z9-11-ol-C21 were also detected in GC-EAD recordings of pheromone extracts, and the racemic compounds enhanced attractiveness of Z6Z9-11-ol-C21 in field experiments. Because of trace amounts of these homologues in extracts, their enantiomeric composition could not be determined. This is the first report of secondary alcohols as pheromone components in the ditrysian (advanced) Lepidoptera.     

Identification of Female Sex Pheromone of the Rice Leaf Bug, Trigonotylus caelestialium

The female sex pheromone of the rice leaf bug, Trigonotylus caelestialium, was analyzed by GC-EAD and GC-MS. Ten EAD active compounds—n-hexyl n-hexanoate, (E)-2-hexenyl n-hexanoate, n-hexyl (E)-2-hexenoate, n-octyl n-butyrate, n-octyl n-hexanoate, (E)-2-octenyl n-hexanoate, n-pentyl n-hexanoate, n-hexyl n-butyrate, (E)-2-hexenyl n-butyrate, and n-hexyl (E)-2-butenoate—were detected in the ratio of 1000:414–491:trace–5:5–11:55–71:50–63:trace–3:225:90:32 from female body extracts, and in the ratio of 1000:271–342:10–43:1–3:58–78:14–19:trace:178:36:26 from male body extracts. Field trapping tests with these synthetic compounds indicated that n-hexyl n-hexanoate, (E)-2-hexenyl n-hexanoate, and n-octyl n-butyrate are pheromone components, and mixtures in ratios of 1000:400–500:10–100 were more attractive to males. Doses ranging from 4.29 g to 14.3 g of the three-component mixture in the ratio of 1000:400:30 loaded into glass capillary tubes were most attractive to males.     

Species discrimination in five species of winter-flying geometrids (Lepidoptera) based on chirality of semiochemicals and flight season

Enantiomer separation of (6Z,9Z)-cis-3,4-epoxynonadecadiene and (3Z,9Z)-cis-6,7-epoxynonadecadiene could be achieved using chiral high-resolution gas chromatography and a cyclodextrin-bond column. (3Z,9Z)-(6R,7S)-Epoxynonadecadiene was identified from ovipositor extracts ofColotois pen-Naria, while inErannis defoliaria the 6S,7R-enantiomer was found. In field trapping tests pure synthetic enantiomers caught only conspecific males of these species. (3Z,6Z,9Z)-Nonadecatriene was found in both species, while the presence of (3Z,6Z,9Z)-heneicosatriene was indicated inC. Pennaria only. A 10103 blend of (3Z,9Z)-(6R,7S)-epoxynonadecadiene, (3Z,6Z,9Z)-heneicosatriene, and (3Z,6Z,9Z)-nonadecatriene was found to be optimal for catchingC. Pennaria, whileE. Defoliaria males were optimally caught by a 11 mixture of (3Z,9Z)-(6S,7R)-epoxynonadecadiene and (3Z,6Z,9Z)-nona-decatriene. (6Z,9Z)-(3S,4R)-Epoxynonadecadiene was identified from ovipositor extracts ofAgriopis (Erannis) aurantiaria. In field tests the pure enantiomer proved to be a highly specific sex attractant for both the late autumn/early winter flyingA. Aurantiaria and the late winter/early spring flyingA. Leucophearia. Males ofAgriopis marginaria, which fly in late winter/early spring, were attracted to (3Z,9Z)-(6S,7R)-epoxynonadecadiene. The addition of (3Z,6Z,9Z)-nonadecatriene to theS,R-enantiomer increased captures. Optimal catches were recorded with a 103 epoxide-hydrocarbon blend. Enantiomer specificity in all species was confirmed in EAG measurements.     

(3Z,6Z,9Z, 12Z, 15Z)-Pentacosapentaene, a key pheromone component of the fir coneworm moth, Dioryctria abietivorella

The sex pheromone of the fir coneworm moth consists of a blend of (3Z,6Z,9Z,12Z,15Z)-pentacosapentaene and (9Z,11E)-tetradecadienyl acetate. Analogous blends of polyunsaturated, long-chain hydrocarbons with much shorter chain aldehydes or alcohols recently have been discovered in three other moth species in the superfamily Pyraloidea. These combinations of components from two distinct structural classes may represent an important and widespread new pheromone blend motif within the Lepidoptera.     

Sex Pheromone of the Saturniid Moth, <Emphasis Type="Italic">Hemileuca burnsi</Emphasis>, from the Western Mojave Desert of California

The sex pheromone blend of Hemileuca burnsi (Lepidoptera: Saturniidae) from the western Mojave Desert was determined to be a combination of (10E,12Z)-hexadecadien-1-yl acetate (E10,Z12-16:Ac), (10E,12Z)-hexadecadien-1-ol (E10,Z12-16:OH), (10E,12E)-hexadecadien-1-yl acetate (E10,E12-16:Ac), and hexadecyl acetate (16:Ac). (10E,12Z)-Hexadecadienal (E10,Z12-16:Ald) was tentatively identified in pheromone gland extracts based on electroantennographic responses and, when added to the above blend, it enhanced trap captures at low doses. The mean ratio of the compounds in extracts of pheromone glands was 100:23:232:14:0.4 (E10,Z12-16:Ac: E10,E12-16:Ac: 16:Ac: E10,Z12-16:OH: E10,Z12-16:Ald). Field trials indicated that although E10,Z12-16:Ac and E10,Z12-16:OH were essential for attraction, the two-component blend was not attractive by itself. Addition of the three other compounds was necessary for maximum attraction, rendering this the most complicated pheromone blend described for a Hemileuca species to date. Similarities between the sex pheromone of H. burnsi and that of the allopatric Hemileuca electra electra and differences between the blends of H. burnsi and that of the sympatric H. electra mojavensis support a case for reproductive character displacement in the pheromone communication channel of H. electra.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Sex pheromone components of the buck moth Hemileuca maia

The sex attractant pheromone blend of Hemileuca maia (Lepidoptera: Saturniidae) from the vicinity of Baton Rouge, Louisiana, has been identified. The major component of the blend is (E10,Z12)-hexadeca-10,12-dienal (E10,Z12–16:Ald), in combination with the minor components (E10,Z12)-hexadeca-10,12-dien-1-ol (E10,Z12–16:OH), and (E10,Z12)-hexadeca-10,12-dien-1-yl acetate (E10,Z12–16:Ac). Ratios of the compounds in extracts of female pheromone glands varied around a mean of 100:7.4:6.3. None of the three components were attractive to male moths when tested as single components. Several other compounds were tentatively identified from female pheromone gland extracts, including E10,E12–16:Ald, E10,E12–16:OH, and E10,E12–16:Ac, but addition of these components, either alone or in combination, at biologically relevant rates, did not significantly increase the attractiveness of lures. The saturated analogs, hexadecanal, hexadecanol, and hexadecyl acetate, also were identified in gland extracts, but had no apparent effect as pheromone components.     

Chemical defense secretions of some species of Malaysian rhinotermitidae (Isoptera,Rhinotermitidae)

The defense secretions of the soldiers of the Malaysian rhinotermitid,Parrhinotermes aequalis (Havilandi) andP. pygmaeus (John),Termitogeton planus (Havilandi) andSchedorhinotermes malaccensis (Holmgren) consist mainly of vinyl ketones, whereas that ofProrhinotermes flavus (Bugnion & Popoff) gives (E)-1-nitropentadecene. The chemistry of the defense secretions ofParrhinotermes andTermitogeton is documented and based on their chemical relationships;Termitogeton shows a closer affinity to the Rhinotermitinae than Heterotermitinae.     

Rhizopus and Fusarium are Selected as Dominant Fungal Genera in Rhizospheres of Brassicaceae

We isolated several strains of Rhizopus and Fusarium spp. as dominant fungi in the rhizospheres of Brassicaceae plants. The Fusarium isolates showed a higher tolerance of the antifungal constituents of "mustard oil," which originates from the glucosinolates that are characteristic secondary metabolites of the Brassicaceae, than other Fusarium isolates from non-Brassicaceae plants. In contrast, the Rhizopus isolates showed a high tolerance regardless of their source. Myrosinase activity was found in Bn-R-1-1 (Rhizopus sp.) isolated from the rhizoplane of Brassica napus and Ls-F-in-4-1 (Fusarium sp.) isolated from a surface-disinfected root of Lepidium sativum (Brassicaceae). Ls-F-in-4-1 was the Fusarium most tolerant of the Brassicaceae antifungal constituents. These results suggest that fungi in the rhizospheres of Brassicaceae plants may be selected because of secondary metabolites exuded from the roots of host plants.     

Optical isomers of 3,13-dimethylheptadecane: Sex pheromone components of the western false hemlock looper,Nepytia freemani (Lepidoptera: Geometridae)

(3S, 13R)-3, 13-Dimethylheptadecane [(3S, 13R)-3, 13-dime-17Hy] is the major pheromone component of the western false hemlock looper (WFHL),Nepytia freemani. In comparative gas chromotographic-electroantennographic detection (GC-EAD) analyses of stereoselectively synthesized isomers, 1 pg of (3S, 13R)-dime-17Hy elicited significantly stronger electrophysiological responses by male WFHL antennae than did 1 pg of separately injected (3R, 13R)-, (3R, 13S)- or (3S, 13S)-3, 13-dime-17Hy. In field experiments with individually tested stereoisomers. (3S, 13R)-3, 13-dime-17Hy was the only stereoisomer to attract males, but the four-stereoisomer blend was 3.6 times more attractive. Quaternary and all binary combinations of (3S, 13R)-3, 13-dime-17Hy with the other stereoisomers were equally attractive, suggesting that synergisytic behavioral activity in WFHL resided with either one of (3R, 13R)-, (3R, 13S)-, or (3S, 13S)-3, 13-dime-17Hy. Because optical isomers of (di)methylhydrocarbons do not separate on currently available columns, it remains unknown whether female WFHL also produce a four-stereoisomer pheromone blend. Substitutionality of pheromone stereoisomers without loss of behavioural activity has not previously been reported, but favorably compares with the concept of pheromone redundancy that was first suggested for the multiple pheromone component blend of the cabbage looper moth,Trichoplusia ni.