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Moths appearance

Only these two species of hawk moth appear to meet the dual requirements of long proboscis and properly spaced eyes and, as far as is known, only these two species pollinate the western-prairie fringed orchid. Other insects either ignore the plant as unrewarding or else fail as pollinators. The closely related eastern-prairie fringed orchid (Platanthera leucophaea) makes similarly specific demands on its pollinators, but in this case the flower transfers its pollen to the moth s proboscis. [Pg.58]

This is the first example of a reaction for which the presence of a chelating ligand was observed to facilitate rather than retard metal-catalysed epoxidation (Gao et al., 1987). It was found that the use of molecular sieves greatly improves this process by removing minute amounts of water present in the reaction medium. Water was found to deactivate the catalyst. All these developments led to an improved catalytic version that allows a five-fold increased substrate concentration relative to the stoichiometric method. Sensitive water-soluble, optically active glycidols can be prepared in an efficient manner by an in situ derivatisation. This epoxidation method appears to be competitive with enzyme-catalysed processes and was applied in 1981 for the commercial production of the gypsy moth pheromone, (-1-) disparlure, used for insect control (Eqn. (25)). [Pg.178]

The widespread use of economic poisons has a definite impact on the animal complex on the face of the earth which provides our sustenance. Already we have seen the use of DDT for codling moth control on apples result in a relatively minor pest becoming a serious threat. The same material used as a wonder spray for fly control now fails, after a couple years of common usage, with the appearance of new, resistant strains of flies. Bees and other pollinating insects as well as helpful predators or parasites may be decimated and their important aid be lost by untimely or improper use of most of the newer insecticides. [Pg.15]

In contrast to pheromones that involve single complex compounds, many moth species have been found to utilize a specific blend of relatively simple fatty acid-derived compounds. It appears that the evolution of a unique enzyme, A1 desaturase, used in combination with 2-carbon chain-shortening reactions (Figure 3) has allowed moth species to produce a variety of unsaturated acetates, aldehydes, and alcohols that can be combined in almost unlimited blends to impart species specificity. For example, biosynthetic precursors for the six-component pheromone blend of acetates for the cabbage looper moth (12) (Figure 2) can be determined easily from the cascade of acyl intermediates produced by the A11-desaturase and chain-shortening reactions (Figure 3). [Pg.118]

We also have evidence of how the female assesses the size of her mating partners. She appears to do so indirectly, by gauging the size of their spermatophore, for which purpose she may use stretch receptors that female moths are known to have in the chamber (bursa) in which spermatophores are deposited (29). Male Utetheisa can be caused to produce inordinately small spermatophores if they are mated relatively recently beforehand. If such mated males are placed in competition with physically smaller males, whose spermatophores may now be the relatively larger ones, they tend to "lose out" (30). We predict from this that males, in nature, may space their matings days apart. To regain the capacity to produce full size spermatophores takes a male about a week (30). [Pg.138]

In the case of the winter moth, tannins may very well reduce assimilation by complexlng with dietary proteins. However, the assumption that this is how tannins inhibit growth in species other than the winter moth needs to be carefully re-examined. In the experiments cited above, mechanisms other than a reduction in assimilation appear to be operating. [Pg.239]

Jermy (15) has emphasized the Importance of allomones in the host plant selection process. Although the ovlpositional and phagostimulative kalromones do not appear to be sufficient to account for host specificity by M. sexta in the host plant selection process, the mere avoidance of allomones does not appear to be sufficient either. Rather, the presence of a detectable allomone is sufficient to account for non-selection of a potential host plant. For example, given a choice between esculentum and any other suitable host plant M. sexta moths select 1. excu-lentum (16). No allomones are Involved To account for this preference, the presence of volatile orientation factor(s) may be Involved. In fact, Morgan and Lyon ( ) Isolated amyl salicylate from the host plant Datura stromonlum as an orientation factor for gravid female moths. We have also shown that an orientation factor is present in the steam distillate of esculentum leaves. [Pg.256]


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See also in sourсe #XX -- [ Pg.153 , Pg.157 , Pg.159 , Pg.160 , Pg.164 , Pg.166 , Pg.168 , Pg.171 , Pg.174 ]




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Appearance

Moths

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