Plant selectivity

Addressing transportation risk at various life cycle stages can increase the inherent safety of the overall operation. For example, this may mean minimizing the number of railcars sitting on track within or outside the plant, selecting suppliers close to the plant, and so on. This chapter provides an overview of inherently safer concepts applied to transportation. 

Equipment Availability. In many cases the equipment is not available off the shelf, and the delivery time may be lengthy hence, adequate planning is necessary to ensure that the commissioning date can be met with the plant selected. 

A gas processing plant selectively extracts ethylene and ethane from an incoming natural gas mixture stream. These two light hydrocarbons are absorbed in a heavy gasoline type absorber oil, and then stripped with open steam in an open tower. The system data are (see Figure 8-41) ... 

Note The petroleum, petrochemical, chemical, and other industrial plants must specify or select the design/fabrica-tion code designation for their individual application as the standards do not dictate the code designation to use. Many chemical plants select the most severe designation of Class R rather than Class B primarily because they prefer a more rugged or husky piece of equipment. 

A practice somewhat related to crop rotation is crop diversification or polyculture (36). This approach involves planting selected combinations of crops, like corn and beans. 

From 1980 to 1993, the number of safety-relevant plants increased from 65 to 772 [173]. They constituted slightly more than a quarter of all plants (3472) at that time. Concerning big chemical plants, selected as falling into the category of a special law [173], 230 out of 346 plants were safety-relevant 163 of them, in addition, had special obligations. 

Pilot Plant—Chemical reaction hazards Influence of plant selection on hazards Definition of safe procedures Effects of expected variations in process conditions Definition of critical limits... 

Arnold TM, TargettNM, Tanner CE, Hatch WI, Ferrari KE (2001) Evidence for methyl jasmonate-induced phlorotannin production in Fucus vesiculosus (Phaeophyceae). J Phycol 37 1026-1029 Bemays EA, Chapman RF (1994) Host-plant selection by phytophagous insects. Chapman Hall, New York... 

Uses Dormant ovicidal spray for fruit trees (highly phototoxic and cannot be used successfully on actively growing plants) selective herbicide and insecticide. 

Bernays, E. A. and Chapman, R. F. 1994. Host-Plant Selection by Phytophagous Insects. London Chapman Hall. 

Visser, J.H. "Olfaction in the Colorado Beetle at the Onset of Host Plant Selection" Thesis, Agricultural University, Wageningen, 1979. 

The host range of the tobacco hornworm (Manduca sexta) is limited to selected members of the family Solanaceae. In an effort to better understand the chemical basis for the host plant selection process, we have undertaken an examination of both hornworm preferred and non-preferred members of the Solanaceae. Our investigations have shown this tc be a complex system involving the subtle interaction between such behavioral modulators as (1) Ovipositional stimulants (2) Feeding stimulants and imprinters (3) Anti-feedants (A) Repel-lants (5) Insecticides. The results of these investigations will be discussed. 

BORDNER ET AL. Chemical Basis for Host Plant Selection... 

Although the ovipositional stimulant and the phagostlmulant are necessary to illicit their respective responses, they may not be sufficient to account for host-plant selection. In the case of Nicandra physaloldes, a member of the Solanaceae not preferred as a host plant by M. sexta, we have shown that aqueous extracts... 

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. 

In a similar fashion, if a recombinant or mutation occurred in a population of insects that enabled individuals to feed on some previously protected group of plants, selection would carry that line into a new adaptive zone (4). Here the new group would be able to diversify with little competition from other phytophagous insects. All in all, the diversity of plants would tend to augment the diversity of Insects and the diversity of phytophagous insects would tend to enhance the diversity of plants. 

Each step in the process of host-plant selection may be mediated by plant components. Both the secondary chemistry and nutritional value play a major role in the suitability of the host. 

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