Control, of plants

Economic Market. The spice trade is controlled by many direct elements and responds slowly to supply and demand fluctuations. Resupply depends on growth to plant maturity, which for certain items, such as black pepper or nutmeg, can be several years. The raw material is directly affected by climate, adverse weather conditions, and control of plant diseases and insect and animal pests. Limited agricultural scientific advances are appHed to the cultivation of the botanicals, and there are many grades of product and degrees of quahty caused by different growing or processing conditions, sometimes by unknown factors as well. 

Control of Plant and Process Modifications Many accidents have occurred because plant or process modifications had unforeseen and unsafe side effects (Sanders, Management of Change in Chemical Plants Learning from Ca.se Histories, Butterworth-Heinemann, 1993). No such modifications shoiild therefore be made until they have been authorized by a professionally quahfied person who has made a systematic attempt to identify and assess the consequences of the proposal, by hazard and operability study or a similar technique. When the modification is complete, the person who authorized it... 

One of the economically most important areas in the control of plant processes is defoliation—the intentional removal of leaves. Large quantities of several chemicals currently are employed for this purpose, including magnesium chlorate and DEF (S,SyS-tributyl phosphor otrithioate), and the principal commercial value is for defoliation of cotton. Several synthetics such as 4-chlorophenoxyacetic acid and naphthalene-1-acetic acid are used to provide the opposite but related effect of retarding or limiting fruit drop in apples, stone fruits, and grapes. 

Cosgrove, D.J. (1986). Biophysical control of plant cell growth. Annual Review of Plant Physiology, 37, 377-405. 

A. Rovira, M. Ryder and A, Harris, Biological control of root diseases with p.seu-domonads. Biological Control of Plant Diseases, (E. S. Tjamos, ed.). Plenum Press, New York. 1992, p. 175. 

Y. Henis and 1. Chet, Microbiological control of plant pathogens. Advances in Applied Microbiology 79 85 (1975). 

R. J. Cook and K. F. Baker, The Nature and Practice of Biological Control of Plant Pathogens. American Phytopathology Society, St Paul, Minnesota, 1983, p539. 

Figure 9 Structures of some metabolites produced by fluorescent Pseudomonas spp. involved in biological control of plant disea.se in the field. (From Ref. 48.)...

Another definition of an evaluation-case event is "that incident outcome for which an engineered solution or a management system solution could be found that would reasonably prevent its occurrence," or more simply put, an event that could be preventable. All human-caused accidents and the consequences of some natural occurrences (earthquake, wind, waves) can be defined as preventable. However, we are only interested in events where engineering and management system parameters could have prevented the accident provided they are within reasonable control of plant personnel. 

These results show that the 2,4-dichlorophenoxyacetic acid can remain stable, and exert its herbicidal effects, only during the initial lag phase before the rapid logarithmic phase of destruction takes place. This initial lag phase depends upon the previous treatment of the soil, particularly on whether it has already been exposed to 2,4-dichlorophenoxyacetic acid. Clearly, once a soil is enriched with 2,4-dichlorophenoxyacetic acid destroying organisms, the herbicide, if added to the soil, will have little or no value in the control of plants growing there. 

Adams, P. B. (1990). The potential of mycoparasites for biological control of plant diseases , Annual Review of Phytopathology, 28, 59-72. 

Cook RJ, Baker KF (1983) The nature and practice of biological control of plant pathogens. 

Lamberti F, Greco N (1991) Effectiveness of soil solarization for control of plant parasitic nematodes. In DeVay JE, Stapleton JJ, Elmore CL (eds) Proceedings of the first international conference on soil solarization, Amman, Jordan, 19-25 February 1990. FAO Plant Protection and Production Paper No. 109, FAO, Rome, Italy, pp 167-172 Lamberti F, D Addabbo T, Greco P, Carella A, De Cosmis P (2000) Management of root-knot nematodes by combination of soil solarization and fenamiphos in southern Italy. Nematol Medit 28 31 15... 

Theron JM, Donald DGM, Broembsen SL, Van der Merwe JA (1982) The effect of warm water treatment of Pinus radiata seedlings on mycorrhizae survival, root growth capacity and Phytophthora eradication. S Afr For J 123 31-35 Thomashow LS, Weller DM (1990) Application of fluorescent pseudomonads to control root diseases of wheat and some mechanisms of disease suppression. In Hornby D (ed) Biological control of plant pathogens. CABI, Wallingford, UK, pp 109-122... 

A simple TLC method has been developed for the separation and identification of flavons and flavon glycosides in the extract of Phillyrea latifolia L. The leaves (100 g) were defatted in 11 of chloroform for 24 h and then extracted with 2 X 11 of ethanol-water (80 20, v/v). The collected extracts were concentrated and extracted again with n-hexane to remove chlorophylls and other apolar constituents. Analytes were extracted with ethyl acetate. Both normal phase and RP-TLC have been used for the separation of flavonoids. The results are compiled in Table 2.36. It was concluded from the data that TLC can be successfully applied for the quality control of plant extracts containing various flavone derivatives [124],... 

Chemical engineering is no longer confined to purely physical processes and the unit operations, and a number of important new topics, including reactor design, automatic control of plants, biochemical engineering, and the use of computers for both process design and control of chemical plant will be covered in a forthcoming Volume 3 which is in course of preparation. 

Uses A mixture containing cis and trans isomers is used as a soil fumigant for control of plant-parasitic nematodes. 

Control of Plant Some managers have a concern about losing control of their facility... 

The use of antibiotics for the control of plant virus diseases( ) is of interest. Several antibiotics have been tested for inhibition of replication of viral nucleic acid and/or protein synthesis within the host cell. Chloramphenicol, cycloheximide, actinomycin D and others are the most used antibiotics and the disease caused by tobacco mosaic... 

The avermectins, a family of compounds with potent anthelmintic, insecticidal and acaricidal activity, have vividly demonstrated that fermentation products can have entirely unanticipated activities. Besides their utility in animals, they show great promise for the control of insect pests of plants. Although antibiotics have found only a limited role in the control of plant diseases, the desire to find environmentally acceptable alternatives to the chemicals currently used has prompted new research efforts to discover fermentation products for use as pesticides. 

Fermentation products have played a rather minor role in the control of plant diseases. Table VI gives a classification of agents used on plants. These are divided into pesticides and growth modulators. The pesticides are classified as bactericides, fungicides, insecticides, miticides, nematicides and herbicides. There are fermentation products in each of these categories, and these are listed in Table VII. 

Dong LQ, Zhang KQ, Microbial control of plant-parasitic nematodes A five-party interaction, Plant Soil 288 31 5, 2006. 

Beck, S. D. In "Proceedings of the Summer Institute of Biological Control of Plant Insects and Diseases" Maxwell, F. G. Harris, F. A., Eds. Univ. Press of Mississippi Jackson, 1974 pp. 290-311. 

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