Ethylene seed germination

The various fumigants often exhibit considerable specificity toward insect pests, as shown in Table 8. The proper choice for any control operation is determined not only by the effectiveness of the gas but by cost safety to humans, animals, and plants flammabdity penetratabdity effect on seed germination and reactivity with furnishings. The fumigants may be used individually or in combination. Carbon tetrachloride has been incorporated with carbon disulfide, ethylene dichloride, or ethylene dibromide to decrease flammability, and carbon dioxide is used with ethylene oxide for the same purpose. 

None of these compounds has been reported in natural stimulant preparations. Similarly, Riopel 2) in a more recent review noted that many compounds promote or inhibit seed germination. Ethylene is an effective germinator, but its use in under developed countries is minimal. 

Ethylene as a regulator of seed germination and seedlings growth 111... 

Ethylene is a potent inductor of Striga spp. germination.26 It has been hypothesized as a possible mechanism for parasitic seed germination that attachment of the inductor to the receptor s site triggers a cascade of biosynthetic reactions leading to the synthesis of the enzymes necessary for ethylene production.12... 

Eplee, R.E. 1975. Ethylene a witchweed seed germination stimulant. Weed Sci. 23, 433-436... 

PETRUZZELLI, L., KUNZ, C., WALDVOGEL, R., MEINS, F., JR., LEUBNER-METZGER, G., Distinct ethylene- and tissue-specific regulation of beta-1,3-glucanases and chitinases during pea seed germination., Planta, 1999, 209, 195-201. 

Alkenes are unsaturated hydrocarbons that contain at least one C=C bond. The simplest alkene is CH2=CH2, called ethene (lUPAC) or ethylene, which plays important roles as a plant hormone in seed germination and fruit ripening. The next member of the series is CH3 — CH = CH2, called propene or propylene. Alkenes with four or more carbon atoms have several isomers. For example, the alkene C4H8 has the four structural isomers shown in A FIGURE 24.7. Notice both their structures and their names. 

Abe H, Uchiyama RM, Sato R, Muto S (1974) Plant growth regulators occurring in marine algae. In Plant growth substances 1973. Hirokawa, Tokyo, pp 201-206 Abeles FB (1966) Auxin stimulation of ethylene evolution. Plant Physiol 41 585-588 Abeles FB (1973) Ethylene in plant biology. Academic Press, London New York Abeles FB, Lonski J (1969) Stimulation of lettuce seed germination by ethylene. Plant Physiol 44 277-280... 

Experiment II. Volatile compounds from leaves and bulbs Volatiles (terpenoids, ethylene and other compounds) can be released from the leaves and other plant parts and consequently can affect the germination of seeds, growth and development of neighbouring plants in ecosystems. 

ABA produce more mature seeds showing primary dormancy than the wild-type plants. A reduced dormancy often occurs in seeds of ABA-insensitive mutants. Gibberellin A (GA) is absolutely required for germination of the wild-type Arabidopsis seeds. Seeds of ethylene-insensitive and GA-insensitive mutants are supersensitive to exogenous ABA, which suggests that in imbibed seeds ethylene and GA may directly counteract the action of ABA in dormancy maintenance. ... 

Figure 15—3 lays out the four-step process, starting with germinating the seed from which everything sprouts. Triethyl aluminum is created from aluminum, hydrogen, and ethylene in step one, which itself has several parts. Powdered aluminum in a toluene slurry is fir-st converted to diethyl aluminum hydride, HA1(C2H5)2, at 212—300 F and 1500 psi. This product is then fed to a tubular reactor with ethylene at 212 F and 300 psi to produce triethyl aluminum. Yields are about 90%. 

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