Abscisic acid development

Whenham, R.J., Fraser, R.S.S., Brown, L.P. Payne, J.A. (1986). Tobacco-mosaic-virus-induced increase in abscisic-acid concentration in tobacco leaves Intracellular location in light and dark-green areas, and relationship to symptom development. Planta, 168, 592-8. 

Quarrie, S.A. Jones, H.G. (1977). Effects of abscisic acid and water stress on development and morphology of wheat. Journal of Experimental Botany, 28, 192-203. 

In the natural world, carotenoid oxidation products are important mediators presenting different properties. Volatile carotenoid-derived compounds such as noriso-prenoids are well known for their aroma properties. Examples include the cyclic norisoprenoid P-ionone and the non-cyclic pseudoionone or Neral. Carotenoid oxidation products are also important bioactive mediators for plant development, the best-known example being abscisic acid. Apo-carotenoids act as visual and volatile signals to attract pollination and seed dispersal agents in the same way as carotenoids do, but they are also plant defense factors and signaling molecules for the regulation of plant architecture. 

Chono, M., I. Honda et al. (2006). Field studies on the regulation of abscisic acid content and germinability during grain development of barley Molecular and chemical analysis of pre-harvest sprouting. J. Exp. Bot. 57(10) 2421-2434. 

Harada, J.J., De-Lisle, A.J., Bakden, C.S. Crouch, M.L. (1989). Unusual sequence of an abscisic acid-inducible mRNA which accumulates late in Brassica napus seed development. Plant Molecular Biology 12, 395-401. 

Smart, C.C. Trewavas, A.J. (1984). Abscisic-acid-induced turion formation in Spirodela polyrrhiza L. III. Specific changes in protein synthesis and translatable RNA during turion development. Plant, Cell and Environment 7, 121-32. 

Heino, P., Sandman, G., LSng, V., Nordin, K. Palva, E.T. (1990). Abscisic acid deficiency prevents development of freezing tolerance in Arabidopsis thaliana (L.) Heynh. Theoretical and Applied Genetics 79, 801-6. 

There are two important classes of allelochemicals synthesized by oxidative cleavages of tetraterpene carotenoids. One is the plant hormone abscisic acid (ABA, 31) that plays important roles in growth and development of plants, especially in seed development and dormancy.17 Dry dormant seeds contain relatively large amounts of ABA, particularly in the seed coats. ABA and phenolic allelochemicals in the seed coats are easily released into the environment when the seeds are imbibed, resulting in inhibition of seed germination and seedling growth of plants in the vicinity. Both ABA and the phenolic compounds are rapidly broken down in the soil, and therefore the inhibition is short-lived. 

Over the intervening 25 years, there have been no mjor developments with respect to the use of abscisic acid, either in the native or derivatized form, in agriculture. The early premise that the oonpound showed for ocntrolling the breaking of dormancy in stored products such as Irish and sweet potatoes, onions, carrots, and other oonmodities, has not materialized. Nether has a use been... 

ABSTRACT More than 100 abscisic acid (ABA) analogs have been reported so far. Some were synthesized to clarify structure-activity relationships, and others were developed as tools for investigating the molecular mechanism of ABA action. These analogs, especially those that can be useful tools for studying ABA reception and catabolic inactivation, are summarized together with their design concepts, structural properties and bioactivities. 

Ethylene physiology of the plant can be manipulated in a variety of ways. In the past, the use of ethylene was limited to exposure of plants to the gas in containers thus, fleld applications were impractical. This limitation was removed by the discovery and commercial development of ethephon in which the liquid active ingredient, 2-chloroethyl phos-phonic acid, is converted to ethylene by the plant (59). Other means of modifying ethylene physiology have been recognized and discussed (4, 5). It is possible to stimulate ethylene synthesis with auxins (60, 61, 62, 63), abscisic acid (64), defoliants (65), ascorbic acid (66), cyclohexi-mide (66), and iron salts (66), among other compounds. A number of physical, environmental, microbial, and insect stresses increase ethylene synthesis, including moisture stress (67) and air pollutants (68). 

At times when a plant needs to slow down growth and assume a resting stage (dormant), abscisic acid is produced in the terminal bud, which slows down growth and directs the leaf primordia to develop scales that protect the dormant bud during winter. Since the hormone also inhibits cell division in the vascular cambium, both primary and secondary growth is put on hold during winter. 

The 1,1-didesmethyl analogue (181) of abscisic acid (23) has been prepared.110 The cis-trans photoisomerization of (23) has been studied.111 A convenient procedure has been developed for the catalytic hydrogenation of p-ionone (142) to the m-5,6-dihydroionone (182).112 On treatment with Me2S+ CH, p-ionone gave the epoxide (183), which with MgBr2 afforded the aldehyde (184) without halohydrin formation.113... 

Until the discovery of brassinolide by USDA scientists in 1979, it was thought that only five groups (indole auxins, gibberellins, cytokinins, abscisic acid, and ethylene) of hormones were responsible for regulating plant growth and development. Following this discovery, a number of compounds similar to brassinolide both in structure and physiological activity were isolated from different parts of plants. On the basis of published... 

Abscisic acid (ABA) levels in rice plants, 308,31Or levels in squash hypocotyls, 315/.316 Active component of brassins identification, 9,lQf pilot plant extraction, 6,7/,8 solvent partition and column chromatography, 8 Adventitious root(s) development, 233,234r,235 formation, 247 Agriculture, application of 24-epibrassinolide, 280-290 22-Aldehydes, synthesis of brassinosteroids, 47-50f a hormone function, description for brassins, 4... 

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