Auxin induced growth, effect

Sci Rep Tohoku Univ Foruth Ser Biol 27 199-207 Wada S, Nagao M (1960) Effect of guaiacol on the auxin-induced growth of rice coleoptile sections. Sci Rep Tohoku Univ Fourth Ser Biol 26 181-188 Walton DC (1980) Biochemistry and physiology of abscisic acid. Annu Rev Plant Physiol 31 453-489... 

Hag L, Curtis RW (1968) Production of ethylene by fungi. Science 159 1357-1358 Imaseki H, Pjon C-J (1970) The effect of ethylene on auxin-induced growth of excised rice coleoptile segments. Plant Cell Physiol 11 827-829 Imaseki H, Pjon C-J, Furuya M (1971) Phytochrome action in Oryza sativa L. IV. Red and far-red reversible effect on the production of ethylene in excised coleoptiles. Plant Physiol 49 631-633... 

In this context, we recently discovered close correlations between auxin-induced ethylene synthesis, massive accumulations of ABA in root md even more in shoot tissue and inhibition of their growth. This phenomenon, which has been reported for the first time, was demonstrated for auxin herbicides from different chemical classes (Figure 1), such as quinmerac, quinclorac, MCPA, naphthalene acetic acid, dicamba and picloram, and lAA at high concentration, in a variety of dicot species, including members of the Sola-naceae, Umbelliferae, Fabaceae, Scrophulariaceae and Brassicaceae [35, 39, 40]. ABA accumulation and concomitant epinastic effects and reduced shoot growth were also... 

A second effect of ethylene is to alter the direction of cell enlargement in stems and roots [81]. By causing a change in orientation of cellulose microfibrils from transverse to random or longitudinal, it causes cells to swell up rather than elongate. As a result, stems and roots become shorter and thicker. The inhibition of stem and root growth induced by excess auxin is due in part to auxin-induced ethylene [82]. In a few tissues, such as... 

Auxin has been implicated in a bewildering array of growth responses. At the level of the cell, these responses involve rapid changes in cell expansion, effects on cell division and meristem activity, as well as differentiation of specific cell types [1]. In an effort to understand molecular aspects of auxin signaling, many researchers have focused on rapid biochemical responses associated with auxin-induced cell elongation. These include activation of a plasma membrane H -ATPase [2], changes in the behavior of ion channels... 

Auxin only induced growth in segments of rice coleoptile when the cell wall was rich in non-cellulosic D-glucose residues.The effect decreased with age and with the total amount of non-cellulosic polysaccharide present. A decrease in the relative amount of non-cellulosic D-glucose and an increase in the content of D-xylose residues were found in the growth cycle of cell walls of rice coleoptiles irrespective of the culture conditions. ... 

One of the most potent factors in the regulation of lAA biosynthesis may be lAA itself. lAA appears to suppress its own biosynthesis in decapitated coleoptiles (Anker 1973), and certain auxin-induced modifications of growth patterns have been attributed in part to effects on endogenous auxin production (Evans and Schmitt 1975, Evans et al. 1977). Red light-induced suppression of auxin production in coleoptile tips may result from a suppression of auxin movement out of the tip leading to feedback inhibition of auxin biosynthesis (Huisinga 1976). 

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