توضیحات
ABSTRACT
The root growth of most crop plants is inhibited by soil salinity. Roots respond by modulating metabolism, gene expression and protein activity, which results in changes in cell wall composition, transport processes, cell size and shape, and root architecture. Here, we focus on the effects of salt stress on cell wall modifying enzymes, cellulose microfibril orientation and non-cellulosic polysaccharide deposition in root elongation zones, as important determinants of inhibition of root elongation, and highlight cell wall changes linked to tolerance to salt stressed and water limited roots. Salt stress induces changes in the wall composition of specific root cell types, including the increased deposition of lignin and suberin in endodermal and exodermal cells. These changes can benefit the plant by preventing water loss and altering ion transport pathways. We suggest that binding of Na+ ions to cell wall components might influence the passage of Na+ and that Na+ can influence the binding of other ions and hinder the function of pectin during cell growth. Naturally occurring differences in cell wall structure may provide new resources for breeding crops that are more salt tolerant.
INTRODUCTION
Plant evolution has resulted in a large array of mechanisms to tolerate the stresses associated with increased soil salinity. However, for most cereal crops the growth of roots is disrupted when soil salinity exceeds 4 dS/m, equivalent to about 40 mM NaCl. Increased soil salinity exposes plants to ionic sodium (Na+) and chloride (Cl–), which leads to a cascade of responses in the plant due to the ionic and osmotic components of salt stress. Salt stress can indirectly affect cell wall properties by causing changes in gene expression, but Na+ can also physically interact with the cell wall components directly, and change their chemical properties. An increase in soil salinity results in accumulation of Na+ in the apoplast, which can lead to an increase in interactions between Na+ and negatively charged sites within cell wall polymers, and also influence apoplastic pH.
Year: ۲۰۱۸
Publisher : ELSEVIER
By : Caitlin S. Byrt, Rana Munns, Rachel A. Burton, Matthew Gilliham, Stefanie Wege
File Information: English Language/ 9 Page / size: 631 KB
سال : ۱۳۹۶
ناشر : ELSEVIER
کاری از : کییتلین S. Byrt، Rana Munns، Rachel A. Burton، Matthew Gilliham، Stefanie Wege
اطلاعات فایل : زبان انگلیسی / 9 صفحه / حجم : KB 631
نقد و بررسیها
هنوز بررسیای ثبت نشده است.