02315cab a2200301Ia 4500001000800000003000600008008004100014040000800055041001300063090002500076100002600101240009700127245008600224300001700310504002400327520133700351546002301688650001201711650001801723650002201741650001801763650001901781773009801800856008001898596000601978942001201984999001701996u184868SIRSI100913s2007 ua ss b eng d aEAL aengbara aART MUJAS V32 No3 251 aAbd AL- Mageed, H. A.10aMansoura University journal of agricultural sciences, 2007 v.32 (3) h[electronic resource].14aThe effect of brassinosteroid on cotton fiber developmenth[electronic resource]. ap.1905-1914. aIncludes reference. aThe current understanding of the role of phytohormones in the development of cotton fibers is derived largely from an amenable culture system in which cotton ovules, collected on the day of anthesis, are floated on liquid media. Under these conditions, supplemental auxin and gibberellin were found to promote fiber Initiation and elongation. More recently, addition of low concentrations of the brassinosteroid brassinolide (BL) were also found to promote fiber elongation while a brassinosteroid biosynthesis inhibitor brassinazole2001 (Brz) inhibited fiber development. This present results confirm that exogenous BL promotes fiber elongation while treatment with Brz inhibits It. Furthermore, treatment of cotton ftoral buds with Brz results in the complete absence of fiber differentiation, Indicating that BR is required for fiber initiation as well as elongation. Expression of fiber genes associated with cell elongation increased in ovules treated with BL and was suppressed by Brz treatment ,establishing a correlation between brassinosteroid - regulated gene expression and fiber elongation. These results establish a clear connection between brassinosteroid and fiber development and open the door for genetic analysis of cotton development through direct modification of the brassinosteroid signal transduction pathway. aSummary in Arabic. 0aCotton. 3aCotton fiber. 0aBrassinosteroids. 0aBrassinolide. 3aOvule culture.0 tMansoura University journal of agricultural sciences.g2007.v.17(3)x1110-03467nnaswu18219740auhttp://nile.enal.sci.eg/EALE/2007/MUJAS/3207/3/1905.pdfzFull Text Article a1 cAR2lcc c40286d40286