01860naa a2200289 a 450000100080000000500110000800800410001910000200006024500940008026000090017430000210018349000140020452008920021865000130111065000250112365000220114865000250117065000350119565000130123065000220124365000160126565300160128170000160129770000130131370000220132677302220134813228122009-03-17       2008    bl uuuu     u00u1 u    #d1 aVALLE, C. B. do  aPolyploidization of sexual diploid Brachiaria decumbens for intraespecific hybridization.  c2008  ap. 395 v. 2.      vv. 2.      aBrachiaria decumbens (D), also known as signalgrass, is the most widely adapted forage grass in the tropics. It was first introduced to Brazil in the early 1950´s and its best known cultivar, cv. Basilisk, quickly spread to the acid savannas of Latin America, covering millions of hectares. It is a natural tetraploid (4x) and apomitic genotype of good dry matter and seed production, even though it is susceptible to spittlebugs, the most widespread insect pest in tropical pastures. Breeding of this species was restricted to using 4 x apomictic accessions as pollen donors in interspecific crosses, since sexual genotypes are diploid (2x). Earlier attempts of interploydic crosses were unsuccessful (Ferguson and Crowder, 1974; Hacker, 1994). This paper is the first report of the use of in vitro culture and colchicines treatments in tetraploidizing sexual genotypes of signalgrass.  aApomixia  aBrachiaria Decumbens  aCultura de Tecido  aGramínea Forrageira  aMelhoramento Genético Vegetal  aPastagem  aPlanta Forrageira  aPoliploidia  aBraquiária1 aSIMIONI, C.1 aJANK, L.1 aRESENDE, R. M. S.  tIn: INTERNATIONAL GRASSLAND CONGRESS, 21.; INTERNATIONAL RANGELAND CONGRESS, 8., 2008, Huhhot, China. Multifunctional grasslands in a changing world: proceedings. Guangzhou: Guangdong People´s Publishing House, 2008.