Texas, USA 2010 - International Herbage Seed Group

Harvest methods and seed yield potential in Brachiaria hybridsE. A. Pizarro 1 , M. Hare 2 , J. H. Antezana Rojas 3 , R. R. Ramón 1 , I. G. Miranda 1 , A. Chávez Chena 1 , A.Balbuena 1 , and J. W. Miles 41 Grupo Papalotla, 2 Faculty of Agriculture, Ubon Ratchathani University, Thailand, 3 SEFO - SAM,Bolivia, 4 Centro Internacional de Agricultura Tropical, ColombiaE-mail: eapizarro@gmail.comAbstractUntil 2000, Brachiaria spp. cultivars were derived without genetic modification directly fromnatural germplasm collected in Africa. A breeding program was initiated at CIAT in 1988. Trialsdemonstrated the superiority of Mulato II, a vigorous, semi-erect grass with very deep andbranched roots giving it excellent drought resistance. Mulato II has excellent nutritional value:CP is in the range of 14 to 22% and IVDMD from 55 to 65%. These values, similar to temperategrasses, are unusual in warm-season grasses. Seeds yields are encouraging and are related withmanagement, harvest methods, and geographical locations.IntroductionUntil 2000, Brachiaria spp. cultivars were derived without genetic modification directly fromnatural germplasm collected in Africa.A breeding program, based on sexual germplasm kindly provided by C.B. do Valle (EMBRAPA-CNPGC), was initiated at CIAT in 1988, to combine desirable attributes found in accessions ofB. brizantha and B. decumbens. (Miles et al., 2004).Since the release of cv. Mulato II, a series of agronomic experiments have been conducted.Trials, demonstrated the superiority of Mulato II, a vigorous, semi-erect grass with very deep andbranched roots giving it excellent drought resistance, confirmed by results in the BrazilianCerrado, Central America, Mexico, Asia, as well as in the Argentine Chaco (Pizarro et al., 2008).Mulato II is the most innovative alternative to improve ruminant livestock productivity in thetropics (Pizarro et al., 2008).Mulato II has the potential to produce in excess of 500 kg ha -1 of pure seed, as evidenced byexperiments where an effort is made to recover all pure seed produced, either by bagginginflorescences or by opportune recovery of fallen seed (Hare et al., 2007c; Chávez Chena et al.,Personal communication). How much of this potential is realized in practice will depend onmany factors, including harvest method.Choosing an appropriate method for seed harvest depends firstly on the particular species,especially its growth habit and seed structure, the synchrony of crop development and relativeamounts of standing and fallen seed. Secondly, it depends on the availability of machinery orhand labor and finally, on previous experience.33