?rea de concentra??o: Produ??o Vegetal / Submitted by M?rden L?les (marden.inacio@ufvjm.edu.br) on 2016-07-26T19:46:56Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Marcos_ Ant?nio_ da_ Silveira_ J?nior.pdf: 1864492 bytes, checksum: 8855c38c294d410e078b2af072e73b63 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-07-27T11:57:55Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Marcos_ Ant?nio_ da_ Silveira_ J?nior.pdf: 1864492 bytes, checksum: 8855c38c294d410e078b2af072e73b63 (MD5) / Made available in DSpace on 2016-07-27T11:57:55Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Marcos_ Ant?nio_ da_ Silveira_ J?nior.pdf: 1864492 bytes, checksum: 8855c38c294d410e078b2af072e73b63 (MD5) Previous issue date: 2015 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A produtividade m?dia das culturas aliment?cias ? considerada baixa e entre os fatores que mais impactam nessas perdas est? a competi??o com plantas daninhas. Nesse contexto, foram conduzidos tr?s experimentos com os objetivos de: a) determinar os efeitos da competi??o de capim marmelada (Urochloa plantaginea) e pic?o-preto (Bidens pilosa) em diferentes arranjos e densidades no crescimento das culturas do milho, do feijoeiro e da mandioca; b) quantificar a interfer?ncia e o efeito da associa??o do pic?o-preto e do capim marmelada no desenvolvimento da cultura, bem como o efeito da competi??o nas plantas daninhas e c) avaliar a interfer?ncia de pic?o-preto e capim marmelada em lavouras de feij?o, bem como seu efeito em diferentes doses de fertilizantes. No primeiro experimento constatou-se que o incremento da densidade de plantas daninhas afeta negativamente o crescimento das culturas, especialmente as culturas do feijoeiro e da mandioca. Nas parcelas onde o pic?o-preto se encontrava presente as plantas cultivadas mostram maior sensibilidade ? competi??o em rela??o ?s parcelas onde a capim marmelada se encontrava presente. No segundo trabalho observou-se que o pic?o-preto exerce maior competi??o sofre o feijoeiro do que o capim marmelada. A associa??o das duas esp?cies daninhas mostrou tend?ncia de ser mais danosa, do que quando associadas, ao crescimento da cultura do feijoeiro. No terceiro trabalho, o efeito da competi??o entre cultura e plantas daninhas promoveu perdas no desenvolvimento do feijoeiro, que s?o agravadas pela redu??o da quantidade de adubo presente no substrato, destacando-se que os efeitos s?o mais quando ? utilizada a dose recomendada dos fertilizantes. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / ABSTRACT The average productivity of food crops is considered low and among the factors that impact these losses is the competition with weeds. In this context, three experiments were performed with the following objectives: a) to determine the effects of marmalade grass competition (Urochloa plantaginea) and beggarticks (Bidens pilosa) in different arrangements and densities in the growth of the corn, bean and cassava crops; b) quantify the interference and the association effect of beggarticks and marmalade grass in the development of culture as well as the effect of competition in the weeds and c) evaluate the interference of beggarticks and marmalade grass in bean crops, as well their effect at different doses of fertilizers. In the first experiment it was found that the increase in weed density negatively affect the growth of crops, especially crops of beans and cassava. In plots where the beggartick was present cultivated plants show greater sensitivity to the competition in relation to the portions where the jam grass was present. In the second study it was observed that beggarticks exerts greater competition suffers the bean that marmalade grass. The combination of the two weed species tended to be more damaging than when associated to the growth of the bean crop. In the third paper, the effect of competition between crop and weeds promoted losses in the development of the bean, which are compounded by reducing the amount of fertilizer present in the substrate, highlighting that the effects are more when the recommended dose of fertilizer is used.