标题：Avaliação de herbicidas para o estabelecimento de grama estrela por mudas com raiz em pastagens degradadas de braquiária Evaluation of herbicides to the establishment of stargrass by seedlings with root in degraded pastures of brachiaria
出版社：Universidade Estadual do Centro-Oeste do Paraná, UNICENTRO
摘要：Em áreas de pastagens degradadas de Brachiaria , o significativo banco de sementes e a agressividade das plantas originadas destas, limitam sua substituição por outras forrageiras.Neste ensaio, buscou-se o estabelecimento por mudas de grama estrela com raiz em plantio convencional e o controle das plântulas de Brachiaria oriundas de sementes com herbicidas.Os tratamentos foram: Premerlim N.A.(Trifuralin 2,1 kg ha-1) aplicado logo após o plantio e em pré-emergência das plantas daninhas e Fortex (MSMA Diuron, 1,08 i.a.kg ha-1 i.a. 0,42 i.a.kg ha-1 i.a), Primestra Gold (Atrazine metolachor 1.202,5 i.a.kg ha-1 e 942,5 i.a.kg ha-1), Primóleo (Atrazine 1,0 i.a.kg ha-1), Sanson (Nicosulfuron 40 i.a.kg ha-1), aplicados em pós-emergência, 20 dias após o plantio das mudas e uma testemunha sem herbicidas.Trifluralin, Diuron MSMA e Nicosulfuron foram efetivos no controle das braquiárias, porém, este último, na dose utilizada, causou elevada fitotoxidade na grama estrela.Abstract In areas of degraded Brachiarias pasture, the meaningful soil seed bank and its aggressive plants restrict their replacement by other forage crops.In this experiment, the goal is to organize star grass seedlings with roots in conventional planting, and to control Brachiaria seedlings produced from seeds with herbicides.The treatments were: Trifuralin (2, I kg ha-l) applied afterward the planting and in preemergency of the weeds and MSMA Diuron (1,08 i.a.Kg ha-l i.a. 0,42 i.a.Kg ha-l i.a.), Atrazinemetolachor 1.202,5 i.a.Kg ha-l e 942,5 i.a.Kg ha-l) Atrazine (1,0 i.a.Kg ha-l); Nicosulfuron (40 i.a.Kg ha-l) applied in post-emergency, twenty days after the planting of the seedling and a control without herbicide application.Trifuralin, Diuron MSMA and Nicosulfuron were effective to control the Brachiarias.However, the latter, in the dosage used, caused an increasing fitotoxity in the star grass.
