Effect of herbicides on desiccation of Lolium multiflorum L. plants and seed germination Efeito de herbicidas na desseca o e germina o de sementes remanescentes de Lolium multiflorum L.

A trial was carried out to evaluate efficacy of different herbicides and spray volumes when sprayed to ryegrass for chemical management and control of remaining seeds. The treatments were: three formulations of glyphosate at 1080 g ha-1 (Original Round up, Round up Transorb, WG Round Up), paraquat + diuron at 300+500 and 150+250 g ha-1 and glufosinate ammonium at 400 and 600 g ha-1. All treatments were used in spray volumes of 200 and 400 l ha-1. The effectiveness of the desiccation of ryegrass plants was assessed at 1, 3, 7, 14 and 21 days after application. At the last evaluation samples were collected for dry mass production analysis, and also panicles with seeds for germination test. Glyphosate in different formulations and volumes and glufosinate ammonium at 600 g ha-1 when sprayed with into 400 l ha-1 provided the best controls regarding ryegrass chemical management. Treatments with gliphosate (Roundup Original) and paraquat + diuron (300 +150 g ha-1) in volumes of 400 and 200 L ha-1, respectively, were the ones that showed the lowest values of dry matter, differing from the control. All the ryegrass seeds were killed by treatments with herbicides (paraquat + diuron) at 500 +250 g ha-1 and glufosinate-ammonium at 600 g ha-1 when used 200 l ha-1. O objetivo desse trabalho foi o de avaliar a eficácia de diferentes herbicidas aplicados em pósemergência na desseca o de plantas de azevém e viabilidade de sementes remanescentes do controle, com diferentes volumes de calda de aplica o. Os tratamentos testados foram: três formula es de glyphosate na dose de 1.080g ha-1 (Roundup Original, Roundup Transorb, Roundup WG), paraquat + diuron nas doses de 300 + 150 e 500 + 250g ha-1 e am nio-glufosinate nas doses de 400 e 600g ha-1. Em todos os tratamentos foram utilizados os volumes de aplica o de 200 e 400L ha-1. A eficácia na desseca o de plantas de azevém foram avaliados aos 1, 3, 7, 14 e 21 dias após aplica o, sendo que nesta última avalia o foram coletadas plantas para a análise de produ o de matéria seca, assim como panículas com sementes para testar a sua viabilidade. A desseca o do azevém com o herbicida glyphosate nas diferentes formula es e volumes testados, bem como o herbicida am nio-glufosinate na dose de 600g ha-1 no volume de aplica o de 400L ha-1 proporcionaram os melhores controles. Os tratamentos com gliphosate (Roundup Original) e paraquat+diuron (300+150g ha-1), nos volumes de 400 e 200L há-1, respectivamente, foram os que proporcionaram os menores valores de matéria seca, diferindo da testemunha. Todas as sementes remanescentes d