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-Some desiccation techniques for harvesting wheat may affect seed quality. The objective of this study was to evaluate the effect of different desiccant herbicides applied to the wheat crop and their effects on the production and seed quality. The experiment was conducted with cultivar CooDeteC 150 (CD 150) in two sites in Palotina (Paraná state, Brazil) with a randomized block design consisting of 7 treatments (desiccation herbicides) and 4 replications. Desiccation was realized when 50% of the plants were in stage 80 with seeds in powdery or mass consistency. the variables analyzed were percentage of moisture content after harvest, Yield, hectoliter weight, mass of 100 seeds, vigor, germination, fresh mass of seedlings, dry mass of seedlings and root length. the herbicides carfentrazone-ethyl and clethodim were the ones that promoted greatest reduction in vigor. the herbicide paraquat caused reduction in seedling length. there was a reduction in the mass of 100 seeds for glufosinate-ammonium, clethodim, diquat and carfentrazone-ethyl. Glufosinate-ammonium, paraquat, glyphosate, clethodim and diquat caused reduction in yield. Desiccation of Cultivar CD 150 at stage 80 is not recommended, since plant Yield and physiological seed parameters were adversely affected by herbicides.Index terms: chemical desiccation, management, germination, vigor, seedlings.Produtividade e qualidade fisiológica das sementes de trigo após dessecação com diferentes herbicidas RESUMO -Algumas técnicas de manejo da cultura do trigo, como a dessecação pré-colheita podem afetar a produtividade e a qualidade fisiológica das sementes. O objetivo deste estudo foi avaliar o efeito de diferentes herbicidas dessecantes aplicados na cultura do trigo e seus efeitos sobre a produtividade e a qualidade das sementes. O experimento foi conduzido com a cultivar COODETEC 150 (CD 150), em dois ambientes de produção localizados no Município de Palotina -PR, sob o delineamento experimental de blocos casualisados, constituído de 7 tratamentos (herbicidas na dessecação) com 4 repetições. A dessecação foi realizada quando 50% das plantas apresentavam-se no estádio 80 com as sementes de consistência farinácea ou de massa. As variáveis analisadas foram umidade após a colheita, produtividade de sementes, peso hectolitro, massa de 100 sementes, germinação e vigor. Os herbicidas carfentrazoneethyl e clethodim reduziram o vigor das sementes produzidas, e o herbicida paraquat reduziu o comprimento de plântulas. ocorreu redução na massa de 100 sementes para o amônio -glufosinate, clethodim, diquat e carfentrazone-ethyl. O amônio -glufosinate, paraquat, glyphosate, clethodim e diquat reduziram a produtividade. A dessecação de plantas da cultivar CD 150 no estádio 80 não é recomendada, em decorrências dos efeitos negativos dos herbicidas nos parâmetros produtivos e fisiológicos das sementes de trigo.Termos para indexação: dessecação química, manejo, germinação, vigor, plântulas.

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Horseweed (Conyza spp.) is a weed with a considerable presence and frequency throughout Brazilian crops, as well as presenting difficult chemical control. The objective of this study was to evaluate the efficiency of herbicide management, through single and sequential applications, in controlling Conyza spp., at two development stages with 4 to 6 leaves (3 to 5 cm) and 20 leaves (15-20 cm). The analyzed variables were: control percentage (7, 14, 21, and 28 days after application), dry matter content (28 days after application) and regrowth percentage (21 days after application). Data were submitted to analysis of variance at 5% probability and when there was a difference, the means were submitted to the Scott-Knott test. For Conyza spp. plants with a height between 3 and 5 cm and 4 to 6 leaves, the best treatments were T4, T8, T9, T10, T11, T12, T13, and T14, presenting a control percentage above 90%, 7 days after application. For Conyzaspp. plants with a plant development of 15 cm in height and 15 to 20 leaves, the highest control percentages and lowest regrowth percentages were with treatments T9, T13, and T14.