Article

POTENCIAL FISIOLÓGICO DE SEMENTES DE SOJA DESSECADAS COM DIQUAT E PARAQUAT

Scientia agraria, ISSN 1983-2443, Vol. 10, Nº. 1, 2009, pags. 1-6 01/2009; 10(1). DOI: 10.5380/rsa.v10i1.12520
Source: OAI

ABSTRACT

O tipo, modo de ação e época em que o dessecante é aplicado na cultura da soja, são fatores que podem afetar a qualidade fisiológica das sementes. Porém, se a aplicação for realizada de maneira adequada, poderá ocorrer antecipação da colheita em alguns dias, obtendo sementes de maior qualidade. Assim, o presente trabalho teve como objetivo verificar o efeito da dessecação em pré-colheita no desempenho fisiológico de sementes de soja. O delineamento experimental foi de blocos ao acaso em esquema fatorial 3 x 4 (dessecantes x épocas) com quatro repetições. Os dessecantes foram Diquat e Paraquat, ambos na dose de 400 g i.a. ha-1, + testemunha (sem dessecação). As épocas de aplicação foram nos estádios R6.0, R7.1, R7.2 e R7.3. As sementes foram submetidas ao teste de germinação, primeira contagem da germinação, índice de velocidade de germinação, envelhecimento acelerado, teste de frio e condutividade elétrica. Todos os testes foram realizados no Laboratório de Análise e Tecnologia de Sementes da Universidade do Estado de Mato Grosso. A análise de variância foi realizada, sendo os dessecantes comparados pelo teste de Tukey (p<0,05). Apesar de terem proporcionado antecipação da colheita em apenas dois dias em relação à testemunha, a época mais favorável à dessecação, tanto com Diquat quanto Paraquat, é no estádio R7.3, sendo que os lotes dessecados com Paraquat apresentou melhor desempenho em alguns dos testes de qualidade avaliados.

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    • "C. Kappes et al. (2012) e-ISSN 1983-4063 -www.agro.ufg.br/pat -Pesq. Agropec. Trop., Goiânia, v. 42, n. 1, p. 9-18, jan./mar. 2012 obtidos por Kappes et al. (2009), ao verificarem que sementes de soja oriundas do tratamento testemunha foram as que apresentaram menores valores de condutividade , sendo, porém, ainda caracterizadas como de baixa qualidade fisiológica, conforme os valores sugeridos por Vieira (1994). Lacerda et al. (2005) não constataram efeito dos dessecantes paraquat (400 g ha"
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