Sistemas de aplicação de subdoses de glifosato e regulador de crescimento em algodoeiro

• Autor(a) principal: Ferrari, João Vitor [UNESP]
• Data de Publicação: 2015
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/132236; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/13-11-2015/000854121.pdf
• topic: Algodão - Cultivo; Reguladores de crescimento; Hormese; Cotton growing

The cotton crop has featured on the world stage because employs advanced technology, represented by modern machinery and technicians with great field experience, high investments and the diversity of the plume use. The objective of this study was to evaluate the cotton cv. FMT 701 in function of application systems of glyphosate low dose and growth regulator. The experimental design was a randomized block in 6x2 factorial with four replications, totaling 48 plots with: a- number of glyphosate low dose applications (20 g a.e. (acid equivalent) ha -1 ): (zero, one, two, three, four and five), foliar applied respectively to 40; 40 and 50; 40, 50 and 60; 40, 50, 60, 70 and 40, 50, 60, 70 and 80 days after emergence of plants (d.a.e.); and b- managing of the growth regulator for foliar application (50 g a.i. (active ingredient - mepiquat chloride) ha -1 ) being split application form (3 days after application of glyphosate low dose) or only way at 70 d.a.e. (in plots that didn't receive a low dose); and without application. The cotton cultivar FMT 701 submitted to two applications glyphosate low dose has increased the height and leaf Mg concentration and greater number of bolls per plant and cotton seed yield when combined with mepiquat chloride. The use of the growth regulator provides increased stem diameter, leaf Mg and N concentration and SPAD chlorophyll content, and decreases the length of reproductive branches. Five applications of glyphosate low dose associated with the use of mepiquat chloride provide height plant reduction, yield and micronaire index in the cotton crop