02772naa a2200217 a 450000100080000000500110000800800410001910000180006024500880007826000090016652020400017565000170221565000130223265000140224565000120225965000090227170000170228070000180229770000260231577302130234118879052012-02-29       2011    bl uuuu     u00u1 u    #d1 aTOLEDO, M. Z.  aPre-harvest desiccation with glyphosate and physiological quality of soybean seeds.  c2011  aPre-harvest desiccation of soybean plants with glyphosate is routinely conducted by seed producers, although it is not recommended for it may decrease seed physiological quality and, mainly, seedling development. This work had the objective of evaluating the effects of pre-harvest desiccation of soybean plants with glyphosate on the physiological quality of seeds harvested at two different times after the application. The experimental design was the completely randomized block, with four replications. Treatments consisted of the presence and absence of plant desiccation with glyphosate at R7 stage and harvest of seeds 7 and 14 days after the application. Moisture content of seeds was evaluated at physiological maturity and right after each harvest. Mechanical damage, viability, weight of 100 seeds, protein content and accumulation of glyphosate residues in seeds were determined after each harvest. Seed physiological quality was evaluated by tests of germination, accelerated aging, electrical conductivity, seedling length and seedling dry matter. Data was submitted to variance analysis and means were compared by the Tukey test (p?0.05), as a 2 x 2 factorial (presence and absence of desiccation x harvest times). Moisture content of soybean seeds harvested after desiccation of plants was 6.87% lower than moisture of seeds produced by non-desiccated plants 7 days after the application but no effects were found after 14 days. Accumulation of glyphosate residues in soybean seeds was higher whenever pre-harvest desiccation was conducted although residues were also found in seeds produced conventionally due to drift. Seed germination was decreased by pre-harvest desiccation as a result of increased number of abnormal seedlings. Glyphosate applied as desiccant also decreased seedling length, mainly primary root length. Later harvest decreased seed quality by slightly increasing mechanical damage and, thus, electrical conductivity, as well as protein content but not in interaction with pre-harvest desiccation.  aSeed quality  aSoybeans  aQualidade  aSemente  aSoja1 aTOMAZ, C. A.1 aCAVARIANI, C.1 aFRANCA NETO, J. de B.  tInformativo ABRATES, Brasília, DFgv. 21, n. 1, p. 223, abr. 2011. N. Especial, ref. 298. Edition of the Abstracts: 10th Conference of the International Society for Seed Science, Costa do Sauípe, Apr. 2011.