Moisture content and storage temperature on the physical and physiological quality of soybean seeds treated with phytosanitary products

ABSTRACT:

Phytosanitary seed treatment (ST) of soybeans is fundamental to guaranteeing the establishment of the crop’s stand, for control of diseases and pests, provided it is conducted correctly. A key factor in this process is the moisture content of the soybean seeds at the time of ST, which is also related to their preservation during storage. The aim of this study was to assess how the moisture content of the seeds at the moment of ST affects their physical and physiological quality during storage at different temperatures, with the aim of identifying the ideal moisture content values for ST. Seeds from the same lot were adjusted to moisture contents of 7%, 9%, 11%, 13% and 15%, treated with phytosanitary products and stored at temperatures of 10 °C, 20 °C, 30 °C and alternating 20-30 °C. Physical and physiological quality was assessed after 0, 45, 90 and 135 days, by the germination, emergence, tetrazolium and moisture content tests. Storage at 10 °C was the most efficient for maintaining quality, while higher temperatures accelerated deterioration. Seeds with a moisture content higher than 13% show greater loss of quality, whereas seeds with less than 9% moisture are more susceptible to mechanical damage during ST processing and imbibitional injury. Moisture content of 11% is the most recommended for soybean ST.

Index Terms:
Glycine max L.; industrial seed treatment; seed safety; water content