Study of the Effect of Shade Cloth Cover on Quality of Soybean Seeds (Glycine max (L.) Merr.) Stored in Plastic Bags.

Abstract

Storage of grains and oilseeds in plastic bags in Argentina has expanded steadily in the last years; indeed, in the 2007/08 crop year 35 million tons (t) have been stored using this system. The use of this type of storage spread mainly among small-scale producers, extending to farming cooperatives, middlemen, and industries. Later, several high-quality seed companies adopted storage in plastic bags and obtained diverse results; a number of specific problems remain unsolved. The aim of this work was to study the effect of shadow cloth cover on the quality of soybeans stored in plastic bags, by comparing different cultivars and grains with different moisture content. Several soybean cultivars with 10.8% (dry) and 15.7 % (moist) grain moisture content (m.c.) were used. In July 2003 shadow cloth was placed longitudinally on half of the bags. Grain samples were taken from the top, middle, and bottom sectors of both parts (covered and not covered by the shadow cloth) of the bags, every 60 days up to December 2003. The shadow cloth cover was effective in maintaining quality of moist seeds until October, without variation in seed germination (SG). Quality of seeds under the shadow cloth cover was also high in December, but SG decreased to 80%, whereas seeds exposed to ambient conditions (without cover) only reached 60% of SG. In dry seeds, no significant differences were observed between seeds covered by the shadow cloth and seeds stored in bags exposed to ambient conditions.