Biological Seed Treatments

Abstract

Bacteria and fungi are both used in biological seed treatments. While all have potential uses, some organisms are more widely and successfully used than others. Shelf life is an important consideration. For this reason, organisms that lack cell walls are more difficult to use than ones with long-lasting spores. Bacillus and Trichoderma are both widely effective, have good shelf life, and are frequently used. However, Rhizobiacae lack cell walls, which is a limitation; they are widely used because their symbiosis with legumes facilitates nitrogen fixation which is an important factor that provides economic, agricultural and environmental sustainability. For all organisms, proper formulation is critical for success; this is especially true for Rhizobiacae and other gram-negative bacteria. There are several specialized processes to deliver microbial agents or to enhance their biological activity, such as solid matrix priming and hydroseeding. Biorational chemicals derived from microorganisms are also frequently used. Both living organisms and biorationals provide benefits to plant agriculture. They can control diseases and increase resistance to abiotic stresses such as drought, temperature, salt, and flooding. They also can enhance mineral nutrition and photosynthesis. For these applications, the most effective ones colonize roots internally and provide season-long benefits. These endophytes induce systemic changes in plants’ gene expression and encoding of proteins.

Evaluation of Industrial Hemp Seed Treatments for Management of Damping-Off for Enhanced Stand Establishment

“…Organically approved treatments would be ideal so that they could be used in both conventional and organic production systems. Significant advances were made in recent decades in the application of biopesticides as seed treatments that have resulted in increased efficacy and more consistent disease control [19].…”