Growth inhibitors are about as important as growth stimulators. Some plant residues like seaweed, kudsu, and yucca are believed to be good sources of some biostimulants. Processed humic acid is marketed with some claims of stimulation. The on going debate about whether compost is more valuable than uncomposted materials involves the possibility that some microbes produce biostimulants in the composting process. There is some reason to expect that use of materials by soil application that contain biostimulants can often be a best management practice to interact favorably with other such products to improve the efficiency of crop production.
More research is needed.
Does not include commercial fertilizers, agricultural minerals, soil amendments, or manure's. Biotics are all materials for which claims are made relating to organisms, enzymes, or organism by- products. Several different types of products are included in this list. Only those which are considered as biostimulants are the subject of this paper. This brief discussion is an introduction only to a broad field of study which has resulted in some but not enormous technologies.