Section 725.239 - Use of specific microorganisms in activities conducted outside a structure(a)Bradyrhizobium japonicum. To qualify for an exemption under this section, all of the following conditions must be met for a test involving Bradyrhizobium japonicum:(1)Characteristics of recipient microorganism. The recipient microorganism is limited to strains of Bradyrhizobium japonicum.(2)Modification of traits.(i) The introduced genetic material must meet the criteria for poorly mobilizable listed in § 725.421(c) .(ii) The introduced genetic material must consist only of the following components: (A) The structural gene(s) of interest, which have the following limitations: (1) For structural genes encoding marker sequences, the gene is limited to the aadH gene, which confers resistance to the antibiotics streptomycin and spectinomycin.(2) For traits other than antibiotic resistance, the structural gene must be limited to the genera Bradyrhizobium and Rhizobium.(B) The regulatory sequences permitting the expression of solely the gene(s) of interest.(C) Associated nucleotide sequences needed to move genetic material, including linkers, homopolymers, adaptors, transposons, insertion sequences, and restriction enzyme sites.(D) The vector nucleotide sequences needed for vector transfer.(E) The vector nucleotide sequences needed for vector maintenance.(3)Limitations on exposure.(i) The test site area must be no more than 10 terrestrial acres.(ii) The technically qualified individual must select appropriate methods to limit the dissemination of modified Bradyrhizobium japonicum.(b)Rhizobium meliloti. To qualify for an exemption under this section, all of the following conditions must be met for a test involving Rhizobium meliloti:(1)Characteristics of recipient microorganism. The recipient microorganism is limited to strains of Rhizobium meliloti.(2)Modification of traits.(i) The introduced genetic material must meet the criteria for poorly mobilizable listed in § 725.421(c) of this part.(ii) The introduced genetic material must consist only of the following components: (A) The structural gene(s) of interest, which have the following limitations:(1) For structural genes encoding marker sequences, the gene is limited to the aadH gene, which confers resistance to the antibiotics streptomycin and spectinomycin.(2) For traits other than antibiotic resistance, the structural gene must be limited to the genera Bradyrhizobium and Rhizobium.(B) The regulatory sequences permitting the expression of solely the gene(s) of interest.(C) Associated nucleotide sequences needed to move genetic material, including linkers, homopolymers, adaptors, transposons, insertion sequences, and restriction enzyme sites.(D) The vector nucleotide sequences needed for vector transfer.(E) The vector nucleotide sequences needed for vector maintenance.(3)Limitations on exposure.(i) The test site area must be no more than 10 terrestrial acres.(ii) The technically qualified individual must select appropriate methods to limit the dissemination of modified Rhizobium meliloti.