## Plant Pest Risk Assessment for DAS-68416-4 Soybean

Contents

A. Introduction 1

B. Development of DAS-68416-4 he rbicide tolera nt soybean 2

C. Description of the modification 5

D. Potential for DAS-68416-4 to have al tered disease and pest susceptibilities 6

E. Potential for effect on non-target organisms, including those benefici al to agriculture 6

F. Potential for enhanced w eediness or invasiveness 7

G. Potential of DAS-68416-4 to impact the w eediness of other plants with which it can

interbreed 8

H. Potential changes to agricultu ral or cultivation practices 9

I. Potential impacts from tran sfer of genetic information to organisms with which DAS68416-4 cannot interbreed 9

J. Conclusion 10

K. References 11Plant Pest Risk Assessment for DAS-68416-4 Soybean

1 A. Introduction

Dow AgroSciences LLC (DAS) has petitione d APHIS (APHIS number 09-349-01p) for a determination that genetically engineered (GE) soybean ( Glycine max ) event DAS-68416-4 is unlikely to pose a plant pest risk (DAS 2010) and, therefore, should no longer be a regulated article under APHIS’ 7 Code of Federal Regu lations (CFR) part 340. APHIS administers 7 CFR part 340 under the authority of the plant pe st provisions of the Pl ant Protection Act of

2000 1 . This plant pest risk assessment was conducted to determine whether DAS-68416-4 soybean is unlikely to pose a plant pest risk.

DAS-68416-4 was produced by transformation of cotyledonary node explants of soybean ( Glycine max cv Maverick) with Agrobacterium tumefaciens . Because A. tumefaciens is a plant pest and some of the re gulatory sequences (promoter from cassava vein mosaic virus

and terminator from A. tumefaciens ) used to facilitate expression of the genes in soybean were derived from plant pests, this soybean has b een considered a regulated article under APHIS regulations at 7 CFR part 340.

Potential impacts considered in this Plant Pest Risk Assessment are those that pertain to the use of DAS-68416-4 and its progeny in the abse nce of confinement. APHIS regulation 7 CFR 340.6(c) specifies the information needed for consideration in a pe tition for nonregulated status. APHIS will evaluate information submitted by the applicant, in addition to current literature, related to plant pest risk characteri stics, disease and pest susceptibilities, expression of the gene product, new enzymes, or changes to plant metabolism, weediness of the regulated article, any impacts on the weediness of any other plant with which it can interbreed, potential changes to agricultural or cultiv ation practices, potent ial effects to non-target organisms, and transfer of genetic information to organisms w ith which it cannot interb reed, to determine if DAS-68416-4 is unlikely to pose a plant pest risk . If APHIS determines that a GE organism is not a plant pest risk, th en APHIS has no regulatory aut hority over that organism.

1 Section 403 (14) of the Plant Protection Act (7USC Sec 7702(14) defines plant pest as: “Plant Pest - The term “plant pest” means any living stage of any of the following that can directly or indirectly injure, cause damage to, or cause disease in any plant or plant product: (A) A protozoan. (B) A nonhuman animal. (C) A parasitic plant. (D) A bacterium. (E) A fungus. (F) A virus or viroid. (G) An infectious agent or other pathogen. (H) Any article similar to or allied with any of the articles specified in the preceding subparagraphs.”Plant Pest Risk Assessment for DAS-68416-4 Soybean

2 B. Development of DAS-68416-4 herbicide tolerant 2 soybean

In the U.S. soybean was grown on 75.0 milli on acres in 2011 (Figure 1; USDA NASS 2011a) with a value of $29.6 billion in 2008/2009 (USDA ERS 2011a). Growers select soybean lines adapted to the different environmental and clim atic features, operator’s education, weed and disease pressures, cost of seed and other inputs, technology fees, human safety, ease and flexibility of the productions system and marketing reasons (USDA ERS 2002; Brookes 2011).

Figure 1. Soybean production areas in the U.S. (USDA NASS 2011b).

The presence of weeds in soybean fields cancause greater production losses than either insects or diseases (Gibson 2005; Oerke 2006) . Before the development of effective

herbicides for the selective cont rol of weeds in soyb eans in the early 1960’s , cultural practices including tillage, use of weed free seed, row sp acing and crop rotation were the only ways to control weeds (Wax 1973). By 1987, over 30 herb icides were being used on soybeans (Jordan 1987). With the 1996 commercial introduction an d rapid adoption of glyphosate tolerant soybeans, a major change in herbicide usage occurred with an increasing use of glyphosate

concurrent with the increased planting of glyphosate tolerant s oybeans and a decrease in use of other soybean herbicides (Figure 2; NRC 2010; Young 2006). Consequently, the diversity of herbicides used for weed management ha s declined in soybean (Table 1; Young 2006) resulting in weed species shif ts (Johnson 2009). Determinati on of nonregulated status for

2 The applicant has described DAS-68416-4 soybean as “herbicide tolerant” and historically APHIS has also referred to GE plants with diminished herbic ide sensitivity as “herbicide tolerant.” However, the phenotype would fall under the Weed Science Societ y of America’s (WSSA) de finition of “herbicide resistance” since DAS-68416-4 has an inherited ability to survive and reproduce fo llowing exposure to a dose of herbicide normally lethal to the wild type variety (WSSA 1998). By the WSSA definition, “resistance [to an herbicid e] may be naturally occurring or indu ced by such techniques as genetic engineering or selection of variants produced by tissue culture or mutagenesis.” Herbicide tolerance, by the WSSA definition, only applies to plant species with an “inherent ability” to survive and reproduce

after herbicide treatment.Plant Pest Risk Assessment for DAS-68416-4 Soybean

3 DAS-68416-4 soybean would provide soybean gr owers with additional options for the postemergent control of both broadleaf and grass weed s. The integration of other herbicides with different modes of action with glyphosate has been encouraged to improve the duration of weed control, to enhance control of glyphosat e tolerant weeds, to reduce the risk of developing glyphosate resistant weeds and to control glyphosate-resistant weeds (WSSA 2010). This soybean product would also prov ide another tool to use against increased incidence of weed species that are more to lerant to glyphosate ( NRC 2010; WSSA 2010).

Figure 2. Percent acreage of genetical ly engineered crops in the U.S. (USDA ERS 2011b).

Table 1. Percent of U.S. Soybean Acre s Treated with Herbicides in 1990, 1995, 2001 and 2006 (USDA NASS 2010).

Herbicide Percent Soybean Acres Treated

1990 1995 2001 2006
2,4 D 3 10 4 2,4-D Dimethlyl salt

-- -- -- 3 Acetic acid (2,4 D) -- -- -- 7
2,4-DB -- 1 -- --

Acifluorfen

-- -- 3

-- Alachlor 13 4 --

-- Bentazon 16 12 1

-- Chloramben 1

-- -- -- Chlorimuron, ethyl 20 16 5 4

Clethodim

-- 5 4 3

Clomazone 7 4 Cloransulam, methyl

-- -- 5 1

Dimethenamid

-- 1

-- -- Ethalfluralin 5 1

-- -- Fenoxaprop
-- 6 3

--Plant Pest Risk Assessment for DAS-68416-4 Soybean

4 Herbicide Percent Soybean Acres Treated

1990 1995 2001 2006 Fluazifop, P, butyl 6 10 3 1

Flumetsulam -- 2 -- -- Flumiclorac, pentyl

-- -- -- 1

Fomesafen 2 4 7 2 Glyphosate 5 21 73 92

Imazamox -- -- 5 -- Imazaquin 16 15 2 1 Imazethapyr 11 44 9 3

Lactofen 1 5 1 --

Linuron 6 2

-- -- Metolachlor 10 7
-- -- Metribuzin 19 11 2 2
Paraquat 2 2 -- 1

Pendimethalin 14 26 10 3 Quizalofop 3 6 --

-- S-Metolachlor -- -- -- 1 Sethoxydim 4 7 1

-- Sulfentrazone -- -- 5 1

Sulfosate

-- -- 3 1

Thifensulfuron 4 12 2 1 Tribenuron, methyl

-- -- -- 1

Trifluralin 37 20 7 2

DAS-68416-4 soybean is a GE soybean line that has been developed to increase tolerance to the herbicides 2,4-D and glufosinate. The in troduced genetic material results in the production of aryloxyalkanoate dioxygenase-12 (AAD-12) that degrades the herbicide 2,4-D into herbicidally-i nactive 2,4-dichlorophenol (Mü ller 1999; Westendorf 2002 and 2003; Wright 2010a) and phosphinothricin acetyltransferase (P AT) that metabolizes the L-isomer of glufosinate into non-phytotoxi c N-acetyl-L-glufosinate (2 -acetamido-4-methylphosphinicobutanoic acid) (OECD 2002). If given non-regulated status, DAS-68416-4 soybean would be the first soybean variety with increased tolerance to both 2,4- D and glufosinate.

2,4-D (2,4-dichlorophenoxyacetic acid) is an herbicide in the phenoxy or phenoxyacetic acid family used for selective control of broadl eaf weeds since the mid-1940s in over 600 products in agricultural and residential applications (USEPA 2005). The mode of action of 2,4-D for broadleaf plants is unclear, but it is belie ved to function as a plant growth regulator 3 with synthetic auxin hormone-like properties. Wh en applied as an herbicide 2,4-D causes abnormal cell division and growth lead ing to plant injury and death.

Glufosinate (phosphinothricin ; DL-homoalanin-4-yl(methyl ) phosphinic acid) is a nonselective foliar herbicide used for pre-plant a nd post-emergent control of broadleaf plants and

3 Plant Growth Regulators are synthetic plant hormones that regul ate cellular processes, plant gr owth and development. Auxin compounds represent a class of hormones that along with other plant hormones determine patterns of plant development.Plant Pest Risk Assessment for DAS-68416-4 Soybean

5 annual and perennial grasses (OECD 2002; USEP A 2008). Glufosinate acts by inhibiting the enzyme glutamine synthetase, which leads to poisoning in plants because of the overproduction of ammonia. Glufosinate was first registered by EPA for use in 2000 as a

non-selective foliar he rbicide that is used for pre-plant a nd post-emergent control of broadleaf weeds (USEPA 2008). EPA registration author izes use on many crops including; apples, berries, canola, corn, cotton, currants, grapes, gr ass grown for seed, potatoes, rice, soybeans, sugar beets, and tree nuts and in non-crop areas including lawns and resi dential areas (USEPA 2008). APHIS reached a determination of nonre gulated status for the first soybean line genetically engineered with th e glufosinate-tolera nce trait in 1996 (USDA APHIS 2011).

C. Description of the modification

Soybean DAS-68416-4 was produced by transformation using disarmed Agrobacterium tumefaciens (DAS 2010). Soybean (cultivar Maverick) cotyledonary nodes were infected with Agrobacterium strain EHA101 (Hood 1986) cont aining plasmid pDAB4468. Plants containing the introduced DNA were selected based on growth in the present of glufosinate (DAS 2010, p. 20).

The plasmid pDAB4468 contained two gene expression cassettes fl anked by T-DNA border sequences from the Agrobacterium Ti-plasmid (DAS 2010, p. 21).

Aryloxyalkanoate dioxygenase

 RB7 MAR (Matrix attachment region 4 ) from the Nicotiana tabacum rb-7-5A gene (Hall 1991).

 Polyubiquitin promoter (AtUbi10) from Arabidopsis thaliana (Norris 1993).

 aad-12 gene from Delftia acidovorans encoding aryloxyalkanoate dioxygenase12 (AAD-12) that degrades 2,4-D into herb icidally-inactive 2,4-dichlorophenol (DCP) (Wright 2010a and 2010b). The native gene was modified for better expression in plants (DAS 2010). Delftia acidovorans is a bacterium commonly found in the environment (Wen 1999) has a history of safe use.

 3’ untranslated transcriptional terminator and polyadenylation s ite of open reading frame 23 (AtuORF23) from Agrobacterium tumefaciens pTi15955 (Barker 1983).

Phosphinothricin N-acetyltransferase (PAT)

 Promoter and the 5’UTR (CsVMV) from the cassava vein mosaic virus (Verdagurer 1996).

4 Chromosomal DNA is organized into looped domains through inter actions with and attachment to a proteinaceous structure, called the nuclear scaffold, nuclear scaffold, or matrix. Speci fic chromosomal DNA sequences are thought to contain attachment regions that anchor the DNA to the matrix . Attachment regions may increase leve ls of expression, reduce transformant-totransformant variation of expression, st abilize transgene expression and minimize tr ansgene silencing (Abranches 2005; Allen 2000; Spiker 1996).Plant Pest Risk Assessment for DAS-68416-4 Soybean

6  pat (phosphinothricin N-acetyltransferase) gene from Streptomyces viridochromogenes inactivates the herbicide gl ufosinate (Wohlleben 1988). The native gene was modified for bette r expression in plants (DAS 2010).

 Transcriptional terminator and polyade nylation site of open reading frame 1 (AtuORF1) of Agrobacterium tumefaciens pTi15955 (Barker 1983).

Data from Southern blot an alysis demonstrate that DAS-68416-4 soybean contains (DAS 2010, tables 2 & 3): (1) a single copy of RB7 (DAS 2010, figures 24 & 26), AtUbi10 (DAS 2010, figures 13, 14, 25 & 26) add-12 (DAS 2010, figures 8, 9, 10, 11), AtuORF23 (DAS 2010, figures 13 & 15); and (2) a single c opy of CsVMV (DAS 2010, figures 21 & 22), pat (DAS 2010, figures 16, 17, 18, 19, 20 & 21), AtuORF1 (DAS 2010, figures 21 & 23).

D. Potential for DAS-68416-4 to have alte red disease and pest susceptibilities

APHIS assessed whether DAS-68416-4 soybean is lik ely to have signific antly altered disease and pest susceptibility. This assessment enco mpassed consideration of the introduced trait and disease and pest sus ceptibility data from DAS-68416-4 soybean field trials.

DAS-68416-4 soybean has been field tested in the U.S. since 2008. Agronomic data was

collected in 2008 and 2009 in 27 lo cations that represented a di verse range of environmental conditions where DAS-68416-4 soybean is expected to be grown. No statistically significant

differences were observed for st and count, emergence, seedling vigor, days to flower, lodging, disease incidence, insect damage and yiel d (DAS 2010, Section VII-B , VII-C, VII-D). No qualitative or quantitative obser vations indicated any biologic ally meaningful differences

from control lines or differences outside the range of convent ional soybean norms.

The descriptions of the introduced genetic elem ents, expression of the gene products and their functions of DAS-68416-4 soybean have been summarized above. The Agrobacterium transformed plants used in the generation of DAS-68416-4 soybean were treated with an

antibiotic to kill the Agrobacterium cells. Furthermore, DNA se quences derived from plant pests that were incorporated in DAS-68416-4 do not result in the pr oduction of infectious agents or disease symptoms in plants, and so it is unlikely that DAS-68416-4 soybean could pose a plant pest risk.

Given the interactions between the environment, the genetic b ackgrounds of the cultivars used and some inherent genetic variability within soybean varieties, APHIS concludes that these results do not indicate an increased pest risk. Expression of AAD-12 and PAT in DAS68416-4 soybean is not expected to cause plant disease or influence susceptibility of DAS68416-4 soybean or its progeny to di seases or other pests.

E. Potential for effect on non-target organis ms, including those bene ficial to agriculture

There is no reason to believe th at deleterious effects or si gnificant impacts on non-target organisms, including beneficial organisms, woul d result from the cultivation of DAS-68416-4. Field observations of DAS-68416-4 soybean (DAS 2010, Section VII-B) revealed no negativePlant Pest Risk Assessment for DAS-68416-4 Soybean

7 effects on non-target organisms, suggesti ng that the production of the ADD-12 and PAT proteins in the plant tissues ar e not toxic to organisms. The introduced genetic material does not result in the producti on of novel proteins, enzymes, or metabolites in the plant that are known to have toxic properties. The lack of known toxicity of ADD-12 and PAT suggests no potential for deleterious effect s on beneficial organisms such as bees and earthworms. The use of 2,4-D and glufosinate herbicides in the cultivation of DAS-68416-4 soybean or its offspring is regulated by EPA under its existing regulations for the registration of pesticide use. EPA considers the impacts on the e nvironment, including effects on non-target organisms in establishing application rates a nd residue tolerances for herbicides, including 2,4-D and glufosinate tolerant lines (USEPA 1997; USEPA 2005). APHIS has not identified any other potential mechanisms for dele terious effects on non-target organisms.

F. Potential for enhanced weediness or invasiveness

APHIS assessed whether DAS-68416-4 soybean is a ny more likely to become a weed than the non-transgenic recipient soybean line, or other soybean currently cultivated. The assessment encompasses consideration of the basic biol ogy of soybean and an evaluation of unique characteristics of DAS-68416-4 soybean.

Weediness for the purposes of this part of the plant pest risk assessment is an attribute, which causes a crop to act as a weed due to the a ddition of genes, in comparison to the non-GE comparator (parental line Mave rick). If the fitness of DAS-68416-4 soybean improves in natural or agricultural ecosystems due to the inserted DNA, the potential for weediness could increase. The following analysis of the in serted DNA is intended to document that DAS68416-4 soybean has a negligible like lihood of increased weediness.

In the U.S., soybean is not listed as a weed in the major weed references (Crockett 1977; Holm 1979; Muenscher 1980) nor is it designate d as noxious weed by the federal government (USDA NRCS 2012a). Soybean does not possess a ny of the attributes commonly associated with weeds (Baker 1965), such as long persistence of seed in the soil, the ability to disperse, invade, and become a dominant species in new or diverse landscapes, or the ability to compete well with native vegetation. Furthermore, matu re soybean seeds have no innate dormancy, are sensitive to cold, are not expected to survive in freezing winter conditions and do not reproduce vegetatively (Hermann 1962; OECD 2000; Padgette 1996; Raper Jr.1987).

In 2008 and 2009, Dow conducted field trials to evaluate phenot ypic characteristics comparing DAS-68416-4 soybean with the non-t ransgenic soybean variety “Maverick.” Agronomic performance characteristics, includi ng stand count, emergence, seedling vigor, days to flower, days to maturity, plant height , lodging, and shattering were evaluated. There were no significant differences except th at DAS-68416-4 took one less day (128.4 compared to 129.3) to reach seed maturation and had a sl ightly lower seed size (3.5%) (DAS 2010, page 85). However this lower seed size did not aff ect yield. Based on analysis of data on all these parameters, soybean DAS-68416-4 soybean is unlikel y to pose any more of a plant pest risk

from weediness than the conventiona l soybean from which it was derived.Plant Pest Risk Assessment for DAS-68416-4 Soybean

8 APHIS also assessed whether DAS-68416-4 soybean is any more likely to become a weed than its parental comparator line “Maverick” or other soybean varieties currently under cultivation. The assessment encompasses consid eration of the basic biology of soybean and an evaluation of the unique characteristics of DAS-68416-4 soybean under field conditions. To increase weediness of the soybean plant ther e would have to be selection pressure on the line (Tiedge 1989). Because 2,4-D or glufosinate will not affect the survival of DAS-68416-4 soybean and because soybean is not itself weedy, this type of selection pressure does not now and is unlikely ever to exist.

Results on growth characteristics, seed produc tion and germination indicate that DAS-68416- 4 soybean is not significantly different from its comparators (DAS 2010, pages 79 - 85). There is no indication that DAS-68416-4 soybean possesses a selective a dvantage that would

result in increased weediness. DAS-68416-4 soybean lacks the abil ity to persist as a troublesome weed, and there would be no signi ficant impact on current weed management practices for soybean cultivation.

G. Potential of DAS-68416-4 to impact the weed iness of other plants with which it can

interbreed

The genus Glycine , a member of the Fabaceae (= Leguminosae or pea family), consists of two subgenera, soja and glycine (OECD 2000; USDA NRCS 2012b). Perennial species in the subgenus glycine do not occur in the U.S. (USDA NRCS 2012b), except in the U.S. territories in the South Pacific (Hymowitz 1987). The subgenus soja consists of thr ee annual species: G. soja Sieb. and Zucc., the w ild form of soybean; G. gracilis Skvortz., the weedy form of soybean; and G. max (L.) Merr., the cultivated soybean. G. soja and G. max do not occur naturally in the U.S. (Hermann 1962; Hymow itz 1987; USDA NRCS 2012b). Hybrids from crosses between the subspecies have generally been sterile, and further progeny have only been obtained with extreme difficulty (OECD 2000).

Cultivated soybean is highly self-pollinating (A hrent 1994). When soybean plants are grown directly adjacent to other soybean plans, the amount of natural cross pollination has generally been found to be 0.5 - 1 pe rcent (Fehr 1980; OECD 2000), although higher values (2.5 percent) occur in some varie ties (Abud 2007). Outcrossing can be reduced to 0 – 0.01 percent with a separation distance of 10 meters (Abud 2007).

The cultivated soybean, G. max , lacks sexually compatible wild relatives in the U.S. and its territories. Consequently, there is no potential fo r gene flow from cultivated soybean plants to wild relatives in the U.S. Therefore, it is not likely that gene flow and introgression will occur between DAS-68416-4 soybean and other species of soybean. APHIS has determined that any adverse consequences of gene flow from DAS-68416-4 soybean to wild or weedy species in the U.S. are highly unlikely.Plant Pest Risk Assessment for DAS-68416-4 Soybean

9 H. Potential changes to agricul tural or cultivation practices

None of the management practi ces currently employed for soyb ean production is expected to change if DAS-68416-4 soybean is determined to be no longer subjec t to the re gulatory requirements of 7 CFR part 340 or the plant pe st provisions of the Pl ant Protection Act. DAS’s (2010) studies demonstrate that the agronomic characterist ics and cultivation practices employed when growing DAS-68416-4 soybean are essentially indistinguishable from practices used to grow other soybean varieties, in cluding other herbicide-tolerant varieties (DAS 2010, Section IX-E). The geographic range or seasonality of soybean cultivation is not expected to change to accommodate the cu ltivation of DAS-68416-4 soybean (DAS 2010). DAS-68416-4 soybean is comparable to currently available soybean varieties in terms of

resistance to insects and di sease (DAS 2010, Section VII B.). Therefore, no changes are expected for insect and disease control practices with DAS-68416-4 soybean. Because agricultural and cultivation pract ices would not be significant ly different than that of conventional soybean, APHIS does not foresee cha nges in on insects or diseases damage or control measures employed due to agricultura l or cultivation pr actices with DAS-68416-4 soybean.

I. Potential impacts from tr ansfer of genetic information to organisms with which DAS68416-4 cannot interbreed

APHIS examined the potential for the new ge netic material inserted into DAS-68416-4 soybean to be horizontally transferred to other organisms without sexual reproduction and whether such an event could lead directly or indi rectly to disease, damage, injury or harm to plants. Horizontal gene transfer and expression of DNA from a plant species to other species is highly unlikely to occur ba sed on the following reasons.

The horizontal gene transfer (HGT) between unrelated organisms is one of the most intensively studied fields of science. HGT and expression of DNA from a plant species to bacteria or animal species is unlikely to occur (Keese 2008).

1. Many genomes (or parts thereof) from bacteria that are closely associated with plants have been sequenced, including Agrobacterium and Rhizobium (Kaneko 2000; Kaneko 2002; Wood 2001). There is no evidence that these organisms contain genes derived from plants. Therefore, the likelihood of any impact or new HGT that is not already capable of taking place in the soil is extremely unlikely.

2. No evidence has been identified for any mechanism by which soybean genes could be transferred to humans or animals, or any evid ence that such gene transfer has occurred for any plant species during evolutionary history, despite animals and humans eating large quantities of plant DNA. In cases wher e review of sequence data implied that HGT occurred, these events are inferred to occur on an evolutionary time scale on the order of millions of years (Brown 2003; Koonin 2001).

3. Transgene DNA promoters and coding sequences are optimized for plant expression, not prokaryotic bacterial expression. Thus, even if HGT occurred, proteins corresponding to the transgenes are not likely to be produced.Plant Pest Risk Assessment for DAS-68416-4 Soybean

10 4. FDA has evaluated HGT from the use of an tibiotic resistance marker genes, and

concluded that the likelihood of transfer of antibiotic resistance genes from plant genomes to microorganisms in the gastrointestin al tract of humans or animals, or in the environment, is extremely unlikely (FDA 1998).

Therefore, APHIS concludes that HGT is highly unlikely to occur and thus poses no significant plant pest risk.

J. Conclusion

APHIS has prepared this plant pest risk a ssessment in order to determine if DAS-68416-4 soybean is likely to pose a plant pest risk. Based on the information provided by the applicant and the lack of atypical responses to disease or plant pests in the field, the lack of weedy characteristics of the DAS-68416-4 soybean or othe r plants with which it can interbreed, that there are no anticipated changes to agricultural or cultivation practices that would result in increased diseases or pests, th e lack of effects on non-targets or beneficial organisms in the agro-ecosystem, the lack of any indirect e ffects on other agricu ltural products and the unlikelihood of horizontal gene transfer, APHIS has concluded that soybean DAS-68416-4 soybean is highly unlikely to pose a plant pest risk.Plant Pest Risk Assessment for DAS-68416-4 Soybean

11 K. References

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