Bt Brinjal The scope and adequacy of the GEAC environmental risk assessment

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48 Bt Brinjal: The GEAC environmental risk assessmentcontrol for brinjal. This is a complex question that will require some effort to gain clarity.Finding 23. The agronomic performance and efficacy experiments for hybrid Bt brinjal are designed for large-scalecommercial brinjal production systems, and do not reflect the production systems used by small-scale resource-poorfarmers. The data are probably appropriate for about 4% of brinjal production in India.The multi-site trials (MST, Dossier, volume 6) and the large-scale trials (LST, Supplemental Materials) are not designed toreflect the diversity of production systems in India. Specifically, these experiments mimic the production systems of large-scalecommercial brinjal producers who already purchase hybrid seed and do not reflect the production systems used by small-scaleresource-poor farmers.A. No trials were conducted where the most brinjal is grown. West Bengal, Orissa, and Bihar produce 61% of the brinjalin India. Bt brinjal has been banned from these states, but because agronomic performance varies with geographic locality,the results from the MST and LST can apply at most to 39% of the brinjal production in India.B. Comparisons are made among a Bt brinjal hybrid, a genetically similar non-Bt brinjal hybrid, a commercial hybrid withsimilar fruit morphology, and a local variety with similar fruit morphology (in year 2 of the MST). The local variety used inthe MST experiments is not necessarily the most common or preferred local variety. Thus, the brinjal varieties are often notsuitable for estimating profitability of small-scale resource poor farmers, who grow local varieties.C. Agricultural inputs in the MST and LST are those recommended for large-scale commercial production. Small-scaleresource-poor farmers typically use saved seed, manures and composts for fertilisers and locally produced insecticides andhand-rouging for pest control. Thus, the production system used are appropriate for large-scale commercial farmers, but notfor small-scale resource-poor farmers. On average, about 10% of the brinjal producers outside of West Bengal, Orissa andBihar are large-scale commercial producers (APEDA 2009). So the MST and LST data are appropriate only for about 4% ofthe brinjal producers in India; these are producers that are outside these states and produce on large-scale (100 x 0.39 x 0.10).D. The LST field trials were probably conducted on soils representative of intensive, large-scale, commercial production.Availability of potash, a critical macro nutrient for brinjal depends on many factors. Under intensive, large-scale, commercialbrinjal production, soil organic matter content (SOM) can drop to 0.3-0.4%. When SOM is this low, brinjal yield potentialdepends primarily on the levels of external input. SOM for many small-scale resource-poor farmers is typically muchhigher than this, and under these conditions, brinjal yield is a complicated function of soil quality and external inputs.Consequently, the agronomic yield data probably do not represent production systems of small-scale resource-poor farmers.Although soil pH and SOM content are not reported for the LST field trials, the trials were conducted on experimental farmsthat were likely to reflect standard, commercial production systemswith low SOM.Figure 3. Measure of yield gap between yields observedE. Brinjal yield loss from BFSB is different for large-scale in experimental trials and average yields on farm.commercial producers and small-scale resource-poor farmers (Table1 in Context and Need section). The MST and LST assess yieldloss the way large-scale commercial producers would assess it.Small-scale resource-poor farmers sell partially infested fruits on themarket and consume the unsold remainder. Less damaged fruitscan be marketed at a good price because BFSB damage symptomsindicate to some consumers that reduced amounts of pesticideshave been used.F. A critical economic value of small-scale resource-poorfarmers is not considered. For these farmers, brinjal shelf life iscritical for determining the economic value of the brinjal crop.Under small-scale production practices, brinjal typically has amuch longer shelf life than brinjal produced under large-scaleproduction practices. The longer shelf life means brinjal retains its
Socioeconomic Analysis 49economic value for a longer period of time, andsmall-scale resource-poor farmers may distributetheir supply over time to obtain higher and/or steadier income. In this way, brinjal isessential for the economic security of small-scaleresource-poor farmers.Large-scale commercial growers compriseabout 10% of all brinjal producers outside of themain production areas in West Bengal, Orissa,and Bihar. Therefore, the profitability analysispresented by EC-II is appropriate for only about4% of all the brinjal producers in India (0.1 x(1 – 0.61)).Despite all of the limitations, a narrowutilitarian may still suggest that the MST andLST data can be used to estimate profitabilityof Bt brinjal for farmers in India. This is awidely-shared perspective and is not as simpleto refute as the previous argument might makeevident. For example, limitation A is alreadytaken into account in the calculation in theprevious paragraph, and Table 1 (Context andNeed section) indicates that limitation E mightbe addressed by discounting the MST and LSTresults by 2/3rds. In a similar way, it couldbe argued that limitations B, C, and D can beaddressed by discounting the MST and LSTby some additional unknown X% to take intoaccount those data limitations. For lack of abetter value, a narrow utilitarian might perhapssuggest that 50% would suffice. Therefore, theprofitability for small-scale resource-poor farmersmight be 1/6 th that estimated by EC-II. However,this calculation does not take into accountlimitation F or the issue of yield gaps, which iscovered next.Finding 24. Yield gaps are prevalentbetween experimentally estimated yieldand average farmer yield. The yield benefitof hybrid Bt brinjal estimated from thecontrolled MST and LST experiments shouldbe multiplied by 0.54 to estimate the yieldbenefit for the average large-scale commercialfarmer. This also reduces the estimatedbenefit to small-scale resource-poor framers.Box 12Brinjal Yield Gap: Overestimation of Yield Benefit of Bt BrinjalBecause of the existence of yield gaps between yields measured underexperimental conditions at agricultural colleges and experiment stationsversus the yields obtained on farmer fields (Fig. 3), the yield benefit of Btbrinjal has been overestimated. This can be demonstrated as follows.Suppose Y Btis experimental Bt brinjal yield and Y nBtis the experimentalnon-Bt brinjal yield. The yield benefit of Bt brinjal is calculated in the MSTand LST as Y Bt– Y nBt. Because yields determined from experimentsoverestimate average farmer yields by the proportional yield gap, PYG E, bothY Btand Y nBtshould be multiplied by PYG Eto estimate the average farmeryields for the same experimental treatments. Thus, PYGE x Y Btand PYG ExY nBtestimate average farmer yields for the two experimental treatments.The yield benefit of Bt brinjal for the average farmer is consequently PYG EY Bt– PYG EY nBt, which can be rewritten as PYG E(Y Bt– Y nBt). Thus, the yieldbenefit for Bt brinjal was overestimated in the MST and LST by theproportion given by PYG E.The proportional yield gap for rice and maize can be estimatedfrom data published in Lobell et al. (2009). The majority of data on rice isfrom India. The data on maize is mostly from the US, Latin America andAfrica. The distribution of estimated proportional yield gaps is shown in thefigure below.The average proportional yield gap for these data is 54%.Considerable research efforts are expended to reduce the yieldgap (= bring the PYG up to 1.0) and bring average farmer yields up to thelevels obtainable on experiment stations. To do this, it is essential tounderstand the underlying causes of the yield gaps, which are many andvaried. The proportional yield gaps for US maize in Nebraska, the heart ofthe Corn Belt were 40% and 56%. These values are very close to the meanfor all countries, including many developing countries, so the high technologyused in the US does not eliminate yield gaps; likewise, Bt brinjal isunlikely to substantially reduce the brinjal yield gap. Probably the mostsignificant factors contributing to yield gaps are a class of factors related tolocal variation or field-specific factors (Lobell et al. 2009). These includefarmer variation in management and weather and soil conditions. Considerableeffort must be expended to reduce yield gaps (= raise proportionalyield gaps to 1.0). This implies for Bt brinjal that simply making thetechnology available to farmers will not result in the dramatic yieldincreases promised in EC-II. Instead, Mahyco and the Indian governmentmust invest considerable amounts in outreach efforts so any yield benefitscan be realized. Such an investment, of course, reduces the socialeconomic surplus that Bt brinjal might generate and thereby reducing itssocial value.
Page 1 and 2: Table of Contents 1Bt Brinjal Event
Page 3 and 4: Table of Contents iBt Brinjal:The s
Page 5 and 6: Summary and Conclusion 1Summary an
Page 7 and 8: Summary and Conclusion 3The EE-1 t
Page 9 and 10: Summary and Conclusion 5Event EE-1
Page 11 and 12: Summary and Conclusion 7Conclusion
Page 13 and 14: Context and Need 9standards for ER
Page 15 and 16: Context and Need 11and seek to incr
Page 17 and 18: Context and Need 13the reported yie
Page 19 and 20: Characterisation of Transgene 15Cha
Page 21 and 22: Characterisation of Transgene 17wor
Page 23 and 24: Characterisation of Transgene 19In
Page 25 and 26: Characterisation of Transgene 21Sci
Page 27 and 28: Environmental Risk Assessment 23Gen
Page 29: Environmental Risk Assessment 25thi
Page 32 and 33: 28 Bt Brinjal: The GEAC environmen
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Bt Brinjal The scope and adequacy of the GEAC environmental risk assessment

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