The economics of BT cotton production in India--a meta analysis.
Chakraborty, Kalyan
Appendix
Table A
Summary of Peer Reviewed Published Studies on the Economic Impact of
Bt Cotton on Farmem in India
Author/Study/Date Location Sample/Data
Herring (2009) India Essay
Subramanian and Maharastra, Farm statistical
Qaim (2009) Karnataka, survey, 341
Andhra Pradesh, farmers: 133-Bt
Tamil Nadu plots; 301-non-Bt
plots 2002-03
Maertens (2009) Andhra Pradesh 3 Villages, 246
households, panel
data 2001-2008
Herring (2008) Andhra Pradesh One village, 2006
Rao, Rao, Andhra Pradesh, 180 Farmers
Naraiah, Guntur surveyed
Malathi, and practicing IPM
Reddy (2007) with and without
Bt and non-
IPM , 2004-05
Roy, Herring, Gujarat, 4- 45 Farmers were
and Geisler districts: interviewed; 35-
(2007) Junagadh, Bt and 10-non-Bt
Bhavnagar, farmers,
Sabarkantha, Summer, 2004
Vadodara
Qaim, Subramanian, Maharastra, Farm statistical
Naik, and Karnataka, survey, 341
Zilberman (2006) Andhra Pradesh, farmers: 133-Bt
Tamil Nadu plots; 301-non-
Bt plots 2002-03
Morse, Bennett, Maharastra, Farm statistical
Ismael (2007) Jalgaon survey: 137-
Bt plots; 95-
non-Bt plots.
2002-03
Crost, Shankar, Maharastra, Farm level survey
Bennett, and Jalgaon data from 6
Morse (2007) villages: 718-plots;
338-farmers;
84-Bt only;
122-non-Bt only;
134-both, 2002-03
Kambhampati, Maharastra Survey by Mahyco:
Morse, Bennett, Khandesh,
and Ismael (2006) Marathawada,
Vidarbha
7,751-plots 20021,
580-plots 2003
Bennett, Maharastra; 7,751-plots 2002
Kambhampati, Gujarat, 1,580-plots 2003
Morse, and Madhya Pradesh,
Ismael (2006) Karnataka
Kambhampati, Morse, Gujarat Interview: 22 Up-
Bennett, and stream and down-
Ismael (2005) stream companies:
Sabarkantha,
Ahmedabad,
Gandhinagar,
Mahesana, 2004
Morse, Bennett, Gujarat Farm statistical
and Ismael survey: 622.
(2005a,b) farmers; 306-plots
official Bt;
169-plots
unofficial Bt;
151- non-Bt
Bennett, Ismael, Maharastra Survey by Mahyco:
Kambhampati, Khandesh,
and Morse (2004) Marathawada,
Vidarbha 7,751-
plots 20021,580
-plots 2003
Pemsl, Waibel, Karnataka Survey data:
and Orphal (2004) Dharwad and
Belgaum. 100
Bt and Non-Bt
farms; Irrigated
-44, Non-irr-66;
2002-03
Barwale, Gadwal, Andhra Pradesh, Survey by Mahyco:
Zehr, and Zehr Gujarat, 1069-farms,
-2004 Karnataka, 2002-03
Madhya Pradesh,
Maharastra,
Tamil Nadu
Qaim and Zilberman Maharastra, 157-Trial Plots
(2003) Madhya Pradesh from 25 districts,
Tamil Nadu 2001
Author/Study/Date Method Used
Herring (2009) Narrative
Subramanian and Social Accounting
Qaim (2009) Matrix (SAM)
Multiplier model
Maertens (2009) Probit model of
Quasi-Panel
Herring (2008) Narrative
Rao, Rao, Two-way contingency
Naraiah, table testing
Malathi, and correlation between
Reddy (2007) Bt adoption and
practice of IPM.
Regression analysis.
Roy, Herring, Survey data analysis
and Geisler
(2007)
Qaim, Subramanian, Regression analysis:
Naik, and Estimating translog
Zilberman (2006) production function
Morse, Bennett, One-way ANOVA
Ismael (2007) table, comparison
between Bt adopters
and non-adopters
Crost, Shankar, Estimated Cobb-
Bennett, and Douglas production
Morse (2007) function using panel
data fixed effect
model
Kambhampati, Estimated frontier
Morse, Bennett, production function
and Ismael (2006) using panel data
Bennett, Estimated Cobb-
Kambhampati, Douglas production
Morse, and function using
Ismael (2006) 2-year panel data
Kambhampati, Morse, Survey data analysis
Bennett, and
Ismael (2005)
Morse, Bennett, Farm survey
and Ismael analysis
(2005a,b) and Econometric
Stepwise
Regression
Bennett, Ismael, Farm survey
Kambhampati, analysis
and Morse (2004)
Pemsl, Waibel, Stochastic partial
and Orphal (2004) budgeting;
Multiple linear
regression
Barwale, Gadwal, Farm survey
Zehr, and Zehr Analysis
(2004)
Qaim and Zilberman Regression analysis
(2003) of pesticide use
function and
production function
with Pesticide
Author/Study/Date Results
Herring (2009) Concludes Bt cotton has proved a scale-neutral
partial solution to a pressing agronomic problem,
bollworm destruction. Evidences found in the
literature that the technology is pro-poor, which
implies larger harvest creates more work for
labourers.
Subramanian and Found Bt cotton is associated a substantial
Qaim (2009) overall generation of rural employment
especially among female workers. The returns to
saved management time in alternative activities
are higher for large farmers hence the large
farmers benefit more from Bt adoption in an
economy-wide framework.
Maertens (2009) The magnitude of the coefficient measuring the
change in probability to adopt Bt cotton after
having heard of one additional institutional
source is about 4-40 times the magnitude of the
coefficient of learning from one additional
fellow farmer.
Herring (2008) The study found that "innocent error in fording
Bt cotton failure, revolving around germplasm,
spurious seeds, and trait differentiations."
Economics and environmental integrity
coincided--environmental toxin declined with
Bt technology
Rao, Rao, The study found plant protection expenditure is
Naraiah, lowest when IPM is practiced with non-Bt
Malathi, and varieties. Practice of IPM would reduce the cost
Reddy (2007) of plant protection and increase the net return.
No significant reduction of plant protection cost
was observed when Bt varieties were adopted
without IPM.
Roy, Herring, Found similar to conventional cotton farmers, Bt
and Geisler cotton farmers are more likely to use saved seeds
(2007) (34%) and both large and small farmers used
'loose' seeds, officially approved and illegal
transgenic seeds. Laborers are benefited in
terms of amount of wages earned due to higher
yields from Bt cotton.
Qaim, Subramanian, Found Bt plots had less spray (2.6 times), higher
Naik, and yields (34%), and higher profits (Rs. 2,161) more
Zilberman (2006) than conventional cotton plots. Andhra Pradesh
suffered losses because of high pesticide use and
severe draught, and spurious Bt seeds.
Morse, Bennett, On average Bt plots are higher yielding (27-42%)
Ismael (2007) and have higher revenue (34-53%) than non-Bt
plots. Overall, the gross margins of Bt plots are
significantly higher (59-66%) than non-Bt.
Between adopters and non-adopters, about the
half of the increase in yield for Bt adopters is
due to 'farmer effect' and the rest is due to
Bt-trait.'
Crost, Shankar, Found efficient farmers adopt Bt cotton at a
Bennett, and higher rate than less efficient farmers. When
Morse (2007) self selectivity bias is controlled, Bt cotton
farmers are found to have 31% yield advantage
over non-Bt farmers.
Kambhampati, Average yield for Bt plot increased by 45% and
Morse, Bennett, 63% for 2002-03 compared to non-Bt plot.
and Ismael (2006) Increased performance of Bt could be any of the
following factors: Bt gene, the base cotton
variety used performed well in local conditions
and the farmers might be more efficient.
Bennett, For 2002, the production function estimates
Kambhampati, indicate Bt technology has a 33% positive effect
Morse, and on yield per acre after allowing for influence of
Ismael (2006) insecticide sprays, soil type, and irrigation. For
both Bt and non-Bt varieties yield rise under
irrigation however, the impact of irrigation is
highly significant under Bt variety.
Kambhampati, Morse, Companies sold less pesticide as a result of
Bennett, and farmers used Bt cotton. Due higher quality Bt
Ismael (2005) cotton need to be separated from other cotton for
higher price. Farmers are less reliant on credit
for purchasing pesticide and higher price for Bt
cotton would benefit the farmers most.
Morse, Bennett, Average yield benefits 37% for MECH-12, 20%
and Ismael for MECH-162, 14% for unofficial Fl, -5% for
(2005a,b) unofficial F2, Gross margin also follow the same
order - +132%, +73%, +37%, +20%.
Bennett, Ismael, For Bt cotton adopters the cost of bollworm spray
Kambhampati, is lower by 72% in 2002 and 83% in 2003.
and Morse (2004) Average yield for Bt cotton increased by 45%
(2002) and 63% (2003) over non-Bt. The average
gross margin for Bt was higher by 74% (2002)
and 49%(2003) than non-Bt.
Pemsl, Waibel, The study found under non-irrigated conditions
and Orphal (2004) there would be no reason for farmers to adopt Bt
cotton. Under irrigated conditions stochastic
dominance shows pesticide alone is the superior
strategy. The regression analysis found pest
pressure and cotton output price largely
determine the yield.
Barwale, Gadwal, On average Bt cotton yields were 30% higher
Zehr, and Zehr than non-Bt hybrids and Bt had a cleaner quality
-2004 and color. Bt farms had 1.93 less spray for
bollworm when combined had an additional Rs.
18,000/ha compared to non-Bt.
Qaim and Zilberman Average yields for Bt hybrids exceeded yields for
(2003) non-Bt and popular checks by 80% and 87%
respectively. Bt hybrids were spread three times
less against bollworm than non-Bt and popular
checks.
Appendix
Table B
Summary of Non-peer Reviewed Studies/Reports and Working Papers
ISAAA (2009) India State level Farm data
published data, analysis
2002-2008
Krishna, Maharastra, Personal interview: Cobb-Douglas
Zilberman, Karnataka, 362-farmers-2004 production
and Qaim (2009) Andhra 344-farmers-2006 function (plot);
Pradesh, Tobit damage
Tamil Nadu function (farm)
Subramanian and Maharastra, Farm statistical SAM-Village
Qaim (2009) Karnataka, survey, 341 level
Andhra farmers: 133-Bt microdata
Pradesh, plots; 301-non simulation
Tamil Nadu -Bt plots 2002/3
Kanzara, 2004
Rao and Dev Andhra Stratified sample Regression
(2008) Pradesh: survey, 437-Bt analysis:
Warangal, farmers; 186- Estimated
Nalgonda, Non-Bt; 2004/5 production
Guntur. and 2006/7 function.
Kurnool Farm survey
analysis
Rao and Dev Andhra Stratified sample Regression
(2007) Pradesh: survey, 437-Bt analysis:
Warangal, farmers; 186- Estimated
Nalgonda, Non-Bt; 2004/5 production
Guntur, function. Farm
Kurnool survey analysis
All major IMRB-Survey of Farm data
cotton 5,950 farmers, analysis
growing 60% Bt adopters,
states in 2006/7
India
Gandhi and Gujarat, Farm statistical Regression
Namboodiri Maharastra, survey, 694 analysis and
(2006) Andhra farms 2004 farm survey
Pradesh, analysis
Tamil Nadu
Morse, Bennett, Maharastra 7,751-plots in Kruskal-Wallis
and Kambhampati (Khandesh, 2002; 1,580-plots non-parametric
(2005) Marathawada, in 2003; 22- tests; Frontier
Vidarbha); companies (seed/ production
Gujarat, AP, input/textile)- function
Karnataka 2004
ISAAA (2009) Between 2002 and 2008 Bt cotton acreage
increased by 42%, the consumption of pesticide
decreased by 22%, and the insecticide use
reduced by 20%. Since the introduction of Bt
technology in 2002, the yield increased from 308
kg/ha to 580 kg/ha in 2008.
Krishna, Bt technology and varietal richness increased the
Zilberman, mean yield and decreased yield variability.
and Qaim (2009) Farmers' economic welfare can be greatly
enhanced by introducing diversity among GM
varieties.
Subramanian and Bt cultivation increases the aggregate return to
Qaim (2009) labor by 42% and the return to hired female
labourer is 55%. For poor landless labourers,
their household income increases by 134% under
Bt cultivation than under non-Bt.
Rao and Dev Compared to 2004/5, yield for Bt cotton in 2006/7
(2008) increased by 42% and the use of chemical
insecticide decreased by 56%. There was a net
gain to the cotton farmers for Rs. 7,122 crores in
2006/7. Benefits in rain fed farming were lower
and were not statistically significant.
Rao and Dev Study finds that the overall Bt cotton decreased
(2007) pesticide cost by 18%, increased total cost by
17%, and increased income by 83%. Regression
estimates find 36% advantage of Bt over non-Bt
and Bt has a positive effect on farm employment.
However, due to bad weather in 2004/5 in
Andhra Pradesh total net income was negative
for both Bt and Non-Bt.IMRB (2006)
For India as a whole, Bt increases yield by 50%,
reduces pesticide costs by 32%, and increases
profit by 162%. All states gain from Bt cotton, the
biggest relative profit increase is in Maharastra
(375%), Andhra Pradesh (217%), Gujarat (198%)
and Madhya Pradesh (156%).
Gandhi and Regression analysis found Bt provides 31% yield
Namboodiri gains but costs 7% higher for a higher profit of
(2006) 74% on average. However, the percentage
increase of yield, costs, and profits vary from
state to state. Survey analysis also found almost
all farmers in Andhra Pradesh and Tamil Nadu
want to plant Bt in the future.
Morse, Bennett, The average difference in yield between Bt and
and Kambhampati non-Bt was 45% in 2002 and 63% in 2003. Two
(2005) most important benefits of growing Bt cotton are
increasing household income and reducing
insecticide use. Higher profit is not due to
reduced costs, but due to higher yield from Bt
variety.
Table 1
Commercialization of Bt-Cotton in India
Crop Year Area Bt-Cotton Per cent of Total Number of
(Hectare) Cotton Area Farmers
2002/03 44,500 0.58 54,000
2003/04 100,000 1.31 --
2004/05 500,000 5.57 300,000
2005/06 1,300,000 14.38 1,000,000
2006/07 3,800,000 41.27 2,300,000
2007/08 6,200,000 68.88 3,800,000
2008/09 7,600,000 82.00 5,000,000
Source: ISAAA--2008
Table 2
Adoption of Bt Cotton in India, by Major States, 2002 to 2008
(000 Hectares)
State 2002 2003 2004 2005 2006 2007 2008
Maharastra 25 30 200 607 1,840 2,800 3,130
Andhra Pradesh 8 10 75 280 830 1,000 1,320
Gujarat 10 36 122 150 470 980 1,360
Madhya Pradesh 2 13 80 146 310 500 620
Northern Zone * -- -- -- 60 215 682 840
Karnataka 3 4 18 30 85 145 240
Tamil Nadu 2 7 5 27 45 70 90
Others 5 5 5
Total 50 100 500 1,300 3,800 6,200 7,605
* Punjab, Haryana, Rajasthan Source: ISAAA, 2008
Table 3
Top-10 Cotton Producers in the World, 2008-09
Country Haruested Area Yield (lbs/ Production (480lbs/
(000 acres) acre) bales) (000 bales)
China 14,703 1,169 35,800
India 23,161 466 22,500
USA 7,569 813 12,815
Pakistan 7,166 603 9,000
Uzbekistan 3,509 629 4,600
Brazil 2,051 1,287 5,500
Turkey 853 1,182 2,100
Australia 405 1,719 1,450
Turkmenistan 1,483 437 1,350
Greece 618 893 1,150
Source: NCC of America (Cropdata)
Table 4
Approval of Bt Events and Hybrids for Commercial Cultivation
Year Events No of Hybrid
Varieties
2002/3 MMBL's Bollgard I 3
2003/4 MMBL's Bollgard I 3
2004/5 MMBL's Bollgard I 4
2005/6 MMBL's Bollgard I 20
2006/7 MMBL's Bollgard I & II; JK Seed's Event 1,
Nath Seed's GFM Event 62
2007/8 MMBL's Bollgard I & II; JK Seed's Event 1,
Nath Seed's GFM Event 162
2008/9 MMBL's Bollgard I & II; JK Seed's Event 1,
Nath Seed's GFM Event; and CICR Event 281
Source: ISAAA, 2008
Table 5
Votes on the Determinants of Bt Cotton Adoption--Samples with
Statistical Models (16 studies)
Numbers Numbers
Significant
Variables Included Pos. Neg. Insignificant
Farm Characteristics
Location 1 1 0 0
Farm size 8 3 1 4
Irrigation 7 5 0 2
Soil quality 4 2 0 2
Farm Inputs
Pesticide 9 5 3 1
Insecticide 8 2 5 1
Fertilizer/Manure 7 3 1 3
IPM Technology 1 0 1 0
Human labor 7 4 0 3
Bt-Seed 7 4 1 2
Bunny & other seed 3 1 0 2
Others 3 2 1 0
Farmer /Household
Age 6 0 2 4
Experience 3 0 0 3
Education 7 2 1 4
Family size 3 0 1 2
Net revenue 4 4 0 0
Family income 2 2 0 0
Significant
Percent Percent
Variables Included Included
Farm Characteristics 31 68
Location 6 100
Farm size 50 50
Irrigation 44 71
Soil quality 25 50
Farm Inputs 35 71
Pesticide 56 89
Insecticide 50 87
Fertilizer/Manure 44 57
IPM Technology 6 0
Human labor 44 57
Bt-Seed 44 71
Bunny & other seed 19 33
Others 19 100
Farmer /Household 26 62
Age 37 33
Experience 19 0
Education 44 43
Family size 19 33
Net revenue 25 100
Family income 12 100