GM Crops: The First Ten Years - International Service for the ...

GM Crops: The First Ten Years
b) China
Since the adoption of GM IR cotton in China there have been substantial reductions in the use of
insecticides. In terms of the average volume of insecticide ai applied to cotton, the application to
a typical hectare of GM IR cotton is about 1.35 kg/ha compared to 6.02 kg/ha for conventionally
grown cotton (a 77% decrease: see Appendix 3) 77 . In terms of an average field EIQ load/ha the GM
IR cotton insecticide load is 61/ha compared to 292/ha for conventional cotton.
Based on these differences the amount of insecticide ai used and its environmental load impact
has been 51% lower in 2005 (Table 46) than the levels that would have occurred if only non GM
cotton had been planted. Cumulatively since 1997, the volume of insecticide use has decreased
by 30% (76 million kg ai) and the field EIQ load has fallen by 28% (3 billion field EIQ/ha units).
Table 46. National level changes in insecticide ai use and field EIQ values for GM IR
cotton in China 1997-2005
Year ai decrease (kg) eiq savings (units)
1997
158,780
7,843,630
1998
1,218,870
60,211,395
1999
3,054,180
150,874,530
2000
5,678,720
280,525,120
2001
10,152,580
501,530,930
2002
9,807,000
484,459,500
2003
13,076,000
645,946,000
2004
17,279,000
853,571,500
2005
15,411,000
761,293,500
% decrease in ai
1
4
14
25
35
39
42
50
50
% saving eiq
1
5
14
25
36
40
43
51
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c) Australia
Using a combination of data from industry sources and CSIRO 78 , the following changes in insecticide
use on Australian cotton have occurred:
• There has been a significant reduction in both the volume of insecticides used and the
environmental impact associated with this spraying (Table 47). The average field EIQ/ha
value of the single Bt gene Ingard technology was less than half the average field EIQ/ha
for conventional cotton. In turn, this saving has been further increased with the availability
and adoption of the two Bt gene technology in Bollgard II cotton from 2003/04;
• The total amount of insecticide ai used and its environmental impact (Table 48) has been
respectively 65% (2.18 million kg) and 67% lower in 2005, than the levels that would have
occurred if only conventional cotton had been planted;
• Cumulatively, since 1996 the volume of insecticide use is 23% lower (9.26 million kg) than
the amount that would have been used if GM IR technology had not been adopted and the
field EIQ load has fallen by 22%.
77 Sources: based on a combination of industry views and Prey et al (2001)
78 The former making a direct comparison of insecticide use of Bollgard II versus conventional cotton and the latter a survey-based
assessment of actual insecticide usage in the years 2002-03 and 2003-04
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