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

GM Crops: The First Ten Years
using conventional tillage fell 25.6% (to 5.8 million ha), the area planted using reduced tillage
increased by 7.0% (to 11.9 million ha) and the area planted using no till increased 39.0% (to 11.1
million ha, equal to about 38.5% of the total 2005 crop).
The most rapid rate of adoption of the GM HT technology has been by growers using NT systems
(GM HT cultivars accounted for about 99% of total NT soybeans in 2005). This compares with
conventional tillage systems for soybeans where GM HT cultivars accounted for 80% of total
conventional tillage soybean plantings (Table 52).
Table 52. US soybean tillage practices and the adoption of GM HT cultivars 1996-2005
(million ha)
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
Total
area
26.0
28.3
29.1
29.8
30.1
30.0
29.5
29.7
30.3
28.9
No till
8.0
8.7
9.4
9.7
10.0
10.2
10.3
11.0
11.7
11.1
Reduced
till
11.1
12.0
12.8
12.9
12.9
12.6
12.3
12.4
12.5
11.9
Conventional
till
6.8
7.6
6.9
7.3
7.2
7.2
6.9
6.3
6.1
5.8
Total
GM
area
0.5
3.2
11.8
16.4
18.2
22.2
24.3
25.7
27.2
26.9
Total
Non
GM
area
25.5
25.1
17.4
13.4
11.9
7.8
5.3
4.0
3.1
2.0
No till-
GM
area
0.24
1.91
4.81
6.12
7.48
8.38
9.31
10.46
11.39
11.02
Reduced
till GM
area
0.17
1.20
4.45
7.07
8.23
9.39
10.49
11.18
11.26
11.33
Source: Adapted from Conservation Tillage and Plant Biotechnology (CTIC) 2002
NT = no-till + ridge till, RT = reduced tillage + mulch till, CT = conventional tillage, GM = GM HT varieties
Conventional
tillage GM
area
0.07
0.08
1.97
3.2
3.83
4.39
4.46
4.07
4.56
4.54
The importance of GM HT soybeans in the adoption of a NT system has also been confirmed by an
American Soybean Association (ASA) study (2001) of conservation tillage. This study found that
the availability of GM HT soybeans has facilitated and encouraged farmers to implement reduced
tillage practices; a majority of growers surveyed indicated that GM HT soybean technology had
been the factor of greatest influence in their adoption of reduced tillage practices.
a) Fuel consumption
Based on the soybean crop area planted by tillage system, type of seed planted (GM and non-GM)
and applying the fuel usage consumption rates presented in section 4.2.1 89 , the total consumption
of tractor fuel has increased by about 19.9 million litres (from 752.7 to 772.6 million litres 1996 to
2005: Table 53). As the area of soybeans increased by 2.9 million ha over the same period, the
average fuel usage fell 7.7% (from 29.0 litres/ha to 26.8 litres/ha: Table 53). A comparison of GM
versus non GM production systems shows that in 2005, the average tillage fuel consumption on the
89 Our estimates are based on the following average fuel consumption rates: NT 14.12 litre/ha, RT 28.83 litres/ha (the average of fuel
consumption for chisel ploughing and disking) and conventional tillage 46.65 litres/ha
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