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The lack of weed control technology was highlighted by this
system. If the period between two subsequent crops was too long,
weeds established and used available soil water.
Producers started to discuss no-tillage amongst themselves and
thought this new idea was foolish and that such a big revolution in
the system was impossible to put into practice. Understandably,
this new concept of no-tillage was difficult for producers to compre
hend – especially for those who had been following conventional
practices for many years.
The newly introduced technology and ideas were foreign and the
conversion was huge. Most producers started to realise the potential
of no-tillage when crop yields increased and the impact of the new
methods on the environment was not significant when compared to
the traditional, conventional methods.
By the end of the 1980s, the Argentine Association of Direct Sow
ing Producers (Aapresid) organisation emerged. This organisation
is non-governmental, non-profit and patronised by producers and
agronomists from across Argentina. The mission of Aapresid is to
promote sustainable production systems of food, fibre and energy
through innovation, science and network knowledge management.
Currently, Aapresid is funded by approximately 2 000 producers
from 30 regions across Argentina.
Input (chemical) companies saw the opportunity to increase their
business and initiated help in adapting technology associated with
no-tillage. This led to the release of glyphosate herbicides and
opened the door to promote no-tillage much faster, as effective
weed control was now a possibility.
The glyphosate herbicide was, however, very expensive at that
stage, but due to the overall lower inputs of a no-tillage system it
was possible for producers to follow this route. As time went on,
glyphosate herbicides became cheaper, which further improved the
economic viability of the system.
As both wheat and soybean were part of the cropping systems
during the early stages of no-tillage adoption, producers realised
the possibility of including other crops such as maize. As time went
on, producers became more familiar with the new concepts and
methods of no-tillage and viewed technology as a possible gateway
to adapt the system according to their needs.
In 1996, Roundup Ready soybeans were introduced in Argentina.
Soon after, a large number of producers entered the no-tillage sys
tem in a very short period of time (
Graph 1
). Glyphosate could now
be used for weed control during the soybean growing season and
fallow periods. Weeds that were difficult to control could now easily
be dealt with.
From there onwards, the surface under no-tillage doubled annually.
Soybean was the principle crop, while the area under wheat and
maize was very low. However, monoculture soybean production
was harmful for the ecology of the Pampas and led to, among oth
ers, depleted soils, primarily due to the low levels of crop residue
production, soil organic carbon reduction and poor nutrient cycling.
After some time, producers introduced maize and wheat more
frequently in their production systems to increase crop diversity.
Currently, the introduction of cover crop species such as triticale,
oats and radish are being investigated (by researchers and produc
ers) to further increase crop diversity, livestock integration, more
effective weed control between summer crops and improved soil
water utilisation.
In 1992, only 1,8 million ha were under no-tillage in Argentina. This
figure currently stands at 34 million ha, representing 91% of the total
cropped area (see Graph 1).
CROP
AREA HARVESTED
(HA)
TOTAL PRODUC-
TION (TONS)
AVERAGE YIELD (T/HA)
WATER USE
EFFICIENCY*
OF NO-TILL
CONVENTIONAL
NO-TILL
Soybean
19 504 648
58 799 258
2,43
3,38
7
Maize
5 346 593
39 792 854
6,58
8,42
20
Wheat
5 629 213
18 557 532
2,93
3,24
11
Table 1: Area harvested and total production for soybean, maize and wheat for the 2015/2016 production year.
* Water use efficiency in kg/mm/ha
Source: Food and Agriculture Organization (
http://www.fao.org/faostat/en/#data/QC
)
Stephano Haarhoff and Dr Hendrik Smith at one of many no-till planter companies in Argentina.