Agroecologia y sustentabilidad

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Agroecología y Desarrollo Rural Sostenible en América
Miguel Altieri University of California, Berkeley
Seminario Interno CIAT - Febrero 8, 2006

Derechos reservados: Universidad de California, 2006

Peasants were bypassed by agricultural modernization
• Technologies were imposed and did not emerge from a participatory process • Technologies were not appropriate to the needs andcircumstances of peasants • Technologies were not scale neutral (favored larger farmers or those with access to capital, credit, best lands, etc)

Global Pesticide Consumption
• 67% global increase in pesticide use from 1983-1998 • US $34.1 billion dollars in 1998 • 138% increase in pesticide use in Latin America same period • Globally 4.1 billion pounds applied annually

Soybean inArgentina (tons-red, has-blue)
35.000 30.000 25.000 20.000 15.000 10.000 5.000 0 71/72 74/75 77/78 80/81 83/84 86/87 89/90 92/93 95/96 98/99 01/02

Deforestation rates in Argentina due to advance of transgenic soybean ( 1998-2002)
• Chaco 117,974 hectares • Salta 160,000 “ • Santiago del Estero 223,000 “

Table Nº 2. Reduction of number of agricultural farms in Argentina by Regions. YearTotal Pampas NEA* NOA** Cuyo Patagonia 1988 421.221 196.254 85.249 72.183 46.222 21.313 2002 317.816 136.345 68.332 63.848 32.541 16.750 Difference % - 24,5 - 30,5 - 19,8 - 11,5 - 29,6 - 21,4 Source: On the basis of data from Censo Nacional Agropecuario 2002, INDEC. (*NEA: Northeast Argentina, **NOA: Northwest Argentina). www.indec.gov.ar, date: 11/11/04

pink bollworm

Is Bt cottoneffective?
verticillium wilt
armyworm

boll weevil

armyworms
cabbage looper cabbage looper

Bt cotton

Bud-Bollworm

bollworm

whitefly

whitefly
cotton aphid

time

Lygus bug
thrip

Lygus bug

• Bollgard cotton controls …. tobacco budworm and pink bollworm while supplemental control is needed to control bollworm, soybean looper, armyworms and other non-caterpillar pests. “ •WHY?

Concentration of Bt toxin in cotton

mg Cry1Ac toxin /g dry weight

160

120

Greenplate 1999

9th node fruit
80

terminal foliage

40

0 53 74 95 116

days after planting

Magic bullet: one gene one pest
• Targeting one species (pink bollworm) may results in different rate of resistance development and increased levels of some pests due to reductions in naturalenemy efficacy, increases that may require additional insecticide use against highly tolerant pests ( bollworm, fall armyworm, soybean looper, Lygus bugs)

Orders of tolerance of cotton pests to Bt toxin
Fruit pests: • Lygus> fall armyworm>bollworm>budworm>pink bollworm Foliage pests: • whitefly>soybean looper>beet armyworm>cabbage lopper

Lygus
100

fecundity 75 -150

percent survivingon Bt cotton

FAW
80

800+

60

BAW

800+

40

CL

800+

20

PBW
0 1.0 1.2 1.4

CBW TBW
1.6

500+ 500+ 150 - 250

normalized developmental time (days)
on conventional (Ο) and Bt (♦) cotton

Table Nº 3. Estimation of nutrients (N, P) exportation and the reposition cost for soybean harvest 2002/2003 (34.000.000 metric tons)

Nutrient Extraction 1.020.000 in metrictons Equivalent in 2.217.400 Mineral Fertilizers in metric tons Cost stimation 576.524.000 reposition (US$)
Source: PENGUE 2003.

Nitrogen

Phosphorous
227.800 1.109.386 332.816.000

Total
1.247.800 3.326.786 909.340.000

Soybean expansion at the expense of food security
• In one decade soybean area increased in 126% at the expense of areas of dairy, maize , wheat and fruits • in2003/2004 13,7 million has of soybean were planted displacing 2,9 million has of maize and 2,15 million has of sunflowers

Emergence wordlwide
• 23 million hectares under organic agriculture globally (10,6 million in Australia includes grazing land) • Italy: 56,000 organic farmers occupying 1.2 million hectares, and 8,000 in Germany using 2% arable land. • North America : 1,5 million has farmed...
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