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Re: [SANET-MG] Bt cotton not as useful for small farmers



Hello Hector,
I would like to add to your report one from Cornell showing that in China secondary pests resulted in the loss of profitability in GM cotton within a few years of cultivation. Interestingly, the refuges were heavily sprayed with broad spectrum insecticides and this may have slowed the damage from secondary pests in USA. I have for many years questioned the use of broad spectrum pesticides in the "refuges" because that just killed any mutants resistant to the Bt. Why call it a refuge when it is actually a pest killing zone? However in China it is clear that BT cotton evolved into an expensive loser.
sincerely, joe cummins

http://www.cals.cornell.edu/cals/public/comm/news/archive/seven-year-g

Seven-year glitch: Cornell warns that Chinese GM cotton
farmers are losing money due to 'secondary' pests
July 25, 2006
By Susan Lang
Although Chinese cotton growers were among the first farmers worldwide to plant genetically modified (GM) cotton to resist bollworms, the substantial profits they have
reaped for several years by saving on pesticides have now been eroded.
The reason, as reported by Cornell University researchers at the American Agricultural Economics Association (AAEA) Annual Meeting in Long Beach, Calif., July 25, is that other pests are now attacking the GM cotton.
Shenghui Wang, an economist with the World
Bank, interviews a Chinese cotton farmer about
using Bt cotton and how much spraying was
required after several years of use. Wang, who
received her Ph.D. from Cornell in 2006,
participated with Cornell researchers in the first
study to look at the long-term impact of Bt cotton
in China.
The GM crop is known as Bt cotton, shorthand for the Bacillus thuringiensis gene inserted into the seeds to produce toxins. But these toxins are lethal only to leaf-eating bollworms. After seven years, populations of other insects -- such as mirids -- have increased so much that farmers are now having to spray their crops up to 20 times a growing season to control them, according to the study of 481 Chinese farmers in five major cotton-producing provinces. "These results should send a very strong signal to researchers and governments that they need to come up with remedial actions for the Bt-cotton farmers. Otherwise, these farmers will stop using Bt cotton, and that would be very unfortunate," said Per Pinstrup-Andersen, the H.E. Babcock Professor of Food, Nutrition and Public Policy at Cornell, and the 2001 Food Prize laureate. Bt cotton, he said, can help reduce poverty and undernourishment problems in developing countries
if properly used.
The study -- the first to look at the longer-term economic impact of Bt cotton -- found that by year three, farmers in the survey who had planted Bt cotton cut pesticide use by more than 70 percent and had earnings 36 percent higher than farmers planting conventional cotton. By 2004, however, they had to spray just as much as conventional farmers, which resulted in a net average income of 8 percent less than conventional cotton farmers because Bt seed is triple the cost of
conventional seed.
In addition to Pinstrup-Andersen, the study was conducted by Shenghui Wang, Cornell Ph.D. '06 and now an economist at the World Bank, and Cornell professor David R. Just. They stress that secondary pest problems could become a major
threat in countries where Bt cotton has been widely planted.
"Because of its touted efficiency, four major cotton-growing countries were quick to adopt Bt cotton: the U.S., China, India and Argentina," said Wang. Bt cotton accounts for 35 percent of cotton production worldwide. In China, more than 5 million farmers have planted Bt cotton; it is also widely planted in Mexico and South Africa.When U.S. farmers plant Bt crops, they, unlike farmers in China, are required by contracts with seed producers to plant a refuge, a field of non-Bt crops, to maintain a bollworm population nearby to help prevent the pest from developing resistance to the Bt cotton. The pesticides used in these refuge fields help control secondary pest populations on the nearby Bt cotton fields. Researchers do not yet know if a secondary pest problem will emerge in the United States and
other countries, Pinstrup-Andersen said.
"The problem in China is not due to the bollworm developing resistance to Bt cotton -- as some researchers have feared -- but is due to secondary pests that are not targeted by the Bt cotton and which previously have been controlled by the broad-spectrum pesticides used to control bollworms," added Pinstrup-Andersen, who also is serving as president of
AAEA for 2007.
Wang and her co-authors conclude, "Research is urgently needed to develop and test solutions." These include introducing natural predators to kill the secondary pests, developing Bt cotton that resists the secondary pests or enforcing the planting of refuge areas where broad-spectrum pesticides are used. This study was jointly conducted by the Center for Chinese Agricultural Policy, Chinese Academy of Science and Cornell.


Hector Valenzuela wrote:
Hi all-

The 2 yr study below indicated that BT cotton was not as useful for small scale farmers in South Africa. Some pesticide applications were still required.
The authors surmise that the technology may be more beneficial/adaptable for large-scale farmers. If so this would contribute towards the concentration of land, and larger plantations, a continuation of the trends observed with the high-input tecnologies promoted by the green revolution.

A,

Hector Valenzuela
Univ. of Hawaii at Manoa


/////////////////////////


Abstract

This paper explores insecticide use in fields cropped with conventional or Bt cotton varieties in a smallholder farming area (Makhathini Flats, KwaZulu Natal, South Africa). The study was carried out during the 2002–2003 and 2003–2004 growing seasons as part of a broader survey based on daily monitoring of a sample of smallholdings. The adoption of Bt cotton led to a decrease in pyrethroid use, but the level of insect resistance of this cultivar was not sufficient to completely drop this pesticide from the spraying programme. On the other hand, organophosphates were still being applied in substantial amounts, thus raising questions as to the impact of Bt cotton adoption on farmers’ health. The overall economic results obtained with Bt cotton were slightly positive despite the low
cotton yields obtained in the Flats during our survey. Bt cotton adoption did lead to labour savings, but the extent of this gain was not as high as expected. In conclusion, cropping Bt cotton in Makhathini Flats did not generate sufficient income to expect a tangible and sustainable socioeconomic improvement due to the way the crop is currently managed. Adoption of an innovation like Bt cotton seems to pay only in an agro-system with a sufficient level of intensification.

Citation:

Jean-Luc Hofs, Michel Fok, and Maurice Vaissayre.
Impact of Bt cotton adoption on pesticide use by smallholders.
A 2-year survey in Makhatini Flats (South Africa)
Crop Protection 25 (2006) 984–988

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