In Mexico, a collaboration programme of public and private research is developing virus resistant transgenic potatoes, aiming explicitly at small-scale farmers. This claim is backed by economic models, but interviews with the farmers concerned show that they are not likely to benefit from the new varieties.

Potatoes are considered one of the most important food crops worldwide, and in Mexico they represent the third most significant vegetable in terms of acreage and production volume, after tomato and pepper (see box). Second to late blight (Phytophtora infestans), virus diseases, especially potato leaf roll virus (PLRV) are widespread; potato virus Y (PVY) is frequent at higher altitudes.

In 1991, the Mexican public research centre Centro de Investigación y Estudios Avanzados - Unidad Irapuato (CINVESTAV) began a collaboration with the agro-biotechnology company Monsanto (USA) to develop virus resistant potatoes (see box and see also the article by Commandeur in Monitor No. 28). The project has generated transgenic potatoes resistant to PVY and potato virus X (PVX) by transferring viral coat protein genes, and potatoes resistant to PLRV by transferring a viral replicase gene to the plants. CINVESTAV scientists declared that the PVX and PVY resistant varieties would be available by 2002, but this deadline might not be met because the Instituto Nacional de Investigaciones Forestales Agricolas y Pecuarias (INIFAP), the national institute that is responsible for the field trails, has insufficient funding to undertake the trials regularly. The research concerns ten potato varieties: the white variety Alpha and nine coloured varieties: Rosita, Mozamba, Tollocan, Puebla, Michoacán, Mexiquense, Ireri, Norteña and Monserrat. Field trials are concentrating on Alpha, Rosita and Norteña.

If these varieties are released, they will be the first commercial transgenic varieties in Mexico generated in cooperation with local researchers. This project is unique because, from the beginning, small-scale farmers have been named as a target group. However, they were not consulted during the planning phase, nor have they been since. To evaluate the possible benefits of biotechnology for small-scale farmers, the Grupo de investigación Sociedad y Biotecnología (Biotechnology and Society Research Group) undertook a field study, interviewing these farmers in the mountainous areas of Mexico.

Potato production in Mexico Potato production in Mexico can be distinguished in two blocks, which differ along geographical, socioeconomic and varietal lines. The centre of the country. Here, the majority of potatoes are produced in rainfed fields, generally located in mountainous zones above 2000 meters altitude. Producers are mainly small-scale farmers who use predominately coloured potato varieties, with low yields (3 to 10 tonnes per hectare). Some states of the North and of the Bajio. These areas represent about 59 per cent of the acreage cultivated with potatoes. Here, cultivation is done mainly under irrigation and the yield is twice that of the central region, with maximum yields of up to 40 tonnes per hectare. Producers can be classified as agricultural entrepreneurs, cultivation is highly mechanized and only white varieties are grown. White varieties are bigger and have higher yields than coloured varieties, but coloured varieties are more resistant to pests and diseases and they can be grown at heights of up to 3500 meters altitude. Regardless of this, the main difference between white and coloured varieties is consumer preference based on the intended meals. Only a quarter of seed potatoes used in Mexico are certified; non-certified seed and native varieties are grown in most areas. Certified seeds come from 10 tissue culture laboratories and 17 propagation greenhouses where mostly white potato varieties are produced. The total potato acreage rose in the past to over 73,500 hectares in 1989, but since then it has decreased to 63,000 hectares in 1999. The loss of acreage has been compensated by an average yield increase from 14.5 tonnes per hectare in 1989 to 23 tonnes per hectare in 1999. The annual Mexican potato production is about 1.4 million tonnes, with a value of US$ 300 million. Some 17 per cent of the potato harvest is used as seed potatoes, 10 per cent is processed by the food industry and 73 per cent is used for direct consumption. Because of high production costs and high price variability as well as strong competition between regions and between large-scale and small-scale farmers, potato production is highly speculative. The North American Free Trade Agreement (NAFTA) grants Mexican potato producers a protection period from foreign potato imports. However, when protection ends in 2004, as many as half of the Mexican producers may no longer be viable due to cheap imports.

The CINVESTAV/Monsanto programme on transgenic potatoes Since 1991, Monsanto (USA) has trained scientists of the public research institute Centro de Investigación y Estudious Avanzados - Unidad Irapuato (CINVESTAV, Mexico) in its Life Sciences Center, both in genetic engineering techniques and field trials. This cooperation has been presented as a new model of technology transfer between private and public sector. In November 1995, Monsanto granted CINVESTAV a royalty-free and non-exclusive licence to use Monsanto technology. The aim of this agreement is to transfer virus resistance to potato virus Y and potato virus X (PVY, PVX) into ten different potato varieties. A year later, 1996, the scope was broadened to include the technology for potato leaf roll virus resistance (PLRV), because it was recognized that PLVR was a bigger problem for farmers than PVY and PVX. CINVESTAV is now authorized to develop, grow and sell the new transgenic varieties in Mexico, the Philippines, Africa, and Central and South America. Potato exports from Mexico to the USA are forbidden by the licence. In this way, Monsanto does not risk its share of the US market. In Mexico, the transgenic plants included in the agreement are protected as plant varieties, but not by patents since Mexican laws do not allow patents on plants. Even though, in the USA they are protected by patents. The ten varieties are the nine coloured varieties Rosita, Mozamba, Tollocan, Puebla, Michoacán, Mexiquense, Ireri, Norteña and Monserrat and the white variety Alpha. Alpha is the potato variety with the biggest acreage in Mexico, but it is not cultivated in the USA, Monsanto’s main markets. PLVR resistant Alpha varieties are excluded from the licence. The Instituto Nacional de Investigaciones Forestales Agricolas y Pecuarias (National Institute of Agriculture Research, INIFAP) is currently undertaking field trials in cooperation with CINVESTAV with the varieties Rosita, Norteña and Alpha, to assess them for characteristics such as virus resistance, vigour, yields, stability and size, and for biosafety measures. The results of these trials so far show a better performance for Rosita and Norteña than for the other varieties of this project. Independently of the project partnership with Monsanto, CINVESTAV has an ongoing project on transgenic insect resistant potatoes based on Bacillus thuringiensis (Bt).

Interviews with small-scale potato farmers

• 2300 to 2500 metres altitude: a variety of crops can be grown in combination with potato;
• 2500 to 2800 metres altitude: both potato and barley can be grown;
• up to 3500 metres altitude: no alternative production options except potatoes.

The objective of the study was to inquire into several aspects of potato agriculture:

• origin of seed;
• inputs, costs and yields;
• product and seed commercialization;
• agricultural practices;
• farmers’ general agronomic and socioeconomic situation, such as common crop diseases, the level of organization with other farmers, and their possible contacts with public or private institutions; and
• to asses the possible relevance of the new CINVESTAV varieties.

The situation of the farmers

• Use of bought and farm-saved seed potatoes
  If the small-scale farmers have enough money, they buy their seed potatoes from a laboratory in the region. More often, seeds are bought from an informal market. Such informal markets derive their products mainly from villages that have specialized in seed potato production because of a low pest and disease incidence in the area. For many farmers it is also a question of tradition and costs to use farm-saved seed potatoes and to obtain new ones only if a pest problem arises.
• Use of technological innovations and agro-chemical inputs
  The technological options are not uniform for potato farmers on different altitude levels. In the highest areas irrigation systems and machinery are hardly used, especially where the fields are so high that they can only be reached by climbing. Fortunately, pest and disease incidence is relatively low at higher altitudes.

  The villages in the study have had serious economic problems since 1989, because of falling potato prices and because of the strong competition of white varieties with higher yields, mainly Alpha, on the market. In the years before this crisis, a good cost-benefit ratio stimulated the input of agrochemicals. There was public sector support for an agricultural production system based on fertilizers, fungicides, insecticides and herbicides, and information on management problems was available. Recently, however, public technical assistance was abolished, and now the only technical assistance given is by the agro-chemical companies. If in the current situation agro-chemical inputs are reduced by the farmers, this is usually a financial rather than an environmental decision.

  The decision to use farm-saved seed potatoes or to buy new ones, also depends largely on the actual financial situation of the individual farmer. Potato yields in these villages vary between 3 and 20 tonnes per hectare. These variations are due to different production conditions, which depend on the presence of diseases and agriculture practices dealing with rain regime, plague control, fertilizing and plant density per hectare.

  Most of the small-scale farmers interviewed showed a great interest in any technological option that would increase their yields. Most farmers said that if CINVESTAV transgenic varieties were available, they would use them. For these farmers access to dominant technologies, both in terms of seeds and agro-chemical inputs, depends on their economic situation.

• Relevance of virus infections
  In general, virus infections are not a serious problem for small-scale farmers in these areas, but late blight (Phytophtora infestans) and worms (Golden nematode) are. When asked about the diseases of their potato crop, small-scale farmers reported symptoms caused by PLVR, but not by PVX or PVY. Even though farmers know the symptoms of PLVR, they do not know that this disease is caused by a virus.
• Lack of storage and distribution infrastructure
  Besides diseases, the major problem for the farmers is the lack of good storage conditions. In all but one of the villages visited, there were no special buildings for storing the seed potatoes; instead they are kept in the house yards or outdoors.
  Sale of the harvest is another problem. Since most farmers harvest at the same time and since they cannot store their products adequately, the surplus causes a decline in prices. Furthermore, a manipulative intermediate trade keeps the prices low, sometimes so low that it is not worth harvesting the potatoes.
  Falling prices lead to a reduction of the overall potato acreage. Where possible, farmers have tried to substitute potato with crops like broccoli, peas, onions, carrots and flowers. As farmers in the higher regions do not have this option, they are more interested in improving their potatoes, but they also look for complementary revenues in urban, non-agriculture activities such as construc- tion work or trading. Credits to finance potato production are scarce or even completely absent and most farmers who took on loans are now in debt.

Will small-scale farmers benefit from transgenic potatoes?

Virus resistant transgenic potatoes could contribute to agricultural sustainability if they could reduce the need for pesticides, but in order to achieve this, it is also necessary to increase farmers’ technical skills and their purchasing power to buy the seeds. At the moment, Mexican small-scale farmers only get technical assistance from local agro-chemical distributors who have other commercial interests. To introduce transgenic crops, CINVESTAV will have to establish an efficient link to small-scale farms. Unfortunately this requires additional funding which might not be available.

But still, socioeconomic, non-technical problems cannot be solved by technology and therefore the use of CINVESTAV’s transgenic potato varieties might prove to be unsuitable.

Different results from evaluating interviews and economic models

He comes to the following conclusion about the possible benefits for small-scale farmers: "if appropriate social support mechanisms can be implemented, the project could successfully demonstrate that modern proprietary biotechnology applications can help low- and middle-income countries meet their urgent development objectives."

At the moment, the research of the Biotechnology and Society Research Group shows less optimistic results about spreading the new technology to small farmers. One of the main weaknesses of small-scale farmers’ access to new transgenic varieties is precisely the lack of a public research service that could help them to propagate these seeds.

Qaim’s analysis is an economic one and therefore an important approach to study technological changes, but these kinds of processes are very heterogeneous and include economical, technical, political, social and cultural aspects.

Qaim’s technological framework uses assumptions based on political decisions with different assumptions leading to different scenarios. He states that the development of a technology is not a process that only goes in one direction, but that it has different stages and cross-connections, and based on this dynamic he assumes that an already existing institutional public programme can be the right mechanism to support the new technology of transgenic virus resistant potatoes. Currently, the influence of this programme to make seeds available to different kind of farmers is very limited, and its funding is scarce.

Qaim’s analysis considers different producers’ groups because technology adoption rates as well as farmers’ potential to increase productivity, can be very different in the various groups of large, middle and small-scale farmers. As Qaim recognized himself, the necessary data for this analysis is difficult to obtain in Mexico, but already these data include assumptions that limit the potential adaptation of a technology such as the virus resistant transgenic potato. This limit is not necessarily the only one possible, nor is it the desirable one.

In Qaim’s study the assumed model was that on a given acreage the conventional varieties would be completely substituted by transgenic potatoes, namely with one transgenic variety, Rosita. We consider this assumption neither desirable nor probable. In Qaim’s study it is assumed for technology adoption that Rosita would be the only red variety in Mexico because it is the most important one and more detailed data on varietal production shares are not available. He arrives at this simplification of reality from an economic point of view; however, the probability of such substitution should also be based on differences in the technology adoption capabilities between the different types of farmers. Also, it is not desirable to replace the agricultural diversity of currently more than ten different coloured varieties with only one transgenic variety. The restriction to Rosita in Qaim’s study might be a technical one, which the author himself also finds undesirable; but the desirable limit of technology adaptation should also include alternative biotechnological or conventional strategies that allow farmers to grow other products than potatoes.

A basic parameter for Qaim’s analysis was yield losses caused by different viruses. These data were obtained from expert estimations, but unfortunately there is no research available about the real incidence and effect of these viruses in the different potato regions in Mexico. There is also no experimental data that could show the impact of virus resistant potatoes on solving problems for small-scale farmers.

Since Qaim is assessing increase in yields, he does not consider possible environmental effects. In fact, he states that one cannot expect a different pest management regime as a result of using the new technology. Unfortunately, this contradicts one of the most important expectations of biotechnology in general and of the CINVESTAV project in particular: a reduced pesticide input against the insect vectors of the viruses where such pesticides are available and used now.

In the regions we studied, it stands out that several villages have become important as seed producers in an informal market where a lot of small-scale farmers buy their seed potatoes; there is even a certain supply from small-scale seed potato producers to middle-scale farmers. In contrast to this, Qaim bases his further conclusions on the estimation that most small-scale producers use farm-saved seeds. This biases his suggestion of a public institutional mechanism to distribute the new transgenic varieties. Under the present conditions we do not expect this distribution system to work out, because one of the main problems for small farmers is precisely the lack of a public research service that could help them to take decisions not only based on their current economic resources. It is claimed that governmental institutions should be responsible for bringing the new varieties to small-scale farmers, but these institutions are in a very shaky condition. In fact, some of the field trials that should have been undertaken by the INIFAP in North Mexico were not carried out because of the lack of funding.

Technological change is not unknown in those villages where local potato varieties are grown, but at this stage the question as to whether small-scale farmers will have access to transgenic virus resistant potatoes and whether they will benefit from it remains unanswered. If small-scale farmers in developing countries are to benefit from biotechnology, then it is important that the governmental policies not only attend their technological needs but also give them support in issues like storage and commercialization.
Yolanda Massieu, Rosa L. González, Michelle Chauvet, Yolanda Castañeda and Rosa E. Barajas

Biotechnology and Society Research Group, Sociology Department, Metropolitan Autonomous University-Azcapotzalco, Mexico City, Mexico.
E-mail ymt@hp9000a1.uam.mx

Sources
Qaim, M. (1998), "Transgenic virus resistant potatoes in Mexico." ISAAA Briefs, No. 7. ISAAA, Cornell, USA and ZEF, Germany.

Biotechnology and Society Group (1998), Impactos socioeconómicos de la aplicación de la biotecnología en la producción de papa en México. Metropolitan Autonomous University Azcapotzalco, Mexico City.