Saturday, January 06, 2007

Hybrids or Improved Populations for Poor Farmers : A Breeder's Debate

K K Vinod, Javed Sidiqui, Konnie Frederick, Jorge Venegas, Raquel Guedes, Scott Matthew Dworak, Mauricio Erazo-Barradas and Brian Patrick Bresnahan

During one of our threaded discussions, my Professor  of University of Nebraska-Lincoln, Dr Stephen Baenziger was asking us of the choice of recommending improved populations or hybrids for the poor farmers of a country. Following is a note prepared on the discussion that went on the board.
There were thirteen messages of discussion. There were arguments favoring hybrids and improved populations but, general opinion largely favored the latter. 

The first respondent, Javed Sidiqui, had the preference to choose and release the improved seed to a the poor and small farmer's community considering the facts like, hybrid seeds are expensive and poor farmers may be unable to buy it in every season for cultivation due to its high price and also they can not use the seed from one year to another while having access to improved seed offer them the opportunity to save their own seed for next cultivating season. Furthermore, hybrid seed requires more dose of fertilizers, much greater amount of water and technology.

Improved seeds have to be tested at different phases to be adoptable in the region where it is cultivated in view of tolerance of drought, disease resistance, and other abiotic stress conditions. Javed concludes saying, as plant breeders we are responsible for producing improved seed based on specific farming conditions and needs of the poor farmers, because they may be dwelling in marginal farm environments (e.g., poor soils, and little rainfall) and my not be having adequate money to buy, fertilizers and pesticides; for they depend mostly on plants that survive and produce under adverse conditions year after year. 

Konnie Frederick however, suggested in favor of hybrids arguing, if the poor small farmer gets a hybrid he can select the best plants prior to pollination to improve his crop for next year.  He can then save seed and trade seed with another farmer who has a different hybrid and cross those.  By being able to barter with other farmers in his surrounding area, he can improve his crop yield.

Jorge Venegas while respecting Konnie’s ideas cautions that, reality in our poor countries is different. Commonly, our poor farmers do not have access to this technology; of course, that is simply to us, but they do not have education and funds to give to this hybrid its requirements. Therefore, if we want to implement a hybrid production program in a poor country, we have to be sure of the complete adoption of these hybrids in the poor farmers. The support of government and nongovernmental organisms is a main point in this technology implementation. Jorge adds that we must think that these hybrids require optimal conditions to produce very much. However, commonly the poor farms have strong conditions or marginal farm environments as Javed said previously. His experiences in Honduras and Ecuador, both poor Latin countries, where poor farms are localized in the most difficult terrains, on very inclined slopes and poor soil make him to suggest in favor of improved populations.

Scott Matthew Dworak, however, fully backed Javed’s ideas, adding that many of small-scale farmers who farm mainly for their own food supplies are unfortunately ignored by giant seed companies, who typically release hybrid seed, because the poor farmers aren’t viewed as attractive customers to these giant firms.  Market-based solutions are not an effective means in this aspect; poor farmers, like Javed said, lack the resources to pay for hybrid seed and manage it via cultural practices.  These farmers, located in rural areas, continue using farm-saved (improved) seed simply because they are not integrated into the market economy.   Distribution and/or allocation of resources may need to be addressed.

Konnie however, argues that if several of the smaller farmers’ pool their seed order they may be able to get a better deal on hybrid seeds than if they bought it by themselves.

I chose to complement Javed and Scott for their comments and presented my views focusing on a country where there are predominantly poor farmers, where we can expect these farmers to have low yielding crop varieties, mostly may be landraces. Agro-management also may be poor. However, these varieties may be highly locally adapted, having better quality, better resistance to biotic and abiotic stresses and good genetic variation. They may have less genetic purity due to outcrossing and unscientific propagation practices. In a situation like this, introduction of hybrids is not advisable due to following reasons.

a. High cost of hybrid seeds, which farmers may not be able to afford

b. Poor agro-management practices may not be suitable to exploit full potential of the hybrids

c. Farmers have the practice of advancing the seeds of his crop to next crop, which will result in a mixture of segregating materials if he uses a hybrid.

d. May not be suitable to his taste of quality

It is more prudent to go for population improvement under such situations. He emphasizes on subsistence farming rather than a market based approach, as a need to adopt under such situations. Different landraces can be improved separately by mass selection or recurrent selection procedures, and the traits can be combined if required using hybridization and selection. Once the yield levels are pulled up combining with good quality, pedigree breeding can be looked into. This will definitely improve the farmers returns also and his financial positions. He need to be taught about good agro-management practices and made aware of them. 

When farmers become self sufficient and are looking for a market, the hybrids can be introduce to him, which he would be able to buy, and grow as per the needs of the market, while adopting good management.

Raquel Guedes discussed that if he was to working in a country with poor farmers he would choose hybrids. Poor farmers who have lack of money to buy expensive hybrid seeds, they can buy double cross or three-way cross hybrids that are less expensive than single cross hybrids. These seeds are also more adapted to adverse soil and climate conditions and more resistant to diseases. He believes development is reached with high technology. If open-pollinated varieties (OPVs) would be the solution, developed countries would not be using 100 % of hybrid seeds.

Approximately 58% of the maize area in developing countries is planted to improved maize: 44% to hybrids, 14% to improved OPVs, and 42% to unimproved OPVs. In contrast, nearly 100% of maize area in the developed countries is planted to hybrids. Improved OPVs are easier to develop than hybrids; their seed production is more simple and relatively inexpensive (CIMMYT, 1994; Pandey and Gardner, 1992). The farmers who grow them can save their own seed for planting the following season, reducing their dependence on external sources. However, OPVs do not produce as much as hybrids. 

Crossing the progeny of a single cross with an unrelated inbred results in a three-way cross hybrid [(A x B) x C]. Crossing the progeny of two unrelated single crosses results in a double-cross hybrid [(A x B) x (C x D)]. Single-cross hybrids result from crossing two unrelated inbreeds (A x B). Single-cross hybrids generally have higher grain yield and less variability in appearance and maturity than do the three-way and double crosses because they are genetically uniform and they also cost more (Extension Service of Mississippi State University, 1914). 

Furthermore, governments would also need to make sure that there is some assurance that farmers are going to receive a fair price for their product at harvest time, and this price must reflect the international price for that commodity.

Mauricio   Erazo-Barradas prefered to release an improved population rather than a hybrid. While agreeing partially with the answer/argument provided by Raquel, Mauricio would stick to the idea of releasing an improved population. This improved population would be a "better" open pollinated population (better OPV) that would be developed using two different approaches/methodologies proposed by Pandey and Gardner (1992) and CIMMYT (1994), briefly described as;

a. Regardless of the recurrent selection scheme employed, 8-10 superior families should be identified based on their performance in multi-location tests. Using their remnant seed, the selected families should be intermated by making plant-to-plant diallel crosses among them to form an OPV. Diallel crossing among 10 or fewer genotypes is easily accomplished, permits more complete recombination, and reduces inbreeding (Hallauer and Miranda, 1988). In the crossing block, if a family looks different from other families during any stage of its growth and development, it can be discarded before or after pollination. Plants of other families fertilized with pollen from the undesirable family must also be discarded. 

b. Superior OPVs can also be developed by recombining elite inbred lines not derived from a population improvement program. In this case, it is desirable to select 8-10 lines with high general combining ability and intermate them as described before. High-yielding OPVs have also been developed by crossing among four or five single- or two or three double-cross hybrids. It is recommended that the parents of the hybrids- that is, the inbred lines- be selected and used instead of the hybrids themselves to form an OPV. This is because general combining ability is more important in the performance of OPVs than specific combining ability (which plays a greater role in the performance of hybrids).

Konnie  continued to emphasize on the importance of hybrids, says that the Green Revolution has done a lot to help poor and the underdeveloped countries become sustainable in its own food production.  The large seed companies have also jumped into help out, however the rapid progression of biotechnology has done little to aid in putting a curb on world hunger.  Biotechnology may be helping the developing countries, but it has done little to help the poor as they can not afford to purchase seeds to advance their crops thru technology.  Hybrids are less expensive and more beneficial to the poorer farmers as soil conditions and rainfall all play a big role in increased production; whereas an improved population variety may not do as well in the adverse conditions that may be presented in specific area.  

The farmers in question are not producing corn to sell on the open market, but for their own food consumption.  They have very few resources that are available to them and the big seed companies overlook the very small producers who may only buy one bag of seed corn a growing season.  These farmers are more likely to save their own seed from year to year to cut expenses, so the hybrid would be the best choice to begin with.

Scott Matthew Dworak went ahead with his idea by taking alfalfa (an autotetraploid) as a good option, if the seed can be made inexpensively enough for the farmers.  Segregation is restricted to a great degree in alfalfa varieties.  Not all genotypes can occur in early generations of seed increase, and several generations are required for all segregates to appear.  For example, in a 6-parent variety more than 17,000 distinct genotypes are formed at a locus in the third generation, while the first generation is relatively uniform.

Plant-to-plant variation is limited in the early generations of seed increase.  The greatest change comes in the Syn 2 generation, and variety stabilizes in the Syn 4 (Busbice and Gurgis, 1976).  Early generations may differ dramatically from later generations.  The Syn 1 and Syn 2 represent the breeder and foundation seed generations, respectively, and often are tested under experimental designations.  It is the Syn 3 and Syn 4, which represent the third and fourth generations of seed increase, respectively, that are sold to farmers as planting (certified) seed.  Based on alfalfa’s autotetraploid genetics, the Syn 1 and Syn 2 generations are more uniform than the commercial variety and higher yielding than the commercial variety (Busbice and Gurgis, 1976).  This means that all traits influenced by heterosis or genotypic structure such as yield, plant height, and persistence are confounded by the generation of seed increase.  For these traits, commercial varieties must be compared using commercial seed samples, not experimental ones.

If Syn 1 or Syn 2 seed could be sold to the farmers at an inexpensive price, farmers would get relatively uniform yields, which would be ideal.  Furthermore, alfalfa is a leguminous species, so the crop would freely add nitrogen to the soil, reducing expensive fertilizer costs in the future for the poor farmers.

Brian Patrick Bresnahan, is focused on the problem how he as a plant breeder would train his efforts on what is feasible, desirable among those who are going to be his customers, the recipients of the breeding program. His experience in Iraq forces him to think more of populations rather than hybrids. He calls that the question one should ask himself in addressing the problems of poor farmers is that, "what are my objectives? What do the farmers need and want in this poor, rural country?". Sure, they could use hybrids, especially if hybrids were available which fit the specific growing conditions and agronomic conditions of their area.  He recalls of a dozen corn hybrids he had seen in some of the salty, drought prone, sandy, high pH soils of Southwest Nebraska, western Kansas, and the Panhandle of Texas that would have been interesting to try in the fields west of Fallujah, Iraq where he worked for some time.  Although the staple grain was wheat in that area, some corn was planted and the potential for more corn did exist.

However, in reality, with regard to corn seed, none of the small farmers he worked with in Iraq had the money for hybrid seed.  They were subsistence farmers, just trying to feed themselves another year.  Thus, the corn they planted was open pollinated, saved seed.  At times they were provided one of two hybrids (one from Iraq the other from Jordan) if the government provided them that for the year, but they mostly relied on their own, saved seed, or saved seed they purchased elsewhere in their villages.  So, to fit that group, as a breeder, he would work on improved populations because they couldn't afford hybrid seed and could at least stand a chance of improving yields over time.

Additionally, in many of the countries he visited did not have the infrastructure to support a government funded breeding and seed production program for distribution to their country's farmers. That leaves the seed industry, which has been pointed out by others, is not likely to invest in such small, unstable, likely unprofitable markets. So, again, efforts would have to focus on improved populations as a cheaper alternative because it would have to be assumed that funding for the research and the distribution of seed in a poor country would be limited.

He went ahead of suggesting that, if funding were available, say through a USAID funded program implemented by a land grant university, he could start a corn breeding program in the poor country, long term though, developing hybrids to fit the farms which are owned and operated by the few elite/rich farmers in the country, something that seems to be consistent. With hybrids, the agronomic and production challenges the farmers face are much easier/quicker to overcome than with improved populations. Over time, if the government stabilizes, the older hybrids might be made available to the poor farmers through a government program. 

If the market/acreage among this group was initially large enough and potentially profitable enough, there could be a possibility for commercial funding, or at least continued U.S. federal funding as long as the political interests deem it a priority.  Which in and of itself might be another reason to focus efforts, and limited resources, on improving populations because political priorities are sure to change and multi-national corporations are fickle when it comes to profitability.    


Busbice, T. H. and Ramzy Y. Gurgis. 1976. Evaluating parents and predicting performance of synthetic alfalfa varieties. USDA, ARS-S-130. June 1976.
CIMMYT. 1994. CIMMYT 1993/94 World Maize Facts and Trends. Maize seed industries, revisited: Emerging Roles of the Public and Private sectors. Mexico, D.F. 
Extension Service of Mississippi State University, cooperating with U.S. Department of Agriculture. Published in furtherance of Acts of Congress, May 8 and June 30, 1914.
Hallauer, A.R., and J. B. Miranda Fo. 1988. Quantitative genetics in maize breeding. 2nd ed. Iowa State University Press, Ames, IA.
Pandey, S., and C. O. Gardner. 1992. Recurrent selection for population, variety, and hybrid improvement in tropical maize. Advances in Agronomy 48: 1-87

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