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Shands, H.L. 1990. Plant breeding: A reappraisal. p. 96-98. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.


Plant Breeding: A Reappraisal

Henry L. Shands

What is in store for the breeders in the next 30 years? When the earth spewed its 5 billionth person in June of 1987, it was on or slightly ahead of the schedule projected for an infinite population in 2028 as per the Doomsday Equation (von Foerster 1960). Now you and I don't really believe that the earth will have an infinite population in 2028. Malthus projected arithmetic increases in food supply and exponential increases in population. The Doomsday Equation uses an exponential equation to demonstrate that at this moment we are heading into serious trouble. There is no evidence that the extra 90 millions that we are currently adding net to the world's population annually will be deterred in any fashion (Umpleby 1987). In the U.S., the 123 millions of inhabitants in 1930 have now more than doubled in 58 years. Immigration into the U.S. accounts for 500-600 thousands per year.

What is the impact of the extra mouths to feed? That 90 millions each year is equal to 37% of the current U.S. population. How much food can the world produce? How much can the U.S. produce? For the 20 year period from 1968 to present, the U.S. average wheat yield increased at slightly over 1% per year while maize increased at about 2.3%. These figures do not represent breeder yield test figures but represent national statistics with such real life vagaries as crop area increases and decreases, weather, breaking new (or retiring) marginal lands (USDA 1988). Not too impressive if we see population increases of 2.2% to almost 4.5% in some of the less developed countries which are unable to feed themselves at this time or in the foreseeable future. Given that breeders have a major challenge ahead of them, consider the options open to increase yields to a satisfactory level. We cannot expect to have the U.S. feed the world. The question is when will the moral judgments insist that we must short ourselves to take care of our obligation to the world's hungry. That will come irrespective of the distribution problems alluded to as a current cause of surpluses and hunger. First, will come the shift from animal to plant products (vegetables and protein-loaded legumes and cereals). We already see the nutritionists guiding us in this direction. But, some 11% of the earth's area is considered arable and 22% of the area is considered useable for pasture. Certainly, that 22% must be retained in animal production for its contribution of food and animal product materials.

Every breeder has sought the miracle plant. Few have found it, figuratively or literally. Nor are they likely to do so. The Green Revolution plants in wheat and rice are still "on stream" while the increased production due to heterosis has already been utilized in maize and a number of minor crops. What is left? Double-cropping has been utilized to some advantage in certain areas but to the detriment of natural resources, land, and water. Imagine if our food supply hinged upon the double-crop agriculture of soybean and wheat through the rich, Midwestern farm belt. Water was inadequate in 1988 for the second crop, soybeans, and had it been even marginal, what would be the moisture reserve available for next year's crop? Could food resources ever be so fragile as to hinge on a year's double crop? Temperate climate breeders must look to potential multiple cropping systems where rainfall will sustain them. Development of photoperiod insensitive, fast cycle crops as reported by P.H. Williams in this Symposium may be necessary for future agriculture. Certain tropical climates permit three cycles of cropping such as for rice and alternates but will the land always permit that?

Breeders must be prepared to alter the crop improvement programs for irrigated areas to include drought stress resistance in the event that natural or legislative events force a discontinuance or reduction of irrigated systems. Water availability and quality is a serious global problem. In the U.S., the Ogallala reservoir subtending the Western Great Plains is being depleted by significant water useage for crop production (Brown 1988). Many believe those non-renewable glacial waters would be more valuable in the future for potable water if pollution renders other reservoir forms less desirable. Also, that water may be more valuable for crop production in the future when the price of the crops is truly set by supply and demand. The artificial prices of today's crops certainly do not make it rational to dissipate this valuable non-renewable resource.

The global warming trend which has received considerable attention as a result of the 1988 drought, makes the water issue more serious. It is thought that as the temperatures rise, crops will move northward. Unfortunately the breeders must make selective changes for not only temperature but also photoperiod adaptation, drought stress, and changing pest and rhizosphere situations. It will be difficult to develop the new strains ahead of time but it will be possible to create populations having the requisite components so that selection can be practiced forthrightly when the time comes.

Little, if anything, has been done to strategically alter the diversity and thus reduce the genetic vulnerability of major economic crops available on the farm (National Academy of Science 1972). This must start at the prebreeding level where diversity is infused into the breeding populations. Several forward-thinking breeders are developing new gene pools to this end. I believe it is a given, that commercial companies are not going to use material lacking the yield potential of existing stocks because they must compete for market share on a yield performance basis. Farmers demand it. Broadly based genetic populations must be developed and heterotic patterns discovered that produce at current population levels.

A second U.S. incident of corn blight (the new "C" race) has been averted by alert and cooperative international responsiveness but another cytoplasm has been removed from the present inventory of maize. After the discovery of the new race in the People's Republic of China (Wei et al. 1988), and its corroboration by a team of Federal, State and Industry scientists in the U.S., the industry responded by modifying and removing the C-cytoplasm maize hybrids from the market. The public research sector has a responsibility to get to work on a coordinated plan to further develop diverging genepools from which breeders develop inbreds and cultivars. New molecular tools are emerging where genetic diversity can be measured. This may be looked upon as defensive breeding; more appropriately it may be considered prudent breeding. Along the way, some scientists may find in near or distant relatives major quantitative trait loci, trackable through the new technologies, which will provide useful productivity or quality improvements.

The breeder of the future will be more dependent upon the world's germplasm for his crop. Organized breeding in institutions has been a luxury of the developed nations but a necessity for developing nations. Unfortunately, the developing nations have had numerous impediments to implementation of sound practices for a variety of reasons, be they political, economic, educational, or institutional. In 1983, the FAO became a forum for international activists to focus upon plant germplasm as an issue of contention. The concept that the world's gene banks should come under the domain of the FAO and that private companies must open their proprietary lines to the world have become issues which continue to cause concern for those in the politics of germplasm management. The activists are political and often fail to understand that germplasm in the form of hybrids and advanced varieties sold and provided to these countries is not constrained. Breeders may cross, select, and utilize those newly created forms in whatever way they want. These politicians at the same time threaten the basic philosophy of the free exchange of germplasm when the world, and they, need it most. Theirs will be a hollow argument as they stand in the midst of their landraces and low producing crops while millions starve around them. Breeders know the agony of the time lag to develop a new and acceptable inbred or cultivar-even for the incremental percentage that it adds. I challenge the international community to get off its negative stand of protectionism and to get on a soapbox for active exchange in the hope that the exchange, collaboration, and cooperation will help them before it is too late. Their intransigence will not help them secure food from even the most benevolent of nations when there are choices to be made. We must not only curb the population growth interactively but must work to increase the food supply as cooperatively as possible.

There are other major issues confronting breeders today as they develop refined advanced inbreds and cultivars. The Chakrabarty Decision of the U.S. Supreme Court and the subsequent ruling, ex-parte Hibberd, have caused significant concern by scientists, ethicists, and administrators. These decisions imply that the (utility) Patent Act of 1836 can now be applied to plants and suggest that anything touched by the hand of man can be patented. The potential of acquiring new revenue to support public programs from licensing and direct sales by these public institutions is a serious threat to the free exchange of germplasm between breeders and continued collaborative efforts. This institutional protectionism to utilization of critical, utilitarian developments in plant genetics and breeding transcends even the most overt attempts to restrict germplasm flow in the past. Breeders from all sectors must unite to enable the patented plants to be used for research and development, as put into practice in the Plant Patent Act of 1930 for the asexually propagated plants or in the Plant Variety Protection Act of 1970 for sexually propagated plants.

What is the bottom line? We know the consequences of increased population on consumption, waste, and desecration of the environment as we attempt self-sufficiency in food and shelter. Consumption of natural resources such as the petrochemical reserves will deplete them to the point where they are more valuable to certain priority uses. Before we exhaust the biodiversity of the globe, we must preserve the genetic resources which will enable an offsetting option for these chemicals. We must understand these crops and species that can supply these products and how they fit into agricultural systems. We must develop new crops capable of delivering the desired product in sufficient volume to make a difference. If the new crop utilizes too much valuable area in relation to its yield, the land area will likely be preempted by another crop. There must be a more deliberate effort to identify the resources needed and prioritize the available crop species. just because political pressure requires the present allocation of research resources does not make it correct or wise. Who is to take the lead in developing and implementing the new set of priorities? We need a mandate and support.

Perhaps we are our own worst enemies. We say we require funding but we don't need funding to prioritize. We do need a signal that there is a recognition that something is needed. It does not bode well for the future of agriculture that funding increases for agricultural research do not keep up with inflation while recent research and development funding is generally up significantly.

Our efforts are needed more now than ever before. Training programs have been reduced, and breeding programs have been cut. It is not popular to have an applied program. But soon the time will be too late to rapidly crank up breeding programs. Time will be against us. A plan to initiate a new breeding program will take only a short time to prepare but started from scratch may take 15-20 years to see the first results. And there is no guarantee that those first products will be anything better than what we have at present. We owe it to the future generations to get started now.

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Last update February 12, 1997 by aw