Plant Breeding at the University of Florida: Development of varieties with a high benefit to cost ratio

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1 1 Plant Breeding at the University of Florida: Development of varieties with a high benefit to cost ratio Abstract 2 Purpose 2 What is plant breeding and why is it important? 3 Importance of plant breeding in an age of excess farm production 3 Plant breeding and the world situation 4 Plant breeding at the University of Florida: A critical element in the history of Florida agriculture 5 Public-sector and private-sector plant breeding in Florida 6 Plant breeding and biotechnology 7 Plant breeding and the nature of crop varieties 7 Plant breeding and the teaching program 8 Plant breeding research 8 Plant breeding and IFAS Extension 9 Replacing retiring plant breeders in IFAS 10 Workgroup concerns about the future of plant breeding at the University of Florida 10 Steps needed to maintain a strong plant breeding program at the University of Florida 10 References 11

2 2 Abstract Much of the plant agriculture in Florida depends on varieties developed by plant breeders at the University of Florida. Because of Florida s unique soils and climate, because the market season for many Florida fruits and vegetables is not the same as in other areas, and because some important Florida crops are minor crops in other states, Florida growers cannot depend on other states for the varieties they need. Thus, plant breeding and variety development at the University of Florida are vital to the state s agricultural industries and to consumers here and throughout the country. The University of Florida is a world-wide leader in providing graduate training in plant breeding, and because many other land grant universities have reduced or eliminated their plant breeding programs, it is today more important than ever that we maintain a strong graduate program in plant breeding. Plant breeding research at the University of Florida has lead to new breeding methods, new varieties, and new production systems. Plant breeders are working with molecular biologists to see where new technologies can be applied in Florida. IFAS plant breeders work with extension personnel in helping growers choose varieties and solve problems that arise once the varieties are in the production fields. Plant breeding programs are long-term. Programs built up over decades cannot be stopped and restarted without great loss. The University of Florida Plant Breeders Workgroup believes that it is critically important to keep IFAS plant breeding programs strong. Of immediate concern is the need to replace retiring plant breeders, to maintain enough plant breeding programs on the Gainesville campus to give graduate students first-hand experience in plant breeding, and to maintain enough professors and students to support the teaching program. Among the breeding positions of greatest concern are replacement of the stone fruit breeder and the vegetable crops breeders at Gainesville, initiation of a food-legume breeding program in the Agronomy Department at Gainesville, filling the cucurbit breeding position, and initiation of a breeding program for tropical fruits and a breeding program for woody ornamentals. Purpose This paper was prepared by the IFAS Plant Breeders Working Group to discuss the importance, to growers and consumers, of plant breeding and variety development at the University of Florida. At a time when plant breeding has declined in the USDA and at many land-grant universities, we believe it is critically important that plant breeding remain a strong and vigorous component of agricultural research at the University of Florida. What is plant breeding and why is it important? Plant breeding is the art and science of developing, by the most rapid, efficient, and inexpensive methods available, crop varieties that have maximum utility to growers in a region and to the consumers for whom they grow. Almost every variety grown in Florida came from a plant

3 3 breeding program. Because it costs about the same per acre to plant good varieties or bad, but yields and quality are very different, plant breeding results in large benefit-to-cost ratios. New varieties may have any or all of the following improvements: higher yield, more resistance to diseases and insects, maturity dates that fall into more-profitable market windows, and higher quality characteristics. Such attributes increase consumer demand, reduce production costs, reduce pesticide use, maintain farm profitability, and allow development and expansion of new markets. Because new pests are continually evolving and new production areas are continually becoming more competitive, lack of breeding programs in Florida will not only mean a loss of progress, it will also mean declining yields and quality and the eventual disappearance of commercial agriculture from the state. Importance of plant breeding in an age of excess farm production The argument has been made that plant breeding is not now very important in the U.S. because U.S. farmers already produce too much food and fiber, commodity prices are unprofitable, and the government must legislate reduced acreage and subsidize farmers to keep them in business. We believe that low-cost, abundant food, available to all, is a major triumph of our civilization, not a problem. Never before in the history of the world have so many consumers spent so small a percent of their income for food. Even when food is abundant, plant breeding can contribute to achieving the following desirable outcomes: 1. Reduction in the amount of land and water needed for agriculture. Higher-yielding varieties can make more land available for wildlife conservation, for recreation, and for other uses. 2. Reductions in the amounts of pesticides, fertilizer, and energy used in farming. 3. Improvements in product quality, for example, better flavors in fruits and vegetables, vegetable oils with healthier fats, crops with higher levels of beneficial phytonutrients, and greater variety in fresh fruits, vegetables, and flowers. 4. Increased local production of food. Local production can save fuel, reduce highway traffic, and improve the freshness and quality of our food. Local food production keeps money in the state economy and can help preserve the quality of the environment in urbanizing areas. Varieties with better adaptation to Florida climates and soils will support local food production in the State. 5. Reduced need for migrant labor in farm production. Although migrant labor provides work for many people, its social costs are high, and it will probably continue to decrease in the long run. New varieties can make it possible to mechanize planting, pruning, and harvesting. 6. New crops. American diets, even for the wealthiest, could be much more interesting if our fruit, vegetable, and grain diets were more diverse. Hundreds of new crops await domestication

4 4 or accommodation to modern production and marketing methods. Plant breeding and the world situation Since 1970, world food production has increased faster than world population, but much hunger remains. About half of the increase in yield per acre of farmland over the past 50 years has been due to plant breeding (E.O. Wilson, 1992). During the 1970s, Norman Borlaug characterized the Green Revolution as having the potential to gain for the world 30 years during which population growth could be reduced to sustainable levels. Despite reductions in the rate of increase, world population is still rising rapidly. More food will be required as the world struggles to escape from poverty. Although wheat, field corn, and soybeans have not been major crops in Florida since the 1970s, this could change in the decades ahead. The following considerations point to a continuing need for plant breeding and other applied agricultural research. 1. World population continues to grow rapidly. Most of the increase is in the poorest countries (Grant, 1996). Much of the increase in world food production during the past 30 years has come from factors that are either destructive to the environment (such as rainforest conversion to farmland) or from inputs that cannot continue to increase at the same rate as in the past (such as irrigated acreage and fertilizer use). 2. Conversion of forests to new farmland, a major source of increased food production during the past 30 years, is having disastrous consequences. According to Edwin O. Wilson (1992), by reducing the area of the tropical rain forest, human activity has increased the rate of species extinction to between 1,000 and 10,000 times the natural background rate. Although new land continues to be brought into agriculture, opportunities for increasing farm acreage are near zero in some countries, and farmland is also being lost to urbanization. 3. Increased fertilizer use accounted for much of the increase in food production during the past 30 years, but gains from fertilizer are approaching limits in many countries. China and South Korea, for example, already apply three times as much fertilizer per acre as the U.S., and additional fertilizer gives little or no increase in yields (Grant, 1996). 4. Little water is available for irrigating additional acres. Much current irrigation is unsustainable, and uses nonrenewable (fossil) water, the pumping of which depletes aquifers and requires wells to be dug deeper and deeper. In some places, water previously used to irrigate crops is being redirected to urban use. This trend will continue as population grows. 5. It has been said that modern agriculture is a method of converting petroleum to corn, soybeans, wheat, and rice. With sharply lower petroleum output starting in a decade or two and with the likelihood that greenhouse warming will result in lower use of coal and oil shale, rising energy prices are likely to work against increased food production in the coming decades.

5 5 6. The collapse of native fish populations of many species due to over-harvesting indicates that this formerly free resource will contribute less to world food supplies in the future. Replacing self-sustaining wild fish populations with cultivated fish will increase the demand for corn and soybeans. 7. The migration of millions of people from impoverished countries into rich countries such as the USA, and the development of middle-class minorities in countries like China and India has greatly increased levels of food and energy consumption by large numbers of people. These demographic changes have enormous potential to increase consumption and demand for agricultural products in the future. 8. Efforts to decrease the consumption gap between the minority who live in rich countries and the majority who live in poor countries will, to the extent that they succeed, require either great decreases in American consumption or great increases in world food and energy production. The resources that would be needed to raise the world s poor to anywhere near the American living standard will be difficult or impossible to obtain. The University of Florida plant breeders do not contend that plant breeding can solve all the world s problems. We do contend that strong plant breeding programs will be important in dealing with the food, energy and environmental problems that must be faced during the next 50 years. Plant breeding at the University of Florida: A critical element in the history of Florida agriculture From the start of the Florida Agricultural Experiment Station, plant breeding was among the most important activities. Varieties and germplasm developed at the University of Florida have been the mainstay of Florida farmers, and the importance of Florida varieties has extended far beyond the borders of the state. Varieties bred and selected on the sandy soils of Florida, under the stress of hot, humid summers, are better adapted to the humid subtropics than varieties bred farther north. Thus, Florida varieties have been important to the agriculture of many tropical and subtropical countries. Varieties developed in Florida have contributed greatly to Florida agriculture. Since their release, pines that resist fusiform rust have contributed hundreds of millions of dollars to the value of Florida forest products. The high yields and superior quality of Florunner peanut allowed it to dominate peanut production in the southeastern USA for more than two decades. Recent development of high-oleic acid peanut varieties based on genetics discovered in the Florida peanut breeding program will greatly extend the shelf-life of peanut products. These peanuts will also allow peanut oil to rival olive oil in its ability to reduce the incidence of strokes and heart attacks. Strawberry varieties that yield more in December, January, and February have allowed Florida growers to take advantage of high prices at a time of the year when California has little

6 6 production. Incorporation of the shrunken-2 gene into commercial sweet corn varieties, which was accomplished at the Everglades Experiment Station during the 1960s and 1970s, transformed sweet corn production and consumption throughout the USA. The shrunken-2 gene allows fresh sweet corn to be shipped from Florida to distant markets with little loss of quality. Peach, plum, nectarine and blueberry varieties have been developed that are heat tolerant and have low chilling requirements. This allows them to be grown at low latitudes and makes possible the year-round availability of these fruit on the world market. The Florida varieties ripen in April and May in the northern hemisphere and in October and November in the southern hemisphere, months in which neither blueberries nor peaches could previously be harvested in either hemisphere. Florida s breeding programs for flowering, foliage, and turf crops have greatly improved and diversified the range of ornamental plants that can be produced commercially in Florida. Florida s forage breeding programs have helped preserve the state s beef and dairy industries. Many other breeding programs, including the development of a goodluck four-leaf clover, disease-resistant wheat and oats, tropical corn for silage production and disease-resistant tomatoes that can set fruit in hot weather, have made new agricultural enterprises possible. Public-sector and private-sector plant breeding in Florida Private seed companies breed some of the varieties that are grown in Florida. There are, however, several reasons why IFAS plant breeding is still necessary. These include: 1. Training future plant breeders. 2. Collecting, preserving, and studying germplasm for future use. 3. Developing, from wild or unadapted plant material, improved germplasm that can be finished into varieties by private breeders. 4. Developing inbred lines that can be used by private breeders to make hybrids. 5. Developing varieties of crops whose acreage is currently too small to interest private seed companies, especially in Florida. 6. Developing varieties for crops like citrus, in which the pay-off will be far in the future. 7. Breeding crops that are not currently grown in Florida. 8. Contributing to the IFAS extension program as it relates to crop varieties. 9. Providing unbiased information on the relative performance of varieties from competing companies.

7 7 10. Conducting the breeding-related research that is required in order to improve plant breeding methods. Plant breeding and biotechnology Strong plant breeding programs will be necessary if biotechnological innovations are to be marketed. Over the past 30 years IFAS has invested heavily in molecular biology research. As a result of worldwide research in molecular biology, the molecular basis of inheritance and the methods by which genes regulate cellular processes are understood in much greater detail than before. New information and new technologies will make it possible to change crop plants in new ways. For example, corn and soybean varieties could be made to produce pharmaceutical drugs, industrial plastics, or other useful products not normally associated with these crops. Through molecular techniques, food crops can be made more nutritious, plants can be made resistant to certain insects and diseases, and crops can be developed in which weeds can be controlled with herbicides to which the crops have been made resistant via genetic transformation. To take advantage of the new opportunities offered by biotechnology, vigorous, Florida-adapted varieties must be available into which the new molecular capabilities can be incorporated. Experience has shown clearly the folly of incorporating new biochemical capabilities into outdated varieties that are weak, poorly adapted, or poorly accepted by consumers. Thus, active plant breeding programs are needed to ensure that molecular biology research at the University of Florida results in practical applications. Some of the most promising agricultural research in Florida combines molecular techniques with traditional plant breeding. Budwood irradiation is being used to produce seedless forms of new citrus hybrids. Protoplast fusion is being used to produce hybrid citrus combinations that can be field-tested as rootstocks. Efforts are underway to make Florida papayas resistant to ringspot virus by transformation. Lack of resistance to this virus has previously frustrated efforts to breed high-quality, high-yielding papaya varieties for Florida. The Plant Breeders Workgroup is excited about the ways in which plant breeding and molecular biology can work together to create plants with new capabilities. Plant breeding and the nature of crop varieties Although varieties vary by crop, and include pure lines, F1 hybrids, clones, and open-pollinatedout-crossing populations, almost all successful varieties share the following characteristics: 1. High vigor (heterosis). Usually, the more vigorous the variety, the higher the yield potential and the more tolerant to stresses. 2. Resistance or tolerance to scores, sometimes hundreds, of potential diseases, insects, nematodes, mites, and other parasites that kill or weaken plants or reduce yield.

8 8 3. Specific adaptation to local conditions. Variety performance depends on soil type, temperature, humidity, photoperiod, light intensity, the probability of hail, freezes, drought, windstorms, rain during the harvest period, and other factors that vary from region to region. Although breeders try to select varieties with wide adaptation, variety x environment interactions usually dictate that the best varieties can only be developed by breeding and testing in the area where they are to be grown. 4. Acceptance by farmers, shippers, and consumers Successful varieties can only be developed by breeders who thoroughly understand the production, marketing and utilization of the crop. For many crops grown in Florida, time of ripening or specific quality characteristics are more important to grower profits than yield per acre. Breeders must know the possibilities inherent in the crop s germplasm, must stay in tune with the needs of the growers, and must recognize opportunities for solving grower problems with new varieties. Plant breeding and the teaching program Graduate students trained at the land-grant colleges are the main source of plant breeders in the United States. Plant breeding students require specialized courses in cytogenetics, population genetics, quantitative genetics, plant breeding theory and techniques, statistics, and experimental design. They also need the experience of working in a functioning plant breeding program. Having a practicing plant breeder as a research advisor gives students ideas and experience they could gain in no other way. Most students who graduate with majors in plant breeding from the University of Florida quickly find employment in plant breeding or closely-related fields. In addition to serving plant breeding students, courses in plant breeding are also needed by students of genetic engineering, plant medicine, international agriculture, and other disciplines. Plant breeding research As university professors, IFAS plant breeders breed varieties, teach graduate courses, and conduct research. Research areas to which plant breeders have made important contributions include the following: 1. Develop new crops and new varieties of old crops. 2. Plant breeding methods. Topics investigated by plant breeders include making and studying the characteristics of wide hybrids, storing pollen, obtaining haploid and polyploid plants, manipulating self incompatibility and apomixis, comparing the effectiveness of alternative breeding methods in various types of crops, developing methods of cloning plants, studying inbreeding depression and heterosis, studying the inheritance of various quantitative and

9 9 qualitative traits, mutation induction, exploitation of mobile elements to produce mutations, and the development and utilization of efficient marker-assisted selection schemes. 3. Plant systematics. Almost every crop has related species and genera with which it can be hybridized. By making wide crosses and studying the hybrids, plant breeders have helped delineate the relationships among the related taxa. Florida plant breeders have also contributed much to the sciences of plant ecology, plant physiology, and plant evolution. 4. Germplasm conservation. Due to human activities, plant and animal species are now becoming extinct at rates orders of magnitude higher than before the industrial revolution. Effective conservation efforts require much knowledge of plant diversity, population genetics, and techniques such as seed storage and regeneration. Plant breeders were among the first to concern themselves with germplasm conservation, and much more research is needed to extend conservation methods to minor crop species and to species not currently used in agriculture. 5. Investigations of plant mutants and anomalous segregants. While growing and observing hundreds of thousands of seedlings from segregating populations, plant breeders frequently find plants with new and unusual traits. These unusual plants may arise by mutation or by the segregation of rare alleles not previously detected. Many of these mutant alleles have either become important in agriculture or have provided keys to understanding important plant processes. 6.Other fields related to plant breeding. Plant breeding is an extremely inclusive science. At any moment, the breeder s main problem could be some disease, some insect, some post-harvest problem, some aspect of product chemistry, some crop reaction to a particular stress, etc. Much pioneering work in science has been done by plant breeders trying to solve problems that are impeding their breeding programs. Plant breeding and IFAS Extension IFAS plant breeders typically have split research-teaching appointments. Relatively few have official extension appointments. However, the informal contributions of plant breeders to IFAS extension programs are great. New well-adapted, pest-resistant varieties are essential for IFAS and for growers. Breeders work closely with growers in variety evaluation and testing. Breeders work closely with extension specialists in developing and communicating information on varieties and their culture to growers. Growers often make large demands on the time and resources of the breeders. Although breeders occasionally wish they had less contact with growers, such interaction is unavoidable and usually serves to benefit the breeders, the growers, and the extension specialists. In many cases highly synergistic interactions have developed between growers, extension personnel, and plant breeders.

10 10 Replacing retiring plant breeders in IFAS License fees paid by growers for use of IFAS varieties are increasingly important as a source of revenue to support plant breeding. However, strong plant breeding programs will continue to require strong support from IFAS. Well-managed, well-equipped research farms must be maintained. Technical support staff will continue to be essential if breeders are to conduct breeding programs and also carry out their other university duties. Retiring plant breeders need to be replaced with no loss of continuity between the departing breeder and the arriving breeder. Workgroup concerns about the future of plant breeding at the University of Florida The breeders are concerned that some University of Florida plant breeding programs that have been highly productive for many years are in danger of being discontinued or interrupted due to the retirement of plant breeders. Plant breeding programs develop momentum which can easily be lost if programs are interrupted. Germplasm is gradually improved over a long period of time; if it is lost or if its significance is not understood after a breeder retires, years of progress can be reduced to nothing. Although there are cases where crops have ceased to have potential for Florida farmers and the need to breed certain crops in Florida has diminished, new opportunities are continually opening for plant breeders. At the land grant Universities in many other states, plant breeding programs have lost support and have been discontinued. We think that loss of plant breeding programs at the University of Florida would be bad for growers, bad for consumers, bad for the environment, and a loss for science. The breeders are also concerned about graduate training in plant breeding at the University of Florida. Over the past 15 years, enrollment in plant breeding courses at Gainesville has declined sharply. This is due in part to a reduction in the number of plant breeding professors at the Gainesville campus. In the past, both the USDA and the University of Florida had numerous active plant breeding programs on campus, and breeders in these programs advised a large number of graduate students. As plant breeding activity on campus has declined, the number of plant breeding graduate students has declined to the point where it is difficult to maintain such key classes as population genetics, cytogenetics, and plant breeding. Steps needed to maintain a strong plant breeding program at the University of Florida 1. Hiring plant breeders for new positions and replacing retiring plant breeders. This is essential if strong plant breeding programs are to be maintained. Fewer and fewer U.S. students grew up on farms and have a knowledge of the importance of crop varieties and of practical farming systems. Partly because of this, relatively few students have been trained in plant breeding in recent years. If the plant breeders currently scheduled to retire on the DROP program are not replaced, particularly those on campus, some plant breeding courses will go untaught and the

11 11 number of students majoring in plant breeding may fall too low to justify the continuation of other classes. With declining student numbers, beneficial interactions among plant breeding graduate students will be lost. Germplasm that has been built up over decades will be lost. At the time of preparation of this paper, the plant breeders saw the following positions as having the highest hiring priorities: refilling the stone-fruit breeding position at Gainesville; refilling the vegetable breeding position at Gainesville; initiating a food legume (boiled peanut, cowpea, vegetable soybean) position at Gainesville; refilling the cucurbit breeding position; initiating a breeding program for tropical fruit and another for woody ornamentals. 2. Maintain plant breeding infrastructure. The patent and licensing system has provided critically-needed funds to maintain plant breeding programs at the University of Florida. It is imperative that most of the money generated by variety patents continues to be returned to the breeding programs that developed the varieties. IFAS also makes important contributions to the plant breeding programs in the form of technician salaries and support for the research farms. It is essential that this support continue. Research can be supported by extramural grants, but variety development is exclusively dependent on support from plant patent royalties and local industry support. 3. Support for new breeders and for the breeding of new crops. New breeders are under pressure to acquire grant support, teach, publish, and manage their breeding programs. IFAS policies must not encourage new plant breeders to short-change their breeding programs in order to accomplish their other University responsibilities. It is important that Department Chairs and Center Directors understand and support the breeding programs. Some crops that need to be bred for the benefit of Florida growers and consumers have little inherent possibility of generating significant revenues from licensing fees. These should be supported by IFAS where possible. New breeders will require support for their programs until they are able to generate research funds from variety licensing. References Grant, Lindsey Juggernaut, growth on a finite planet. Seven Locks Press, Washington, D.C. Wilson, Edward O The Diversity of Life. W. W. Norton & Company, N.Y.