OVERVIEW OF COMMERCIALVEGETABLEBREEOING RESEARCH(VARI_-FYDEVELOPMEN!].)
L.R. BAKER, EXECUTIVEDIRECTOR,VEGETABLE R & DASGROW SEED COMPANY,KALAMAZOO,HI 49001
PREFACE
This presentation is not meant as a documentary of the seed trade. It
represents personal and professionalviews of the author who was at
Michigan State University as a public breeder in vegetable breeding
research for 13 years followed by his current position with Asgrow Seed
Company. The main thrust of this paper is to provide a discussion of
private vegetable seed company research for proprietaryvarieties.
INTRODUCTION
The advent of hybrid varieties to replace open-pollinated varieties
makes possible the protection of proprietarydevelopmentsand product.
Hybridization of vegetable speciesbegan in the 1920's with sweet corn,
followed by onions in the 1940's. Since that time, most species Of
vegetables have been changed into hybrid varieties for the marketplace.
Most recently, hand-pollinatedvarietieshave been developed, but costs
for hand-pollinated seed production are relatively expensive compared
to open-field production. However, the advantages of hybrid
performance related to uniformityand vigor have outweighedthe cost of
seed.
Most recently, plant variety protection (PVP) in the'U.S., and other
forms of protection throughout the developed countries of the world,
have afforded product security for species where hybridizationis not
possible(1). The latter would include the major vegetable speciesof
peas and beans. Such product protection has presented a business
incentive to corporations to invest in the seed industry (EXHIBITI).
Most seed companies were "family-owned" operations based upon
individual breeding successes in localized markets. For example, the
Clark family owned the Asgrow Companywhich excelled in the development
20 (over)
and production of high quality bean and pea varieties for processing.
Joseph Harris owned the Harris Seed Company in Rochester, New York, and
commanded a lead position throughout the northeastern U.S.in several
vegetable species con_only produced in that region. The introduction
of corporate business to the seed business permitted in major infusions
of capital. This supported a dramatic increase in private R & D
followed by strong competition in the marketplace between these major
seed companies.
The major worldwide vegetable species and estimated seed values are
presented below based on market surveys by Asgrow (EXHIBIT 2). The
estimated worldwide market value of these vegetable species is $I010MM.
A general estimate of R & D activities in the seed business approaches
10% of sales for R & D. Such an estimate would generate $100MM for
varietal development and other aspects of private seed research. Seed
companies have upgraded facilitiesand research staff over the last 10-
15 years. Plant breeders with Ph.D. degrees in genetics and plant
breeding with vegetable/horticulture backgrounds are commonplace
throughout the vegetable seed industry. The capability and
responsibility to develop proprietary varieties is commonplace
contrasted to previous public varieties. Prior to the 1970's, plant
breeders were more involved in seedstock work than varietal
development.
The transition for variety development from the public to the private
sector is well along. The cost for R & D to develop new varieties is
shifting from the public supported research programs to the customers
of the major seed companies. The majority of current varietiessold are
proprietary products developed by private R & D. These varieties are
more dependable in performance and available on a more reliable basis.
A significant consequence of the private increase in R & D for variety
development has been a reduction in public breeding work to develop
varieties. There is no question that the continued need for
fundamental breeding research is critical to support developmentof new
technology and expansion of the knowledge base which support varietal
development.
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Competition between proprietary varieties results in owner-companies
doing the best possible research to develop their own products and to
compete on genetic and physiologicalquality of seed in the marketplace
rather than price. Public varieties tend to be highly sensitive to
price; and therefore,cost saving measures are often taken in order to
compete on the basis of price. This often leads to a "running-out_ of
originally superiorvarieties. Reasonable profit margins are necessary
to pay-back the R & D costs to the owner and fund future research on
developing even better varieties to stay competitive in the
marketplace. There is considerable genetic variation within the
various vegetable specieswhich can be exploited in the developmentof
proprietary superior varieties. The consequences of this dynamic
situation will mean relativelyshort-livedvarietiesreplaced by either
the owner of _he variety or a competitor company. This intense
competition w_l mean constantly improved and more sophisticated
varieties for the vegetable industry.
GERMPLASM
The term germplasm means different things to different people.
Generally, it has been defined as germ that from which the next
springs, and plasm formative material...the bearer of the
characteristic nature of the species and individual. Germplasm
connotates the science of heredity and genetics, but implies the
unknown mysteries of the spark of life. No wonder that developed
nations have collected and saved it over the last 50 years. The USA
has some 250M plant germplasm accessions stored in the National Seed
Storage Laboratory (NSSL) in Fort Collins, CO. The epidemic in field
corn of southern corn leaf blight in 1970 struck a devastatingblow to
corn production i_ the USA. The upshot of this was a NationalAcademy
of Science (NAS) study in 1972 which identified the genetic
vulnerabilityof our major food species. The result was to establisha
National Plant Germplasm System to collect, maintain, describe and
enhance germplasm.A Plant Introduction(PI) Service has been operated.° .
by the United States Department of Agriculture (USDA) since 1898, but
simply collected germplasm with limited follow-up research. This PI
system is now part of the upgraded NPGS which is being expanded each
year. Seed of the accessions is given free upon reasonable request.
22 (over)
Next, enter biotech and the mass media, patents and lawyers...germplasm
becomes a sacred national heritage. No wonder that the Food and
Agriculture Organization (FAO) of the United Nations passes Resolution
9/83 to monitor operations and arrangementson germplasmcollection. A
classical socio-politicalconfrontation between developed and lesser-
developed countries was created (2). We must collect germplasm,
conduct research to improve it and provide the improved varieties for
production of food to feed people. The best possible science and
technology is used to do this...single-gene traits to introgressive
hybridization;backcrossingto trdnsgenic plants; etc. We run the risk
of famine, war, etc. should progressive science and research be
compromised.
BREEDING METHODS
The pedigree method is widely used to develop arrays of "eliten inbreds
of superior homogeneousphenotypes. Inbreedingdepression is a problem
with most open-pollinated species, so genotypic homozygosity is
avoided. For hybrid programs, elite inbreds are then tested for
combining ability in the variety developmentwork. Outstanding hybrid
performance is usually from general combining ability, but specific
combining ability is also important.
An elite germplasm "pooln is developed by a breeder after 10-20 years
of research. The backcrossmethod is often used to selectively add new
, simply inheritedtraits to an otherwise desirable elite inbred. Limited
use of recurrent selection schemes has been made for quantitative
traits.
HYBRIDS
The use of hybrid vigor in vegetable variety developmentwas initiated
in 1924 with sweet corn (Zea mays) hybrids by the Connecticut
Agricultural ExperimentStation. The genetic term for hybrid vigor is
heterosis. Heterosis may be defined in a practical way as a hybrid
performance greater than either parent for uniformity and/or economic
( yield. Since the 1940's, essentially all cross-pollinatedvegetable_'..
species have been converted from open-pollinatedto hybrid cultivars.
Today, there is a strong trend towards hybrid cultivars in self-
pollinated species'such as tomato, pepper and eggplant (3).23
Cytoplasmic-geneticmale sterility (CMS7 is widely used to produce
hybrid seed of onions (Allium ceDaT, carrot (Daucus carota), and table
beet (Beta vulqaris) (4-6). Current research efforts are aimed at
developing CMS cabbage, cauliflowerand broccoli (Brassic_oleracea7to
replace the current complicatedself-incompatibilitysystem for hybrid
seed production. French workers have also developed a CMS system for
radish (Raphanissativus).
Genic control of sex expression has been manipulated in the cucurbits
to condition dioecious, monoecious, etc., sex expressions which are
conducive to hybrid seed production (77. The best commercial example
is cucumber (Cucumis sativus). Possibly some million kilos of hybrid
cucumber seed is produced annually using gynoecious, all-female seed
parents crossed with monoecious pollen patents. Three or more major
loci are thought to control sex expression in cucumber (87. The same
phenotypes have been identified in cantaloupe, but the genetics are
different from cucumber and not well understood (g).
Plant growth regulators have proven useful in certain cases. Ethephon
is widely used for production of hybrid squash seed. Pistillate
flowering is induced temporarily on monoecious squash (Cucurbita
and C. moschata) by several applicationsfrom the one-leaf to _everal-
leaves stage of growth (107. There is evidence to suggest cthephon
might prove useful for hybrid cucumber and cantaloupe seed pr_ction
similar to squash. However, these two speciesare not so responsiveto
ethephon as squash. Moreover, monoecious lines are necessary for
successful inducting of pistillate flowering; and, determinant plant
types are more easily controlled than indeterminant. Silver
thiosulfate is commonly used to induce staminate flowering on
gynoecious cucumber seed parents for seed stock increases. Prior to
silver, gibberellicacid (GA7 was used for the same purpose. The AgS203
also induces staminatefloweringon gynoeciouscantaloupe seed parents,
whereas GA is ineffective.
24 (over)
Spinach (Spinaci_ oleracea) breeding research has elucidated a method
for hybrid seed production called sex reversal (SR). Two major loci
are thought to condition three different sex phenotypes. One of the
genotypes is nearly gynoecious with pistillate flowering until near
senescence whereupon staminate flowering provides pollen for
maintenance of the gynoecious line. The SR lines are used as seed
parents for hybrid seed production.
Genic male sterility (MS) has been observed by researchers since the
outset of plant breeding. There are more than 60 different genes
recorded in tomato (Lycopersiconesculentum)which condition MS. Tomato
researchers have identifiedm__ss35as one of the more desirable loci to
use in seed-parent line development. A marker gene for seedling
hypocotyl color is linked to ms35 which permits roguing at the seedling
stage. Pepper (Capsicum annum) MS has been reported by several
workers, but the work by INRA in France appears most promisingregards
hybrid seed production. Two loci for MS in cantaloupe (Cucumismelo)
were reported in the 1960's by USDA researchers in California,but have
not proven practical (10). Recent promising work was reported on
watermelon (Citrulluslanatus) seed production using genic MS linked
with a seedling marker for glacous leaves. Recessive single gene MS's
have been reported in Brassica oleracea and lettuce (Lactuca sativa),
but have not been useful to date.
COMMERCIAL PLANT BREEDING
We are in the business of manipulating genes to improve plant variety
performance for a profit. If it doesn't make reasonable profit, the
research is worthless. The focus must be on research to improve
economic performance starting with the seed production costs, to the
grower-shipper/processor-enduser. If any link in this sequence of
events is weak or broken,the new variety will likely fail.
The most importantprincipleof variety development is the equation:
P = G + E + (G x E)
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Phenotype is the sum of genotype, environment and genotype x
environment effects. The environment and interaction effects are
extremely importantin variety performance. Accordingly,new varieties
must be tested for performance in all markets before sales.
Developmental breeding must also be done in major production areas
unique from others, or where competition is keen in order to maximize
performance.
A second principle of variety development is the nSOS" rule, i.e.,
SCALE-ORGANIZATION-SCIENCE.No practical breeding programwill succeed
without large numbers of lines (genotypes) to evaluate, select,
recombine and inbreed (fix genetically). This effort must be organized
so valid conclusionscan be reached and made (decisions). Scientists,
support people and facilities,budgets, management are requirementsto
assure success. Science must be state-of-the-art(SOTA) to maximize
use of scale and organizationsin a competitivebusiness environment.
BIOTECH AND THE FUTUR_
Biotechnology is a new, and potentially powerful, tool to add to plant
breeding research programs (12). It can augment and/or accelerate
conventional variety development programs through (I) time saved, (2)
better products, (3) more genetic uniformity or (4) achieveresults not
possible by conventionalmeans.
The following concepts are being tested by private companies. This
list is not all-inclusive.
I. Cybridization - The hybridizing of cytoplasms from different
sources. The obvious application is related to cyto-male sterile
systems. This falls into either time saved or impossible by
conventionalmeans.
2. Cellular Screens - Methods to screen cells in a specific medium
for a specific reaction. The immediate applications are for
disease toxin resistanceand herbicide resistance (13).
26 (over)
3. Somaclonal Variatioq - By regenerating plants from single cells
through cell culture, new genetic variation is created. This
"new" genetic variation can be identified through either
conventional or biotech methods for incorporation into the
breeding research program. There are numerous examples of
somaclonal variation in the literature and in practice (14).
Current applications relate to disease resistance, processing
quality and seed producibility.
4. Anther Culture The cell culture of microspores to regenerate
haploid plants which are redoubledto form dihaploids. This
creates an "instant" inbred and saves the inbreeding time;
applicable to hybrid programs. In practice, this must be coupled
with several screens to eliminate undesirable genotypes/-
phenotypes. Otherwise, the plant breeder is quickly inundated
with hundreds to thousands of inbred lines to evaluate in the
conventional program. In practice, anther culture is used in
Brassica breeding with major research efforts in tomato. There
are many necessary pre-requisites to meet before it can be
commonly used in other species.
5. Transqenic Plants - this is the most difficult research area with
many pre-requisites to be satisfied prior to the actual gene
transfer. Gene identification,isolation,purification,transfer,
expression and regulation, all must be done successfully (15).
Recent reports on expression of the "bt" gene from Bacillus
thurinqensis in tomato plants are quite exciting. Other labs have
reported transfer of a virus gene to several plants species which
confers resistanceto that virus.
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SUMMARY
The area of commercial vegetablebreeding is dynamic and exciting (16).
There is no immediate "yield plateau" in sight. The area of biotech
promises to create even more opportunities for breeders to improve
varieties. We have seen resistance to certain diseases, insects and
herbicides via biotech in 1986/87. More and more "Hi-Tech" will be
used in the development of higher performing varieties. Research
developmentswhich have only been thought or dreamed about in the past
will become commonplace in the future. The proprietaryvegetable seed
business is coming of age in the USA and world. It is research-driven
which means vegetable breeder lead. Combined with the possibilities
from biotech, these are exciting times for commercial vegetable
breeding researchwith business opportunitiesfor profit.
NATLBRDS.PRS
MAY 1987
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SELECTED REFERENCES
I. Batcha, J.A. and J.A. Studebaker. 1983. A chronicle of plantvariety protection. Asgrow Seed Company. Kalamazoo, MI 49009. 26p.
2. Perlas, N. and J. Rifkin. 1986. Default at the gene banks. Garden10(3). NY Botanical Gardens, Bronx, NY.
3. Quagliotti, L. (Ed.). 1981. Symposium on vegetable and flower seedproduction.Acta Hort. 111. Castrocaro, Italy.
4. Jones, H.A. and A.E. Clarke. 1943. Inheritanceof male sterility inthe onion and the production of hybrid seed. Proc. Am. Soc. Hort.Science 43:189-194.
5. Hansche, P.E. and W.H. Gabelman. 1963. Digenic control of malesterility in carrots, Daucus carota L. Crop Science 3:383-386.
6. Bliss, F.A. and W.H. Gabelman. 1965. Inheritanceof male sterilityin beets, Beta vulqaris L. Crop Science 5:403-406.
7. Peterson, C.E. and J.L. Weigle. 1958. A new method of producinghybrid cucumber seed. MI Agr. Expt. Sta. Quart. Bull. 40:960-965.
8. Scott, J.W. and L.R. Baker. 1975. Inheritance of sex expressionfrom crosses of dioecious cucumber. J. Am. Soc. Hort. Science100:457-461.
9. Poole, C. and P. Grimball. 1939. Inheritanceof new sex forms inCucumis melo L. J. Hered. 30:21-25.
10. Coyne, D.P. 1970. Effect of 2-chloroethylphosphonicacid on sexexpression and yield in squash and its usefulness in producinghybrid squash. Hort. Science 5:227-228.
11. Bohn, G.W. and J.A. Principe.1964. A second male-sterilitygene inthe muskmelon. J. Hered. 55:211-215.
12. Brown, W.L. 1984. Genetic engineering of plants. National ResearchCouncil, Board on Agriculture.National Academy Press. Washington.p. 83.
13. Sun, M. 1986. Engineeringcrops to resist weed killers. Science231:1360-1361.
14. Evans, D.A., W.R. Sharp and H.P. Medina Filho. 1984, Somaclonaland gametoclonalvariation. Am. J. Bot. 71:759-774.
15. Goodman, R.M., H. Hauptli, A. Crossway and V.C. Knauf. 1987. Genetransfer in crop improvement. Science 236:48-54.
16. Innes, N.L. 1982. The potential from plant breeding for vegetablecrops. Sci. Horot. 33:60-66.
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EXHIBIT 1. Major Worldwide Vegetable Seed Companies
Asgrow(Upjohn)
- FerryMorse (LimaGraines)
- PetoSeed (GeorgeBall)
- NorthrupKing-Sluis& Groot(Sandoz)
- Harris-Moran-FMC(LaFarge)
- Arigenetics(Lubrizol)
- Sun Seeds-Dessert-Castle(U & F Seeds,Inc.)
- RoyalSluis
- IPB (Shell)
- Clause
- Takii
- Sakata
- 90% of WorldwideVegetableSeed Business.
30 (over)
EXHIBIT 2. Estimated Value Major Vegetable Species Worldwide (HI( =
millions).
- Onion $160/4/4 - Watermelon $ 60/4/4
- Tomato 135MM - Carrot 44MM
- Bean 125/4/4 - Cabbage 4OHM
Pea 110/4/4 Cantaloupe 30MM
- Cucumber gIMM - Lettuce 24MM
- Broccoli gOMM - SweetCorn 18MM
- Pepper 75MM - Squash 8MM
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ASGROWVEGETABLER & D
NOWFOR1995
I. INI'ROOUCTION
* Hybrids* PVP* CorporateInvestment/Participation.* MajorChanges
- Familyto Corp.Business.- PublicVarietiesto Proprietary.- ProprietaryR & D Investments.- Consolidation
* Germplasm- NPGS- FAO- LDC's
* BiotechHype.* Patentsand Lawyers.
II. COMMI_RCIALPLANTBREEDING
* Breedingfor a Profit.* P-G+E +GE* "SOS"Rule* AsgrowStatus
- People- Facilities- Budget- Results
* MajorPlayerin MajorMarkets.
III. BIOTECH
* UpjohnBiotechCommitment.* New Hi-TechTool.* IntegralPartof VarietyDevelopment.* Accelerate/AugmentMajorBreedingPrograms.* 1985for 1995,Lead-Time.* ExamplesCurrentResearch.
- Cybrids- DiseaseScreens- Dihaploids- Transgenics- ClonalSeeds
32 (over)
IV. FUIIJRE(Dynamic)
* GeneticVariation& Yield Plateaus.* More Hi-Tech.
* Asgrow's Place 1995.- Market Share Projections.- Now Research is 1995 Sales.
* Integration,People Chemistry...How?
V. CONCLUSION
Asgrow is positionedto be one of the "BIG 3".
LRBAKER5 JUNE 1987SAN DIEGO, CA
WRSCONF.INT
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