University of Florida

PLANT BREEDING IMPACTS ON FLORIDA COMMODITIES

Strawberry: This program directed by Drs. Vance Whitaker and Seonghee Lee at the Gulf Coast Research and Education Center (GCREC) at Balm, FL focuses on the identification of strawberry clones with high early yield, excellent flavor and shelf life, uniform appearance, and resistance to multiple diseases including anthracnose fruit rot and botrytis fruit rot. Florida is the major supplier of strawberries to the eastern US and Canada from late-November to mid-March, with a commercial acreage expanding to nearly 11,000 acres in 2013 and production value increasing to greater than $400 million. Three UF varieties, ‘Strawberry Festival’ and ‘Florida Radiance’ and Winterstar™ comprised nearly 90% of the Florida market in 2012-13. University of Florida varieties are popular in international markets as well and are currently grown in over 40 countries around the world.

Tomato:
Drs. Samuel Hutton and Tong Geon Lee co-direct the tomato improvement program located at the Gulf Coast REC at Wimauma, FL. The major research objectives of this program are related to developing breeding lines or finished hybrids with one or more of the following three attributes: 1. Improved yields, 2. Improved fruit quality, and 3. Multiple disease resistances. Heat-tolerant fruit setting is a major yield focus. Improved flavor along with high lycopene has been a major goal for fruit quality. Major disease resistances are to begomoviruses, bacterial spot, bacterial wilt, tomato spotted wilt virus, fusarium wilt race 3, and fusarium crown and root rot. Research emphasis has been placed on discovery of molecular markers linked to genes of interest for use in marker assisted selection (MAS). Releases of note are; ‘Solar-Set’ a heat-tolerant hybrid released in 1989, ‘Micro-Tom’ a miniature dwarf tomato released in 1989- widely used in molecular genetic studies around the world, Fla. 7547 resistant to fusarium wilt race 3 released in 1995, Fla. 7804 a fusarium wilt race 3 breeding line released in 2003, and Fla. 8153 (Tasti-LeeTM) a high lycopene hybrid with superior flavor released in 2006. Parental lines from this program are used by numerous private tomato breeding programs directly in varieties such as ‘Sebring’ and ‘Rocky Top’ or indirectly to produce commercial hybrids that dominate the fresh market tomato industry in Florida and other eastern states. The value of University of Florida germplasm to the Florida tomato industry could be conservatively estimated at $100 million per year for the last 20 years.

Blueberry:
The blueberry improvement program is located in the Horticultural Sciences Department at the University of Florida under the direction of Dr. Jim Olmstead. This program has used interspecific hybridization of native blueberry species from the southeastern United States with cultivated highbush blueberry to develop Southern highbush blueberry cultivars. These cultivars have made highbush blueberry production in subtropical Florida environments possible, and have allowed producers in Florida to market fresh blueberries when other production regions cannot.  The program uses recurrent selection to develop low chill, earlier ripening, blueberry cultivars with a high yield of excellent quality fruit. Additionally, new cultivars must exhibit tolerance to numerous disease, insect, and soil problems that limit survival and productivity of blueberries in the southeastern U.S. The program has released 34 Southern highbush blueberry cultivars since 1976, which account for more than 90% of all blueberries harvested worldwide during the months of April and October, and over 95% of the blueberry acreage in Florida. Among the most successful cultivars are ‘Star’, ‘Emerald’, and ‘Jewel’.

Small Grains:
The UF Small Grains breeding program, located at the North Florida Research and Education Center was under the direction of Ron Barnett until his retirement in 2005, and part-time continued effort until 2008. Dr. Ann Blount currently directs the small grain improvement program and Dr. Barnett continues his involvement in the program as an Emeritus Professor. In recent years, the Florida program has focused on developing triticale and oat cultivars for grazing and silage with an emphasis on forage quality, disease resistance and forage yield. This program has released over 35 cultivars with 19 new cultivars released since 1995. Cultivars released during the past three years include: Horizon 201 oat, RAM 99016 oat, and FL02011 a novel hulless oat. Recent releases of Monarch and Trical 342 triticale are now becoming popular as a southeastern dairy silage crops. Varieties from this program are significant contributors to the small grain acreage in the Southern US.

Peanut: The UF/IFAS peanut improvement program is currently directed by Dr. Barry Tillman at the North Florida REC at Marianna, FL. The peanut breeding program has focused on developing cultivars with improved yield, grade, disease resistance, nematode resistance, processing characteristics, and seed chemistry. Major diseases of emphasis are tomato spotted wilt virus, late leafspot, stem rot, CBR, and root knot nematodes. This program has released 16 cultivars since 1977.
The recently released cultivars ‘Carver’, ‘AP3', C-99R’, and ‘Andru II’ have excellent combinations of disease resistance, seasonal maturity, and high yields, and have been widely accepted by the industry. Three new “high-oleic cultivars with multiple disease resistance were released in 2006 (McCloud, York, and Florida 07).

Ornamental Plants - This program directed by Dr. Zhanao Deng at the Gulf Coast Research and Education Center in Wimauma, FL focuses on development and release of cultivars with novel colors or coloration patterns, enhanced container/landscape performance, improved disease resistance and stress tolerance, genetic sterility, or other characteristics that are of interest to the Florida environmental horticulture industry and gardeners. His research team also studies the patterns of inheritance of important horticultural or aesthetic traits, investigates their genetic bases, and develops new genetic, genomic and molecular tools that can be applied to ornamental plants. Accomplishments made by his research team include:
1. Discovery of sources of diseaseresistance and stress tolerance: sources of resistance to Pythium root rot, Fusarium tuber rot and Xanthomonas leaf spot in caladium, resistance to powdery mildew in gerbera and Coreopsis, and tolerance to low temperatures in caladium.  
2. Development and release of new cultivars:  Twenty-seven new cultivars have been released in caladium (13), gerbera (12), and lantana (2). 
3. Elucidating the inheritance of important characteristics,
including the inheritance of leaf shape, main vein color, color spots, and blotches in caladium, the inheritance of burgundy spots on Coreopsis flowers, the main genetic causes of male and female sterility in lantana, and patterns of pollen-mediated gene flow from Coreopsis tinctoria to Coreopsis leavenworthii, two important species of the Florida state wildflower Coreopsis.  
4. Development and application of biotechnological tools: Specific molecular markers for use in caladium, Coreopsis, gerbera, lantana, and petunia, and chromosome doubling techniques for use in caladium, eucalyptus, gerbera, ligustrum,
and nandina.  Application of these molecular markers has enabled identification of QTLs responsible for powdery mildew resistance in gerbera and discovery of multiple reproductive pathways in invasive lantana.

Forage Legumes and Grasses
: The overall forage improvement program at UF/IFAS is currently directed by Dr. Ann Blount at the North Florida REC at Marianna, FL with continued collaboration by emeritus professor Dr. Ken Quesenberry in the Agronomy Department at Gainesville. These programs have focused on red and white clover, alfalfa, rhizoma perennial peanut, and bahiagrass. Major selection criteria have included resistance to root-knot nematodes (RKN), fungal disease resistance, non‑dormancy, ploidy manipulation, and late fall - early spring vigor. The programs are also developing biotechnology applications for improvement of forage legumes including selection of in vitro regenerative genotypes in Arachis and Trifolium, and the use of molecular markers to evaluate genetic diversity among and within various species. Methods and techniques for genetic transformation of several of these species have been developed. Several new cultivars have been released by the forage breeding program including ‘Ocoee’ white clover – a RKN resistant cultivar selected from ‘Osceola’, which has been a major US white clover cultivar for over 15 years and is estimated to have been planted on almost 2.5 million acres. Two recent red clover releases include ‘Southern Belle’ a new non-dormant red clover for the lower Coastal Plains of the USA with very high levels of root-knot nematode resistance and ‘Barduro’ released in 2009 as a mid-dormant cultivar with high RKN resistance that is targeted for the upper Coastal Plains and the Piedmont regions. Riata bahiagrass was released in 2009 as a cultivar with improved early spring and late fall production, and commercial seed supplies are now available. Two new rhizoma perennial peanut cultivars ‘UF Peace’ and ‘UF Tito’ were released in 2009 having improved disease tolerance, good rates of cover and spread, and high forage yields. Commercial planting material became available in spring 2011.  Dr. Blount is also evaluating “dwarf type” bahiagrasses for potential use in utility turf applications.

Sugarcane: Sugarcane is the number one agronomic commodity in Florida based both on acres produced (400,000 acres in 2015) and value of production ($579,158,000 in 2014). The Florida sugarcane improvement program is a cooperative effort involving the USDA Sugarcane Field Station at Canal Point, FL, the UF/IFAS Everglades REC at Belle Glade, FL, and the Florida Sugarcane League, Inc. In this cultivar development program, Dr. Hardev Sandhu from the UF/IFAS collaborates with Drs. Jack Comstock, Duli Zhao, Per McCord, Vanessa Gordon and Muhammad Islam from the USDA, and Wayne Davidson from the Florida Sugar Cane League, to develop high yielding and disease resistant cultivars for organic and mineral soils in Florida. On an average, this program released approximately one cultivar per year, but due to high disease incidence in the commercially growing cultivars recently, we released 17 new cultivars in last three years (2013-2016). Cultivars developed by this program occupy more than 90% of sugarcane production in Florida and are also being used at numerous worldwide locations (Argentina, Belize, El Salvador, Guatemala, Honduras, Mexico, Morocco, Nicaragua, Senegal and Venezuela). The improved cultivars of sugarcane from this program have been responsible in large part for increasing sugar yields per acre by about 30% over the past 30 years (1985-2015).


Turfgrass:  The evaluation, selection, breeding, and subsequent recommendation of turfgrass species and cultivars have long been components of the University of Florida’s turfgrass research program.  To date the University of Florida has had involvement in the release of 17 cultivars of six different species. In the 1950s formal breeding programs at the University of Florida developed ‘Floratine’ St. Augustinegrass, the first improved variety resulting from these efforts.  ‘Floratam’ St. Augustinegrass was released in 1973 by G.C. Horn, A.E. Dudeck, and R.W. Toler. Chinch bug resistance helped to make Floratam the most important and widely used turfgrass released by the University of Florida.  Although no longer resistant to chinch bugs, Floratam is still the most popular St. Augustinegrass cultivar and accounts for over 40,000 acres annually or 69% of St. Augustinegrass sod production in Florida. Current research components in turfgrass breeding include contributions from three faculty positions: Dr. Kevin Kenworthy and Dr. Fredy Altpeter, Agronomy Department, Gainesville, FL, and Dr. Ann Blount, North Florida Research and Education Center, Marianna, FL. In addition, Dr. Ken Quesenberry, emeritus faculty, is currently working within the turfgrass breeding program. Efforts to improve turfgrass quality as well as tolerance to biotic and abiotic stress are underway in several warm-season species. Biotic stress research programs under the direction of Kevin Kenworthy and Ken Quesenberry include screening, breeding, and selection of 1) zoysiagrass for responses to sting nematodes, hunting billbugs, and large patch disease; 2) bermudagrass for sting nematode responses; 3) St. Augustinegrass for responses to nematodes, large patch, and chinch bugs; and 4) seashore paspalum for responses to dollar spot and caterpillars (fall armyworm and tropical sod webworm). Abiotic stress research programs involve the evaluation of shade and drought responses of zoysiagrass, St. Augustinegrass, and bermudagrass. The objective of the shade response program is simply to identify lines that are able to persist and spread under long-term shade. Drought responses are evaluated in a rainout shelter and uncovered field plots. The objectives are to identify those lines that are able to hold color and quality longer into the drydown period. This research involves graduate students and additional faculty from Environmental Horticulture and the West Florida REC.  Breeding for improved turfgrass quality is the focus of the turf-type bahiagrass program under the direction of Ann Blount, Fredy Altpeter, Ken Quesenberry, and Kevin Kenworthy. Bahiagrass accounts for 24% of the total sod produced in Florida.  The turf quality of bahiagrass, a low-input turfgrass, is limited by its open growth habit, light green color and tall seedheads. This program utilizes traditional, ploidy manipulation, mutagenic, and transgenic breeding approaches to enhance the turf quality of bahiagrass. Genetically improved sexual (diploid) and apomictic (tetraploid) bahiagrass plants are evaluated under controlled stress and field environments (transgenics under USDA-Aphis permit) to determine modes of reproduction and to identify lines with improved turf quality that still maintain the persistence of wild-type bahiagrass.

Ryegrass: Breeding of annual ryegrass began in the 1950s when T.E. Webb used mass selection to develop the annual ryegrass variety Florida Rust Resistant from local ecotypes, domestic varieties and plant introductions. Florida Rust Resistant was released by W.H. Chapman in 1962. In 1971, G.M. Prine discovered a reseeding stand of annual ryegrass ecotype near Kinderlou, Georgia. Four cycles of recurrent mass selection from a population composed of Kinderlou, Florida Rust Resistant, Magnolia, Gulf and some unknown reseeding ecotypes at Gainesville, Florida, resulted in the release of Florida 80 annual ryegrass in 1982. The crown-rust-resistant variety Surrey was released in 1989 and became another important variety. Through the 1990s the annual ryegrass breeding program, emphasized cooperative research between programs in Florida, Oregon and North Carolina. Crown rust resistance and adaptation to the Southeast was selected for in Florida. The Oregon plantings gave added disease resistance to stem rust and better seed production. Selections in North Carolina combined a cold-hardy, crown-rust-susceptible North Carolina Mountain ecotype with Florida’s best crown-rust-resistant breeding population. This resulted in the variety Florlina, jointly released by FAES and NCSU. The program cooperated with Ulf Feuerstein of Deutsche Saatveredelung in Germany to double the chromosomes of Surrey to produce a new tetraploid cultivar, Jumbo, which was released by FAES in 1997. The original Surrey cultivar was selected for two additional cycles to produce the variety Stampede in 1995.  Between 2001 and 2004, the annual ryegrass program focused on cooperative releases with commercial ryegrass seed companies with 19  releases (Fantastic, King, Surrey II, Ed, graze-N-Grow, Prine, Brigadier, Beefbuilder III, Striker, Attain, Bruiser, Stockage, Big Boss, + six numbered lines) licensed to commercial companies. Beginning in 2006 Kevin Kenworthy assumed leadership of the annual ryegrass breeding program at Gainesville and Ann Blount also began a program of selection in north Florida at Marianna.  Seven additional cultivars (Ocala, Angus I, + 4 numbered lines) were jointly released by Kenworthy and Prine in 2006 from the Gainesville program and in 2010 Blount released Earlyploid from the Marianna program. Two additional cultivars (experimental designations, FL PE and FL Red, were released in 2016 and 2017, respectively and commercial production licenses are currently being negotiated. Diploid and tetraploid annual ryegrasses developed in Florida now dominate the improved seed trade of Pacific Northwest grown annual ryegrasses.  Future improvement research will focus on use of genomic and traditional selection for enhanced disease resistance, variable maturity dates, and seasonal distribution of dry matter yields.


Tree Fruits and Nuts:
The tree fruit and nut breeding effort at the University of Florida was initiated by Dr. Ralph Sharp with an emphasis on development of adapted low chill fruit and nut varieties. Dr. Wayne Sherman led the program from 1975 until his retirement in 2003, and since that time the program has been led by Dr. José Chaparro. Overall the program has released approximately 50 peach and nectarine and 5 plum varieties. In addition, the low chill apple, pear, and pecan varieties, ‘Tropicsweet’, ‘Floridahome’, and ‘Moreland’ have also been released by the program.  The program has had a major impact in the subtropics with the publicly available stone fruit varieties being grown in over 30 countries worldwide. Plant variety patents have been obtained for 11 peach, 4 nectarine and 3 plum varieties. The newer patented varieties are grown commercially in licensee countries such as Republic of South Africa, Egypt, Morocco and Australia.

Forest Trees: The forest tree breeding effort at the University of Florida (UF) was initiated in 1954 by Dr. Tom Perry working within the Cooperative Forest Genetics Research Program (CFGRP).  Under subsequent directors Drs. Ray Goddard, Tim White, Dudley Huber, Gary Peter, and Matias Kirst, the CFGRP has steadily improved slash, loblolly, longleaf, and sand pines for private and public planting in Florida and the lower Southeast. Since continuing a Eucalyptus tree improvement program begun in 1966 by the US Forest Service and several industrial and private cooperators, Dr. Donald Rockwood has improved the growth, tree form, and freeze resilience of E. grandis, E. amplifolia, E. camaldulensis, and E. tereticornis for planting in Florida and similar regions. UF/IFAS has released E. grandis varieties G1, G2, G3, G4, and G5, which are among the most freeze resilient E. grandis worldwide.