1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter?
Diverse germplasm resources (breeding lines, cultivars, landraces, wild species relatives, etc.) exist for enhancement of cultivated crop plants. Genes that may be valuable for crop improvement are often not well characterized, associated with undesirable traits, or difficult to effectively transfer to adapted cultivars or breeding lines due to low heritability and/or the presence of numerous genes, all of which are important to achieve the intensity of expression exhibited in the unadapted plant materials. The underlying genetic bases of key horticultural traits in major Solanaceous fruit crops – tomato and pepper - will be elucidated, and will facilitate their deployment in improved germplasm. This project focuses on the genetic characterization and enhancement of attributes that influence quality, nutritive value and marketable yield of fresh and/or processed products. The specific objectives are:.
1)Development of tomato germplasm with enhanced quality attributes including fruit firmness and carotenoid pigments and characterization of the genetic control of these attributes. Fruit firmness and color contribute to tomato product quality and nutritive value. .
2)Identification of molecular markers linked to genes that influence resistance to tomato fruit rot caused by the anthracnose pathogen. Resistance-linked markers would facilitate development of resistant germplasm, thus reducing losses in yield and product quality. .
3)Development of new pepper germplasm for culinary and ornamental applications; characterization of the inheritance and genetic control of anthocyanin pigment accumulation in pepper fruit, flower and leaf tissue. The research will facilitate development of new pepper cultivars for diverse market applications.

Improvements in complex traits or traits with low heritability have lagged considerably and are often characterized by little or no progress or small incremental gains. This research is needed to determine what genes are most valuable, and efficiently transfer those genes in order to develop new germplasm containing those traits. New enhanced germplasm will reduce risks of production loss, lessen the need for chemical controls, address the needs of consumers who increasingly demand more nutritious products and improved product quality, and provide new value-added crops for growers faced with low profit margins. The research is relevant to public and private crop improvement programs that focus on cultivar development and basic research relevant to crop improvement.

This research is directed towards the genetic improvement of horticultural crops which contributes to the Plant, Microbial and Insect Genetic Resources, Genomics, and Genetic Improvement National Program 301 (100 percent); Research Component II. Genomic Characterization and Genetic Improvement. Diverse genetic resources are utilized to improve commodity fresh and processing market quality, nutritive value, and to reduce the need for chemical control of disease and crop loss that occurs during production, processing, distribution, and storage.

2.List by year the currently approved milestones (indicators of research progress)
Year 1 (FY 2004)

Complete year 1 tomato fruit firmness evaluations of diallel population constructed to evaluate the contribution of firmness from different germplasm sources.

Complete molecular marker screening of a recombinant inbred line (RIL) population developed to identify quantitative trait loci (QTL) for anthracnose resistance.

Release pepper germplasm with improved ornamental/culinary attributes.

Identify GenBank sequences with homology to anthocyanin-related genes.

Year 2 (FY 2005)

Complete year 2 tomato fruit firmness evaluations and determine heritability of firmness indices.

Develop populations for genetic studies of tissue-specific carotenoid accumulation in tomato.

Complete QTL analysis of tomato anthracnose resistance.

Identify structural and regulatory genes responsible for tissue-specific pigmentation in pepper.

Year 3 (FY 2006)

Conduct inheritance studies of tissue-specific carotenoid content in tomato.

Map genomic regions associated with tomato anthracnose resistance.

Identify structural and regulatory genes responsible for tissue-specific pigmentation in pepper. Year 4 (FY 2007)

Release genetic stocks with unique firmness and carotenoid pigmentation.

Release pepper germplasm with novel ornamental or dual purpose ornamental/culinary attributes.

Develop pepper populations for inheritance studies of fruit and leaf anthocyanin pigmentation.

Develop selectable markers for tissue-specific anthocyanin accumulation in pepper.

Year 5 (FY 2008)

Characterize carotenoid-related gene expression in tissues of differentially pigmented tomato genotypes.

Evaluate sequence homology in carotenoid genes from contrasting genotypes.

Assess utility of QTLs for anthracnose resistance in marker assisted selection.

Conduct inheritance studies of tissue-specific anthocyanin accumulation in pepper.

Develop selectable markers for tissue-specific anthocyanin accumulation in pepper.

4a.List the single most significant research accomplishment during FY 2006.
Pepper anthocyanin gene regulation. Color attributed to anthocyanins contributes to product sensory quality attributes, potential nutritive value, and plant stress response. A Capsicum line we have developed, 02C27, accumulates anthocyanin in various tissues and accumulation is markedly sensitive to environmental stress. Real-time PCR analysis of tissues that varied in anthocyanin pigmentation intensity in response to environmental conditions and virus infection revealed functional but differentially expressed structural genes in the anthocyanin biosynthetic pathway. Likewise, analysis of three transcription factor encoding genes demonstrated differential expression of these regulatory elements, coincident with anthocyanin accumulation. The results are important for identification of key regulatory elements that influence anthocyanin accumulation and improved pigmentation. This research is cooperative with the ARS Floral and Nursery Products Research Unit in Beltsville. A Specific Cooperative Agreement established with Virginia Polytechnic Institute and State University, Blacksburg, VA, focuses on transcription factor protein interactions in order to characterize mechanisms of gene regulation. (Action Plan Component II, Problem Area IIa; ARS Strategic Plan Goal 1, Objective 1.2, Subobjective 1.2.6 and 1.2.7).

4b.List other significant research accomplishment(s), if any.
Tomato fruit firmness. In a cooperative project with the ARS Produce Quality and Safety Laboratory in Beltsville and Ohio State University to broaden a narrow genetic base for fruit firmness, we have evaluated fruit firmness in lines of varying genetic background with firmness derived from the wild tomato relatives Lycopersicon cheesmanii and L. pimpinellifolium. Our previous research indicated that fruit puncture and fruit compression accounted for varying aspects of fruit firmness and that firmness of parental lines was generally a good predictor of hybrid firmness. New research has examined relationships between fruit fresh and dry weight and firmness and resulted in identification of breeding lines which combined acceptable fruit fresh weights with superior firmness. We demonstrated that fruit compression was a superior selection indice for firmness in comparison to fruit puncture in a breeding program for combining fruit firmness with large fruit size. Inbred backcross populations derived from divergent parents will facilitate identification of new genes for enhancement of fruit firmness. (Action Plan Component II, Problem Area IIb; ARS Strategic Plan Goal 1, Objective 1.2, Subobjective 1.2.7 and 1.2.8).

New pepper germplasm. New pepper germplasm is needed to enrich the commercial pepper gene pool which lacks diverse new cultivars to meet market demands for novel culinary, ornamental, and dual-purpose cultivars. Utilizing the rich genetic diversity available in pepper landraces and related species, new pepper ideotypes with novel fruit, foliage, and plant growth habit have been developed. Five selections have been advanced for 2006 commercial evaluation and release as culinary/ornamental cultivars. Novel peppers have the highest per unit value of any pepper product and have become a profitable crop for greenhouse pot plant and transplant production and an innovative way for small farmers to produce a high value alternative crop. This research is collaborative with the ARS Floral and Nursery Products Research Unit in Beltsville and two industry partners and has resulted in establishment of a new Collaborative Research and Development Agreement (CRADA) between ARS and our private partners. (Action Plan Component II, Problem Area IIb; ARS Strategic Plan Goal 1, Objective 1.2, Subobjective 1.2.8).

4c.List significant activities that support special target populations.
None.

4d.Progress report.
None.

5.Describe the major accomplishments to date and their predicted or actual impact.
The start date for this project was 07/24/2003. Considerable untapped genetic diversity exists in wild relatives of tomato to enhance the nutritive value of cultivated forms of the crop. Utilizing an accession of the wild tomato relative L. cheesmanii, genes that influence fruit carotenoid content were transferred to the cultivated tomato to enhance fruit nutritional content. Two cherry tomato breeding lines designated 02L1058 and 02L1059 that produce fruit with high levels of the carotenoid beta-carotene were released by ARS for use in the development of specialty hybrids. High beta-carotene cherry tomato cultivars are presently not available in the marketplace. Beta-carotene can be synthesized to vitamin A and is an essential nutrient. Analysis of chemical constituents and taste panel evaluations indicated that fruit quality of these lines was equal or superior to conventional cultivars containing little beta-carotene. Seed of these breeding lines has been distributed upon request to public and private breeders for research purposes, including development and commercialization of new cultivars. (Action Plan Component II, Problem Area IIb; ARS Strategic Plan Goal 1, Objective 1.2, Subobjective 1.2.8).

Genes from diverse wild species are known to influence tomato fruit firmness but have not been adequately evaluated to broaden the narrow genetic base for fruit firmness. A uniform measure of firmness is also lacking. Utilizing breeding lines developed from crosses with the wild tomato species Lycopersicon cheesmanii and L. pimpinellifolium, a collaborative project between scientists from the Vegetable Laboratory, Produce Quality and Safety Laboratory, and Ohio State University evaluated fruit firmness in lines of varying genetic background using a number of firmness measures. Analysis of tomato fruit firmness indicated that different measurement parameters account for varying aspects of fruit firmness. Firmness derived from firm-fruited parents can generally be transferred to superior breeding lines and there is little deviation from the predicted performance among firm donor parents. The analysis also indicated little influence of planting location on firmness. Our results demonstrate that genes for fruit firmness can be predictably transferred to commercially acceptable material and that selection of lines with superior firmness may be economized in one production location. (Action Plan Component II, Problem Area IIb; ARS Strategic Plan Goal 1, Objective 1.2, Subobjective 1.2.7 and 1.2.8).

New pepper germplasm is needed to enrich the commercial pepper genepool which lacks diverse new cultivars to meet market demands for novel ornamental, culinary, and dual-purpose cultivars. Utilizing the rich genetic diversity available in pepper landraces and related species, a new award winning pepper cultivar named ‘Black Pearl’ was developed and released. ‘Black Pearl’ was developed for ornamental use and bears distinctive black foliage and bright red upright clusters of small round fruit. ‘Black Pearl’ is a product of a Collaborative Research and Development Agreement between the ARS, BARC Vegetable Laboratory and Floral and Nursery Products Research Unit and an industry partner to tap genetic diversity in Capsicum species for development of new pepper cultivars with novel fruit, foliage, and plant growth habit. ‘Black Pearl’ was designated an All-America Selections (AAS) Flower and Vegetable Award Winner. Ornamental peppers have the highest per unit value of any pepper product and have become a profitable crop for greenhouse pot plant and transplant production and an innovative way for small farmers to produce a high value alternative crop. (Action Plan Component II, Problem Area IIb; ARS Strategic Plan Goal 1, Objective 1.2, Subobjective 1.2.8).

Model systems have long been available for studying biochemical and genetic aspects of anthocyanin pigmentation in plants. Despite these systems, our knowledge concerning regulation of the biosynthetic pathway and the action of regulatory genes that modify gene expression is limited. A series of experiments conducted under controlled environmental conditions has identified the key regulatory step controlling anthocyanin accumulation in pepper. Light and temperature were demonstrated to have a marked effect on gene expression. The results provide fundamental information to characterize the genetic control of anthocyanin accumulation in pepper and understand how environmental factors modulate gene expression. (Action Plan Component II, Problem Area IIa; ARS Strategic Plan Goal 1, Objective 1.2, Subobjective 1.2.6 and 1.2.7).

6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products?
A 2006 All America Selections (AAS) award winning ornamental pepper cultivar named ‘Black Pearl’ has been licensed to a Collaborative Research and Development Agreement (CRADA) partner. An application for Plant Variety Protection has been submitted.

A new CRADA was signed to conduct research on the genetic control of anthocyanin accumulation and develop ornamental and dual purpose ornamental/culinary pepper germplasm. The CRADA is cooperative between the Vegetable Laboratory, Floral and Nursery Products Research Unit, and two private partners. This CRADA succeeds a CRADA whose terms were completed in 2003.

An exhibit highlighting the release of our ornamental pepper cultivar ‘Black Pearl’ was presented at the Mid-Atlantic Nursery Trade Show held in Baltimore, MD, January 11-13, 2006.

A talk entitled “Use of Pepper as an Ornamental Cut Crop” was presented to growers at the University of Maryland Summer Growers Symposium held in Waldorf, MD, July 18, 2006.

7.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below).
Staub, J. 2006. Capsicum annuum ‘Black Pearl’: A pepper that looks almost too good to eat. Fine Gardening. 110 (July/August):16.

Onofrey, O. 2006. Best of 2005, Top five performers. Greenhouse Grower. 24 (January): 42-56.

Brown, C. 2006. Edible harvest: Vegetable selections for 2006. Washington Gardener. January/February issue, p. 18-19.

White, J.D. 2005. Standing Trial, GrowerTalks. October issue, p. 54-80.

Around your garden. Southern Living. July, 2006. p. 1-3.

McGinnis, L. 2006. Black Pearl: Beauty with a bite. ARS News, April 26, 2006.

Review Publications
Stommel, J.R., Bosland, P.W. 2006. Ornamental pepper, Capsicum annuum. In: Anderson, N., editor. Flower Breeding and Genetics: Issues, Challenges and opportunities for the 21st Century. Dordrecht, The Netherlands: Springer. p. 561-599.