Location: Subtropical Horticulture Research2018 Annual Report
Objective 1: Efficiently and effectively maintain the safety, genetic integrity, health, and viability of subtropical and tropical ornamental genetic resources, and distribute them and associated information worldwide. Subobjective 1A: Strategically expand and improve collections of priority tropical and subtropical ornamental taxa and associated information. Subobjective 1B: Conserve, regenerate, and distribute as needed subtropical and tropical ornamental genetic resources and information efficiently and effectively, emphasizing priority genera identified by Crop Germplasm Committees (CGCs). Objective 2: Develop more effective genetic resource characterization, phylogenetic analyses, and evaluation methods, and apply them to priority subtropical and tropical ornamental genetic resources. Record and disseminate evaluation and characterization data via GRIN-Global and other data sources. Subobjective 2A: Develop nearly complete whole plastome and low copy nuclear gene sequences to generate well-resolved phylogenies of various clades of Amaryllidaceae. Subobjective 2B: Elucidate the genetic control of anthocyanin pigmentation in the genera Hippeastrum (amaryllis), Worsleya, and Griffinia, and fragrance production in Hippeastrum. Objective 3: Guided by new knowledge of the genetic relationships and valuable ornamental traits of poorly-known plants, develop superior new cultivars and genetically-enhanced populations and/or selections of priority subtropical and tropical ornamental crops. Subobjective 3a. Select, breed, and/or release new cultivars of the subtropical/ tropical shrub Portlandia, the flowering tree genus Tabebuia (inc. Handroanthus), and other tropical/subtropical taxa. Subobjective 3b: Continue evaluation and selection of Hippeastrum hybrid progeny.
The long term objectives of this project are to ensure a secure and diverse stream of new genetic variation and enhanced germplasm for the subtropical/tropical ornamental horticulture industry as well as generate and consolidate detailed information about the intrinsic genetic variability, systematic relationships, and ornamental merit of genetic resources via genetic characterization, systematic studies, and field evaluation. These objectives are a combination of hypothesis-driven and non-hypothesis driven research. The objectives form an integrated program of subtropical/tropical ornamental germplasm characterization, enhancement and improved management practices. The program efficiently and effectively maintains the safety, genetic integrity, health, and viability of subtropical and tropical ornamental genetic resources. Collections of priority tropical and subtropical ornamental taxa and associated information will be strategically expanded and improved, distributing them worldwide to customers and stakeholders, emphasizing priority genera identified by appropriate Crop Germplasm Committees. Nearly complete whole plastomes and many low copy nuclear gene sequences will be obtained to generate well-resolved phylogenies of various clades of Amaryllidaceae. The genetic control of anthocyanin pigmentation in the genera Hippeastrum (amaryllis), Worsleya, and Griffinia, and fragrance production in Hippeastrum will be elucidated. Guided by new knowledge of the genetic relationships and valuable ornamental traits of poorly-known plants, superior new cultivars and genetically enhanced populations and/or selections of priority subtropical and tropical ornamental crops will be developed, with emphasis on the tropical shrub Portlandia, the flowering tree genus Tabebuia (inc. Handroanthus), and other tropical/subtropical taxa. The evaluation and selection of Hippeastrum hybrid progeny will be continued. Hybrid progeny from the past few years, many of which are just reaching flowering size, will be evaluated for floral phenotype and flowering behavior, with selections made based on novel flower coloration, patterning, fragrance, and both bud and scape number.
This report documents progress for Project Number 6038-13210-003-00D, which started in February 2018 and continues research from Project Number 6038-13210-002-00D, entitled “Genetic Characterization, Genetic Improvement, and Best Horticultural Management Practices for Subtropical/tropical Ornamental Germplasm.” We have received the data from our genome scan of 120 samples of Amaryllidaceae. We are in the process of extracting plastome data from the raw data. In the nuclear data set, we obtained 1,500 loci with coverage across our samples of >70% and another 2,500 <70%. We received approval from the Office of Technology Transfer for public domain release of 15 amaryllis hybrid cultivars through the National Plant Germplasm program.
1. From the amaryllis breeding program at ARS-SHRS, Miami, Florida, approval and release of 15 Hippeastrum x hybridum cultivars was accomplished. The 15 cultivars each have novel characteristics that have not been observed in current commercial varieties. The releases will be provided to commercial nursery producers who request material for production, propagation and further breeding. Material has been requested by two commercial growers in Florida already. The release of these varieties will expand the current availability of high quality amaryllis hybrids for the commercial trade, and lead to the expansion of domestic production of this important crop.