Eucalyptus Amplifolia and Corymbia Torelliana in the Southeastern USA: Genetic Improvement and Potential Uses

Donald L Rockwood,Phillip C Rucks,Patrick J Minogue,Romeo Jump,Dudley A Huber,Kyle W Fabbro,Gary R Hodge,Elizabeth Lamb,Mark A Crawford

doi:10.3390/f13010075

Donald L Rockwood, Phillip C Rucks + Show 7 more

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https://doi.org/10.3390/f13010075

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Journal: Forests	Publication Date: Jan 6, 2022
Citations: 3	License type: CC BY 4.0

Affiliation: University of Florida, North Carolina State University

Abstract

Eucalyptus amplifolia and Corymbia torelliana genetic improvement has been conducted in the lower southeastern USA by UF and collaborators since 1980. The collective accomplishments in genetic resources and potential commercial uses are summarized. For example, fast-growing, freeze-resilient E. amplifolia seeds are provided by 1st and 2nd generation seedling seed orchards (SSO) and a 2nd generation clonal seed orchard (CSO), while C. torelliana seed are available from 1st and 2nd generation SSOs. Breeding values (BV) have been developed for guiding the deployment of improved genotypes. Collaborative genetic improvement of these species is ongoing, including testing E. amplifolia in 11 countries and development of hybrid clones. Short Rotation Woody Crop (SRWC) systems may increase productivity and extend uses beyond conventional mulchwood to products such as medium density fiberboard (MDF), biochar, and energywood, while other possible applications include honey production, windbreaks, dendroremediation, and carbon sequestration. C. torelliana may be paired with E. grandis in two-row windbreaks to maximum windbreak effectiveness and may sequester as much carbon as E. grandis.

Highlights

Most Eucalyptus plantings in Florida before 1970 were windbreaks, ornamentals, and shade trees in central and southern Florida [1]
Reevaluation of a number of species starting in the 1970s [2,3] included tree improvement efforts with E. amplifolia and C. torelliana, which had been considered of limited potential and still are minimally deployed
The starting germplasm was derived from seed or trees resulting from earlier screening efforts, which resulted in the Florida Division of Forestry retaining and growing small quantities of E. amplifolia and C. torelliana for ornamental purposes

Summary

Introduction

Most Eucalyptus plantings in Florida before 1970 were windbreaks, ornamentals, and shade trees in central and southern Florida [1]. The 1st generation genetic base population included northern Florida and similar areas. The 2008 C. torelliana genetic base population (Table 1) included 960 trees from 29 trees in windbreaks in Florida. This tropical species has demonstrated tolerance to freezing. Twenty-five ment from [7].new Australian accessions were included in the 2nd generation base population that became TO12 These SSOs can supply seed for southern and central Florida. BVs have been developed for five E. amplifolia and five C. torelliana traits that are important for best deployment of genotypes (Table 3). The numbers of progeny tests contributing to these BVs were 15 in Florida and the southeastern USA for E. amplifolia and seven in Florida for C. torelliana.

Potential Uses

Research Needs

Findings

Conclusions