Patent Application
20160128253
Citrus sinensis L. Osbeck
‘N13-32’
The present invention relates to a new and distinct early season clone of ‘Hamlin’ sweet orange with improved juice color and typical or better soluble solids for processing named ‘N13-32’. ‘N13-32’ is a somaclone (protoclone, meaning regenerated from protoplasts) regenerated from protoplasts isolated from an embryogenic suspension culture of standard ‘Hamlin’ (Citrus sinensis L. Osbeck) in 1989. Somaclonal variation is defined as variability in plants regenerated from tissue culture that is either induced or uncovered by a tissue culture process. Most somaclonal variation is negative, but if enough plants are examined, positive changes can usually be recovered. Somaclonal variation has been a primary source of genetic variation in sweet orange exploited in citrus improvement programs (Grosser et al. 2007). Hamlin ‘N13-32’ is the first of three superior ‘Hamlin’ somaclones selected for release from more than 500 somaclones under evaluation. The first asexual reproduction of ‘N13-32’ involved grafting of the original ‘N13-32’ tree onto ‘Swingle’ citrumelo rootstock and planting in the Citrus Research and Education Center (CREC) North-40 Block 16 in 1991 in Lake Alfred, Fla. Vegetative budwood of ‘N13-32’ was subsequently cut from the tree and successfully grafted onto ‘Swingle’ in 2002 in Lake Alfred, Fla. The resulting tree is the only existing 2nd generation tree of ‘N13-32’ and has demonstrated true-to typeness.
‘N13-32’ was one of three original ‘Hamlin’ somaclones selected for improved juice color with typical or better soluble solids, based on several years of juice quality data (Table 1). Selection of improved Hamlin clones has proven to be quite difficult due to extreme variability in clonal juice quality data from year to year (unlike ‘Valencia’). Improved color of ‘N13-32’ was noticed during the first two years of fruiting (1995-1996). Of the three original ‘Hamlin’ somaclones evaluated, ‘N13-32’ was selected because it was the first of more than 500 clones evaluated that produced a juice color score higher than 36 in December fruit in a pasteurized juice sensory evaluation (Table 2). The minimum required color score for grade A juice is 36. Traditional clones of ‘Hamlin’, the predominant early season processing orange in Florida, generally produce juice with a color score of around 34, and require blending with other darker colored juice to reach grade A status. Thus, a higher colored clone provides many advantages to the growing NFC (not from concentrate) business. ‘Hamlin’ clone ‘N13-32’ is also maintaining tree health better than adjacent ‘Hamlin’ clones in the test block that is now being impacted by Huanglongbing (HLB) disease.
‘N13-32’ is illustrated by the accompanying photographs, which show the tree's form, foliage and fruit. The colors shown are as true as can be reasonably obtained by conventional photographic procedures. The photographs are from the original tree (approximately 20 years of age).
Phenotypic Description of Citrus sinensis L. Osbeck ‘N13-32’
The following detailed description sets forth the distinctive characteristics of ‘N13-32’. The present botanical description is that of the variety grown as a 16 year-old tree growing on ‘Swingle’ rootstock in Lake Alfred, Fla. The colors (except those in common terms) are described from the R. H. S. Colour Chart published by The Royal Horticultural Society in London (second edition), in association with the Flower Council of Holland.
