Shonan Gold


Shonan Gold is a hybrid Japanese citrus, with a characteristic "golden" bright yellow color.
Though not completely seedless, the seeds are few in number. The yellowness is inherited from its mother plant, a small-sized variety known as Ōgonkan or "Golden Orange", which has been crossed with the Imamura unshiu variety of satsuma orange for size and other desired traits. The cultivar was developed by an agricultural experiment station run by the Kanagawa Prefecture.

History

Shōnan gold was first cultivated in 1988, by hybrid crossing the Citrus flaviculpus with Citrus unshiu cv. Imamura unshiu. It is thought to be a nucellar seedling of the mother plant Ōgonkan.
The cultivation was first conducted at the Kanagawa Agricultural Research Institute, Nebukawa Experiment Station in the city of Odawara, although the station has since been bureaucratically reorganized as the Nebukawas Sub-Office, under the Ashigara-ku Office, Kanagawa Agricultural Technology Center. Further seed selection and propagation was continued until the 12th year to establish stability of characteristics. The hybrid was registered with the name "Shōnan Gold" at Japan's Ministry of Agriculture, Forestry and Fisheries in 2003, and the first harvest took place that same year. Shipment started in 2006 with about 2.0 metric tons officially entering the market, or about 450 kg according to a newspaper coverage.

Description

The sphere-shaped fruit averages about 77 g each in weight and the rind or peel is yellow. The flesh or pulp is tender, succulent, and sweet, with sugar concentration at 11~12 deg. Bx. It is fragrant like the Ōgonkan, but is smoother-skinned and easier to peel by hand. The fruit ripens during April and retains excellent flavor until May, which exactly targets the months when the unshū oranges run scarce in the Japanese market.

Cultivation

The young sapling is thorny and grows upright, but as it ages, it loses its thorns and begins to spread its limbs laterally. To encourage earlier fruiting, it is important to the branches on the young tree so they fan out. Fruiting is bountiful, but has alternate year bearing tendencies.
The growers and the agency jointly held a symposium on the proper method of fruit thinning and planted a test tree, to continue to develop improved cultivation techniques and quality.

Crop yields

The history of planted acreage, annual yields, and shipments, according to the agriculture ministry data are tabulated below.
In statistics up to 2010, Kanagawa prefecture accounted for 100% of Shonan Gold production in Japan. The major producers are the city of Odawara and the town of Yugawara.
FYAcreageCrop yieldsShipments
20050.9ha2.2t2.0t
20060.9ha2.2t2.0t
20072.7ha8.8t8.0t
20083.7ha11.0t10.0t
20093.9ha31.1t30.0t
20093.9ha31.1t30.0t
20105.7ha41.6t40.0t

The year is fiscal year, so the first shipment, given as FY2005 in the above data, really occurred in 2006. According to an Asahi Shimbun online edition, the first shipment amounted only to 450 kg.

Gallery

Explanatory notes