Actinidia


Actinidia is a genus of woody and, with a few exceptions, dioecious plants native to temperate eastern Asia, occurring throughout most of China, Taiwan, Korea, and Japan, and extending north to southern areas of Russian Far East and south into Indochina. The genus includes shrubs growing to tall, and vigorous, strong-growing vines, growing up to in tree canopies. They mostly tolerate temperatures down to around, and some are much hardier.
The leaves are alternate and simple, with a dentated margin and a long petiole. The flowers are solitary or in axillary cymes, usually white, with five small petals. Most of the species are dioecious with separate male and female plants, but some are monoecious. The fruit is a large berry containing numerous small seeds; in most species, the fruit is edible. In particular, this genus is known for the species Actinidia deliciosa, one of the most common cultivated kiwifruits, and for the hardy ornamental A. kolomikta.

Fossil record

Actinidia macrofossils have been recovered from the late Zanclean stage of Pliocene sites in Pocapaglia, Italy.

Species

The 40–60 species of Actinidia include:

Uses

Kiwifruit is a cultivar group of A. deliciosa, and hardy kiwi is the species Actinidia arguta, which has small fruit weighing, with green edible skins and green flesh; it is hardier than A. deliciosa. Some species are grown as ornamental plants, notably A. kolomikta.
In Japan, Actinidia polygama is noted for having an effect on cats much like that of catnip. It is mentioned in the saying 猫にまたたび、女郎に小判, meaning to put someone in a good mood by providing that which they most desire.
A. kolomikta is the hardiest species, and has distinctive white- and pink-variegated foliage even on wild plants, an unusual phenomenon. Its fruit is very small, weighing or less.

Etymology

Actinidia is derived from Ancient Greek 'ray', and is a reference to the rayed styles of the flowers.