Biological features of common persimmon (Diospyros virginiana L.)

Abstract

The article presents the results of long-term observations on the biology of common persimmon. Both positive and negative properties of this specie are given. Phenological indicators are provided: bud swelling, appearance of the first leaves, budding, flowering, fruit ripening. Diospyros virginiana L. is a hexaploid (2n = 90), however, it should be noted that along with the hexaploid race there is also a tetraploid one (2n = 60). Plants of this species are mainly dioecious, the flowers are bisexual. The flowering phase takes place in the first decade of June, which is one to two weeks later than that of the Eastern and Caucasian persimmons. The percentage of useful ovary is quite high and makes 27-29%. The fruit is smaller in size than the eastern persimmon, but three to four times larger than the Caucasian one. They have a spherical or conical shape, ranging in size from two to five cm in diameter. In a solid state, the fruits are very tart, but ripe fruits are very sweet, the sugar content reaches 20%. The ripening period is one and a half months. The number of seeds in the fruits is three to five pieces, they are larger in comparison with the seeds of the Caucasian persimmon. Diospyros virginiana L. is mainly found in the wild in the USA, where it is used as a rootstock on heavy, swampy soils for cultivated varieties of eastern persimmon, as it easily tolerates the proximity of groundwater, temporary flooding and river floods. In the Russian Federation, it is practically not used, since it is inferior in yield to plants grafted on Caucasian persimmon and forms a lot of growth. A great advantage of the common persimmon is its winter hardiness, it is much higher than that of cultivated varieties. It tolerates a drop in temperature to minus 25–280 С without any damage. In breeding, it is used to obtain varieties with high frost resistance to expand the cultivation area and move to more northern regions.