ウイルスフリー化した’グローコールマン’樹の果実の成熟特性

The Grape cultivar 'Gros Coleman'(Vitis vinifera)is the latest-maturing variety in japan,mainly cultivatde in green-houses in southern Okayama.Vines treated with virus-free treatments before raising in a nursery bed have been introduced in the last desade to improve the fuit quality,especially skin coloration and sugar content.However,some growers feel that the fruit taste from treated vines tends to deteriorate earlier than from untreated vines. We investigated change in the qualities of the berries produced on treated and untreated vines from October to January.After analysing skin color,berry turgidity,and juice constituents,we concluded that the palatability of berries on virus-free vines might be lessened in late December or thereafter of the rapid decrease in amino acids such as glutamic acid,glutamine,and alanine,which considerrably affects fruit taste.