Nutritional and physiological studies on grapevine III

Abstract

Two vines each of uniform bearing Black Queen were dug up nine times during the period from April, 1954 to March, 1955, and leaves, shoots, stems, roots and berries were separately analysed for their contents of crude fiber, crude protein, soluble sugars and starch. Moisture in berries, crude fiber in fruiting shoots, canes, stems and roots, crude protein in leaves, and soluble sugars in berries were notably abundant, and starch was rich in canes, stems and roots. The contents of crude fiber and crude protein in berries, leaves and fruiting shoots increased with growth, the rate of increase being high up to the time of pit hardening, and thereafter the contents of soluble sugars as well as starch increased mark-edly. In older tissues such as canes, stems, and roots, contents of crude fiber and starch were low in the growing season (from March to November), and high in the dormant season (from December to February), while soluble sugar content was, on the contrary, high in the growing season and low in the dormant season. Little seasonal fluctuation of crude fiber was noticed in those tissues.