Scientific Reports of the Faculty of Agriculture, Okayama University
Published by the Faculty of Agriculture, Okayama University
ONLINE ISSN : 2186-7755


Asaoka, Katsuhiro
Imai, Shunji
Okamoto, Goro
In 'Muscat of Alexandria'grape berries,concentric cracking around the pedicel generally occurs in the time preceding harvest.In this experiment the effectds of vine shading and high moisture condition on the incidence in berry cracking were studied.The relationship of daily fluctuation of berry and trunk diameter with berry cracking was also investigated.Berry cracking incidence control vines was low.No cracked berries were observed on vines treated with shade only,while shade+high moisture treatment caused several cracked berries.Berries control vines showed contraction during day time and rapid enlargement from evening to early morning. The results suggest that phenomenon was mainly induced by leaf transpiration.Fluctuation of berry diameter in shade vines was insignificant while an expressive enlargement was recorded from evening to early morning in berries of vines treated with shade+high moisture.It appears that berry cracking occurs when low transpiration is coupled with water supply to roots,probably due to excessive absorption of water.Moreover,berry cracking occurred moistly in berries at the upper part of clusters,and cracked berries contained more sugar than non-cracked ones.A correlation between the shape of epidermal and hypodermal cells and berry crack was also observed.
berry cracking
'Muscat of Alexandria'
moisture supply