論文ID: SZD-061
Picking excess berries is essential to obtain high-quality bunches of table grapes. However, this process requires significant labor within a short period, so labor-saving techniques are needed. We observed that the number of flowers per inflorescence was significantly reduced when 250 μL of 10%–15% trehalose was injected into the buds of ‘Shine Muscat’ using a microsyringe. Both the number of peduncles and the numbers of flowers on tip peduncles tended to decrease, showing that the synergistic effect of these two factors reduced the numbers of flowers in the inflorescences. However, a significant reduction in the number of flowers was observed only when trehalose was injected into buds with a vertical diameter of 10 to 15 mm, indicating that trehalose is effective only within a very limited time frame. To assess the degree of labor saving, we evaluated the time required for berry thinning by combining trehalose injection with two methods of cluster shaping: the conventional method and a labor-saving method. In the conventional method, we cut the peduncles with scissors and retained the main tip of the cluster at 4 cm, whereas in the labor-saving method, we cut the main axis of the rachis with scissors and used wing or lateral peduncle lengths of 4 cm. The average time required to pick berries from trehalose-treated grapes was significantly shorter (36.3 s) compared with untreated grapes. When scaled to 10 a (3,000 bunches), the combination of the conventional method and trehalose injection reduced the labor time required by approximately 40.3 h, while the labor-saving method combined with trehalose injection reduced labor time by approximately 100.3 h compared with conventional cultivation. The trehalose injection process required approximately five seconds per bud. Assuming injection of 6,000 buds on 3,000 shoots over 10 a, this would take an estimated 8.3 h. Thus, trehalose injection is an effective option even when accounting for the labor involved in the injection process. In addition, the trehalose injection did not have any adverse effects on the bunch quality. To develop a more effective method, further research is needed to elucidate the molecular mechanisms underlying the effect of trehalose on grape flower development.
