Physical Requirements of Seedling Blocks Used in an Automatic Vegetable Transplanter

• Published in: Nogyo Shisetsu (Journal of the Society of Agricultural Structures, Japan) Vol. 19; no. 1; pp. 22 - 28
• Main Authors: SAITO, Takahiro, WANG, Jaw-Kai, AI, Fusakazu, AOYAMA, Tomoo, FUNADA, Shu, WATANABE, Kengo, TOJO, Seishu
• Format: Journal Article
• Language: English; Japanese
• Published: The Society of Agricultural Structures, Japan 1988
• ISSN: 0388-8517; 2186-0122
• DOI: 10.11449/sasj1971.19.22

Automatic vegetable transplanters can be used to decrease labor costs and increase uniformity of growth in row crops, however, they require soil seedling blocks which are highly adaptable for use in handled mechanically. This study has determined the basic requirements for soil blocks to be used in automatic transplanters. It is evaluated that the strength of soil blocks is greatly affected by the initial compaction level, the irrigation level and the root growth. By the time the soil blocks are transplanted to the fields, the physical properties of soil blocks are quite different from their initial condition. The amount of water added immediately before transplanting also has a great effect on strength of soil block. It is desirable to maintain the initial strength of the soil blocks between 2-5kgf/cm2 in unconfined compression tests. This strength of compaction is equivalent to that of the medium compaction blocks tested. It makes the roots of seedling plants grow rapidly. By enhancing the root growth until the time of transplanting, the strength and the adaptability of the soil blocks may be maximized. This research shows that the seedlings can now be modified to be suitable for automatic transplanters by controlling the physical properties and the environment in which they are produced.