Studies on the growth hormone of plants VII. The fate of growth substance in the plant and the nature of the growth process

摘要

Since the early work of Went (1928), it has been known that the growth substance of the Avena coleoptile may be obtained in the usual way, i.e. by diffusion into agar blocks, only from that part of the plant which produces it, namely the tip. The hormone is not recoverable in this way from those parts of the plant, such as the lower zones, which only make use of it. Recent work (Thimann, 1934) has, however, shown that by extraction with chloroform some growth substance is recoverable from the lower zones of the coleoptile. The results of this extraction method confirmed the earlier view that there is a marked concentration gradient of growth substance from tip to base.