Differences in growth-inhibitory activity among different parts of asparagus and the effects of activated carbon on its reduction
Asparagus (Asparagus officinalis L.) is a popular vegetable eaten in many different areas of the world. Plants include edible parts and other parts that cannot be used. In the production process, many non-usable parts, including cladophylls and storage roots, are put back into the soil or disposed of. It is necessary to address the issue of large amounts of non-usable parts that are generated in the production process. However, there are few reports on the active utilization of the cladophylls and storage roots as sources of useful constituent resources, and few studies have been conducted to examine the detailed distributions of useful constituent resources and substances related to growth-inhibitory activity, as well as the influences of their cultivation and environmental conditions. If the storage roots of asparagus are left in the soil following replanting, inhibitory substances will seep out and cause problems with replanting. This study aimed to examine the possibility of utilizing the non-usable parts of asparagus as useful constituent resources by focusing on growth-inhibitory activity in different parts of asparagus and the effects of flowable agent in activated carbon to reduce its growth-inhibitory effect using lettuce seedlings. Here we showed that different parts of asparagus comprise differences in the growth-inhibitory effect on lettuce seedlings. The growth-inhibitory effect was strong in the bulbils, belowground stems, and absorptive and storage roots, and weak in the cladophylls and lateral branches. When activated carbon was added to the agar medium, the inhibitory activity of residues of asparagus plants on the growth of lettuce seedlings was markedly reduced. A direct transfer of the results to conditions of replanted asparagus fields cannot be made. However, it seems likely that the addition of active carbon may also reduce the growth inhibition by asparagus plant parts during replanting of asparagus under field conditions.
Tang, T.L. and Motoki, S. (2018). Differences in growth-inhibitory activity among different parts of asparagus and the effects of activated carbon on its reduction. Acta Hortic. 1223, 257-262
Asparagus officinalis L., flowable agent in activated carbon, non-usable parts, the rhizosphere soil bioassay method