For this study, Smilex powder, a pesticide, was sprayed on the Altari radish, and then underground water, Chitosan solution (×500), and wood vinegar solution (×1000) were evenly sprayed on the Altari radish respectively. Samples of Altari radishs for residual pesticide analysis were taken two hours, 1 day, 7 days, and 15 days after treatments, and the detectable concentration and degradability of procymidone, the pesticide residue, were measured. The results obtained are as follows: 1. When detectable concentration of procymidone within the altari radish was measured, treatment plots sprayed with underground water, Chitosan solution (×500), and wood vinegar solution (×1000) were found to show lower detectable concentration than the non-treatment plot which was sprayed with pesticide only. Especially, the treatment plots sprayed with Chitosan solution (×500), and with wood vinegar solution (×1,000) showed lower values than the average. 2. When the degradability of procymidone within the Altari radish was measured, the plot treated with Chitosan solution (×500) and the plot treated with wood vinegar solution (×1,000) were found to have relatively higher degradability of procymidone. There were not much differences among testing materials in the degradability of residual pesticides. However, the plot treated with Chitosan solution (×500) showed higher degradability. In terms of average degradability with time, degradability increased sharply 7 days after the foliar application of testing materials. 3. When the daily far-sighted view survey was conducted in order to find out growth disorder and damage on the Altari radish plants by the treatment of underground water, Chitosan solution (×500), and wood vinegar solution (×1,000), no symptomatic physiological disorders was observed on all the plants tested during the whole growing season at the tested concentration level.

A research was conducted to investigate the effect of treatment of woody charred materials such as wood vinegar, charcoal, and mixture of wood vinegar and charcoal on the growth and components of tomato and chinese cabbage. The effect of treatment of woody charred materials on the growth and components of tomato the research findings are as follows. The total number of soil microorganisms increased in the groups treated with woody charred materials compared with the control. The fruit number, fruit length, fruit diameter, fruit weight, hardness and sugar contents of tomato did not show significant difference in all plots treated with woody charred materials, but the plot treated with wood vinegar + charcoal showed relatively higher values in general. Vitamin C contents were shown higher in the plots treated with woody charred materials than the control, and among the treatment plots. The effect of treatment of woody charred materials on the growth and components of chinese cabbage the research findings are as follows. The soil chemical components did not change before and after the treaiment of woody charred materials. The total number of soil microorganisms increased in the treatment plots compared with the control, The leaf length, leaf width, inner leaf number, plant weight, and head weight of Chinese cabbage treated with woody charred materials were in general larger than the comtrol. Among the treatment plots, the plot treated with wood vinegar + charcoal showed slightly higher values. The contents of minerals in chinese cabbage such as Ca, Fe, K, Mg and Mn were higher in the treatment plots than the control.

From the experiments on the effect of chitosan and wood vinegar, which are environment-friendly materials, on the growth of eggplant and leaf lettuce, the following results were obtained. 1. The effect of chitosan and wood vinegar treatment on the growth of eggplant 1) There was no difference in soil component elements before and after treatment with chitosan and wood vinegar. The total number of microorganisms tended to increase after treatment with chitosan and wood vinegar, while the number of bacteria increased among microorganisms. However, there was no consistent tendency in the number of Acinomycetes, fungi, and trichodema between treatments. 2) The growth and the yield of eggplant increased compared with the control plot in both the chitosan-treated plot and the wood vinegar-treated plot. However, there was no significant difference between the treatments. The yield of eggplant per 10a increased in chitosan- and wood vinegar-treated plots compared with the controlled plot. There was no significant difference in treatments, however, the plot treated with 800 times-diluted solution showed a higher growth. 2. The effect of chitosan and wood vinegar treatment on the growth of leaf lettuce 1) There was no difference in soil component elements before and after treatment with chitosan and wood vinegar. The number of bacteria increased among microorganisms. However, there was no consistent tendency in the number of Acinomycetes, fungi, and trichodema between treatments. 2) The growth of leaf lettuce in both chitosan-treated plot and wood vinegartreated plot increased compared with the control plot, however, there was no significant difference between the treatments. On the whole, the plot treated with greater concentration showed a higher growth.