Effects of Shade Treatments on Vine Growth and Production of Tubers and Propagules of Japanese Yam (Dioscorea Japonica) in Tea Gardens

Author(s)

INAGAKI, Hidehiro , ISHIWATA, Kasumi ,

Download Full PDF Pages: 12-22 | Views: 197 | Downloads: 67 | DOI: 10.5281/zenodo.7421535

Volume 6 - October 2022 (10)

Abstract

Tea gardens have specific light and shade conditions because the tea trees are densely planted, with only a narrow space between rows. Therefore, in practice, the variety of weeds that grow in tea gardens is limited. Japanese yam (Dioscorea japonica) is a serious weed that grows under shade conditions in tea gardens. This study investigated the effects of shade conditions on the growth of Japanese yam vines and the production of tubers and propagules. We observed that shading did not limit the growth of Japanese yam vines that emerged from the tubers, and even under strong shading conditions of 0% relative irradiance, vines of Japanese yam were able to growth more than 2 m. Furthermore, although the formation of new tubers and production of propagules were limited under strong shading conditions, they were not limited under 50% relative irradiance. Since the relative irradiance at 10 cm below the canopy after harvesting in this study was 65 %, there is concern that Japanese yam produces propagules even under the canopy of tea plants. On the other hand, the plants from tubers emerged and reached the canopy of tea trees earlier than those from propagules. This suggests that differences in emergence time and growth speed of vines between plants from tubers and propagules may be a factor in prolonging the duration of weeding Japanese yams.

Keywords

Japanese yam (Dioscorea japonica), vine weed, tea garden, propagule

References

           i.          Asano H. 2001. Effect of Shading on Weed Emergence in Paddy Fields. Journal of Weed Science and Technology, 46:31–36.

         ii.          Cai Z. Q. 2011. Shade delayed flowering and decreased photosynthesis, growth and yield of Sacha Inchi (Plukenetia volubilis) plants, Industrial Crops and Products, 34: 1235–1237.

       iii.          Cavagnaro J. B. and Trione S. O. 2007. Physiological, morphological and biochemical responses to shade of Trichloris crinita, a forage grass from the arid zone of Argentina, Journal of Arid Environments, 68: 337–347.

       iv.          Colbach N., Gardarinb A. and Moreaua D. 2019. The response of weed and crop species to shading: Which parameters explain weed impacts on crop production?, Forest Ecology and Management, 212: 302–314.

         v.          Dai Y.J., Shen Z. G., Liu Y., Wang L. L., Hannaway D. and Lu H. F. 2009. Effects of shade treatments on the photosynthetic capacity, chlorophyll fluorescence, and chlorophyll content of Tetrastigma hemsleyanum Diels et Gilg, Environmental and Experimental Botany, 65: 177–182.

       vi.          Deng Y. M., Li C. C, Shao Q. S., Ye X. Q. and She J. M. 2012. Differential responses of double petal and multi petal jasmine to shading: I. Photosynthetic characteristics and chloroplast ultrastructure, Plant Physiology and Biochemistry, 55: 93–102.

     vii.          Hori Y. 1984. Life history and population demography of Dioscorea japonica. In: Kawano, S. (ed), Life history and evolution of plants. aphBaifukan, Tokyo: p. 157–172．

   viii.          Ichihara M., Togawa M. and Haga H. 2020. Vegetation in tea field margins and climbing plants on tea bush canopies in Shizuoka Prefecture, Japan. Journal of Weed Science and Technology, 65: 114–117.

       ix.          Ichihara M., Uchiyama M., Murakami G., Yamashita M. and Sawada H. 2022. Weed vegetation in organic and conventional tea gardens in Shizuoka Prefecture. Journal of Weed Science and Technology, 67: 25–30.

         x.          Iida T. 2001. Japanese yam. Rural Culture Association Japan, Tokyo: p. 12–18．

       xi.          Inagaki H. and Ishiwata K. 2022. Occurrence of Japanese yam (Dioscorea japonica) as vine weed in tea gardens, International Journal of Agriculture and Biological Sciences (in print).

     xii.          Ito M., Iyama Y. and Ueki K. 1987. Changes in the floristic composition of orchard ground cover in relation to light conditions. Journal of Weed Science and Technology, 32: 292–299

   xiii.          Knake E. L. 1972. Effect of Shade on Giant Foxtail. Weed Science, 20, 588–592.

    xiv.          Murphy T.R. and Gossett B. J. 1981. Influence of Shading by Soybeans (Glycine max) on Weed Suppression. Weed Science, 29: 610–615.

      xv.          Noguchi K. and Nakayama K. 1978. Studies on competition between upland crops and weeds III. Effect of shade on growth of weeds, Japanese Journal of Crop Science, 47: 56–62.

    xvi.          Seo S.W. 2012. Weed control in tea gardens in Mie prefecture, Japan. Journal of Weed Science and Technology, 57: 67–68.

  xvii.          Seo S.W. 2016. Weed control in and around tea gardens in central and western Shizuoka Prefecture, Japan. Journal of Weed Science and Technology, 61: 157–158.

xviii.          Terasawa T., Asano H. and Hirose S. 1981. Ecological studies on environmental adaptation in weeds 4. The effect of shading on growth and seed productive structure of large crabgrass and common purslane. Journal of Weed Science and Technology, 26:19–23.

    xix.          Williams E. D. 1970. Effects of decreasing the light intensity of the growth of Agropyron repens (L.) Beauv. in the field. Weed Research, 10: 360–366.

INAGAKI, Hidehiro, Effects of Shade Treatments on Vine Growth and Production of Tubers and Propagules of Japanese Yam (Dioscorea Japonica) in Tea Gardens, International Journal of Agriculture and Biological Sciences 10(2022):12-22 DOI: 10.5281/zenodo.7421535