Article | 4. 2014 Vol. 32, Issue. 2
Development of Root Media Containing Carbonized and Expanded Rice Hull for Container Cultivation of Horticultural Crops



Department of Horticultural Science, Chungnam National University1




2014.4. 157:164


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Objective of this research was to develop root media containing expanded rice hull (ERH) and carbonized rice hull (CRH). To achieve this, the physico・chemical properties of two materials were analysed and blended with peatmoss (PM) or coir dust (CD) with various ratio. Based on the physical properties of the blended materials, 4 root media were selected for future experiment. After the analysis of pH and EC of the selected root media, the kinds and amount of pre-planting nutrient charge fertilizers (PNCF) incorporated into each root medium were varied, and then, final chemical properties of the root media were analysed. The total porosity (TP), container capacity (CC), and air-filled porosity (AFP) were 81.3%. 39.9%, and 41.4% in ERH and 77.6%, 64.1%, and 13.5% in CRH, respectively. The percentage of easily available water (EAW, from CC to 4.90 kPa tension) and buffering water (BW, 4.91-9.81 kPa tension) were 11.37% and 5.27%, in ERH and 17.26% and 14.28% in CRH, respectively. The pH of ERH was 7.1, but it was extremely high in CRH such as 11.2. The EC and CEC were 1.31 dS・m-1 and 12.1 meq・100 g-1 in ERH and 6.53 dS・m-1 and CEC 7.79 meq・100 g-1 in CRH, respectively. The ranges of TP, CC and AFP in 4 selected media (PM + ERH, 6:4, v/v; CD + ERH, 8:2; PM + CRH, 7:3; CD+CRH 6:4) were 89.2-90.3%, 67.3-81.8%, and 8.3-21.9%, respectively. The pHs and ECs in root media containing peatmoss such as PM + ERH (6:4) and PM + CRH (7:3) were 4.0-4.3 and 0.33-0.365 dS・m-1, whereas those of CD + CRH were 7.4-7.9 and 1.282 dS・m-1. The pHs and ECs, however, analysed before and after the incorporation of PNCF in each root medium were not significant different. This result indicated that the incorporated fertilizers in PNCF to adjust medium pH did not dissolve enough to influence medium pH, but it is very normal in root media containing dolomitic lime and sulfur powder in adjusting pH. The Information obtained in this study may facilitate an effective formulation of root media containing rice hulls.



1. Argo, W.R. 1998a. Root medium physical properties. HortTechnology 8:481-485.  

2. Argo, W.R. 1998b. Root medium chemical properties. HortTechnology 8:486-494.  

3. Bunt, A.C. 1988. Media and mixes for container grown plants. Unwin Hyman, London.  

4. Cataldo, D.A., M. Haren, L.E. Schrader, and V.L. Young. 1975. Rapid colorimetric determination of nitrate in plant tissue by nitration of salicylic acid. Commun. Soil. Sci. Plant Anal. 6:71-80.  

5. Chaney, A.L. and E.P. Marback. 1962. Modified reagents for determination of urea and ammonia. Clinical Chem. 8:130-132.  

6. Chapman, H.D. and P.F. Pratt. 1961. Method of analysis for soil, plants and waters. Univ. of Calif., Div. Agr. Sci., Berkeley, CA.  

7. Choi, J.M., J.W. Ahn, J.H. Ku, and Y.B. Lee. 1997. Effect of medium composition on physical properties of soil and seeding growth of red pepper in plug system. J. Kor. Soc. Hort. Sci. 38:618-624.  

8. Choi, J.M., J.H. Chung, and J.S. Choi. 1999a. Physical properties of pine bark affected by peeling method and improving moisture retention capacity. J. Kor. Soc. Hort. Sci. 40:363-367.  

9. Choi, J.M., H.J. Chung, and J.S. Choi. 2000. Physico・chemical properties of organic and inorganic materials used as container media. Kor. J. Hort. Sci. Technol. 18: 529-535.  

10. Choi, J.M., H.J. Chung, B.G. Seo, and C.Y. Song. 1999b. Improved physical properties in rice-hull, saw dust and wood chip by milling and blending of recycled rockwool. J. Kor. Soc. Hort. Sci. 40:755-760.  

11. Choi, J.M., I.Y. Kim, and B.K. Kim. 2009. Root substrates. Hackyesa, Daejeon, Korea.  

12. Choi, J.M., C.Y. Shim, and J.S. Choi. 2002. Effect of phosphorus fertilization on changes in concentrations of nutrients in rice- hull based root media, crop growth, and nutrient contents of chrysanthemum. J. Kor. Soc. Hort. Sci. 43:235-238.  

13. Choi, J.M., C.Y. Shim, and H.J. Chung. 2001. Effect of liming fertilization on changes in concentrations of nutrients in rice- hull based root media, crop growth, and nutrient uptake of chrysanthemum. J. Kor. Soc. Hort. Sci. 42:553-556.  

14. Hendershot, W.H., H. Lalande, and M. Duqutte. 1993. Ion exchange and exchangeable cations, p. 167-176. In: M.R. Carter (ed.). Soil sampling and methods of analysis. Can. Soc. Soil Sci., Lewis Publisher, Toronto.  

15. Lee, P.O., J.S. Lee and J.M. Choi. 2001. Effect of liming fertilization on changes in medium pH, nutrient concentrations, and seed germination of ‘Potomac Red’ snapdragon in plug production. J. Kor. Soc. Hort. Sci. 42:596-600.  

16. Maher, M., M. Prasad, and M. Raviv. 2008. Organic soilless media components, p. 459-504. In: M. Raviv and J.H. Leith (eds.). Soilless culture: Theory and practice. Elsvier, London.  

17. Milks, R.R., W.C. Fonteno, and R.A. Larson. 1989. Hydrology of horticultural substrates: II. Predicting physical properties of media in containers. J. Amer. Soc. Hort. Sci. 114:53-56.  

18. Nelson, P.V. 2003. Greenhouse operation and management. 6th ed. Prentice Hall, Englewood Cliffs, NJ.  

19. Song, C.Y., J.M. Park, J.M. Choi, C.S. Bang, and J.S. Lee. 1996. Effect of composted rice-hull on physic-chemical properties of growing media and growth of Petunia hybrid. J. Kor. Soc. Hort. Sci. 37:451-454.   

20. Technical Association of Pulp and Paper Industry (TAPPI). 1975. Tappi standards and suggested methods. TAPPI, Georgia, USA.  

21. Wallach, R., F.F. da Silva, and Y. Chen. 1992. Hydraulic charac-teristics of Tuff (Scoria) used as a container medium. J. Amer. Soc. Hort. Sci. 117:415-421.  

22. Warncke, D.D. 1986. Analysing greenhouse growth media by the saturation extraction method. HortScience 211:223-225.