Chrysanthemums (Dendranthema grandiflorum ‘Iwanohakusen’) were grown in a greenhouse with complete nutrient solution system to investigate the effect of silicon (Si) supplement on salt induced deleterious effects in chrysanthemum plants. The experiment was conducted in plastic pots supplemented with a mixture of upland soil : leaf mold : river sand (3:3:4, v:v:v). Si and salinity were treated in combination with two levels of NaCl (0 and 100 mM) and two sources of silicon (K2SiO3, KSi and silicate fertilizer, SiF) at the same concentration (1.8 mM Si) by weekly-drenching for 12 weeks. Chrysanthemum plants supplemented with Si increased in fresh and dry matter enhancing water content and salinity tolerance. The plants grown under salt stress produced less fresh and dry matter than control plant. However, Si supplement to plants under salt stress ameliorated negative effects of salt stress. In soil, EC and NaCl increased by salt stress were mitigated by Si supplement. Salt stress significantly decreased the contents of K and P in leaf, but Si supplement under salt stress significantly recovered the decreased contents with enormous desorption of K and P in soil. Added Si significantly increased content of available SiO2 with its adsorption by salt stress in soil, which was directly related to Si accumulation in leaf. However, Si uptake by roots was suppressed by salt stress irrespective of Si supplement. Si supplement did not ameliorated the negative effects of salt stress on chlorophyll content and membrane integrity in leaf of chrysanthemum plant although significantly increased Si content in leaf, but reversed pest (Liriomyza trifolii) resistance to above-control level.

Introduction
 Materials and Methods
  Plant culture and treatments
  Sampling and determination of water content,and salinity tolerance from biomass
  Determination of chlorophyll content andelectrolyte leakage, and assessment of leafdamage by leafminer larvae
  Determination of chemical properties andmacronutrient and Si contents in soil
  Determination of macronutrient and siliconcontents in plant tissues
  Statistical analysis
 Results
  Effects of Si on biomass and salinity toleranceof chrysanthemum under salt stress
  Effects of silicon on macronutrients contentsin pot-soil and plant leaf under salt stress
  Effect of Si on av. SiO2 content of soil and Siuptake and accumulation of chrysanthemumplants under salt stress
  Effect of Si on the chlorophyll and Ca contents,membrane integrity and pest (leafminer larvae)resistance under salt stress
 Discussion
 Conclusion
 References

• Young Shin Chon(Dept. of Horticultural Science, Gyeongnam National University of Science and Technology, Jinju 52725, Republic)
• Su Hyeon Ha(Dept. of Horticultural Science, Gyeongnam National University of Science and Technology, Jinju 52725, Republic)
• Kyeong Jin Jeong(Dept. of Horticultural Science, Gyeongnam National University of Science and Technology, Jinju 52725, Republic)
• Jae Gill Yun(Dept. of Horticultural Science, Gyeongnam National University of Science and Technology, Jinju 52725, Republic) Corresponding author