A sand culture pot experiment by using a two-factor completely randomized design was conducted to investigate the growth patterns of Trisetum tibeticum seedlings under nitrogen， phosphorus， potassium deficiency， and water shortage conditions. The experiment included four nutrient treatments： complete nutrition （CN）， nitrogen deficiency （ND）， phosphorus deficiency （PD）， and potassium deficiency （KD）. And four water treatments： 80% field capacity （W₁）， 60% field capacity （W₂）， 40% field capacity （W₃）， and 20% field capacity （W₄）. The results showed that plants of ND treatment exhibited stunted growth with withered leaves， leaves of PD treatment appeared dark green， and leaves of KD treatment showed yellowing and curling at the tips. Water shortage reduced plant height， and growth rates of ND and PD treatments showed declining trends after three weeks. Nutrient-water interactions significantly influenced leaf length， leaf width， root length， root surface area， root volume， above-ground and below-ground biomass， and root-to-shoot ratio （P<0.05）. Under different water conditions， ND treatment consistently resulted in the shortest leaf length， while CN treatment exhibited the greatest leaf width. Water shortage promoted root development in CN treatment， with the largest root surface area and root volume observed at W₄. ND and PD treatments increased the root-to-shoot ratio， with biomass allocation shifting towards below ground parts， while KD had no significant effect on the root-to-shoot ratio. Therefore， the interaction between water shortage and nutrient deficiency synergistically inhibits the growth of Trisetum tibeticum. In seedling cultivation of Trisetum tibeticum， enhanced growth monitoring and timely targeted supplementation should be implemented.

Trisetum tibeticum  /  Nutrient deficiency  /  Water shortage  /  Seedling growth  /  Stress interaction