Effect Of Cultivation Measures On Growth And Secondary Metabolites Content Of Bletilla Striata

Appropriate artificial cultivation management measures can improve the yield of Bletilla striata and improve the quality of Bletilla striata.Field experiments were conducted to study the effects of different shading degrees,planting densities,and fertilizer levels on the growth,photosynthetic characteristics,and secondary metabolites levels of Bletilla striata.The results showed that:shading had a greater effect on growth characteristics than fertilization treatment and planting density,with the degree of shade deepening,seedling height and leaf area increased.Under light shading treatment,the root number,crown fresh weight,tuber dry fresh weight,and underground root fresh weight reached the maximum,and dry matter accumulated most.Therefore,severe shading should be used in the early stage and mild shading in the latter stage to optimize the growth status;The degree of shading and fertilizer application had a significant effect on the total amount of chlorophyll.Increasing shading could increase the total amount of chlorophyll and reduce chlorophyll a/b.Shading affected the diurnal variation of photosynthetic and white light.Moderate shading could increase the net photosynthetic rate,stomatal conductance and transpiration rate of Bletilla striata,and at the same time reduce the intracellular carbon dioxide concentration;Shading is the main affecting factor affecting the two secondary metabolic components,and the secondary metabolite content can be increased by prolonging the harvest period.The optimum cultivation condition is shading:60%;fertilization level:40(kg/666.7m2)Plant density:3.1(10,000 plants/666.7 m~2).