The Effects of Biological Agents on Survival, Biomass and Foliar Nutrient Concentrations of Mongolian Pine (Pinus sylvestris var. mongolica) Seedlings Planted on Keerqin Sandy Lands, China

The experiments were conducted by planting in the field of 2 year-old Mongolian Pine (Pinus sylvstris var. mongolica) seedlings processed with Pt mycorrhizal agents, ABT rooting powder, HRC water-absorbing agent and GRR plant development and growth regulator. The results were as follows: (1) Pt3 and ABT had significantly increased survival rates of seedlings, which were 29.3%, 23.6% and 9.4% higher than that of controlled seedlings, respectively.; (2) Pt3 and ABT had enhanced the growth of the fine root(<2mm), which were 34.72 and 15.18 cm longer than that of controlled seedlings; the regression analysis had showed that fine roots quantity was positively related to seedling survival rate; (3) The growth indexes of the average individuals with Pt3, ABT and HRC were higher than those of untreated seedlings; (4) Pt3 and ABT also effectively promoted the absorption of main nutrients such as N, P, and K in the needle of seedling.