Effects of Lignin on Root Activity and Soil Nutrients of Malus hupehensis. var. pingyiensis under the Use of Organic Fertilizer

One-year Malus hupehensis. var. pingyiensis seedlings potted in soil mixed with 10% or 40% organic fertilizer were treated with two concentrations of lignin (1.5 and 2.5 g·kg-1), and detected the effects of lignin on root activity and soil nutrients in rhizosphere soil of Malus hupehensis. var. pingyiensis. (1) Lignin improved root activity of Malus hupehensis. var. pingyiensis, increased soil available nitrogen contents and soil organic matter contents. (2) Under 10% organic fertilizer, lignin improved soil available P and K contents. The root activity in Malus hupehensis. var. pingyiensis was the largest in 2.5 g·kg-1 lignin treatment. (3) Under 40% organic fertilizer, compared with the CK2 (the treatment of soil with organic fertilizer content 40%), lignin decreased the content of rhizosphere soil available K. 1.5 g·kg-1 lignin treatment had obviously increased the content of soil available P. The root activity was the largest in 2.5 g·kg-1 lignin treatment, while the content of rhizosphere soil available K lowered 8.5% compared with that of CK2 in the same treatment. Lignin changed the soil nutrients, 2.5 g·kg-1 lignin significantly improved root activity of Malus hupehensis. var. pingyiensis. The results provided a theoretical basis for the regulation of root activity and soil nutrients in Malus hupehensis. var. pingyiensis.