Effect Of Ectomycorrhizal Fungi On The Activities Of Enzymes In Soil

It was reported that ectomycorrhizal fungi increased surface area of root for nutrient and water absorption, promoted the abilities of nutrient and water uptake of plant, enhanced the availability of soil nutrients , which were all beneficial to the growth of plant and increased the biomass of plant.Soil enzymes are stable proteins that catalyze biochemical reactions and play important roles in circulation and conversion of materials in soil. The activities of soil enzymes are also of importance in decomposition and conversion of organic materials in soil, as well as enhancing the availability of soil nutrients and promoting the nutrients absorption by plants. Many researches have investigated factors influencing the activities of soil enzymes, but little had referred to the effect of ectomycorrhizal fungi on the activities of enzymes in soil.In this experiment three ectomycorrhizal fungi — Lactarius delicious (Ld), Suillus placidu (Sp 504)and Laccaria Lb bicolor (Lb 238N) — were inoculated in seedlings of Pintts Massoniana. The growth of the seedling (height, diameter and dry weight), contents of nutrients (N, P, K) and the activities of soil enzymes (phosphatase, invertase, dehydrogenases, urease and catalase) were studied after 9 months. The results were as follows:1. The height, diameter and dry weight of the seedlings of Pinus Massoniana that inoculated with Ld (Ld 01 and Ld 03), Sp 504 and Lb 238N were significantly increased comparing with CK(p=0.05). The height of seedlings inoculated with Ld 01 increased 45.91%, which was the highest in three treatments. The basal diameter and the dry weight of the seedlings inoculated with Lb 238N increased 39.73% and 103.11%, respectively. The root/shoot ratio showed a tendency of reduction, but it was not obvious.2.The contents of nutrients (N, P, K) in seedlings changed, to some extent, after inoculated with ectomycorrhizal fungi. The changes of N were not obvious, whilst contents of P varied among three ectomycorrhizal fungi, some increased and others diminished in roots and plants. Contents of K in seedlings inoculated with ectomycorrhizal fungi significantly increased in the plants , comparing with CK(P=0.05), but it was not obviously increased in the roots. The accumulation of N, P and K significantly increased (P=0.05) because of the obviously increase of the biomass.