Microbial strains from compost originated from circulated side streams : impact on root growth and root hairs

Sammanfattning: Spent mushroom compost, apple waste and other organic waste materials are of great potential to improve soil health, water holding capacity and to supress plant pathogens. Today compost is used in apple orchards as an additional fertilizer or soil amendment. The aim of the work is to examine the effect of bacterial strains isolated from compost blends containing different fractions of SMC, apple material and woodchips on root growth and root hair formation. Microorganisms play a vital role for growth stimulating effects, formation of root hairs and overall soil health with water uptake and nutrient availability in the soil. Three treatments with different fractions were included in the experiment with microbial enumeration on selective media for the targeted microorganisms. Isolated bacterial strains originated from compost were used in germination, evaluation of root growth and for the formation of root hairs. The results give a preliminary understanding of the microbial content of the compost in the different fractions and their potential to promote root growth and root hair formation.