The establishment of apple orchards as temperate forest garden systems and their impact on indigenous bacterial and fungal population abundance in Southern Ontario, Canada

Abstract

This thesis investigated soil microbial abundances affected by different ground management systems in establishing apple (Malus domestica cv. Idared, M9) orchards in Ontario. Four treatments including forest garden systems with and without compost (FGSC and FGS) and grass understory systems with and without compost (GC and G) were established, sampled and analyzed over the establishing two years for gene copy abundance of soil arbuscular mycorrhizal (AM) fungi, total fungi, and total bacteria using quantitative real-time polymerase chain reactions. From Spring2013 to Fall2014 soil bacterial abundance decreased by -0.78, -0.84, -0.86, and -0.88 ±0.08 Log 16S gene copies g-1 dry soil, total soil fungal abundance increased by 2.12, 1.86, 1.82, and 1.78 ±0.15 Log ITS gene sequence copies g-1 dry soil, and AM fungal abundance decreased by -1.73, -2.15, -2.23, -2.04 ±0.55 Log AML gene sequence copies g-1 dry soil within respective treatments FGSC, FGS, GC, and G.