Impact of phylloplane management on microbial populations

Abstract

The impact of apple orchard management on leaf microbial populations was investigated during the 2001/2002 growing season Apple leaves were collected in spring and autumn from two certified organic (BioGro) and IFP (Integrated Fruit Production) managed apple orchards at each of three New Zealand sites (Hawkes Bay Nelson and Canterbury) Phylloplane epiphytes were recovered by leaf washing using a stomacher blender and the microorganisms enumerated using serial plate dilutions The microorganisms were separated into recognisable taxonomic units (RTUs) based on colony morphology Analysis of both spring and autumn samples showed that leaves from all three sites from organic orchards harboured significantly more colony forming units than were found on leaves from IFP orchards Overall population richness (based on RTUs/ leaf sample) was also significantly higher in organic than IFP orchards