Epsilon Archive for Student Projects

Abstract

Modern agriculture and horticulture rely on pesticide and mineral fertilizer use that causes pollution
and harm to the environment. With changing pesticide legislation, there is pressure to develop more
resilient and environmentally sustainable systems. One of the potential ways to limit mineral
fertilizer use while creating more stable growing systems is to implement circular nutrient economy
in the form of using rest-product compost. As in many other cultures, implementing conventional
methods for apple orchards tend to cause soil degradation.
This study investigates the potential of using locally produced rest-product compost as fertilizer
and the implications on soil health, growth of apple and the apple rhizosphere microbial community.
During nine weeks, apple branches (Malus domestica) of root stock Alnarp 2 were grown in pots in
a polytunnel. Treatments consisted of a treatment to mirror conventional practices, grown in apple
orchard soil and rest-product compost amended orchard soil in a 20:80 ratio to match commercial
basal fertilization. The apple orchard soil treatment was fertilized with mineral fertilizer. Growth
measurements such as longest leaf, number of leaves and accumulated shoot growth were examined
as well as soil physical properties before and after cultivation. The microbiome was monitored
during cultivation via the microfluidic soilchip and examined under microscope. Abundance of
different microbial groups were investigated.
Statistical analyses, including standard least-square and t- tests, were employed to evaluate
growth patterns, microbial abundance and soil physical properties. Growth was improved by the
amendment of rest-product comport. Significant differences were observed in shoot length and
number of leaves. Significant differences were found between the treatments in microbial groups
such as hyphae, amoeba, lobose amoeba, ciliophora, and flagellates. These findings suggest that
employing good rest-product compost practices can enhance soil and growth, contributing to more
environmentally sustainable apple cultivation practices by reducing mineral fertilizer use.