Epsilon Archive for Student Projects

Abstract

Alternaria solani is a worldwide present fungus that can cause a lot of damage
such as early blight in potato crops. Potato can suffer a lot of yield losses because
of this pathogen, and the main method used today to fight against it, is the
application of fungicides. Yet fungicides are chemicals that contaminate the
environment and are not assimilated so they can be found in water for example,
which can cause problems for human health as well. As the climate is becoming
warmer and warmer, it is also expected that the A. solani severity will increase,
which will induce more use of fungicides. A. solani resistance to fungicides has
been reported and seems to develop quickly. Firstly, it is important to study A.
solani resistance development to new fungicides as it may improve the possibility
for early detection of fungicide resistance. In this study, we looked at the mycelial
growth of A. solani field isolates by increasing the concentration of fluopyram, a
fungicide, in two growth assays (liquid and solid). Secondly, to be able to predict
the occurrence of early blight it is also important to investigate the survival and
growth of A. solani in the soil. Here we did a soil assay where we incubated A.
solani infected rye kernels in different soils under differents conditions (unsterilized
wet, unsterilized dry or sterilized) followed by a qPCR performed on the rye kernels
to assess the A. solani quantity. In our experiment, the growth of A.
solani decreased with the increase of fluopyram concentration. Moreover, the
growth reduction with decreased fluopyram concentration was reduced for the later
collection year, which indicates that the sensitivity to flupyram decreased over the
years. The growth of A. solani in the soil was affected by the said soil condition
(dry, sterilized or unsterilized). Our results are pointing to A. solani surviving better
in dry soils which is concerning knowing the expected temperature rise, as well as
the drought experienced today but also in the future.