Inhalt:
The use of beneficial fungi has become a reliable alternative to reduce the application of pesticides in agriculture. Several studies have noted the beneficial effects of the arbuscular mycorrhizal (AM) fungi and Trichoderma spp. to improve plant productivity and soil quality. Synergistic effects of both fungi on plant growth as well as on the control of various plant diseases have been previously shown. However, mycoparasitism by Trichoderma spp., a major mechanism to control fungal pathogens, has also been reported on AM fungi. Thus, for an optimal management of microbial consortia, it is necessary to thoroughly understand the interaction between these two fungi to guarantee these successful applications under field condition. The objective of this thesis is to study the impact of T. harzianum on an AM fungi, Glomus sp. in order to develop a microbial inoculum containing both beneficial fungi. Here we devised in vitro systems to monitor the development of both fungi, via non-destructive microscopic observations. The effect of T. harzianum on the AM symbiosis was investigated and the applicability of these beneficial fungi co-entrapped in alginate beads evaluated. We observed that T. harzianum affected the viability of Glomus sp. and its capacity to transport P when the saprotrophic fungus was inoculated on AM established networks. The saprotroph was able to colonize the root system via a privilege entrance through the hyphae. Interestingly, when T. harzianum and Glomus sp. were inoculated at the same time, via co-entrapment in alginate beads, this mycoparasitism was infrequently observed, while a stimulation of spore production was noted. This supported the potential of the co-entrapment of both fungi for agro-environmental application. Further questions needs to be addressed regarding the role of AM fungi as a pathway for the entrance of T. harzianum into the roots of potato and the ecological significance of co-entrapment of both fungi under field condition. ; (AGRO 3) -- UCL, 2011
Anmerkung:
Dissertation 2011
Sprache:
Englisch
