The effect of global change on multitrophic interactions of sugar beet

Global climate change is one of the major serious threats to biodiversity and ecosystem functioning. Species and populations are being challenged by multiple stressors (biotic and abiotic), making it more difficult for them to adapt in climate regimes. Different species in food webs may respond differently to climate change and trickle through trophic interactions. Soil salinity and drought poses a serious risk to the food security and ecological interactions and species changing various aspects of their life cycles, such as seasonal growth and phenology patterns. Molecular control mechanisms for stress tolerance are based on the activation and regulation of specific stress-related genes which involved in signaling, transcriptional control, protection of membranes and proteins, and free-radical and toxic-compound scavenging. Single biotic or abiotic stresses may change the pattern of emission of secondary metabolites like plant volatile organic compounds (VOCs), stress hormones and altering formation of new compounds as well as change their physiology. VOCs act as warning signals in plant communities, plant herbivore interactions, attraction of parasitoid at multiple trophic levels. VOCs emission in various biotic and abiotic stresses the combination of two or more stresses may produce unpredictable patterns and levels of emission. Indirect defenses are mostly associated with defense against herbivores and protect the plant through manipulation of the behavior of predators or parasitoids of an attacking herbivore. Thus, indirect defenses employ a third trophic level by attracting natural enemies of the plant’s attacker. Both direct and indirect defenses can be constitutive or induced. In my project, I will investigate, how abiotic (soil salinity & drought) and biotic stresses (Aphis fabae L2 and Pegomya betae) changes the morphology and physiology (chlorophyll fluorescence Fv/Fm, ETR, ФPS II) of the sugar beet plants and how these abiotic factors influences the insects’ and their associated parasitoids’ life. Indirect defense mechanism (crosstalk with plant and parasitoids) also considered by investigating the behavior of the parasitoids through six arm olfactometer, quantification of VOCs by GC-MS and the analysis of primary metabolites by GC-MS. By considering all the above data, finally we may suggest an effective biocontrol way to manage insects.

Involved colleague(s): Rahman, Rostás