Impact of heteroptera pentatomidae feeding and oviposition on photosynthesis of herbaceous plants and egg parasitoids host location

The present study was designed to examine the effect of heteroptera pentatomidae feeding and/or oviposition on photosynthesis. Murgantia histrionica and Nezara viridula were fed on Brassica and Phaseolus plants, respectively. The changes in photosynthetic gas exchange and chlorophyll fluorescence parameters were followed immediately after the feeding as well as during the post-feeding period (24, 48 and 72 h). Murgantia feeding caused visible damage on leaf lamina, whereas this was not the case with Nezara feeding. In both cases a substantial decrease (50%) in photosynthesis was observed, which was partially restored only in Phaseolus plants by the end of the experiment. By using high resolution digital chlorophyll fluorescence imaging, no effect of Murgantia feeding or oviposition on the maximal quantum yield of PSII photochemistry (Fv/Fm), and on the PSII efficiency in illuminated leaves was observed, in leaf areas that in which the insects did not feed. However, in the leaf areas with visible insect feeding damage fluorescence parameters were negatively affected. Nezara feeding caused a reduction of all fluorescence parameters indicating that, despite the absence of visible damage, the photochemical properties of the leaves were permanently impaired.