Long-term ecological effect of climate change on locust dynamics

This study shows that there are significantly negative correlations between locust population abundance and temperature during last one millennium, contradicting traditional observation. This finding indicated that biological disaster may have link with large-scale climate change in China and we should pay more attention that low- and high-frequency climate factors may have opposite effect on population dynamics. ——PNAS (105:16188-16193)
By reconstructed a 1,910-y-long time series of outbreaks of Oriental migratory locusts (Locusta migratoria manilensis) in China, the locust–precipitation correlation was found to hold at least as far back as to A.D. 500, the locust–temperature correlation was weaker and less consistent.——PNAS(108(10):3882-3887)

Ecological and physiological mechanism of insect in response to elevated CO2

Increases of atmospheric CO2 concentration is considered to have substantial effects on ecosystems through modifying the multi-trophic species interactions. We determined the nutrition and resistant relationship between leguminous plant and aphid under elevated CO2 (750ppm vs. 400ppm). We showed that Medicago truncatula enhanced biological nitrogen fixation to compensate for dilution effect on the nitrogen under elevated CO2. The pea aphid can further promote amino acid metabolism both in its host plant Medicago truncatula and its endosymbiotic Buchnera to increase the feeding efficiency under elevated CO2——Global Change Biology 19: 3210-3223

Furthermore, elevated CO2 increased non-glandular and glandular trichome density of plant leaves,and enhanced the ineffective salicylic acid-dependent defense pathway but decreased the effective jasmonic acid and ethylene-dependent defense pathway in aphid-infested plants, which decreased the plant resistance to aphids . These effects in turn drive the change of feeding behavior of aphids.——Plant Science 210: 128-140 New Phytologist 201 (1): 279-291

During the initial stages of feeding, aphids showed a delayed first probing time, increased the probing frequency, and spent more time to investigate the leaf surface under elevated CO2. During the feeding ingestion stage, however, elevated CO2 increased the phloem sap feeding time. Thus, these results suggested that, elevated CO2 facilitated the passive feeding of aphids by decreasing the resistance and enhancing the N nutrition of host plant.——Plant Cell & Environment. DOI: 10.1111/pce.12306