Biogenic volatile organic compound emissions from leaves and fruits of apple and peach trees during fruit development

Biogenic volatile organic compounds(BVOCs)are widely involved in a variety of atmospheric chemical processes due to their high reactivity and species diversity.To date,however,research on BVOCs in agroecosystems,particularly fruit trees,remains scarce despite their large cultivation area and economic interest.BVOC emissions from different organs(leaf or fruit)of apple and peach trees were investigated throughout the stages of fruit development(FS,fruit swelling;FC,fruit coloration;FM,fruit maturity;and FP,fruit postharvest)using a proton-transfer-reaction mass spectrometer.Results indicated that methanol was the most abundant compound emitted by the leaf(apple tree leaf 492.5±47.9 ng/(g·hr),peach tree leaf 938.8±154.5 ng/(g·hr)),followed by acetic acid and green leaf volatiles.Beside the above three compounds,acetaldehyde had an important contribution to the emissions from the fruit.Overall,the total BVOCs(sum of eight compounds studied in this paper)emitted by both leaf and fruit gradually decreased along the fruit development,although the effect was significant only for the leaf.The leaf(2020.8±258.8 ng/(g·hr))was a stronger BVOC emitter than the fruit(146.0±45.7 ng/(g·hr))(P=0.006),and there were no significant differences in total BVOC emission rates between apple and peach trees.These findings contribute to our understanding on BVOC emissions from different plant organs and provide important insights into the variation of BVOC emissions across different fruit developmental stages.

Emerging challenges of ozone impacts on asian plants:actions are needed to protect ecosystem health

Context:Ozone concentrations near the land surface are rising in Asia while they are declining or stagnating in Europe and North America.Ozone is the most widespread air pollutant negatively affecting vegetation,and its increased concentrations pose a major threat to food quality and production and other ecosystem services in Asia.Method:In this review,we provide an overview of scientific challenges in the impacts of ozone pollution on Asian vegetation,and synthesize the challenges toward mitigation of the impacts.Result:We argue that new policy initiatives need to seek both reduction of ozone levels and enhancement of plant tolerance to ozone to maintain food quality and ensure food supplies.Conclusion:The scientific advancements must be transferred to actions by two types of institutions:a)environmental agencies for reducing ozone levels and b)agricultural research institutions for enhancing plant tolerance to ozone.In connecting the scientific advancements with the institutional actions,scientists in Asian countries should play the key role taking advantages of interdisciplinary and international collaborations.