@article{livingston_tuong_tisdale_zobel_2022, title={Visualising the effect of freezing on the vascular system of wheat in three dimensions by in-block imaging of dye-infiltrated plants}, ISSN={["1365-2818"]}, DOI={10.1111/jmi.13101}, abstractNote={Abstract}, journal={JOURNAL OF MICROSCOPY}, author={Livingston, David and Tuong, Tan and Tisdale, Ripley and Zobel, Rich}, year={2022}, month={Apr} }
 @article{tisdale_zobel_burkey_2021, title={Tropospheric ozone rapidly decreases root growth by altering carbon metabolism and detoxification capability in growing soybean roots}, volume={766}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2020.144292}, abstractNote={High tropospheric ozone (O3) concentrations lead to significant global soybean (Glycine max) yield reductions. Research concerning O3 impacts on soybean has focused on the contributions of above-ground tissues. In this study, Mandarin (Ottawa) (O3-sensitive) and Fiskeby III (O3-tolerant) soybean genotypes provide contrasting materials to investigate O3 effects on root growth. We compared root morphological and proteomic changes when 16-day-old plants were treated with charcoal-filtered (CF) air or elevated O3 (80 ppb O3 for 7 h/day) in continuously stirred-tank reactors (CSTR) for 7 days. Our results showed that in Mandarin (Ottawa), decreased expression of enzymes involved in the tricarboxylic acid (TCA) cycle contributes to reduction of root biomass and diameter under elevated O3. In contrast, O3 tolerance in Fiskeby III roots was associated with O3-dependent induction of enzymes involved in glycolysis and O3-independent expression of enzymes involved in the ascorbate-glutathione cycle. We conclude that a decreased abundance of key redox enzymes in roots due to limited carbon availability rapidly alters root growth under O3 stress. However, maintaining a high abundance of enzymes associated with redox status and detoxification capability contributes to overall O3 tolerance in roots.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Tisdale, Ripley H. and Zobel, Richard W. and Burkey, Kent O.}, year={2021}, month={Apr} }
 @article{qiu_guo_xu_zhang_zhang_chen_zhao_burkey_shew_zobel_et al._2021, title={Warming and elevated ozone induce tradeoffs between fine roots and mycorrhizal fungi and stimulate organic carbon decomposition}, volume={7}, ISSN={["2375-2548"]}, DOI={10.1126/sciadv.abe9256}, abstractNote={Warming and elevated ozone alter root traits and mycorrhizal fungal community and stimulate organic carbon decomposition.}, number={28}, journal={SCIENCE ADVANCES}, author={Qiu, Yunpeng and Guo, Lijin and Xu, Xinyu and Zhang, Lin and Zhang, Kangcheng and Chen, Mengfei and Zhao, Yexin and Burkey, Kent O. and Shew, H. David and Zobel, Richard W. and et al.}, year={2021}, month={Jul} }
 @article{burkey_tisdale_zobel_ray_pursley_2020, title={Interactive Effects of Elevated Ozone and Temperature on Growth and Yield of Soybean (Glycine max (L.) Merr.) under Field Conditions}, volume={10}, ISSN={["2073-4395"]}, DOI={10.3390/agronomy10111803}, abstractNote={Elevated ozone and rising temperature are both factors in climate change, but they are difficult to study in combination due to exposure system requirements. We developed and deployed an air exclusion exposure system to treat soybean (Glycine max (L.) Merr.) cultivar “Jake” with season-long combinations of sub-ambient ozone (18 ppb, 12 h mean), elevated ozone (66 ppb, 12 h mean), and elevated temperature (+3.5 °C daytime, +2.4 °C nighttime) in irrigated field plots. Warming caused a shift in biomass partitioning from reproductive tissues into stems and petioles at mid-season that resulted in a significant 25% reduction in final seed yield and a significant reduction in harvest index. The elevated ozone treatment delayed mid-season biomass production, and final seed yield was reduced by a non-significant 2%. However, there were significant underlying effects of elevated ozone on seed production. The non-significant impact of ozone on seed yield of cultivar “Jake” resulted from significant increases in pod number (+16%) and seed number (+18%) that were offset by a significant reduction in seed size (−16%). No evidence of significant warming–ozone interactions was found in biomass or seed yield responses. In general, significant impacts of the individual warming or ozone treatments were found to be additive.}, number={11}, journal={AGRONOMY-BASEL}, author={Burkey, Kent and Tisdale, Ripley and Zobel, Richard and Ray, Samuel and Pursley, Walter}, year={2020}, month={Nov} }
 @article{abdallah_mashaheet_zobel_burkey_2019, title={Physiological basis for controlling water consumption by two snap beans genotypes using different anti-transpirants}, volume={214}, ISSN={["1873-2283"]}, DOI={10.1016/j.agwat.2018.12.029}, abstractNote={Enhancing water use efficiency (WUE), while maintaining productivity, represents a challenge, particularly, in arid and semi-arid environments. The use Antitranspirants (ATs) is an effective approach to mitigate water deficit- and drought-induced yield losses, via reducing transpiration. This study aimed to determine the effects of ATs compounds on WUE and root and shoot physiological responses of two snap bean genotypes with different ozone sensitivity [tolerant (R123) and sensitive (S156)]. Under glasshouse conditions, plants were sprayed (25 days after planting) with 4% (w/v) kaolin (KPF); 0.0015% (w/v) Fulvic acid (FA); 1% (v/v) Pinolene (PIN) or water (control). Treatments were subjected to three irrigation/drying cycles, and then exposed to survivability test by ceasing irrigation. Water consumption (WC), leaf water potential (Ψw), total dry matter (TDM), dry matter accumulation rate (DMAR), leaf temperature, plant survival and root development were determined. There was a minimal genotype effect on all parameters, except TDM, DMAR, and fine-root diameter and length. KPF treatment was cooler than the control (<3.83 °C), consequently, had higher Ψw and lower WC, without affecting TDM and DMAR. Therefore, biomass-WUE (total dry matter/transpired water) of KPF treatment increased (29.4% and 13.3% for R123 and S156, respectively). Pinolene and FA treatments exerted no effects on those parameters. KPF treatment alleviated most of the physiological effects of water deficit, hence plants survived longer. KPF and FA treatments had thicker very fine (0.0726 to 0.29 mm) and fine (0.308 to 0.562 mm) roots than the control, with KPF having the strongest effect on roots development. Pinolene treatment showed no effect on the roots of R123, but conditioned significant thickening of S156 roots; a notable reversal of the observed effect of KPF and FA. In conclusion, conserved water by KPF, could reduce irrigation frequency and, later, play as a crucial water resource for plant survival. Moreover, future research with ATs must take root responses into account.}, journal={AGRICULTURAL WATER MANAGEMENT}, author={AbdAllah, Ahmed M. and Mashaheet, Alsayed M. and Zobel, Richard and Burkey, Kent O.}, year={2019}, month={Apr}, pages={17–27} }
 @article{qiu_jiang_guo_zhang_burkey_zobel_reberg-horton_shew_hui_2019, title={Shifts in the Composition and Activities of Denitrifiers Dominate CO2 Stimulation of N2O Emissions}, volume={53}, ISSN={["1520-5851"]}, DOI={10.1021/acs.est.9b02983}, abstractNote={Elevated atmospheric CO2 (eCO2) often increases soil N2O emissions but the underlying mechanisms remain largely unknown. One hypothesis suggests that high N2O emissions may stem from increased denitrification induced by CO2-enhancement of plant carbon (C) allocation belowground. However, direct evidence illustrating linkages among N2O emissions, plant C allocation and denitrifying microbes under eCO2 is still lacking. We examined the impact of eCO2 on plant C allocation to roots and their associated arbuscular mycorrhizal fungi (AMF) and its subsequent effects on N2O emissions and denitrifying microbes in the presence of two distinct N sources, ammonium nitrogen (NH4+- N) and nitrate nitrogen (NO3--N). Our results showed that the form of the N inputs dominated the effects of eCO2 on N2O emissions: eCO2 significantly increased N2O emissions with NO3--N inputs but had no effect with NH4+-N inputs. eCO2 increased plant biomass N more with NH4+-N than NO3--N inputs, likely reducing microbial access to available N under NH4+-N inputs and/or contributing to higher N2O emissions under NO3--N inputs. While eCO2 enhanced root and mycorrhizal N uptake, it also increased N2O emissions under NO3--N inputs. Further, eCO2-enhancement of N2O emissions under NO3--N inputs concurred with a shift in the soil denitrifier community composition in favor of N2O-producing (nirK- and nirS-type) over N2O-consuming (nosZ-type) denitrifiers. Together, these results indicate that eCO2 stimulated N2O emissions mainly through altering plant N preference in favor of NH4+ over NO3- and thus stimulating soil denitrifiers and their activities. These findings suggest that effective management of N sources may mitigate N2O emissions by negating eCO2-stimulation of soil denitrifying microbes and their activities.}, number={19}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Qiu, Yunpeng and Jiang, Yu and Guo, Lijin and Zhang, Lin and Burkey, Kent O. and Zobel, Richard W. and Reberg-Horton, S. Chris and Shew, H. David and Hui, Shuijin}, year={2019}, month={Oct}, pages={11204–11213} }
 @article{qu_jiang_guo_burkey_zobel_shew_hu_2018, title={Contrasting Warming and Ozone Effects on Denitrifiers Dominate Soil N2O Emissions}, volume={52}, ISSN={["1520-5851"]}, DOI={10.1021/acs.est.8b01093}, abstractNote={Nitrous oxide (N2O) in the atmosphere is a major greenhouse gas and reacts with volatile organic compounds to create ozone (an air pollutant) in the troposphere. Climate change factors such as warming and elevated ozone (eO3) affect N2O fluxes, but the direction and magnitude of these effects are uncertain and the underlying mechanisms remain unclear. We examined the impact of simulated warming (control + 3.6 °C) and eO3 (control + 45 ppb) on soil N2O fluxes in a soybean agroecosystem. Results obtained showed that warming significantly increased soil labile C, microbial biomass, and soil N mineralization, but eO3 reduced these parameters. Warming enhanced N2O-producing denitrifers ( nirS- and nirK-type), corresponding to increases in both the rate and sum of N2O emissions. In contrast, eO3 significantly reduced both N2O-producing and N2O-consuming ( nosZ-type) denitrifiers but had no impact on N2O emissions. Further, eO3 offsets the effects of warming on soil labile C, microbial biomass, and the population size of denitrifiers but still increased N2O emissions, indicating a direct effect of temperature on N2O emissions. Together, these findings suggest that warming may promote N2O production through increasing both the abundance and activities of N2O-producing microbes, positively feeding back to the ongoing climate change.}, number={19}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Qu, Yunpeng and Jiang, Yu and Guo, Lijin and Burkey, Kent O. and Zobel, Richard W. and Shew, H. David and Hu, Shuijin}, year={2018}, month={Oct}, pages={10956–10966} }