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Correctly quantifying elevated air temperature effects on crop yield through field experiments and crop modeling is essential for developing adaptation strategies under climate change. In this study, the effects of elevated air temperature on soybean [Glycine max (L.) Merr.] production were investigated using a four-year open top chamber experiment (2015-2018) in North Carolina, USA. The experimental results showed that an increase of average air temperature during growing seasons by 3.4 • C to 25.7 • C decreased seed yield by 22%, final biomass by 11%, and harvest index by 12%, but did not significantly affect maturity date. The reduction in seed yield was more associated with reduction in seed number (19%) than in seed weight (2%). Two soybean growth models (CROPGRO and HER-MES) in the Root Zone Water Quality Model (RZWQM) were evaluated against measured temperature responses from the four-year experiment. Both crop models simulated lower reduction in seed yield (15% for CROPGRO and 17% for HER-MES), but simulated reduction in biomass was lower by CROPGRO (7%) and higher by HERMES (20%) than that measured in the chambers. Between the two models, HERMES predicted slightly better responses of seed yield and biomass to temperature across the four years than CROPGRO, whereas the opposite was true for maturity date and harvest index. However, HERMES simulated earlier maturity dates for heated treatment than observed, suggesting that improvements are needed in the model for soybean phenology response to temperature increase.

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A precisely timed irrigation schedule to match crop water demand is vital to improving water use efficiency in arid farmland. In this study, a real-time irrigation-scheduling infrastructure, Decision Support System for Irrigation Scheduling (DSSIS), based on water stresses predicted by an agro-hydrological model, was constructed and evaluated. The DSSIS employed the Root Zone Water Quality Model (RZWQM2) to predict crop water stresses and soil water content, which were used to trigger irrigation and calculate irrigation amount, respectively, along with forecasted rainfall. The new DSSIS was evaluated through a cotton field experiment in Xinjiang, China in 2016 and 2017. Three irrigation scheduling methods (DSSIS-based (D), soil moisture sensor-based (S), and conventional experience-based (E)), factorially combined with two irrigation rates (full irrigation (FI), and deficit irrigation (DI, 75% of FI)) were compared. The DSSIS significantly increased water productivity (WP) by 26% and 65.7%, compared to sensor-based and experience-based irrigation scheduling methods (p < 0.05), respectively. No significant difference was observed in WP between full and deficit irrigation treatments. In addition, the DSSIS showed economic advantage over sensor- and experience-based methods. Our results suggested that DSSIS is a promising tool for irrigation scheduling.

As animals evolved to use oxygen as the main strategy to produce ATP through the process of mitochondrial oxidative phosphorylation, the ability to adapt to fluctuating oxygen concentrations is a crucial component of evolutionary pressure. Three mitophagy receptors, FUNDC1, BNIP3 and NIX, induce the removal of dysfunctional mitochondria (mitophagy) under prolonged hypoxic conditions in mammalian cells, to maintain oxygen homeostasis and prevent cell death. However, the evolutionary origins and structure-function relationships of these receptors remain poorly understood. Here, we found that FUN14 domain-containing proteins are present in archaeal, bacterial and eukaryotic genomes, while the family of BNIP3 domain-containing proteins evolved from early animals. We investigated conservation patterns of the critical amino acid residues of the human mitophagy receptors. These residues are involved in receptor regulation, mainly through phosphorylation, and in interaction with LC3 on the phagophore. Whereas FUNDC1 may be able to bind to LC3 under the control of post-translational regulations during the early evolution of vertebrates, BINP3 and NIX had already gained the ability for LC3 binding in early invertebrates. Moreover, FUNDC1 and BNIP3 each lack a layer of phosphorylation regulation in fishes that is conserved in land vertebrates. Molecular evolutionary analysis revealed that BNIP3 and NIX, as the targets of oxygen sensing HIF-1α, showed higher rates of substitution in fishes than in mammals. Conversely, FUNDC1 and its regulator MARCH5 showed higher rates of substitution in mammals. Thus, we postulate that the structural traces of mitophagy receptors in land vertebrates and fishes may reflect the process of vertebrate transition from water onto land, during which the changes in atmospheric oxygen concentrations acted as a selection force in vertebrate evolution. In conclusion, our study, combined with previous experimental results, shows that hypoxia-induced mitophagy regulated by FUDNC1/MARCH5 might use a different mechanism from the HIF-1α-dependent mitophagy regulated by BNIP3/NIX.