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Little research was carried out to study the effect of water vapor with different contents on the CO2 adsorption performance during extending cycles in both carbonation and decarbonation stages. This study described the CO2 adsorption performance of Ca-Al mixed oxides under different water vapor concentrations. The results revealed that the reactivity and durability of both fresh and spent sorbents were remarkably enhanced by adding water vapor. The initial CO2 carbonation capacity increased from 56 wt% without water to 70.7 wt% with 1.6% water vapor at the adsorption temperature of 600 °C. The stability of Ca-Al mixed oxides was also investigated during 220 cycles with 1% steam vapor. The CO2 adsorption capacity retained 55.6 wt% after 220 cycles, indicating an excellent long-term durability. The excellent CO2 adsorption capacity and stability of the mixed oxides in the existence of water vapor may be attributed to the following reasons: water vapor facilitated CO2 diffusion in the CaCO3 product layer during the carbonation stage as well as the decomposition rate of CaCO3 during the calcination stage; water vapor facilated the formation of the loose porous structure, which was favorable for the subsequent carbonation of CaO.

The miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors play key roles in regulating plant development, but little is known about their function in abscisic acid (ABA) signaling. Here, we report that the miR156-targeted SPLs enhance ABA responses and contribute to the inhibition of pre-harvest sprouting. We find that SPL9 directly activates the expression of ABA responsive genes through binding to their promoters. SPL9 was further shown to physically interact with ABSCISIC ACID INSENSITIVE 5 (ABI5), a master transcription factor in ABA signaling, thus promoting its association with the promoters of ABA responsive genes. Furthermore, we reveal that the protein kinases SnRK2s interact with and phosphorylate SPL9, which is essential for its role in the activation of ABA responses. Together, our results disclose a SnRK2s-SPLs-ABI5 regulatory module in ABA signaling inArabidopsis.

Plants reduce their growth rate when confronted by insect attack, and in turn resources are redirected from growth to enhance resistance against herbivory. In this study, one possible signaling cascade was investigated for establishing the underlying mechanism for the slow growth rate that has been observed following insect herbivory. Our results showed that free jasmonate (JA) and auxin levels were elevated in both leaves and roots after Plutella xylostella L. attack which was accompanied by the transcriptional increase of the auxin biosynthetic YUCCA3 and YUCCA8 genes. Further examination of endogenous auxin flux using physiological micro-sensor profiling showed that near the surface of the root transition zone, the net auxin flux decreased after insect attack. Conversely, insect herbivory caused an increase in the net H+ flux along the root surface with the most pronounced response occurring in the transition zone. Transcript levels of auxin transporter genes PIN1, PIN2, PIN3, PIN7, and AUX1 were also reduced after insect attack. Together, the auxin and H+ flux results indicate that the reduced growth after insect attack was likely associated with a decrease of auxin flux and proton secretion along the root tip.

Summary Plant height is among the most important agronomic traits that influence crop yield. However, in addition to the Rht‐1 alleles, the molecular basis of plant height in bread wheat remains largely unclear. Based on wheat gene expression profiling analysis, we identify a light‐regulated gene from bread wheat, designated as TaCOLD1, whose encoding protein is homologous to cold sensor COLD1 in rice. We show that TaCOLD1 protein is localized to the endoplasmic reticulum (ER) and plasma membrane. Phenotypic analyses show that overexpression of a mutated form of TaCOLD1 (M187K) in bread wheat cultivar Kenong199 (Rht‐B1b) background resulted in an obvious reduction in plant height. Further, we demonstrate that the hydrophilic loop of TaCOLD1 (residues 178–296) can interact with TaGα‐7A (the α subunit of heterotrimeric G protein) protein but not TaGα‐1B, and the mutation (M187K) in TaCOLD1 remarkably enhances its interaction with TaGα‐7A. Physical interaction analyses show that the C‐terminal region of TaGα‐7A, which is lacking in the TaGα‐1B protein, is necessary for its interaction with TaCOLD1. Intriguingly, the C‐terminal region of TaGα‐7A is also physically associated with the TaDEP1 protein (an atypical Gγ subunit). Significantly, we discover that TaCOLD1 and mTaCOLD1 (M187K) can interfere with the physical association between TaGα‐7A and TaDEP1. Together, this study reveals that TaCOLD1 acts as a novel regulator of plant height through interfering with the formation of heterotrimeric G protein complex in bread wheat and is a valuable target for the engineering of wheat plant architecture.

Biosynthesis and accumulation of jasmonate (JA) can regulate plant defense responses and organ development under insect herbivore stress conditions. One of these responses, the inhibition of root growth, is a common phenomenon. However, the physiological and molecular mechanisms of how JA affects root growth are not completely understood. In this study, the influence of MeJA treatment on auxin and proton flux rates in the root apex region of Col-0, coi1-1, pin2, and aux1-7 mutant lines was examined using a non-invasive micro-test technique. The auxin and H+ flux profiles taken from coi1-1 mutants suggest that the modulation of auxin and H+ flux by JA requires the function of COI1. The auxin and H+ flux in pin2 and aux1 mutants with and without JA treatment suggest that JA can affect polar auxin transport by regulating PIN-mediated auxin efflux and the AUX-mediated influx pathways. Furthermore, the expression levels of PIN1, PIN2, PIN3, PIN7, AUX1, and TIR1 genes were reduced under MeJA treatment, and expression levels of CYP79B2 and CYP79B3 were elevated. Together, these results suggest that JA signaling may modulate the auxin signaling pathways by regulating the expression of key genes.

In this paper, we studied the CO2 adsorption performances of well-mixed oxides with Ca/Al ratios of 2:1, 2.5:1, 3:1, 3.5:1, and 4:1, which were prepared through the thermal decomposition of co-precipitated hydrotalcite-like Ca–Al–ClO4 precursors. The mixed oxides with a Ca/Al ratio of 3 exhibited the best performance at the adsorption temperature of 600 °C, and approximately 87% of the initial CO2 capture capacity was retained after 50 cycles of multiple carbonation/calcination tests. The favorable cyclical performance of the adsorbent is attributed to the homogeneous distribution of Al2O3 among CaO particles, which effectively prevented the aggregation and sintering of CaO crystallite. Furthermore, a smaller particle size (about 30 nm) of CaO allowed for as much carbonation as possible to take place at the rapid reaction-controlled regime rather than at the diffusion-controlled regime, resulting in the favorable long-term adsorption performance.