Unbounding the Future: Designing NiAl-based Catalysts for Dry Reforming of Methane.

Dry reforming of methane (DRM), the catalytic conversion of CH4 and CO2 into syngas (H2 + CO), is an important process closely correlated to the environment and chemical industry. NiAl-based catalysts have been reported to exhibit excellent activity, low cost, and environmental friendliness. At the same time, the rapid deactivation caused by carbon deposition, Ni sintering, and phase transformation exerts great challenges for its large-scale applications. This review summarizes the recent advances in NiAl-based catalysts for DRM, particularly focusing on the strategies to construct efficient and stable NiAl-based catalysts. Firstly, the thermodynamics and elementary steps of DRM, including the activation of reactants and coke formation and elimination, are summarized. The roles of Al2O3 and its mixed oxides as the support, and the influences of the promoters employed in NiAl-based catalysts over the DRM performance, are then illustrated. Finally, the design of anti-coking and anti-sintering NiAl-based catalysts for DRM is suggested as feasible and promising by tailoring the structure and states of Ni and the modification of Al-based supports including small Ni size, high Ni dispersion, proper basicity, strong metal-support interaction (SMSI), active oxygen species as well as high phase stability.

Why cuckoos remove host eggs: Biting eggs facilitates faster parasitic egg-laying.

Brood parasitism by cuckoos relies on manipulating hosts to raise their offspring and has evolved stunning adaptations to aid in their deception. The fact that cuckoos usually but not always, remove one or two host eggs while laying their eggs has been a longstanding focus of intensive research. However, the benefit of this behavior remains elusive. Moreover, the recently proposed help delivery hypothesis, predicting that egg removal by cuckoos may decrease the egg-laying duration in the parasitism process caused by biting action, lacks experimental verification. Therefore, in this study, we examined the effects of egg removal/biting on the egg-laying speed in the common cuckoo (Cuculus canorus) to experimentally test this hypothesis. We compared the duration of cuckoo egg-laying in empty nests, nests with host eggs, and nests with artificial blue stick models to test whether cuckoos biting an egg/stick can significantly hasten the egg-laying speed than no biting action. Our results showed that biting an egg or an object is associated with cuckoos laying approximately 37% faster than when they do not bite an egg or an object. This study provides the first experimental evidence for the help delivery hypothesis and demonstrates that when cuckoos bite eggs or other objects in the nest, they lay eggs more quickly and thereby avoid suffering the hosts' injurious attack.

Nest desertion as an anti-parasitism strategy in hosts selects for late egg-laying behavior in cuckoos.

Studies have shown that brood parasites lay their eggs early in the egg-laying sequence of their hosts, providing them with the advantage of earlier hatching. However, common cuckoos (Cuculus canorus) appear to parasitize the nests of gray bushchat (Saxicola ferreus) during the late egg-laying stage. The bushchat often abandons parasitized nests in the early stages, but not in the late egg-laying stages, thus favoring late egg-laying by cuckoos. In this study, four experiments were conducted to determine whether gray bushchats employ a nest desertion strategy targeted at cuckoo parasitism. The results showed that nest desertion was significantly correlated with parasitism cues and occurred mainly during the hosts' early egg-laying stage. Our study provides the first experimental evidence that nest desertion is an anti-parasitic strategy used by hosts in response to cuckoos. Additionally, our experiments demonstrated that the nest desertion is influenced by the trade-offs of investments in different egg-laying stages.

Occurrence and Chemical Control Strategy of Wheat Brown Foot Rot Caused by Microdochium majus.

Wheat brown foot rot (WBFR), caused by a variety of phytopathogenic fungi, is an important soilborne and seedborne disease of wheat. WBFR causes wheat lodging and seedling dieback, which seriously affect the yield and quality of wheat. In this study, 64 isolates of WBFR were isolated from different wheat fields in Yancheng city, Jiangsu Province, China. The internal transcribed spacer, elongation factor 1α, and RNA polymerase II subunit were amplified and the sequencing results of the fragments were analyzed with BLAST in NCBI. Through morphological and molecular identification, all of the isolates were identified as Microdochium majus. Verification by Koch's postulates confirmed that M. majus was the pathogen causing WBFR. The antifungal activities of fludioxonil and prochloraz against 64 isolates of M. majus were determined based on mycelial growth inhibition method. The results showed that fludioxonil and prochloraz had good antifungal activity against M. majus. The mean 50% effective concentration values of fludioxonil and prochloraz against M. majus were 0.2956 ± 0.1285 µg/ml and 0.0422 ± 0.0157 µg/ml, respectively. Control efficacy for seed-coating treatments conducted in a greenhouse indicated that M. majus severely damaged the normal growth of wheat, while seed coating with fludioxonil or prochloraz significantly reduced the disease incidence and improved the seedling survival rates. At fludioxonil doses of 7.5 g per 100 kg and prochloraz doses of 15 g per 100 kg, the incidence was reduced by 22.26 and 25.33%, seedling survival rates increased by 25.37 and 22.66%, and control efficacy reached 70.02 and 72.30%, respectively. These findings provide vital information for the accurate diagnosis and effective management of WBFR.

Predation of Daurian redstarts offspring in nest boxes by the Oriental magpie-robin and tree sparrow.

Birds select suitable nest sites for breeding to ensure their own and offspring's survival; however, they inevitably suffer some potential predation risk. We studied the breeding ecology of Daurian redstarts (Phoenicurus auroreus) by providing nest boxes for their breeding from March to August of 2022. We recorded the predation of both Daurian redstarts eggs or nestlings by Oriental magpie-robins (Copsychus saularis) and tree sparrow (Passer montanus). Oriental magpie-robin were recorded attacking a feeding female adult and depredating nestlings. After the nestling predation event, the Daurian redstarts abandoned the nest. This video evidence provide a better understanding of the potential predators of cavity-nesting birds.

Importance of cooperation: How host nest defenses effectively prevent brood parasitism from the cuckoos.

As the frontline defense against avian brood parasitism, nest defense is important in reducing nest parasitism and increasing host fitness. However, systematic studies on its effectiveness (i.e., on whether it successfully prevents cuckoo parasitism) are scarce. Based on 214 video recordings from 10 years of field observations, we evaluated the effectiveness of nest defenses of the Oriental reed warbler (Acrocephalus orientalis) in deterring common cuckoo (Cuculus canorus) parasitism. Under a breeding pair situation (≤ 2 hosts individuals), warblers were hardly effective in resisting the egg-laying of the cuckoo and many of the cuckoos under attack were able to complete the parasitic process without being harmed. However, when hosts ≥ 3 individuals, the warblers could effectively thwart the cuckoos and cause lethal damage to the cuckoo in partial cases. This indicated that the host group effectively resisted the cuckoo, demonstrating the importance of cooperation among host neighbors in resisting cuckoo parasitism.

Fatal mobbing and attack of the common cuckoo by its warbler hosts.

Nest defense is an effective strategy of hosts against parasites. Typically, hosts will aggressively attack brood parasites that approach or visit their nests, which can prevent the parasites from laying eggs or may even lead to the death of the parasites. Few previous studies have specifically reported such fatal cases involving brood parasites and have attributed the cause of death to either drowning or hypothermia after falling into the water following an attack from hosts. In this study, we recorded the process of multiple host individuals of the Oriental reed warbler (Acrocephalus orientalis) mobbing and attacking a female common cuckoo (Cuculus canorus) in the field. We discovered that the immediate cause of the cuckoo's death was the fatal physical damage resulting from the aggressive defense from the hosts, suggesting that frantic pecking and scratching by the hosts is the most proximate cause of mortality among egg-laying female cuckoos. This finding enhances our essential understanding of the effectiveness of host attacks.

Mechanism of Fusarium graminearum Resistance to Ergosterol Biosynthesis Inhibitors: G443S Substitution of the Drug Target FgCYP51A.

Fusarium head blight (FHB), caused by the Fusarium graminearum species complex, is a devastating fungal disease resulting in substantial yield and quality losses. Ergosterol biosynthesis inhibitors (EBIs) are the most popular chemicals for controlling FHB. Recently, the resistance of F. graminearum to EBIs has emerged in the field, and an amino acid substitution (G443S) of the sterol 14α-demethylase FgCYP51A was detected in the field resistant strains. To further illustrate the resistance mechanism of F. graminearum to EBIs, site-directed mutants conferring the G443S substitution of FgCYP51A were generated from the progenitor strain PH-1 via genetic transformation with site-directed mutagenesis. We found that the FgCYP51A-G443S substitution significantly decreased the sensitivity of F. graminearum to EBIs with EC50 values ranging from 0.1190 to 0.2302 µg mL-1 and EC90 values ranging from 1.3420 to 9.1119 µg mL-1 for tebuconazole. Furthermore, the FgCYP51A-G443S substitution decreased sexual reproduction and virulence, which will reduce the initial infection source of pathogen populations in the field, while the increase of sporulation capability may enhance the frequencies of the disease cycle, thereby contributing to epidemics of FHB disease. Surprisingly, the FgCYP51A-G443S substitution accelerated DON biosynthesis by upregulating TRI5 expression and enhancing the fluorescence intensity of TRI1-GFP, the marker protein of Fusarium toxisomes. Thus, we concluded that the FgCYP51A-G443S substitution regulates EBI-fungicide resistance and DON biosynthesis, increasing the risk of fungicide resistance development in the field, thereby threatening the control efficacy of EBIs against FHB.

Antifungal Activity and Biological Characteristics of the Novel Fungicide Quinofumelin Against Sclerotinia sclerotiorum.

Sclerotinia sclerotiorum is a devastating plant pathogen with a broad host range and worldwide distribution. The application of chemical fungicides is a primary strategy for controlling this pathogen. However, under the high selective pressure of chemical fungicides, fungicide resistance has emerged and gradually increased, resulting in the failure to control S. sclerotiorum in the field. Quinofumelin is a novel quinoline fungicide, but its antifungal activities against plant pathogens have been rarely reported. Here, we determined the antifungal activity of quinofumelin against S. sclerotiorum in vitro and in planta. The median effect concentration (EC50) values ranged from 0.0004 to 0.0059 µg ml-1 with a mean EC50 of 0.0017 ± 0.0009 µg ml-1 and were normally distributed (P = 0.402). In addition, no cross resistance was observed between quinofumelin and other fungicides, dimethachlone, boscalid, or carbendazim, which are commonly used to manage S. sclerotiorum. Quinofumelin did not affect glycerol and oxalic acid production of either carbendazim-sensitive or -resistant isolates. Moreover, quinofumelin exhibited excellent protective, curative, and translaminar activity against S. sclerotiorum on oilseed rape leaves. Protective activity was higher than curative activity. Interestingly, quinofumelin inhibited the formation of the infection cushion in S. sclerotiorum, which may contribute to the control efficacy of quinofumelin against S. sclerotiorum in the field. Our findings indicate that quinofumelin has excellent control efficacy against S. sclerotiorum in vitro and in planta as compared with extensively used fungicides and could be used to manage carbendazim- and dimethachlone-resistance in S. sclerotiorum in the field.

Quinone outside inhibitors affect DON biosynthesis, mitochondrial structure and toxisome formation in Fusarium graminearum.

Quinone outside inhibitors (QoIs) are currently extensively used agricultural fungicides. However, the application of QoIs in controlling Fusarium graminearum was rarely reported. No information is available on pharmacological characteristics of QoIs against F. graminearum, as well as their effects on DON biosynthesis. Here, we found that six QoIs exhibited an excellent fungicidal activity against F. graminearum based on mycelial growth and spore germination. ATP production assay further confirmed that QoIs decreased ATP production via inhibiting mitochondrial respiration, which contributes their fungicidal activity. Unfortunately, QoIs can stimulate DON production and up-regulate the expression of Tri5 and Tri6 genes. Additionally, acetyl-CoA, the basic precursor of DON biosynthesis, significantly increased as affected by QoIs, furtherly indicating that QoIs indeed enhance DON biosynthesis. We also found that QoIs can accelerate the formation of toxisomes and enhance the fluorescence signals of Tri-GFP labeled toxisomes, which may be due to the effect of QoIs on toxisome-related endoplasmic reticulum-remodeling. In addition, QoIs could disrupt the homeostasis of mitochondrial dynamics, resulting in the fragmented mitochondria. Finally, the simulated inoculation assay with wheat grains further verified that QoIs can stimulate DON production relative to wheat grain weight, especially relative to mycelial biomass.

Activity of Demethylation Inhibitor Fungicide Metconazole on Chinese Fusarium graminearum Species Complex and Its Application in Carbendazim-Resistance Management of Fusarium Head Blight in Wheat.

Fusarium graminearum species complex (FGSC), causing Fusarium head blight (FHB) of wheat, has species-specific geographical distributions in wheat-growing regions. In recent years, benzimidazole resistance of FHB pathogens has been largely widespread in China. Although the demethylation inhibitor fungicide metconazole has been used for FHB control in some countries, no information about metconazole sensitivity of Chinese FHB pathogen populations and efficacy of metconazole in FHB control in China is available. In this study, the sensitivity of FGSC to metconazole was measured with 32 carbendazim-sensitive strains and 35 carbendazim-resistant strains based on mycelial growth. The 50% effective concentration values of 67 strains were normally distributed and ranged from 0.0209 to 0.0838 µg ml-1, with a mean of 0.0481 ± 0.0134 µg ml-1. No significant difference in metconazole sensitivity was observed between carbendazim-sensitive and -resistant populations. An interactive effect of metconazole and phenamacril, a novel cyanoacrilate fungicide approved in China against Fusarium spp., in inhibiting mycelial growth showed an additive interaction at different ratios. Furthermore, field trials to evaluate the effect of metconazole and metconazole + phenamacril treatments in FHB control, deoxynivalenol (DON) production, and grain yields were performed. Compared with the fungicides carbendazim and phenamacril currently used in China, metconazole exhibits a better efficacy for FHB control, DON production, and grain yields, and dramatically reduces use dosages of chemical compounds in the field. The mixture of metconazole and phenamacril at ratios of 2:3 and 1:2 showed the greatest efficacy for FHB control, DON production, and grain yields among all the fungicide treatments but its use dosages were higher in comparison with metconazole alone. In addition, FHB control, grain yields, and DON levels were significantly correlated with each other, showing that visual disease indices can be used as an indicator of grain yields and DON contamination. Meanwhile, the frequency of carbendazim-resistant alleles in F. graminearum populations was dramatically reduced after metconazole and phenamacril alone and the mixture of metconazole and phenamacril applications, indicating that metconazole and a mixture of metconazole and phenamacril can be used for carbendazim resistance management of FHB in wheat. Overall, the findings of this study provide important data for resistance management of FHB and reducing DON contamination in wheat grains.

Facile synthesis of ordered mesoporous zinc alumina catalysts and their dehydrogenation behavior.

Ordered mesoporous Zn/Al2O3 materials with varying Zn content were simply prepared via an evaporation-induced self-assembly (EISA) method. Dehydrogenation of isobutane to isobutene was carried out on these materials; an isobutane conversion of 45.0% and isobutene yield of 39.0% were obtained over the 10%Zn/Al2O3 catalyst at 580 °C with 300 h-1 GHSV. The obtained materials with Zn content up to 10% possess large specific surface area and big pore volume and zinc species can be highly dispersed on the surface or incorporated into the framework. The acidity of these catalysts was changed by the introduction of Zn, the decrease of strong acid sites is conducive to the promotion of isobutene selectivity and the weak and medium acidic sites played an important role in isobutane conversion. In addition, these catalysts exhibited good catalytic stability, due to the effective inhibition of coke formation by the ordered mesoporous structure.

Molecular and biological characteristics of laboratory metconazole-resistant mutants in Fusarium graminearum.

The Fusarium graminearum species complex (FGSC), the causal agents of Fusarium head blight (FHB) in wheat, has the different geographically distributed species. Our previous study suggested that a DMI fungicide metconazole exhibits a strong fungicidal activity in mycelial growth of Chinese FHB pathogens and metconazole is currently a most effective compound of commercial fungicides for controlling FHB in China. In the current study, metconazole-resistant F. graminearum mutants were induced by chemical taming and their molecular and biological characteristics were determined. Compared to the corresponding parental strains, three mutation genotypes (two single mutations G443S and D243N, and a combined mutation E103Q&V157 L) were observed in the FgCYP51A of metconazole-resistant mutants. In addition to FgCYP51A mutation, all the mutants had no change on sequences of FgCYP51B and FgCYP51C and promotor sequences of FgCYP51s, but expression patterns of FgCYP51s were different. Compared to the corresponding parental strains, overexpression of FgCYP51A, FgCYP51B and FgCYP51C was observed in the mutant conferring D243N mutation, overexpression of FgCYP51A and FgCYP51B was observed in the mutant conferring E103Q&V157L mutations, and overexpression of FgCYP51A was observed in the mutant conferring G443S mutation. Biological fitness of the mutants conferring D243N mutation or E103Q&V157 L mutations significantly decreased in comparison to the corresponding parental strains, suggesting a fitness penalty. The mutants conferring G443S mutation had no change in biological fitness as compared with the parental strain, indicating that the G443S mutation may emerge in field resistant populations of F. graminearum in the future. In addition, a positive cross resistance between metconazole and other tested DMI fungicides was observed in the mutants conferring D243N mutation or E103Q&V157L mutations, but no cross resistance between metconazole and ipconazole or prochloraz was observed in the mutants conferring G443S mutation. Therefore, we concluded that the mutation genotype of FgCYP51A may cause the differences of biological fitness, cross-resistance and FgCYP51s overexpression patterns. Such information will increase our understanding of resistance mechanism of F. graminearum to DMIs and could provide new reference data for the management of FHB.

Mesoporous Mn-Zr composite oxides with a crystalline wall: synthesis, characterization and application.

Mesoporous Mn-Zr composite oxides (M-MnZr) with a crystalline wall were designed and achieved by a facile one-pot evaporation-induced self-assembly (EISA) strategy. As proved by XRD, HRTEM and SAED characterization, the wall of the obtained mesoporous materials exhibited a typical tetragonal phase of ZrO2. In addition, the introduced manganese species were homogeneously dispersed in the mesoporous skeleton. N2-physisorption and TEM results showed that all the final materials possessed an obvious mesoporous structure accompanied by a large specific surface area (∼120 m(2) g(-1)), big pore volume (∼0.2 cm(3) g(-1)) and uniform pore size (∼4.9 nm). In addition, the liquid phase oxidation was chosen as the test reaction and the excellent catalytic performance of M-MnZr demonstrated their potential applications in oxidation reactions.