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A two-year experiment was carried out at Shenyang Agricultural University's research field area in China to evaluate the impact of the combined application of straw mulch (0 and 8 t ha−1) and biochar (0, 4, 12, and 36 t ha−1) on the morphological traits and grain development of rainfed maize during 2018 and 2019. The results showed that straw mulch and different biochar application rates significantly impacted the maize growth index. Compared to non-biochar-treated soils, the introduction of straw mulch improved plant height, stem diameter, leaf area index (LAI), leaves, stem, root, and crop growth rate (CGR), and dry weight of rainfed maize crop. The highest plant height, stem diameter, LAI, leaves, stem, root growth rate, CGR, and dry weight of rainfed maize crop were reported when soil was treated with a higher rate of biochar (36 t ha−1). Biochar increased grain filling rate while decreasing grain filling duration in rainfed maize crops. Our results indicate that straw mulch and biochar-based soil management strategies can improve the rainfed maize growth with the environmental benefits of global warming mitigation. However, due to the wide range of biochar properties, the interactions between straw mulch and biochar should be given special consideration in the maize cropping system. [ABSTRACT FROM AUTHOR]

Global warming and climate alterations have adversely affected agricultural production systems. The application of biochar can help mitigate climate change impacts and enhance the production and quality of agriculture. The field experiments were conducted during 2018 and 2019 to evaluate the effects of straw mulch (0 and 8 tons ha-1) and biochar (0, 4, 12, and 36 tons ha-1) on soil temperature, soil pH, bulk density, electric conductivity, cation exchange capacity, soil organic carbon, soil nutrient status (available P, K, NO3-, and NH4+) at various soil depth (10, 20, and 30 cm), and yield and yield-related traits of rainfed maize (Zea mays L.). The results showed that addition of biochar regulated the soil temperature, pH, electrical conductivity, cation exchange capacity, and increased the soil organic carbon, soil nutrient status (available P, K, NO3-, and NH4+) compared to non-biochar-treated soils. In contrast, the higher amount of biochar (36 tons ha-1) application decreased the soil bulk density compared to control. However, the combined application of straw mulch and biochar improved the grain yield and yield contributing traits of maize. In conclusion, either straw mulch and biochar or combined straw mulch + biochar-based soil management techniques regulate the temperature and physiochemical properties of soil. These improvements in soil properties increased the grain yield of rainfed maize and help to mitigate global warming. [ABSTRACT FROM AUTHOR]

In order to quantitatively evaluate the impact of biochar on the yield of staple crops in China, a total of 866 pairs of data from 116 published studies were collected. Meta analysis was used to quantitatively analyze the impact of biochar on the yield of staple crops in China and its influencing factors. Meanwhile, a structural equation model (SEM) was constructed to further explain the interaction among the factors. The results showed that compared with no biochar application, biochar application could improve the physical and chemical properties of the soil in the main grain fields and increase the yield of the main grain crops, with an average yield increase rate of 8.77%. Among them, when the pH of biochar was 7-8, the average yield increase rate was the highest, reaching 26.49%. When C/N<60, the average yield increase rate was 13.73%, which was significantly higher than that of C/N≥60. Applying biochar to acidic or neutral soil could give full play to its yield-increasing effect. When the amount of carbon applied was 10-20 t·hm -2 , the average yield increase rate of wheat and corn was the highest. The average yield of rice was the highest when the amount of carbon was 15-25 t·hm -2 . However, the yield-increasing rates of rice with different carbon application levels were similar, so it is possible to consider losing part of the yield and give consideration to the economic benefits by appropriate reduction. In addition, the yield-increasing effect of biochar decreased with the increase in application years, and generally the yield-increasing effect was not significant after three years. The SEM showed that the application amount of biochar not only directly affected the yield of staple crops but also indirectly affected the yield of staple crops by improving soil fertility, whereas biochar C/N and pH only affected the yield of staple crops by improving soil fertility. Therefore, in the future application of biochar, priority should be given to applying it to acidic or neutral soil with low fertility, and its C/N and pH should be controlled below 60 and 7-8, respectively. Soil conditions, biochar characteristics, and field management measures should be comprehensively considered to maximize the yield of staple crops. This research can provide scientific basis and theoretical basis for the popularization and rational application of biochar.

A combination of LC-MS technology and activity evaluation was used to identify the antipyretic ingredients in rhubarb. The rat model of fever was established with dried yeast and then was administered ethanol extract and different polar fractions of rhubarb. Next, the anal temperature of these rats was measured and recorded at 0.5, 1, 2, 3, 4 and 5 h after administration, and the inhibition rate of each part on the rise of body temperature was calculated. The inhibition rate is higher and the antipyretic effect is better. The chemical composition of the effective fraction was analyzed with UPLC-ESI-Orbitrap-MS/MS technology. Compared with the model group, the increase of body temperature of ethanol extract group all reduced at each measurement time especially after 3 h, and the inhibition rate were 38.7%(P&lt;0.05), 78.2%(P&lt;0.01) and 72.4%(P&lt;0.01) at 3 h, 4 h, and 5 h after administration, respectively. Both n-butanol and water fraction showed some antipyretic activity in the early stage, with the inhibition rate of 28.1%(P&lt;0.01) and 24.9%(P&lt;0.05) at 1 h after administration, respectively, while other fractions were not active. Thirty-three and twelve compounds were identified from n-butanol and water fraction by LC-MS/MS analysis, respectively, including ten tannins, fifteen anthraquinone glycosides, four anthrone glycosides, one phenolic glycoside, one naphthaline derivative, one anthraquinone and one sucrose. These results revealed that rhubarb had antipyretic activity on rats, and tannin and anthraquinone glycosides were the main active ingredients inside.

Objective: To compare the photosynthetic characteristics and medicinal ingredients in different months in order to provide a theoretical basis for cultivation and harvest of Inula nervosa., Methods: The photosynthetic characteristics was measured by using LI-6400 and morphological characteristics were compared in different months, and the contents of total flavonoids and total phenols were determined by UV spectrophotometry., Results: Net photosynthetic rate of Inula nervosa was the highest in June, which showed a single peak curve, and the average of daily change reached to 8.50 μmol/(m2 x s). Light response curve data showed the ability of using the strongest light was in June. Chlorophyll fluorescence parameters values also displayed that, openness of reflect center and photochemical efficiency of leaves' photosystem II were the highest, which also had the fastest rate of electron transfer in June. Morphological indicators showed that the single leaf area and leaf area of Inula nervosa were significantly higher in June than those in other months. The content of total phenols were much higher than that of total flavonoids in Inula nervosa. And the medicinal ingredient content of the underground part was higher than that in the aerial part., Conclusion: The best harvest time of underground part of Inula nervosa should be after autumn, when the weight and active ingredients are accumulated to a considerable level.