To screen water-saving varieties and provide management guidance for variety production and planting, promotion varieties in the Huanghuai region were selected to analyze the changes in plant height and stem structure, yield composition, and water use efficiency (WUE) of different varieties under three modes: only base fertilizer (W0), base fertilizer+water at jointing stage (W1), and base fertilizer+water at jointing stage and grouting stage (W2). The results showed that: (1) compared to W0, the plant height, stem length under spike, the length of penultimate internode and the 3rd internode from top increased significantly under W1 treatment, with the largest increase in the stem length under spike, and the basal internode changes were not significant; compared to W1, there was an increase in plant height under W2 treatment, but the increase of each internode was not significant; compared to W0, the plant height of 'Zhoumai 18' and 'Luomai 28' increased significantly under W2, with increase of 36.49% and 35.30% respectively; under W1 and W2 treatments, the basal internode length of 'Zhengmai 129' was the largest, and attention should be paid to fertilizer and water management to prevent lodging during production and utilization; (2) compared to W0, under W1 treatment, ear number per plant and the number of grains per panicle increased significantly, and the thousand grain weight decreased significantly, resulting in a significant increase in yield; compared to W1, W2 treatment showed a significant increase in thousand grain weight and yield, while other differences were not significant; (3) compared to W0, WUE of varieties under W1 treatment increased significantly, and 'Fengdecun 12' and 'Luomai 28' had the highest WUE; compared to W1, WUE of varieties under W2 treatment was significantly lower than that under W1 treatment, with 'Fengdecun 12' and 'Luomai 28' still had the highest WUE.
Maize varieties ‘Zhengdan 958’, ‘Jidan 50’, ‘Limin 33’, and ‘Xianyu 335’ were used as experimental materials to study the effects of low-temperature processes and low soil moisture on maize germination. Tests of low temperature and low soil moisture stresses on germination of 4 maize varieties were carried out in the phytotron combined with the regulation of soil relative humidity. The results showed that compared with the suitable temperature condition, the period from sowing to germination of the four varieties were prolonged by 3-9 days when the average temperature was below 10°C for more than 5 days and the relative humidity of the dry soil was between 50%-60%. The experimental data showed that the adverse effect of low temperature on germination and reaching 100% germination rate of maize was stronger than that of low soil moisture. The combined effect of low-temperature processes and low soil moisture on maize germination was more serious than the single effect of low temperature and low soil moisture. The effects of low temperature and low soil moisture on different maize varieties were different. The low temperature resistance was in the order of ‘Xianyu 335’>‘Zhengdan 958’>‘Limin 33’>‘Jidan 50’ while the drought resistance was in the order of ‘Xianyu 335’>‘Zhengdan 958’ and ‘Limin 33’>‘Jidan 50’. The low-temperature and drought resistance was in the order of ‘Zhengdan 958’>‘Xianyu 335’>‘Limin 33’>‘Jidan 50’.
Anoectochilus roxburghii is a rare and precious medicinal and ornamental plant of the Orchidaceae. It is favored by people for the rich variety of medicinal and nutritional components, and its market demand has been increasing in recent years. In order to promote the industrial development and basic research of A. roxburghii, this paper summarizes previous studies on A. roxburghii research, briefly compares the phylogenetic differences of Anoectochilus, focus on the research results of genomics (structural genomics/functional genomics) and adversity (biotic/abiotic interaction) response, analyzes the main factors affecting the quality of A. roxburghii (processing methods, cultivation models, strains). This paper systematically reviews the studies on germplasm resources, genomics, environmental interaction, quality difference and embryo reproduction that have not been carried out in depth, and puts forward corresponding strategies and prospects for the main problems and the solutions. It provides a feasible reference for the molecular biology research of precious medicinal plants in the era of big data.
This paper investigates the fungal community diversity of Pinus sylvestris var. Mongolica needles under different degrees of disease, which can provide valuable information for the identification and control of foliar diseases. The needles of Pinus sylvestris var. mongolica were sampled, and the collected samples were analyzed for fungal community diversity by high-throughput sequencing technology. The fungi with high relative abundance were compared by BLAST, and phylogenetic trees were constructed and analyzed. The relative abundance of species in the nine conifer samples was mainly distributed among Ascomycota and Basidiomycota, and a minimal amount of Rozellomycota fungi were also present in the conifer. The Ascomycota was the dominant phylum with the largest relative abundance at the "phylum" level. The Mycosphaerellaceae accounted for 92%, 92%, and 29% of the heavy disease samples W3-3, T78-3, and T87-3 from three different forestry sites, respectively. It was found that there were some differences in the community composition structure of different forest sites, and different levels of incidence caused different evenness of species composition, indicating that the relative abundance of fungi after incidence was influenced by both the level of incidence and the geographical environment. The percentage of Dothistroma septosporum increased as the degree of incidence increased. A phylogenetic tree was constructed based on the ITS sequences of the pathogenic fungus, and the pathogenic fungus causing the Dothistroma pini Hulbary in the foliar parts of camphor pine in the three forest sites was confirmed to be D. septosporum.
To improve the fertilizer utilization rate and increase the rice yield, the experiment investigated the effect of different types of slow release fertilizers on hybrid rice ‘Yongyou 12’. The results showed that ‘Hanfeng’ slow release fertilizer had a significant effect on yield increase, which was 2.7%-3.5% higher than that of the formula fertilizer. ‘Liuguowang’ slow release fertilizer and ‘Fengzhu’ slow release fertilizer had no significant yield increase effect. The spike rate and the number of grains per spike under ‘Hanfeng’ slow release fertilizer were higher than that of others, which compensated the lower effective spike number. The leaf area index and dry matter under ‘Hanfeng’ slow release fertilizer were the highest in growth. Based on the performance of yield and population characteristics, ‘Hanfeng’ slow release fertilizer was better than that of ‘Liuguowang’ and ‘Fengzhu’. It could provide a basis for seed-specific fertilization of ‘Yongyou 12’.
Ganoderma lucidum is an excellent traditional Chinese medicine, with a huge market demand in Asia and other regions. And the traditional intensive cultivation always results in low yield and poor quality of ganoderma lucidum. Water-dry rotation has been proved to be a practical, effective and sustainable agricultural measure, but study on ganoderma lucidum-rice rotation is extremely rare. To explore soil microbial communities’ succession at different stages of ganoderma lucidum-rice rotation, high-throughput sequencing was used to analyze soil bacteria and fungal communities structure at different stages of DAF, L1 and L2. The results showed that from DAF to L2, the diversity index values of bacteria gradually decreased, and that of fungi decreased and then increased. The ganoderma lucidum-rice rotation had a significant impact on the structure of bacterial and fungal communities. The relative abundance of rhodobacter and gemmatimonas at DAF was significantly higher than that at L1 and L2. And abundance of MND1, escherichia coli-Shigella, Dongia, streptomyces and Ellin6067 were the opposite. As for fungi, the relative abundance of psathyrella at L1 was significantly higher than that at DAF and L2, while mortierella was the opposite. The correlation analysis showed that most of the soil chemical nutrient indicators were significantly negatively correlated with the fungal diversity indicators, but not with the bacterial richness, bacterial diversity and fungal richness. RDA analysis showed that SOM was the main environmental factor affecting the bacterial community, while AP and AK were the main factors affecting the fungal community. Ganoderma lucidum-rice rotation is beneficial to improve the soil microbial community structure, increase the yield and quality of ganoderma lucidum. Thus, it has a significant positive effect on the sustainable agricultural production of ganoderma lucidum.
The experiments of straw composting and returning to the field were carried out according to the cold climate characteristics of autumn and winter in the Northeast region and the practical operational requirements. Field composting experiments were conducted after the harvest of corn in autumn, and the environmental temperature, precipitation, straw pile temperature and straw weight loss rate were continuously monitored. The fully decomposed corn straw was used as fertilizer and applied to the field for three consecutive years. The soil organic matter, available nitrogen, available phosphorus, available potassium, soil porosity and bulk density were monitored as indicators. A 2-year application experiment was carried out in basic farmland and shed protected areas. The results showed that the weight loss rate of 120 d straw reached 31.53%. By using rotten straw for three years, the soil organic matter increased by 4.06-6.31 g/kg, the alkaline hydrolyzable nitrogen in soil increased by 15.08-27.35 mg/kg, the available phosphorus increased by 18.11-21.95 mg/kg, quick-acting potassium increased by 63.97-89.93 mg/kg. The soil bulk density was reduced by 0.10-0.14 g/cm3. The water holding capacity of soil in the field increased by 7.51%-9.24% (V/V). The soil porosity increased by 3.69%-5.27% (V/V) (P≤0.05). In the application experiment in basic farmland and protected areas, there was a slight increase in available nutrients and organic matter, while bulk density and field water holding capacity had a significant change. The application of decomposed straw could reduce soil bulk density, increase soil porosity and field water holding capacity and improve soil compaction issues. Decomposed straw played a significant role in improving and conserving the properties of black soil.
In this study, the effects of two new fertilizers and their matching application methods on soybean density and soil enzyme activity were researched. ‘ZLD 120’ was used as the experimental material, the split-plot trial was performed with 6 fertilization treatments (blank fertilization, normal fertilization, low concentration ammonium thiosulfate, high concentration ammonium thiosulfate, 0.5 normal fertilizer+Master Copper, 0.3 normal fertilizer+Master Copper, respectively recorded as T1, T2, T3, T4, T5, T6) as main zones and 3 planting density levels (15×104 plants/ hm2, 20×104 plants/ hm2 and 25×104 plants/ hm2) as sub zones. The results showed that under the same fertilization treatment, the soybean yield increased firstly and then decreased with the increase of planting density, and reached the maximum at M2. With the increase of planting density, the main stem diameter and chlorophyll content gradually decreased, and the plant height and leaf area index gradually increased. Under the same planting density, the yield, leaf area index, soil alkaline phosphatase and sucrase activity increased, but the plant height, main stem diameter and soil urease activity of soybean reduced in ammonium thiosulfate treatment. Compared with T1 and T2, the chlorophyll content was higher in T3. The chlorophyll content increased in T1 compared with T4. Soybean yield under the Copper Master treatment was significant higher in T4 and T5 than that in T1 and T2 under M3 density, but the overall yield was low compared with other densities at this time. The plant height, main stem diameter, leaf area index and soil enzyme activity trend of soybean under Copper Master treatment were lower than that of T1 and T2 on the whole, but the chlorophyll content showed contrary result. To sum up, ammonium thiosulfate treatment under 20× 104 plants/ hm2 was the best cultivation pattern, and the maximum yield was 3200.00 kg/ hm2 under M2T4. We should explore the application of Copper Master on soybeans for the future research.
The study aims to explore the spatio-temporal variation of available zinc content in tobacco-growing soil in Kunming, so as to provide scientific basis and guidance for preventing and controlling soil zinc pollution in high quality tobacco-growing areas and improving plough land quality. By GPS positioning, a total of 3347 soil samples were collected from the plough layer (0-20 cm) of core area in eight tobacco-growing counties of Kunming in 2018-2020, respectively. Based on them, we analyzed the temporal and spatial variation characteristic of soil zinc. The main driving factors of soil Zn were analyzed by using regression and boosted regression tree model. The results showed that the soil available zinc was 2.53 mg/kg, and the coefficient of variation of Zn was 89.55%, and Zn variation was high in 2020. In addition, the proportion of abundant and high grade was larger (75.83%), which was at the high and enrich level. Compared with 2019, soil Zn was relatively stable, but its mean value decreased by 0.85 mg/kg than that of 2018, and its variation increased. The distribution frequency of soil Zn in rich and extremely grades decreased by 15.01%, while the proportion of suitable level sites increased by 8.34%. In 2020, the mean Zn range of the eight counties was 1.84-4.19 mg/kg, and the coefficient of variation was 55.22%-93.37%. Meantime, the variation of Zn mean value was as followed: Xundian>Anning>Songming>Fumin>Luquan, Jinning>Yiliang>Shilin. Compared with 2019, the soil Zn content in Fumin, Lujian, Songming and Xundian decreased by 0.11-0.69 mg/kg in 2020, while them in Anning, Jining, Yiliang and Shilin were relatively stable. The soil Zn content in 2020 decreased by 0.23-1.65 mg/kg than that of 2018, and among which Fumin, Songming and Xundian decreased the most. In 2020, the amount of Zn in the rich and extremely levels decreased by 0.16%-15.03% and 5.88%-23.20% compared with that in 2019 and 2018, respectively. The decrease rate was highest in Yiliang and lowest in Songming. The Pearson’s correlation, regression fitting and boosted regression tree model revealed that the most main factor causing spatial scale difference of Zn was average annual precipitation, followed by average annual temperature, evaporation, soil type, soil texture. Meantime, the soil pH value and hydrolyze nitrogen, organic matter, available potassium and phosphorus contents were selected as driving factors. Moreover, the long-term inputs of nitrogen, potassium, phosphate fertilizer also played key roles in soil Zn change. Overall, the Zn content of tobacco-growing soil was generally high, but showed a decreasing trend in recent 2 years. In the future, we should continue to reduce nitrogen, and control the application of phosphorus, potassium, organic fertilizer containing Zn and chemical fertilizer to reduce Zn input. Furthermore, the soil pH value and acidification should be considered to ameliorate zinc form and reduce the risk of high Zn concentration in tobacco and soil pollution.
In the comprehensive remediation project of Xitailong River basin in Shatian Town of Dongguan City, Guangdong Province, in order to solve the problem of post-treatment of dredged contaminated substrate, the basic characteristics of the substrate in the upper reaches of Xitailong River, the middle and lower reaches of the river confluence and the lower reaches of the river were investigated, and the feasibility of upgrading it to green planting soil was analysed. The results showed that the pH of Xitailong River substrate ranged from pH 6.45 to 7.35, the infiltration rate ranged from 2.17×10-4 to 8.9×10-4 cm/s, and the soil texture was powdery loam, all of which met the CJ/T 340-2016 industry standard for urban construction. The nutrient content of the river sediment is sufficient, but the spatial heterogeneity is large, with the nutrient content of the substrate much higher in the downstream than in the upstream reaches. The area near the downstream river is affected by the surrounding factories and the heavy metal elements in the substrate are high, with serious exceedances of the elements Ni and Cu, which does not meet the minimum standards for heavy metal content in plantation soils. A thorough analysis shows that the characteristics of the upstream river substrate is more in line with the CJ/T 340-2016 standard, which can be used as green planting soil through improvement, and is of great importance for the environmental management of urban water bodies.
A field monitoring experiment was conducted to study the effects of non-fertilization (T1), traditional fertilization (T2) and slow-release fertilization (T3) on nitrogen and phosphorus runoff loss during maize growing season in the upper reaches of the Beiyun River watershed. The results showed that when the rainfall exceeded 30 mm in 12 hours, the soil water content was saturated, and the surface runoff was produced, and if the rainfall exceeded 30 mm in 1 hour, the runoff would be intensified. Compared with T2 treatment, T3 treatment had lower TN, TP, ammonium N and nitrate N loss by 15.3%, 24.2%, 10% and 12%, respectively, but there was no significant difference. The TN loss rate of T3 treatment was 0.07%, which was 46.2% less than that of T2 treatment, the TP loss rate of T3 treatment was 0.13%, which was 71.7% less than that of T2 treatment, and the nitrate N loss rate of T3 treatment was 0.06%, which was 25% less than that of T2 treatment. In conclusion, compared with traditional fertilization, the application of slow-release fertilizer could reduce the loss of nitrogen and phosphorus, which provided data support for scientific promotion of slow-release fertilizer and evaluation of the effect of slow-release fertilizer on the loss of nitrogen and phosphorus.
The purpose of this study is to provide scientific reference for the quarantine detection, comprehensive control and risk analysis of Bactrocera dorsalis Hendel in Sichuan Basin. Four niche prediction models, i.e. Maxent, GARP, Bioclim and Domain were used to predict the areas of potential distribution of B. dorsalis in Sichuan Basin. The results of different models were analyzed and compared using two statistical criteria: the area under the receiver operating characteristic curve (AUC) and Kappa value. The AUC average values of the four models are all above 0.9 and the Kappa average values are above 0.75, indicating that the prediction model has high prediction accuracy. Furthermore, the paper shows that precipitation of the driest month, mean temperature of the wettest quarter, temperature seasonality and mean diurnal range are the key environmental variables that dominated the potential distribution of B. dorsalis, which play a decisive role in the formation of the current distribution of B. dorsalis. The suitable areas and locations of B. dorsalis predicted by four models are quite different, but they all contain the hilly area in central Sichuan Basin, the parallel rank-valley area in eastern Sichuan Basin and the low mountain area in southern Sichuan Basin. The highly and moderately suitable areas are concentrated in the east of the hilly area in central Sichuan Basin, the west of the parallel rank-valley area in eastern Sichuan Basin and the low mountain area in southern Sichuan Basin. It can be seen that the suitable areas of B. dorsalis in Sichuan Basin is wide. In view of the economic importance of citrus to Sichuan Basin, the local relevant departments should strengthen the detection and quarantine work of B. dorsalis to avoid large losses.
Bacillus thuringiensis (Bt) is the most successful microbial insecticide in application. The largest class of insecticidal proteins produced by Bt is Cry toxin, and its application in field is an important means for controlling agricultural pests and increasing crop yields. Cry toxin has the advantages of quick-acting at host organisms, low impact on non-target organisms, environmental friendliness and degradability. This study briefly describes the research on insect resistance caused by Cry toxin when it is put into agricultural use. The research status of structure and function, mechanism of action, protein domain and insect resistance of Cry toxin are summarized. The three main features of the promotion of insect resistance by epigenetic mechanism, receptor regulation and native intestinal flora are concluded. The Countermeasures against resistant insects are analyzed. It is considered that artificial selection of new resistant insects can predict possible resistance pathways, and directional evolution of Cry toxin and interactive use strategy in field are the research priorities. The paper is aimed to provide theoretical basis for successful application of Cry toxin in agricultural biological control.
In order to identify the pathogenic fungi that caused maize melasma in Zhangye, Gansu Province, specimens with typical disease symptoms were collected in Zhangye City in September 2021,, tissue separation was used for isolation and purification, and the pathogenicity was verified by Koch's rule. Identification was performed by using morphological characteristics and molecular biology methods. The results showed that 39 isolates were obtained from diseased samples, of which 30 isolates caused disease symptoms similar to those observed in the field, the symptoms were rhizome rot, root rot and stem rot. According to the morphological characteristics, all 30 pathogens were identified as Fusariumspp. Fungi. Combined with molecular biology methods, 30 pathogenic Fusarium fungi were identified as Fusarium verticillioides, F. oxysporum, F. proliferatum, F. solani, F. incarnatum and F. flocciferum, with the isolation frequencies of 50.00%、20.00%、16.67%、6.67%、3.33% and 3.33%, respectively. Among them, F. verticillioidesis was the dominant pathogen of maize melasma in Zhangye City, and F. flocciferum was first reported to infect maize. The results of this study provide a basis for the diagnosis and prevention of maize melasma.
In order to clarify the predation ability and predation regularity of Megalocaria dilatata on bean aphid, the M. dilatata collected in the wild was raised indoors for 2 generations, and then predation of each instar larva, female and male adult was measured. The Holling II disk equation was fitted by the reciprocal method, and the predation characteristics of the M. dilatata were determined. The results showed that the predation amount of M. dilatata increased with the age of M. dilatata. When N→∞, the maximum predation of the 1st to 4th instars larvae, female and male adults on the bean aphid within 1 day were 30.1628, 158.7003, 556.3928, 988.1128, 841.0084 and 589.4011, respectively. The fitting equation between the predation amount and day age was y=3.9123x2.2092(R2=0.8093), and the predation amount increased exponentially with the increase of day age. The fitting equations of predation and day age of female and male adults were y=0.9453x2-28.274x+827.44(R2=0.456) and y=0.8762x2-31.511x+635.38 (R2=0.7188), respectively, and predation amount of female and male adults decreased gradually with the increase of day age.
To better understand the current research status of Spodoptera litura, taking the relevant literatures of Spodoptera litura collected in CNKI (China National Knowledge Infrastructure) database and WOS (Web of Science) database as the object, the CiteSpace bibliometric method was used to compare and analyze, and visual charts were drawn from three aspects of author, organization and keywords, respectively, to summarize the evolution trend and research hotspots of Spodoptera litura. The research shows that the control of Spodoptera litura has been the main research at home and abroad. In recent years, China's research on Spodoptera litura has mainly focused on the unreasonable application of chemical pesticides in the control process, which leads to soil and environmental damage and induces the evolution of resistance mechanisms in Spodoptera litura. Under the background of advocating pollution-free, green and organic, the control measures of Spodoptera litura tend to biological control, while foreign research focuses on its internal structure and viral pesticides. To sum up, the current research on Spodoptera litura is mainly divided into two parts. One is the combination of biological and chemical control to develop efficient and low pollution control methods or pesticides. The other is the research on the growth, development and internal structure of Spodoptera litura, reducing the population number of certain pests and reducing the harm without destroying biodiversity.
The aim of this study was to select an ideal alfalfa variety that could overwinter in Heilongjiang Province. Three cold-resistant mutants, lm1609, lm1625 and lm1704, were obtained from the second-generation population of ‘Longmu 806’ after magnetic field free space treatment, and their cold-resistant performance was identified by measuring germination index, wintering rate, yield characteristic index and root physiological and biochemical index. There was no significant difference in germination index between the three mutants and the control. The germination potential and simplified activity index of lm1609 were significantly higher than those of lm1625 and lm1704 (82.05% and 469.82, respectively) (P<0.05). The overwintering rate of the three mutants was significantly lower than that of the control group. There was no significant difference in plant height between mutants and control on June 6. With plant growth, lm1609 and lm1704 on July 6 and August 6 were significantly higher than those of lm1625 and control. The difference in fresh grass yield among the mutants lm1609, lm1625 and lm1704 was not significant, but significantly higher than that of the control (P<0.05). The root peroxidase and superoxide dismutase of the three alfalfa mutants were significantly higher than those of the control, and the highest POD and SOD of the mutants were 304.85 OD470/(min·g) and 208.41 U/g, respectively (P<0.05). lm1609 mutant was an ideal cold resistant mutant material that has high cold resistance and yield characteristics.
The study aimed at establishing a high performance liquid chromatography (HPLC) method for the determination of pyraclostrobin and kresoxim-methyl in three different types of soil from Xinjiang, Inner Mongolia and Heilongjiang. The separation of pyraclostrobin or kresoxim-methyl in samples was performed by modified QuEChERS method combined with HPLC, and the quantitative results were calculated by external standard method. The results showed good linearity in the concentration ranged from 0.3-10.0 mg/L, and the correlation coefficient (R2) was greater than 0.9999. At different concentrations, the average recoveries of pyraclostrobin and kresoxim-methyl in Yermosols of Xinjiang were 98.03%-102.32% and 100.33%-107.18% with relative standard deviations (RSD) of 0.46%-0.87% and 0.94%-1.67%. The average recoveries of pyraclostrobin and kresoxim-methyl in Chernozem of Heilongjiang were 100.40%-104.32% and 90.83%-101.33% with RSD of 0.47%-2.78% and 1.35%-1.69%. The average recoveries of pyraclostrobin and kresoxim-methyl in Xerosols of Inner Mongolia were 100.04%-107.40% and 96.90%-98.86% with RSD of 0.77%-1.41% and 1.08%-1.57%. The accuracy and precision of the method meet the requirements of pesticide residue analysis, and it is suitable for the determination of pyraclostrobin and kresoxim-methyl in above types of soil.
To establish the efficient determination of pumpkin starch components, which would be of great significance for directional breeding of special pumpkin starch varieties and rational development, the experiments were carried out. According to the dual-wavelength colorimetric principle, the determination wavelength and reference wavelength of pumpkin starch components were determined by using the purified pumpkin amylose and amylopectin and the equal absorption point diagram. The 200 μL reaction system for the determination of pumpkin starch components with dual wavelengths was determined by single factor comparison test. Finally, the content of starch components in different types of pumpkin was compared. The extreme materials were screened. The results showed that the determination wavelength of pumpkin amylose was 616 nm, the reference wavelength was 472 nm, and the determination wavelength of pumpkin amylopectin was 545 nm and the reference wavelength was 725 nm. The regression equations of pumpkin amylose and amylopectin were established. The linear relationship was good (R2>0.9900) when the amylose concentration was in the range of 0.0125-1 mg/mL, and the amylopectin concentration was in the range of 0.025-2 mg/mL. The 200 μL reaction system in a 96-well plate consisted of 20 μL of sample, 90 μL of acetate buffered saline (pH 3.5), and 90 μL of 12-fold iodine diluent. The tested 23 pumpkin materials had amylose content of 0.52-26.68 mg/g fresh flesh weight, amylopectin content of 0.03-76.13 mg/g fresh flesh weight and total starch content of 0.55-101.61 mg/g fresh flesh weight. The fresh flesh weight of 10 and 15 mg/g, the fresh flesh weight of 35 and 45 mg/g, and the fresh flesh weight of 55 and 65 mg/g could preliminarily evaluate the low, medium and high contents of amylose, amylopectin and total starch in tested pumpkin, respectively. The content of starch components of the inbred lines derived from inter-specific hybrids of Cucurbita moschata Duch. × Cucurbita maximam Duch. were higher than that of the tested C. moschata and C. maximam. Finally, seven inbred lines of C. moschata × C. maximam were screened out, which would show great potential for directional breeding of special pumpkin starch varieties. The efficient detection system for starch components in pumpkin would improve the efficiency of pumpkin starch breeding.
To comprehensively understand the current status and development trend of quinoa research at home and abroad in the past decade, this paper used bibliometric methods to comprehensively study the relevant literature on quinoa research, which were retrieved from the China National Knowledge Infrastructure (CNKI) Chinese Journal Full-text Database and Web of Science (WOS) Core Collection Database from 2012 to 2022. The year of publication, research institutions, journal distribution, and subject field distribution of the literature were statistically analyzed, and the main research frontiers and hotspots of quinoa at home and abroad were summarized by keyword co-occurrence network analysis. The results show that quinoa research has been growing rapidly since 2013, “The International Year of Quinoa”, and has been in a period of rapid growth in the past three years. Although the research on quinoa started late in China, the number of published papers has surpassed that of the European and American countries, ranking first in the world. However, the paper quality needs to be further improved, and the average citation frequency is ranked after Germany, Italy, Chile, the United States and Spain. Foreign research institutions are mainly distributed in the origin area of quinoa in South America and developed countries in Europe and North America, while domestic research institutions are mainly concentrated in the quinoa planting areas such as Northwest China and North China. The distribution of journals is mainly in the field of food science, and the research hotspots are mainly focused on breeding and cultivation, nutritional quality, and processing characteristics. As a kind of healthy grain, quinoa is emerging in China, and promoting its industrialization has broad development prospects and application space.
In order to evaluate the carbon sink capacity of mariculture shellfish in Guangdong Province, based on the output of mariculture shellfish in Guangdong Province in the China Fishery Statistical Yearbook, the quality and value of the carbon sink capacity of mariculture shellfish in Guangdong Province from 2016 to 2020 were evaluated with reference to tissue dry mass ratio and tissue carbon content. The results showed that the carbon sink capacity of mariculture shellfish in Guangdong Province was stable on the whole. The removal of carbon material by shellfish was 156300 tons per year, equivalent to the removal of 573500 tons of CO2, and the annual economic value was 86-343 million US dollars. The study shows that the environmental benefits and considerable economic benefits brought by shellfish carbon sink in Guangdong Province are helpful to accelerate the realization of the "double carbon" goal in our country, and we should pay more attention to the treatment of shells at the same time.
To investigate the anesthetic effect of eugenol on junvenile Schizothorax chongi and provide theoretical basis for artificial breeding of Schizothorax chongi, we measured the time of anesthesia and recovery under different concentration, different anesthetic time and different exposure time by hydrostatic method. The results showed that a negative correlation between the eugenol concentration and anesthesia time was identified with y1=286.63e-0.0135x, R2=0.9593; a positive correlation between the eugenol concentration and recovery time was found with y2=101.54e0.0134x, R2=0.9913; the anesthetic time and the recovery time differed significantly with different concentration of eugenol (P<0.05); the recovery time was positively correlated with the anesthetic time (y=64.647x0.2394, R2=0.9823) under concentration of eugenol was 40 mg/L; a significant negative correlation between recovery time and exposure time was identified with y=900.92x-0.4078, R2=0.8961. The conclusion of this study was that eugenol concentration of 40-80 mg/L was the best in the production, transportation and sampling; the medicinal bath time of young fish should not exceed 600 s and the exposure time of juveniles were permitted no more than 1200 s.