Journal of Shenyang Agricultural University

Effects of Exogenous Melatonin on Growth and Physiological Characteristics of Chamerion angustifolium Seedlings under Salt Stress

[Objective]Soil salinization is one of the major abiotic stress factors limiting the growth and development of landscape plants worldwide. Melatonin(MT), an indoleamine regulator widely presents in living organisms, has shown considerable potential for alleviating damage caused by drought, salinity, and extreme temperatures by enhancing intracellular antioxidant defense, scavenging excess reactive oxygen species, and maintaining ionic homeostasis. This study aimed to investigate the regulatory mechanisms of exogenous MT on the growth, development, and physiological homeostasis of Chamerion angustifolium seedlings under salt stress.[Methods]Wild Chamerion angustifolium seedlings from Xilingol(provenance A) and Hulunbuir(provenance B) were used in a pot experiment. Two NaCl concentrations(0 and 150 mmol·L^-1) and three foliar MT concentrations(0, 100, and 200 μmol·L^-1) were applied to evaluate the effects of MT on seedling phenotypic and physiological traits. [Results]Exposure to 150 mmol·L^-1NaCl significantly inhibited the growth and photosynthetic carbon fixation efficiency of Chamerion angustifolium seedlings. Foliar application of 200 μmol·L^-1MT significantly alleviated salt-induced damage, and growth inhibition was mitigated in seedlings of both provenances. Exogenous MT enhanced enzymatic antioxidant defense in seedlings of both provenances by increasing the activities of superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), glutathione reductase(GR), ascorbate peroxidase(APX), and glutathione peroxidase(GPX), while reducing the accumulation of malondialdehyde(MDA) and total reactive oxygen species(T-ROS),thereby mitigating salt-induced oxidative damage. In addition, MT increased the activities of ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco) and Rubisco activase(RCA), thereby promoting the recovery of photosynthetic carbon metabolism in Chamerion angustifolium seedlings under salt stress. [Conclusion]Exogenous MT significantly improved the salt tolerance of Chamerion angustifolium seedlings by alleviating salt-induced growth inhibition, improving photosynthetic carbon metabolism, and strengthening antioxidant defense capacity.

Functional Analysis of OsAlR2 in Regulating Aluminum Tolerance in Rice

[Objective]Study was carried out to investigate the function of the aluminum tolerance-related gene OsAlR2 under aluminum stress, and to elucidate the regulatory mechanism by which OsAlR2 participates in regulating aluminum stress responses.[Methods]In our previous study, an aluminum tolerance-related gene OsAlR2 was identified. The knockout mutant ko-alr2 and overexpression mutant oe-alr2 were generated, and the phenotypes and physiological mechanisms of these lines were analyzed.[Results]After aluminum treatment, the root length and root activity of oe-alr2 were lower than those of the wild type, whereas no significant differences were observed between ko-alr2 and the wild type. In terms of aluminum content, the Al³⁺ content in ko-alr2 was significantly lower than that in the wild type, while no obvious difference was found in oe-alr2 compared with the wild type.Subsequent section observation showed that root cells of oe-alr2 exhibited varying degrees of damage after aluminum treatment,whereas no obvious damage was detected in the wild type and ko-alr2. Under aluminum stress, the MDA content in oe-alr2 was significantly higher than that in the wild type, while the MDA content in ko-alr2 was markedly lower. Assays of the reactive oxygen species-scavenging enzymes CAT and SOD revealed that the activities of CAT and SOD in ko-alr2 were significantly higher than those in the wild type, whereas the activities in oe-alr2 were lower. The expression levels of several known aluminum tolerance genes,including OsFRDL2, OsSTAR1, and OsCDT3, were determined. Under aluminum stress, the transcript levels of OsSTAR1 and OsCDT3 in ko-alr2 were significantly upregulated and higher than those in the wild type, while the opposite pattern was observed in oe-alr2.[Conclusion]These results demonstrate that the OsAlR2 gene is involved in regulating the defense of rice against aluminum toxicity. It negatively regulates aluminum tolerance in rice by modulating reactive oxygen species-scavenging capacity and the expression of aluminum tolerance-related genes. This study lays a foundation for further revealing the regulatory mechanism of this gene in response to aluminum stress at the rice seedling stage.

Exploring Selective Domestication and Germplasm Evolutionary Patterns of Candidate Genes Related to Maize Grain Moisture Content

[Objective]Identifying key genes regulating maize seed moisture content and clarifying their evolutionary patterns in breeding materials from different eras is of great significance for the breeding of maize varieties suitable for mechanized harvesting.[Methods]In this study, 297 candidate genes associated with grain moisture content in maize were collected. The GO enrichment analysis was performed to elucidate the biological processes in which these genes are involved. Evolutionary analysis of the promoter regions of candidate genes was conducted using maize wild relatives, landraces, and American inbred lines to assess their selection signatures during domestication. Meanwhile, the allele frequency dynamics of candidate genes during genetic improvement were analyzed using Chinese maize germplasm from different breeding eras. Key genes subjected to both domestication selection and genetic improvement selection were identified through intersection analysis. Subsequently, the differences in grain moisture content among different genotypes of the key genes were analyzed, along with the frequency changes of target alleles during the breeding process.[Results]The GO enrichment analysis revealed that the 297 candidate genes were significantly enriched in biological processes such as cell wall organization and oxidation-reduction reactions, suggesting that these processes may be involved in regulating seed moisture-related traits. The evolutionary analysis indicated that the promoter regions of candidate genes were under selection during domestication, and some genes were also selected during the genetic improvement process of Chinese maize germplasm across different breeding eras. Through intersection analysis, seven key genes subjected to both domestication selection and genetic improvement selection were identified. Among them, three genes showed significant differences in grain moisture content among different genotypes; in addition, the allele frequency associated with higher grain moisture content of other two genes exhibited a continuous decreasing trend during genetic improvement.[Conclusion]This study provides theoretical support for elucidating the germplasm evolution pattern of grain moisture content in maize and offers important candidate gene resources for breeding machineharvestable maize varieties.

Adaptability and High-yield Characteristics of 13 Soybean Varieties from Heilongjiang in the Northern Xinjiang Region

[Objective]Study was carried out to screen out high-yielding double-cropping soybean varieties suitable for cultivation in Northern Xinjiang and clarify their high-yield growth characteristics.[Methods]This experiment was conducted in 2023 and 2024,using 13 double-cropping soybean varieties as test materials. The differences in growth period, agronomic traits, flower and pod parameters, and yield among different varieties were compared in the field.[Results]The results showed that the growth period of the tested varieties ranged from 87 to 102 days, all of which could mature normally. There were significant differences in yield among different varieties(lines) in different years, with yields ranging from 2 235.6 to 3 226.02 kg·hm^-2. The yields of HN151 and JD30 were the highest in both years. In 2023 and 2024, the plant heights of soybeans were 42.6 to 86.58 cm and 53.0 to 72.8 cm,respectively; the bottom pod heights were 6.37 to 17.2 cm and 7.56 to 14.0 cm, respectively; the stem diameters were 3.21 to 5.54 mm and 2.28 to 4.96 mm, respectively; the effective pod numbers per plant were 9.82 to 27.2 and 9.6 to 22.4, respectively; the seed numbers per plant were 25.4 to 86.0 and 21.4 to 52.4, respectively; and the 100-seed weights were 16.2 to 20.96 g and 15.62 to 20.82 g, respectively.[Conclusion]Comprehensive analysis indicated that HN151 is suitable for large-scale cultivation in Northern Xinjiang, with a yield over 3 000 kg·hm^-2. A higher number of flowers, pods, and seeds per unit area is the key to achieving high yields of soybeans in Northern Xinjiang.

Effects of Different Lily Cultivars on the Development and Reproduction of Cotton Aphid, Aphis gossypii Glover

[Objective]Study was carried out to clarify the adaptability of Aphis gossypii Glover on different lily varieties, and to achieve an eco-friendly and efficient biological control strategy by leveraging the intrinsic aphid resistance of lilies to manage aphid damage. [Method]Under laboratory conditions, the development and reproduction of cotton aphid on five lily varieties(Fangio, ConcaD'or,Sorbonne, Tarisa, and Viviana) were observed using biological methods, and experimental population life table was constructed.[Results]Different lily varieties significantly affected the development and reproduction of A. gossypii. The survival rate of cotton aphid was lowest on Tarisa. On Fangio, the adult longevity(5.32 d) and total lifespan(9.56 d) were the shortest, and fecundity(23.59 offspring) was the weakest, all significantly lower than those on other varieties. On Viviana, the adult longevity(11.75 d) and total lifespan(16.01 d) were the longest, and fecundity(50.24 offspring) was the highest, significantly exceeding those on other varieties.Population life table parameters showed that the intrinsic rate of increase(r=0.312), finite rate of increase(λ =1.366), and net reproductive rate(R₀=36.84) of A. gossypii on Viviana were significantly higher than those on other varieties, while the parameter values on Fangio and Tarisa were the lowest. [Conclusion]Based on various indicators, Viviana is a suitable host variety for the population growth of A. gossypii, whereas Fangio and Tarisa are unsuitable. The research results provide a theoretical basis for the forecasting and management of A. gossypii and the breeding of aphid-resistant lily varieties in lily production.

SD-SSPs Simulation and Path Study on Coordinated Multi-system Development of Resource-Based Cities in the Yellow River "Jizi Bend"

[Objective]Resource-based cities are confronting the challenges of achieving high-quality development. Clarifying the coordinated development pathways of the "Resource-Environment-Society-Technology" complex system can reveal the interaction mechanisms among multidimensional factors， thereby providing optimal strategies for the sustainable development of resource-based cities in the Yellow River "Jizi bend" region. [Methods]This study focuses on 18 spatially clustered resource-based cities in the Yellow River "Jizi bend" region. A system dynamics model encompassing resources， environment， society， and technology was constructed， with the weights of each subsystem quantified using the entropy weight method. By coupling Shared Socioeconomic Pathways (SSPs)， five development scenarios suitable for this research were designed. The SD-SSPs model was then employed to predict the spatiotemporal differentiation of the Sustainable Development Index for these resource-based cities from 2025 to 2035.[Results] In terms of temporal evolution， during 2004–2024， the sustainable development index of resource-based cities in the Yellow River “Jizi bend” rose at an annual average rate of 8.2%， with severe subsystem contribution imbalance and lagging environmental governance. Spatially， policy responses and technological innovation have formed sustainable coordination systems in northwestern cities of the region， while eastern cities show slow green transition due to traditional resource economic dependence. Regarding development projections， SSP1 and SSP3 can increase the sustainable development index by 23%–35%. SSP4 leads to stagnated index growth due to intensified spatial differentiation， and SSP5 causes index recession due to late-stage resource overload. [Conclusion]The SD-SSPs coupled model identifies nonlinear synergistic interactions among multiple systems. The findings reveal that while the overall SDI of resource-based cities in the Yellow River "Jizi bend" region shows a significant growth trend， contributions from various subsystems remain unbalanced. Enhancing ecological and environmental governance， technological innovation， and institutional coordination can promote the sustainable development of these cities. However， it is crucial to guard against developmental decline caused by traditional path dependence and resource overload.

Characteristics of Floral Bud Differentiation and Floral Organ Development in Epimedium koreanum Nakai

[Objective]The floral organ development process and regularity of Epimedium koreanum were elucidated to provide theoretical basis for its artificial cultivation, flowering regulation and sexual reproduction technology.[Methods]From mid-March to mid-November at a cultivation base in Tonghua, Jilin, samples of underground rhizome buds were collected at approximately 7-day intervals. The samples were fixed in FAA, subjected to series dehydration and critical point drying, and then continuously observed and documented using a stereomicroscope and scanning electron microscope.[Results]The results indicated that floral bud differentiation in E. koreanum begins in late June of the current year. It progresses through the bud primordium stage, inflorescence primordium stage, and floret development stage, completing morphogenesis by late October before entering overwintering dormancy.Development resumes in late March of the following year, with flowering occurring in early May, spanning approximately 10 months in total. Floret differentiation follows an acropetal sequence, and floral organ differentiation proceeds in the order: sepals(two whorls)→outer whorl petals→inner whorl and stamens petals(almost simultaneously)→pistil. The pistil develops into a bottle-shaped carpel,the stamen anthers exhibit a basic anther wall structure, and the pollen is tricolpate and spherical. During spring the floral organs development rapidly, the inner whorl petals form a spur approximately 3 cm long at their base. The anthers dehisce upwards on the adaxial side, and the stigma papillae possess secretory functions. The floral organ structure of E. koreanum is complete and capable of normal sexual reproduction. The low natural seed set rate is likely primarily due to reduced pollination efficiency caused by low early spring temperatures.[Conclusion]In cultivation, harvesting of medicinal material should be avoided during the critical floral organ differentiation period from July to August. It is recommended to perform artificial pollination during full bloom to improve seed yield.This study provides an important morphological foundation for germplasm selection and cultivation management of E. koreanum.

Impact of Sustainable Development Policy Goal Synergy on Green Total Factor Productivity in the Yellow River Basin

[Objective]To promote the practical needs of ecological protection in the Yellow River Basin, this study focuses on the core task of green transformation in the basin, to explore the impact mechanism of sustainable development policies on the green total factor productivity(GTFP) in the Yellow River Basin, thereby using this productivity level to accurately measure the actual effectiveness and progress of sustainable development in the region.[Methods]Using panel data from the Yellow River Basin spanning2009 to 2022, this study first employs natural language processing software to collect and organize policy documents, followed by quantitative analysis using text mining and entropy weighting methods. The GTFP in the basin is then measured using the Stochastic Benchmarking Model(SBM). Finally, a two-way fixed effects model is constructed to examine the relationship between sustainable development policies and GTFP.[Results]The results show that the degree of goal synergy in sustainable development policies has a significant role in promoting green total factor productivity, and the synergistic effect between the dual goals has the best promotion effect, while an excessive number of goals is not conducive to the improvement of green total factor productivity. The goal synergy degree of existing sustainable development policies has obvious governance effect on ecological protection in green total factor productivity, and the effect shows obvious regional heterogeneity.[Conclusion]In summary, this study addresses the core challenges and practical demands of green development in the Yellow River Basin. By examining both policy refinement and governance enhancement, it proposes targeted optimization strategies and practical recommendations. These efforts not only provide solid practical support for sustainable development in the Yellow River Basin, but also offer replicable "Yellow River Experience" to boost green total factor productivity.

Development of a Multi-Trait Molecular Marker System and Its Application in Sorghum Breeding

[Objective]Genotypic identification is a prerequisite for efficient breeding， and there is an urgent demand for early-maturing and dwarf varieties in the sorghum-producing regions of Heilongjiang Province. This study aimed to establish a sorghum genotyping system based on functional markers and InDel markers to provide technical support for molecular marker-assisted breeding. [Methods]Using 24 sorghum backbone lines from Heilongjiang Province as validation materials， allelic variations were identified using molecular markers of 14 cloned functional genes. Meanwhile， the genome-wide detection system was developed based on the 35 pairs of InDel markers， which were developed based on resequencing data， as well as 40 pairs of SSR markers. [Results]Functional marker genotyping and InDel marker analysis revealed that the synergistic effect of dw3-sd7 with aa or dw1 significantly reduced plant height. All 24 lines carried mutations in the photoperiod-sensitive gene ma1， and additional mutations in ma5 and ma6 synergistically shortened the maturity period; however， some lines with the same functional genotype exhibited a difference of up to 26 days in maturity， suggesting the existence of unknown regulatory genes. The 35 pairs of InDel markers effectively distinguished sister lines with highly similar field phenotypes and compensated for gaps in marker coverage in certain chromosomal regions. [Conclusion]The combined functional marker and InDel marker system established in this study enables rapid genotyping of sorghum germplasm for traits such as plant height， maturity， and grain quality， providing a practical technical solution for parental selection， variety identification， and molecular marker-assisted breeding.

Design and Experiment of Spraying Device for Rice Seedling Nursery Assembly Line

[Objective]In order to solve the problems of poor spray uniformity and low stability of the spraying device of high -speed rice industrial seedling raising assembly line， which led to the waste of chemicals and water， a spraying device was designed. [Method] Through the analysis of the spraying process， the key parts and working parameters were determined; using Fluent fluid simulation， several different spray pipeline structures were studied. The single-factor and three-factor three-level response surface tests of the sprinkler pedestal were carried out using the angle between the sprinkler holes and the horizontal plane， the aperture diameter of the sprinkler holes， and the height of the sprinkler pipe as the test factors， and the Christensen's coefficient of uniformity， Cu， and the coefficient of variation， Cv， as the evaluation indexes.[Results]:The results showed that the order of the influence of each factor on the spray uniformity and stability is ranked as the size of the spray pipe aperture， the size of the spray hole and the horizontal angle size and the height of the spray pipe; through the extreme value analysis and ANOVA， the optimal parameter combination is obtained as the size of the angle between the spray hole and the level of 60°， the size of the spray hole of 1.27 mm， and the height of the spray pipe of 29.8 mm， then the uniformity coefficient of the spray is 95.189%， and the coefficient of variation 5.988%. [Conclusion]The results of the study can provide a reference for the optimal design of the spraying device in the rice factory seedling production line.

Soil-sickness Problem in the sustainable Development for the Protected Production of Vegetables

As the development of specialized production of vegetable crops, soil sickness has been a problem for the sustainable production of vegetable crops. Soil sickness is mainly caused by soil--borne pests, disorder of soil physical and chemical properties, and autotoxicity. The present paper discussed possible role of cropping system, biological control and grafting in the soil--borne pest control, role of organic fertilizer, desalting and reasonable fertilization in soil restoration, and the alleviation of autotoxicity by grafting, adsorption with charcoal and degradation by microbes.

Current Situation and Prospects of Green House Industry Development in China

This paper summarized comprehensively the history, current development of the green house industry and its researches. The historic significance, problems, and prospects were also analyzed. The summary was expected to provide references for determining the historic position and future developmental direction of green house industry.

Effect of Lodging Resistance on Yield and Its Relationship with Stalk Physical Characteristics

Stalk physical characteristics and tilt angle of matured plant of eighteen populations from six cultivars wereinvestigated under three conditions. The relationships between lodging resistance and yielding were also studied. TheresultS indicated that: the intensity of lodging of rice population could be grouped into three categories-lodging, slantand erect types according to the tilt angle of matured plant. Lodging resistance is significantly negatively correlatedwith the length of the first internode, and significantly positively correlated with the area of the basal stalk and withthe thickness of the hasal stalk. Difference among varieties and lodging resiStance was also found. Nitrogenapplication also had an obvious effect upon population lodging of rice. But if only yielding was considered, the highyield populations were given usually in the medium fertilization treatment. Therefore, rice resistance to the lodgingcould be improved by means of shortening length between the first and the second internode, strongtheningthe hardnes of the basal stalk, lowering the position of panicle, and elonging panicle or the neck-panicle internode.So the contradiction between lodging resiStance and plant height could be settled at a level of higher yielding.

Comparison of A New Model of Light Response of Photosynthesis with Traditional Models

Photosynthetic rates increase gradually with light intensity in the traditional models of light response curve of photosynthesis,i.e.rectangular hyperbolic model and nonrectangular hyperbolic model.So the maximum net photosynthetic rates calculated by nonrectangular hyperbolic model and rectangular hyperbolic model were far more than the measured data,and the saturation light point was not obtained.A new model of light-response of leaf net photosynthesis was proposed in this paper.Some properties of the new model of light-response of leaf net photosynthesis were discussed in detail.Results showed that the data of light-response of leaf photosynthesis of winter wheat under different environmental conditions were modeled by three models.The results fitted by nonrectangular hyperbolic model,rectangular hyperbolic model and the new model were compared.In addition,the measured data of light response of photosynthesis under different temperatures and CO2 concentrations could be dealt with,and the main parameters of photosynthesis,i.e.the maximum photosynthetic rates,saturation light point,light compensation point and the rate of dark expiration could be calculated without any hypotheses.The response data of leaf photosynthetic rate to irradiance under low irradiance and photo inhibition could be fitted by the new model.The measured data of light response of photosynthesis under different temperatures,CO2 concentrations and light intensity,including at low photon fluxes and photo inhibition could be dealt with.The fitted results were tallied with very well the measured data.So the new model has generality.

Current Situation of Remediating Techniques of Petroleum Contaminated Soil and Its Prospects

Current situations and damage of petroleum contaminated soils were summarized. Several main methods and techniques of remediating petroleum contaminated soil, application as well as advantages and disadvantages of the techniques were introduced in the paper. It points that traditional methods and techniques should combined with the bioremediation in the process cleaning the pollution, which will play the advantages of respective techniques. In the same time, the economic benefit, social benefit and environmental benefit should be considered together in treating petroleum contaminated soils.

A COMPARISON OF METHODS OF MEASUREMENT OF CHLOROPHYL IN PLANTS

Current Situation and Prospects of Green House Industry Development in China

This paper summarized comprehensively the history, current development of the green house industry and its researches. The historic significance, problems, and prospects were also analyzed. The summary was expected to provide references for determining the historic position and future developmental direction of green house industry.

Determination of Blueberry Anthocyanins through pH Differential Method

For determinieg the contents of blueberry anthocyanins more exactly,the blueberry pigments were extracted by acidic alcohol and were identified anthocyanins by UV-VIS spectra and chemical methods.The blueberry anthocyanins were quantitatively analyzed through pH differential method.The results indicated that the content of blueberry anthocyanins was 313.24mg.100g-1 and the relative standard deviation was 1.39%.The influence on measuring results by impurity in the solution was eliminated by pH differential method.

Status and Developing Prospects of Biopesticide Research and Application

Biopesticides have many advantages over the traditional chemical pesticides,being safe to human,livestock and nontarget organisms,having wonderful environmental compatibility,stable controlling effects and benefit to protect the biodiversity,and having many resources etc.Status of research and application of biopesticides were reviewed in this paper.The authors pointed out the major problems in the research and application of biopesticides.The developing prospects of biopesticides were discussed and some advices were given for biopesticide development in future.

Current Situation of Remediating Techniques of Petroleum Contaminated Soil and Its Prospects

Current situations and damage of petroleum contaminated soils were summarized. Several main methods and techniques of remediating petroleum contaminated soil, application as well as advantages and disadvantages of the techniques were introduced in the paper. It points that traditional methods and techniques should combined with the bioremediation in the process cleaning the pollution, which will play the advantages of respective techniques. In the same time, the economic benefit, social benefit and environmental benefit should be considered together in treating petroleum contaminated soils.