Agronomy最新文献

{"title":"The Study of Selenium Fertilizer on the Growth of Xiangzayou 787 and Related Molecular Mechanism","authors":"Qi Zhang, Jiayuan Peng, Yuqi Liu, Chunfeng Xie, Zhenqian Zhang","doi":"10.3390/agronomy14092032","DOIUrl":"https://doi.org/10.3390/agronomy14092032","url":null,"abstract":"Rapeseed is the largest self-produced oil crop in China which plays an important role in ensuring the safety of edible oil. However, its current per unit yield is far below Canada and Europe. In this study, selenium fertilizer and other micro fertilizers were sprayed on Xiangzayou 787 at the seedling stage. The results showed that the yield per plant increased 24.3% with sprayed selenium compared to the control (CK). Compared with the CK, the chlorophyll content in leaves at the flowering stage was significantly increased by 20.8%, and the soluble sugar content in the silique wall and seeds at the maturity stage was significantly increased and increased by 62.1% during the budding stage. The functional leaves of Xiangzayou 787 with the sprayed selenium fertilizer and the CK were used as raw materials for absolute quantitative transcriptome sequencing analysis. Accompanied with bioinformatics analysis, six differential genes which affect growth were discovered. The expression level of the protein phosphatase 2C gene in the silique wall was significantly higher than that of the CK. The PP2C78 gene was significantly positively correlated with the chlorophyll and soluble sugar content in leaves and the correlation coefficients were 0.539 and 0.547. According to gene expression levels, yield, and physiological indicators, PP2C78 may be a key functional gene affecting rapeseed yield. In this study, selenium fertilizer was found to be an excellent foliar fertilizer for rapeseed; the PP2C78 gene may be helpful for analyzing the yield increasing mechanism and used as a reference for screening new foliar fertilizers.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Different Post-Flowering Photoperiods on Main Agronomic Traits of Strawberry (Fragaria × ananassa Duch. cv. Akihime)","authors":"Cai Ren, Lamei Jiang, Weizhi Chen, Ziyi Wang","doi":"10.3390/agronomy14092039","DOIUrl":"https://doi.org/10.3390/agronomy14092039","url":null,"abstract":"Reproductive growth is one of the most important stages in the life history of plants and is regulated by photoperiod. However, the effect of different photoperiods after flowering on the reproductive growth stages of different plants and their roles is still unclear. For this reason, this study took the short-day plant strawberry (Fragaria × ananassa Duch. cv. Akihime) as the research object, performed different photoperiod treatments (ND: natural daylight; SD: short daylight; LD: long daylight) after flowering, and studied the effects of photoperiod on fruit growth period, fruit quality, flower opening, and plant height in different inflorescence of fruits. The results showed that different photoperiods had significantly different effects on the growth and development of strawberries after flowering, and LD and SD had opposite effects: (1) Under the condition of SD, the fruit matured after 17 days of treatment, while the LD and ND advanced this by 6 and 5 days. LD could significantly delay the development of the first inflorescence of fruits, resulting in longer ripening period and fruit appearance, and the quality traits were better. (2) The number of flowers in the secondary inflorescence and the development process was effectively accelerated by LD, and the total number of flowers under the long-day treatment was significantly more than that under the short-day treatment and the natural condition from 12 to 25 days after the end of the flowering period. Under the condition of LD, the fruits matured after 53 days of treatment, which was 5 days earlier than the other two treatments, and the period from flowering to maturity was shortened. (3) The effect of different photoperiods on the final plant height of strawberries after flowering had no significant difference (p < 0.05). In conclusion, this study found that photoperiod could effectively regulate the reproductive growth stage of strawberry after flowering, which enriched the experimental material and theoretical basis for studying the photoperiod as a mechanism for regulating plant growth and development, providing technical guidance for artificial regulation of strawberry growth period and fruit quality.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"228 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regulatory Effects of Different Biochar on Soil Properties and Microbial Community Structure in Chrysanthemum Continuous Cropping Soil","authors":"Yang Feng, Xin Hu, Yanhuan Guan, Zhixuan Chu, Xianfeng Du, Yuyan Xie, Shiqi Yang, Siru Ye, Lei Zhang, Jinyi Ma, Haoming Chen","doi":"10.3390/agronomy14092034","DOIUrl":"https://doi.org/10.3390/agronomy14092034","url":null,"abstract":"Chrysanthemum, an agricultural economic crop with ornamental, medicinal, and edible values, faces the problem of continuous cropping obstacles in its cultivation. As a potential soil conditioner used to address continuous cropping obstacles (CCOs), the applicability of biochar in chrysanthemum cultivation has become a research hotspot. This study explored the effects of three different types of biochar (rice straw biochar = RB, pig manure biochar = PB, and sludge biochar = SB) on soil for chrysanthemum that had been continuously cultivated for eight years through pot experiments. The results indicate that the addition of biochar significantly reduced soil water loss. Compared with CK, the water retention rates of the SB and PB treatments increased by 25.4% and 18.4%, respectively. In the PB treatment, the contents of available phosphorus (AP) and available potassium (AK) increased by 85% and 164%, respectively. The available nitrogen (AN) content showed the highest increase under the SB treatment. All three types of biochar could improve the pH value of chrysanthemum soil with CCOs (increased by 0.4–5.4%). The results of microbial community diversity showed that, compared with CK, PB and RB slightly reduced the diversity of bacterial communities in chrysanthemum soil with CCOs (by 1.50% and 0.41%, respectively). However, the SB treatment increased the diversity of bacterial communities in chrysanthemum soil with CCOs (by 0.41%). At the same time, SB and PB significantly inhibited the diversity of fungal communities (reduced by 15.15% and 6.67%, respectively), while RB promoted the diversity of fungal communities (increased by 5.45%). Furthermore, the analysis results of bacterial phyla and genera indicated that PB and SB had enhancing effects on the beneficial bacterial phylum Actinobacteriota (8.66% and 4.64%) and the beneficial bacterial genus Nocardioides (23.29% and 9.69%). Additionally, the PB treatment enhanced the beneficial bacterial phylum Firmicutes (7.03%). The analysis results of fungal genera and phyla indicated that PB contributed to an increase in the beneficial fungal phylum Ascomycota (1.51%). RB significantly enhanced the beneficial fungal genus Chaetomium (56.34%). Additionally, all three types of biochar effectively reduced the abundance of the harmful fungal phylum Basidiomycota (30.37–73.03%). In the PB and SB treatments, the harmful fungal phylum Mucoromycota was significantly decreased (by 36.22% and 62.60%, respectively). Finally, all three types of biochar reduced the abundance of harmful fungal genera Acremonium (1.15–35.19%) and Phoma (97.1–98.7%). In this study, we investigated the effect of three kinds of biochar (RB, PB, and SB) on the soil of chrysanthemum continuous cropping through potting experiments and found that they could significantly reduce water loss, enhance water retention, increase the soil nutrient content, improve the pH value, regulate microbial communities, increase beneficial microorganisms, and r","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of Application Parameters for UAV-Based Liquid Pollination in Pear Orchards: A Yield and Cost Perspective","authors":"Pei Wang, Moxin He, Mingqi Li, Yuheng Yang, Hui Li, Wanpeng Xi, Tong Zhang","doi":"10.3390/agronomy14092033","DOIUrl":"https://doi.org/10.3390/agronomy14092033","url":null,"abstract":"Unmanned aerial vehicle (UAV) liquid pollination emerges as a promising substitute for hand pollination methods. In this study, the relationship between UAV liquid pollination and fruit thinning operations was explored from the perspective of practical application. By testing droplet deposition under various flight parameters, the flight parameters for a specific pear orchard were optimized to ensure the uniform and effective distribution of the pollination solution. Results indicated that optimal droplet density (number·cm−2), area coverage (%), and deposition rate (μL·cm−2) were achieved at a flight height (FH) of 1.5 m and a flight speed (FS) of 2 m·s−1. Considering the nuanced physiological attributes of pear tree flowers during their pollination phase, the research scrutinizes the impact of application parameters such as floral stage and spraying frequency on pollination efficiency. A two-way ANOVA analysis demonstrated significant impacts of floral stage, spraying frequency, and their interaction on the fruit set rate (p < 0.01). Controlling pollination parameters can effectively regulate the fruit set rate, thereby influencing the cost and efficiency of fruit thinning. These findings contribute a theoretical framework for formulating customized pollination management strategies tailored to the specific needs of pear orchards.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Phytochrome-Interacting Factor Gene CaPIF7a Positively Regulates the Defense Response against Phytophthora capsici Infection in Pepper (Capsicum annuum L.)","authors":"Yu Li, Dan Wu, Ting Yu, Bing Liu, Xuchun Gao, Huibin Han, Jinyin Chen, Yong Zhou, Youxin Yang","doi":"10.3390/agronomy14092035","DOIUrl":"https://doi.org/10.3390/agronomy14092035","url":null,"abstract":"Phytochrome-interacting factor (PIF) is a subfamily of the basic helix–loop–helix (bHLH) transcription factors (TFs) and plays key roles in plant responses to diverse biotic and abiotic stresses. In this work, a PIF gene named CaPIF7a was cloned and its role in the regulation of pepper’s resistance to Phytophthora capsici infection (PCI) was studied. The cloned CaPIF7a gene has a CDS length of 1383 bp, encodes a hydrophilic protein containing bHLH and APB characteristic domains, and subcellular localization results showed that CaPIF7a was located in the nucleus. Expression analysis showed that CaPIF7a gene has the highest expression level in leaf, and its expression was regulated under PCI and salicylic acid (SA) treatment. Silencing of CaPIF7a in pepper plants by virus-induced gene silencing (VIGS) reduces the resistance of pepper to PCI, with decreased expression of SA-responsive and SA-biosynthesis genes and obviously decreased SA content. DNA affinity purification sequencing (DAP-seq) was employed to identify the potential targets of CaPIF7a, and yeast one-hybrid (Y1H) verified that CaPIF7a could regulate the expression of CaHY5 by binding its promoter. These findings indicated that CaPIF7a might be a key modulator in plant immune response and presented a possible regulatory network of CaPIF7a in PCI.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of Clubroot Disease Resistance in Brassica juncea Germplasm at the Seedling Stage","authors":"Wenlong Yang, Jiangping Song, Xiaohui Zhang, Chu Xu, Jiaqi Han, Zhijie Li, Yang Wang, Huixia Jia, Haiping Wang","doi":"10.3390/agronomy14092042","DOIUrl":"https://doi.org/10.3390/agronomy14092042","url":null,"abstract":"Infection by the mustard clubroot disease pathogen Plasmodiophora brassicae has a significant negative impact on the quality and yield of Chinese mustard (Brassica juncea). At present, screening resistant resources for breeding programs is the most economical and effective method available to control this disease. In this study, we isolated P. brassicae physiological race 4 from Chinese cabbage and examined 483 mustard germplasm resources (193 leaf mustard, 96 stem mustard, and 194 root mustard) from China and abroad to identify resistance to clubroot disease at the seedling stage through irrigation inoculation with the isolated pathogen. The results showed that there were no immune varieties among the tested mustard germplasm, but that there were differences in resistance to clubroot disease among the three mustard types. More than 90% of leaf and stem mustard resources were susceptible to clubroot disease, whereas 38.66% of root mustard resources showed resistance. In total, we detected 4 highly resistant, 9 resistant, and 83 moderately resistant varieties, of which 4 highly resistant, 8 resistant, and 63 moderately resistant varieties were root mustard resources, whereas only 1 resistant and 5 moderately resistant varieties were stem mustard resources, and 15 moderately resistant varieties were leaf mustard resources. In addition, we used seven molecular markers for clubroot disease resistance in Chinese cabbage to detect stem and root mustard resources. The results showed that the marker CRk was detected in 97.87% of stem mustard and 92.49% of root mustard resources. Six markers (Crr1, Crr2, Crr3, CRa, CRb, and CRc) were detected in 18.09%, 7.45%, 2.13%, 6.38%, 12.77%, and 12.77% of stem mustard germplasms, and four markers (Crr1, Crr2, Crr3, and CRc) were detected in 8.09%, 8.67%, 10.40%, and 8.67% of root mustard germplasms, respectively, suggesting that these markers are not suitable for detecting mustard germplasm resistance to clubroot disease. This study provides a technical reference and material support for the breeding of mustard varieties resistant to clubroot disease.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"268 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lightweight Wheat Spike Detection Method Based on Activation and Loss Function Enhancements for YOLOv5s","authors":"Jingsong Li, Feijie Dai, Haiming Qian, Linsheng Huang, Jinling Zhao","doi":"10.3390/agronomy14092036","DOIUrl":"https://doi.org/10.3390/agronomy14092036","url":null,"abstract":"Wheat spike count is one of the critical indicators for assessing the growth and yield of wheat. However, illumination variations, mutual occlusion, and background interference have greatly affected wheat spike detection. A lightweight detection method was proposed based on the YOLOv5s. Initially, the original YOLOv5s was improved by combing the additional small-scale detection layer and integrating the ECA (Efficient Channel Attention) attention mechanism into all C3 modules (YOLOv5s + 4 + ECAC3). After comparing GhostNet, ShuffleNetV2, and MobileNetV3, the GhostNet architecture was finally selected as the optimal lightweight model framework based on its superior performance in various evaluations. Subsequently, the incorporation of five different activation functions into the network led to the identification of the RReLU (Randomized Leaky ReLU) activation function as the most effective in augmenting the network’s performance. Ultimately, the network’s loss function of CIoU (Complete Intersection over Union) was optimized using the EIoU (Efficient Intersection over Union) loss function. Despite a minor reduction of 2.17% in accuracy for the refined YOLOv5s + 4 + ECAC3 + G + RR + E network when compared to the YOLOv5s + 4 + ECAC3, there was a marginal improvement of 0.77% over the original YOLOv5s. Furthermore, the parameter count was diminished by 32% and 28.2% relative to the YOLOv5s + 4 + ECAC3 and YOLOv5s, respectively. The model size was reduced by 28.0% and 20%, and the Giga Floating-point Operations Per Second (GFLOPs) were lowered by 33.2% and 9.5%, respectively, signifying a substantial improvement in the network’s efficiency without significantly compromising accuracy. This study offers a methodological reference for the rapid and accurate detection of agricultural objects through the enhancement of a deep learning network.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Image Processing and Support Vector Machine (SVM) for Classifying Environmental Stress Symptoms of Pepper Seedlings Grown in a Plant Factory","authors":"Sumaiya Islam, Samsuzzaman, Md Nasim Reza, Kyu-Ho Lee, Shahriar Ahmed, Yeon Jin Cho, Dong Hee Noh, Sun-Ok Chung","doi":"10.3390/agronomy14092043","DOIUrl":"https://doi.org/10.3390/agronomy14092043","url":null,"abstract":"Environmental factors such as temperature, humidity, light, and CO2 influence plant growth, and unfavorable environmental conditions cause stress in plants, producing symptoms in their early growth stages. The increasing importance of optimizing crop management strategies has led to a rising demand for the precise evaluation of stress symptoms during early plant growth. Advanced technologies are transforming plant health monitoring through enabling image-based stress analysis. Machine learning (ML) models can effectively identify the important features and morphological changes connected with various stress conditions through the use of large datasets acquired from high-resolution plant images. Therefore, the objective of this study was to develop a method for classifying the early-stage stress symptoms of pepper seedlings and enabling their identification and quantification using image processing and a support vector machine (SVM). Two-week-old pepper seedlings were grown under different temperatures (20, 25, and 30 °C), light intensity levels (50, 250, and 450 µmol m−2s−1), and day–night hours (8/16, 10/14, and 16/8) in five controlled plant growth chambers. Images of the seedling canopies were captured daily using a low-cost red, green, and blue (RGB) camera over a two-week period. Eighteen color features, nine texture features using the gray-level co-occurrence matrix (GLCM), and one morphological feature were extracted from each image. A two-way ANOVA and multiple mean comparison (Duncan) analysis were used to determine the statistical significance of the treatment effects. To reduce feature overlap, sequential feature selection (SFS) was applied, and a support vector machine (SVM) was used for stress classification. The SFS method was used to identify the optimal features for the classification model, leading to substantial increases in stress classification accuracy. The SVM model, using these selected features, achieved a classification accuracy of 82% without the SFS and 86% with the SFS. To address overfitting, 5- and 10-fold cross-validation were used, resulting in MAEs of 0.138 and 0.163 for the polynomial kernel, respectively. The SVM model, evaluated with the ROC curve and confusion matrix, achieved a classification accuracy of 85%. This classification approach enables real-time stress monitoring, allowing growers to optimize environmental conditions and enhance seedling growth. Future directions include integrating this system into automated cultivation environments to enable continuous, efficient stress monitoring and response, further improving crop management and productivity.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence of Polycyclic Aromatic Hydrocarbons (PAHs) in Pyrochar and Hydrochar during Thermal and Hydrothermal Processes","authors":"Hwang-Ju Jeon, Donghyeon Kim, Fabiano B. Scheufele, Kyoung S. Ro, Judy A. Libra, Nader Marzban, Huan Chen, Caroline Ribeiro, Changyoon Jeong","doi":"10.3390/agronomy14092040","DOIUrl":"https://doi.org/10.3390/agronomy14092040","url":null,"abstract":"Pyrochar (Biochar) produced from the thermochemical conversion of biomass has been widely used as a soil amendment to improve agricultural soil quality. Since polycyclic aromatic hydrocarbons (PAHs) can be produced in such processes, the occurrence of PAHs in pyrochars has been extensively studied, and standards such as the European Biochar Certificate (EBC) and International Biochar Initiative (IBI) contain limit values for biochars applied to soils. However, studies on PAH levels in hydrochars from hydrothermal processes, which can be an alternative to wet biomass are scarce. This study focuses on comparing the occurrence of 16 PAHs regulated by the US EPA in 22 char samples (including pyrochars from pyrolysis, hydrochars from hydrothermal carbonization, and, for the first time, hydrothermal humification) using an ultrasonic extraction method. Results showed that the sum of the 16 EPA PAHs in all samples was well below the requirements of the two standards, except for pyrochar produced at the farm scale. They ranged from 131 to 9358 µg·kg−1 in the seven pyrochars and from not detected to 333 µg·kg−1 for the fourteen hydrochars. Our findings indicate that hydrochar produced via hydrothermal methods exhibits much lower concentrations and is a safe option for soil amendment and environmental applications.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing Germplasm Variation and Tolerance Thresholds of Bermudagrass (Cynodon dactylon) to Neutral and Alkaline Salt Stress in Ecological Restoration","authors":"Lisi Tang, Wen Li, Qikun Yu, Zongjiu Sun, Peiying Li","doi":"10.3390/agronomy14092023","DOIUrl":"https://doi.org/10.3390/agronomy14092023","url":null,"abstract":"Bermudagrass (Cynodon dactylon), a salt-tolerant species surviving in environments with pH up to 9.3, and it exhibits variable germination responses under salt and alkaline stress. This study evaluates the impact of neutral and alkali salts with varying pH levels on bermudagrass seed germination. Six bermudagrass germplasm accessions were analyzed using neutral (NaCl: Na2SO4 = 1:1, pH 6.12–7.14) and alkali (NaHCO3:Na2CO3 = 1:1, pH 9.62–9.90) salt treatments. Salt concentrations ranged from 0 to 250 mmol/L, with increments of 25 mmol/L. The assessed parameters included seed germination rate, germination potential, germination index, radicle length, plumule length, seedling weight, and radicle and plumule length ratio. The salt tolerance threshold of each germplasm was calculated using a linear regression fitting model. Critical indicators of salt tolerance were selected through stepwise regression, and the salt-alkali tolerance ranking was determined using a combined membership function and discriminant analysis. The results indicated that the total score decreased with increasing salt concentration under neutral salt stress. Alkali salt stress was more damaging to bermudagrass seedlings than neutral salt stress, inhibiting germination at 50 mmol/L. Neutral salt tolerance thresholds ranged from 31.7 to 207.7 mmol/L, while alkaline salt tolerance thresholds ranged from 16.9 to 53.3 mmol/L. The six germplasm accessions exhibited different responses to salt and alkali stress. Key indicators for neutral salt tolerance included plumule length, radicle and plumule length ratio, and seedling weight. For alkali salt tolerance, key indicators were germination potential, radicle length, and seedling weight, which can be used to screen for resistant germplasms. Our study demonstrates that alkaline salts inhibit seed germination and seedling growth more than neutral salts, and pH affects root growth and the radicle-to-plumule length ratio in seedlings. This research has significant ecological implications, providing insights into the adaptation strategies of bermudagrass in salt-affected and alkaline environments, which could aid in the restoration and management of degraded ecosystems.","PeriodicalId":7601,"journal":{"name":"Agronomy","volume":"257 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}