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Article

Comprehensive Evaluation and Screening for Salt Tolerance Germplasms at Seedling Stage in Eggplant

by
Yu Fang
,
Zhiguo Wang
,
Yingnan Du
,
Shuaitao Di
,
Zhenwei Gao
,
Xueping Chen
,
Weiwei Zhang
,
Lijun Song
,
Shuangxia Luo
* and
Qiang Li
*
Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China
*
Authors to whom correspondence should be addressed.
Horticulturae 2025, 11(6), 697; https://doi.org/10.3390/horticulturae11060697
Submission received: 6 May 2025 / Revised: 12 June 2025 / Accepted: 14 June 2025 / Published: 17 June 2025

Abstract

:
Salt stress presents a major environmental constraint to global agricultural productivity and crop yield stability. Eggplant (Solanum melongena L.) is one of the most extensively cultivated Solanaceae crops worldwide, and the characterization of its germplasm for salt tolerance is essential to develop breeding programs to target its abiotic stress resilience. In this study, 200 mmol/L NaCl was identified as the initial screening concentration for the discrimination of salt tolerance levels in eggplant seedlings. Salt tolerance indices derived from 13 descriptors, including the plant height, stem diameter, and leaf number, were used to evaluate 165 germplasm resources (108 inbred lines and 57 commercial cultivars). These 165 germplasms were grouped into five groups, and six highly tolerant and eight highly sensitive germplasms were identified. Importantly, a stepwise multiple linear regression model incorporating the root surface area, leaf number, leaf water content, malondialdehyde content, and stem water content achieved 90.02% predictive accuracy, establishing a high-throughput screening protocol for germplasm selection. This systematic approach provides methodological advancements for precision breeding and identifies key physiological and morphological markers for salt tolerance improvement in eggplant.

1. Introduction

Soil salinization is an increasingly severe global phenomenon that significantly affects plant growth and agricultural production [1]. Currently, approximately 1 billion hectares of land worldwide are affected by excess salinity, accounting for about 7% of the global land area, and this is growing at a rate of 2 million hectares per year [2,3]. China ranks third globally in terms of its saline–alkali land area, with 99.13 million hectares, including 9.913 million hectares affected by excess salinity, which is equivalent to ~10% of the global total of 1 billion hectares [4].
Salt stress disrupts many stages of crop life cycles, including seed germination, vegetative growth, and reproductive development, and poses a critical threat to sustainable agricultural production and food security [5,6]. Crops employ a variety of morphological, physiological, biochemical, and molecular adaptive strategies to mitigate salt stress [7]. For example, osmotic regulation maintains ion homeostasis; vacuolar sequestration prevents cytotoxic ion accumulation; and enhanced antioxidant enzyme activity protects against oxidative damage [8]. Consequently, numerous screening or breeding programs have been developed to create salt-tolerant crop varieties and to improve saline–alkali land utilization and alleviate food shortages [9,10]. Notable examples include Nangengyan No. 1, a salt-tolerant rice cultivar developed by the Jiangsu Academy of Agricultural Sciences, which achieved an average yield of 544.2 kg/667 m2 under 0.5% saline irrigation in 2019 while meeting the Grade 2 quality standards of China’s edible rice industry (NY/T 593–2021) [11]. The Chinese wheat breeding program includes over 700 lines under salt–alkali tolerance evaluation, with Hangmai 802 yielding over 0.675 kg/m2 on moderately saline–alkali soils [12]. Similarly, the Chinese Academy of Sciences screened 2000 soybean accessions to breed Dongsheng 118, a high-yielding variety that produces 0.225 kg/m2 on heavily saline–alkali soils (pH 9.0), surpassing the national average of 0.195 kg/m2 on standard farmland [13]. These examples demonstrate the potential of breeding crops for both high salt tolerance and high yields.
Studies indicate that salt tolerance varies across plant growth stages. For example, pepper hybrids exhibit greater resilience during germination than at the seedling stage, with the germination rates declining significantly only at 150 mmol/L NaCl, whereas seedling growth descriptors (e.g., plant height, leaf area, biomass) are reduced at 10 mmol/L NaCl treatment [14]. Rice seedlings exposed to saline water (8–12 dS/m) for 24 days showed reduced root lengths, fresh/dry biomass, and root dry weights compared with controls [15]. Similarly, oat seedlings treated with 300 mmol/L NaCl for 15 days exhibited marked reductions in plant height, root elongation, and water content [16]. These findings underscore the importance of screening at the early growth stage for salt tolerance.
Principal component analysis (PCA) and membership function analysis (MFA) provide robust methods for salt tolerance evaluation and have been widely applied in crops such as oats and alfalfa [6,16,17]. For example, Zhang classified 100 oat varieties into three groups (17 salt-tolerant, 27 moderately tolerant, 56 sensitive) using PCA and MFA [16]. Benabderrahim identified three salt-tolerant alfalfa genotypes from 36 accessions using tolerance indices and PCA [17]. Yu et al. integrated PCA, MFA, cluster analysis, and stepwise regression to categorize 20 alfalfa germplasms into four tolerance classes and developed a predictive model (95.95% accuracy) based on the stem biomass, Na+/K+ ratio, and shoot–root fresh weight ratio [6]. Alternative approaches, such as salt tolerance indices (STIs), have also been used to classify maize [18,19]. Masuda grouped 20 maize lines into four categories (highly tolerant to sensitive) using STIs (0.49; 0.27 < STI < 0.40; 0.12 < STI < 0.24; STI < 0.10) [18], while Sultana identified BARI No. 5 as the most salt-tolerant of four maize varieties (BARI No. 5 > Mosaic Corn > BARI No. 7 and Common Corn) under saline–alkali conditions [19].
Eggplant (Solanum melongena L.) is a globally significant Solanaceous crop that is moderately sensitive to salt stress [20,21]. China leads global eggplant production, with 833,200 cultivated hectares and 39.28 million tons harvested in 2023 (FAOSTAT). Studies have shown growth stage-specific responses to salinity. For example, Kemer outperformed Pala and Aydin Siyahi during germination at 50–150 mmol/L NaCl, whereas Pala exhibited higher relative root and shoot biomass at 150 mmol/L [22]. Wu et al. identified the proline content and seedling vigor index as key indicators for rapid cultivar screening, classifying Funong Green Eggplant and Nongyou Long Eggplant as salt-tolerant varieties using PCA and MFA [23].
Despite advances in genetic and physiological research on eggplant salt tolerance, few salt-tolerant germplasms are currently available [24,25]. While the evaluation of natural populations has proven effective in maize, soybean, and rice [16,26,27], similar studies on eggplant remain limited. In this study, we evaluated 165 eggplant germplasms for seedling-stage salt tolerance and established a comprehensive evaluation model, providing insights for the precision phenotyping and breeding of salt-tolerant varieties.

2. Materials and Methods

2.1. Plant Materials

This study utilized 57 commercial eggplant varieties (Table 1) and 108 inbred lines (Table 2), provided by the Hebei Key Laboratory of Vegetable Germplasm Innovation and Utilization. A subset of 15 randomly selected germplasms (21C48, 21C41, 21C6, 21C170, 21C154, 21C9, 21C21, 21C16, 21C7, 21C207, 21C200, 21C4, 21C60, 21C243, and 21C145) was used to determine the appropriate NaCl concentration for subsequent experiments.

2.2. Determination of Optimal Salt Stress Levels

The fifteen germplasms listed in Section 2.1 were randomly selected and subjected to NaCl stress. Seeds were soaked in water at 55 °C and then sown into 12 × 12 × 9.4 cm square pots (five seeds per pot, three pots per treatment) containing peat moss, vermiculite, and perlite (1:1:1/v:v:v) on 12 June 2024. The seedlings were grown in a greenhouse at Hebei Agricultural University, Baoding (E 115°42′, N 38°81′). After cotyledon emergence, three seedlings were kept per pot. At the two-leaf stage, NaCl solutions (100, 200, 250, or 300 mmol/L) were applied as treatments on 29 June 2024, when the seedlings had at least three true leaves. Distilled water was used as the control. Each pot was treated with 250 mL of solution every 2–3 d, depending on the prevailing weather conditions, for a total of six applications over 15 days. Seedlings were harvested to measure the following growth descriptors: plant height (PH), root length (RL), leaf number (LN), leaf surface area (LSA), root fresh/dry weight (RFW/RDW), stem fresh/dry weight (SFW/SDW), and leaf fresh/dry weight (LFW/LDW).
The STI and salt sensitivity index (SSI) were calculated as
S T I = T r a i t   v a l u e   u n d e r   s a l t   s t r e s s T r a i t   v a l u e   u n d e r   c o n t r o l
S S I = 1 S T I

2.3. Salt Tolerance Screening of Germplasm

The seeds of the 165 germplasms were sown on 4 September 2024. On 29 September, when the seedlings had at least three true leaves, they were subjected to 200 mmol/L NaCl treatment (170 mL per pot). This was followed by two applications each of 300 mmol/L, 400 mmol/L, 500 mmol/L, and 600 mmol/L NaCl solutions. The control group received an equal volume of distilled water instead of the NaCl solution at each step. Following these treatments, the PH, stem diameter (SD), LN, chlorophyll content (Chl), LSA, malondialdehyde content (MDA), RL, root volume (RV), root surface area (RSA), root tip number (RTN), and root/stem/leaf water content (RWC/SWC/LWC) were measured. The STI values were derived for each trait. The seed treatments, square pot sizes, and substances were as described in Section 2.2. This experiment was performed at the greenhouse at Hebei Agricultural University, Baoding (E 115°42′, N38°81′).

2.4. Descriptor Measurements

PH: Measured from the substrate surface to the growth point using a steel ruler (0.01 cm precision). SD: Recorded 3 cm above the substrate using a digital caliper (0.01 mm precision). LN: Counted as fully expanded leaves from the first true leaf. LSA: Quantified using an LI-3100C leaf area scanner (LI-COR Biosciences, Cambridge, UK). Root architecture (RL, RSA, RV, RTN): Analyzed using a plant image analysis system (LA-S, Hangzhou Wanshen Detection, Hangzhou, China).

2.5. Evaluation of Seedling Physiological Indices

The fresh weight (FW) and dry weight (DW) of the roots, stems, and leaves were determined before and after oven drying at 70 °C to a constant mass. The water content was calculated as
W a t e r   C o n t e n t ( % ) = F W D W F W × 100 .
The chlorophyll content of the 3rd–4th leaves was measured using a SPAD-502PLUS chlorophyll meter (Konica Minolta, Tokyo, Japan). The malondialdehyde (MDA) content was measured using a thiobarbituric acid (TBA) assay. Fresh tissue (0.2 g) was homogenized in 10% trichloroacetic acid, centrifuged (12,000× g, 10 min), and the supernatant reacted with 0.67% TBA. Absorbance at 450, 532, and 600 nm was measured after boiling (30 min) and cooling.

2.6. Statistical Analysis

The coefficient of variation (CV) was calculated for each trait as
C V = μ σ × 100 % ,
where σ = standard deviation and μ = mean.
The subordinate function (U) and weight (Wi) were computed to derive the comprehensive salt tolerance descriptor (D):
U ( X i ) = X i X m i n X m a x X m i n W i = P i I = 1 n P i D = I = 1 n U ( X i ) × W i
where Xi = trait value, Xmax/min = maximum/minimum values, and Pi = principal component contribution of the ith trait value.
The data were analyzed using IBM SPSS Statistics v.26 and visualized using Origin 2021. Stepwise regression linked STI values (independent variables) to D values (dependent variable) to establish an optimal predictive model.

3. Results

3.1. Optimal Salt Concentration for Screening

Following 15 days of exposure to different concentrations of NaCl, ten growth-related traits (PH, LN, LSA, RL, RFW, RDW, SFW, SDW, LFW, LDW) were measured across 15 germplasms. The linear regression of the SSI showed SSI values of >0.2 under 100–300 mmol/L NaCl. At 200 mmol/L, the mean SSI for all traits was 0.480, with six traits (PH, LN, RL, RFW, SFW, LFW) showing values close to 0.5 (i.e., 0.574, 0.494, 0.470, 0.587, 0.538, and 0.594, respectively), indicating ~50% physiological impairment. This concentration was selected as the baseline of salt treatment for subsequent evaluations (Figure 1).

3.2. Variations in Salt Tolerance Indices

As summarized in Table 3, the STI analysis of 13 traits across 165 germplasms showed coefficients of variation (CVs) ranging from 4.67% (RWC) to 49.44% (LSA). The root and leaf architectural traits showed the highest variability—LSA (49.44%), RV (45.25%), RTN (43.80%), and RSA (42.79%)—highlighting differential trait sensitivity to salinity (Table 3).

3.3. Correlation Analysis of STI Using Different Indices in Seedlings

The correlation analysis grouped the 13 traits into three clusters. These were Cluster I: Chl, MDA, LN, and RWC; Cluster II: root-related traits (RTN, RL, RV, RSA); and Cluster III: LWC, pH, SWC, LSA, and SD (Figure 2). The strongest correlations occurred between RL and RSA (r = 0.907, p < 0.01), RSA and RV (r = 0.901, p < 0.01), and RL and RV (r = 0.704, p < 0.01). Weaker inter-cluster correlations (r < 0.50) underscored the need for multivariate analysis (Figure 2).

3.4. Principal Component Analysis of STI

PCA suitability was confirmed using a Kaiser–Meyer–Olkin (KMO) score of 0.644 and Bartlett’s test (p = 0.00) (Table 4). Seven principal components (PCs) cumulatively explained >80% of the variance (Table 4). PC1 (22.998% variance) showed high loadings for root traits (RSA, RL, RV, RTN), while subsequent PCs captured contributions from physiological and morphological traits (Table 5).

3.5. Membership Function Evaluation

The comprehensive weights (W1W7) for the seven PCs were 0.283, 0.165, 0.119, 0.111, 0.109, 0.108, and 0.106, respectively. The resultant comprehensive tolerance descriptors (D) ranged from 0.236 (21C60, highly sensitive) to 0.601 (24QX9, highly tolerant), enabling germplasm ranking (Table 6).

3.6. Germplasm Classification by Salt Tolerance

Hierarchical clustering based on the D values categorized the 165 germplasms into five groups: highly tolerant (6); tolerant (35); moderately tolerant (67); sensitive (49); and highly sensitive (8) (Figure 3, Table 7). Representative phenotypes of the extreme groups are shown in Figure 4.

3.7. Stepwise Regression Analysis of STIs Using Different Indices

In this study, the D value was used as the dependent variable and the salt tolerance STI of the 13 indices was used as the independent variable in a stepwise linear regression analysis, using the following equation:
D(F) = −0.424 + 0.206⋅RSA + 0.27⋅LN + 0.347⋅LWC + 0.049⋅MDA + 0.255⋅SWC
The model explained 90.1% of the variance (R2 = 0.9002), with 90.02% prediction accuracy, thus validating RSA, LN, LWC, MDA, and SWC as critical screening indicators (Figure 5).

4. Discussion

The establishment of evaluation methods for salt tolerance is of great significance for eggplant. In the present study, we determined the optimal concentration for NaCl treatment using 15 germplasms at the three-leaf stage and found that 200 mM can be used as the baseline for NaCl treatment. In the following experiments, 165 germplasms were initially treated with 200 mM NaCl, followed by 300, 400, 500, and 600 mM NaCl treatment. It is worth noting that the growth rates of the 165 germplasms were different, so it was impossible to treat the seedlings at the same stage with the same number of true leaves. Therefore, the seedlings of the 165 germplasms were initially treated with NaCl when all seedlings had at least three true leaves. Some studies indicate that different growth stages show different salt tolerances [14]. However, the stages are entirely different, such as the germination stage, seedling stage, or adult plant stage. In the present study, although the growth stages among the germplasms were not exactly the same, all of them were at the seedling stage, with different numbers of true leaves. Therefore, the methods for the evaluation of salt tolerance in the present study are reasonable and can provide a reference for other crops in salt tolerance evaluation.
Crop salt tolerance is a complex trait governed by coordinated metabolic pathways and genetic mechanisms, necessitating multi-indicator evaluations for comprehensive assessment [28]. Current screening methodologies integrate correlation analysis, PCA, MFA, cluster analysis, and linear regression to minimize the errors inherent in single-index approaches, thereby enhancing the reliability [29]. Among these, the STI has proven particularly effective in evaluating stress resilience [30].
The experimental salt concentration applied critically influences the screening outcomes: suboptimal levels may inflate false positives for tolerance, while excessive concentrations risk overestimating the sensitivity [31]. Previous studies have employed diverse methods to identify the optimal stress levels. Choudhary established a screening concentration for 278 wheat varieties by regressing the SSI values to identify the NaCl level inducing 50% sensitivity [32]. Similarly, Geng determined that 0.5% NaCl exposure over 4–6 weeks during tillering effectively differentiated rice genotypes [33]. In eggplant, Cebeci identified four highly salt-tolerant accessions (S. linnaeanum, S. incanum L., BB, MK) in 150 mmol/L NaCl treatments [34], while Hannachi observed cultivar-specific thresholds: tolerant genotypes (Bonica, Galine) tolerated 80 mmol/L NaCl with minimal Na+/Cl− accumulation, whereas sensitive varieties (Adriatica, Black Beauty) exhibited ion imbalances at 40 mmol/L [25]. As in Choudhary’s research, our study established 200 mmol/L NaCl as the baseline concentration for the screening of 165 eggplant germplasms, based on an SSI regression analysis showing ~50% physiological impairment across ten traits (Figure 1).
The significant correlations among STI values (Figure 2) underscore the overlapping biological responses to salinity, invalidating single-trait evaluations [17,35]. For example, Tian linked rice salt tolerance to the relative shoot/root length, germination vigor, and vitality index (r > 0.7), reducing seven traits to three principal components (91.6% variance) for classification into four tolerance tiers [36]. Similarly, Chunthaburee condensed 12 rice traits into two principal components (72.04% variance) to categorize germplasms [37]. In this study, PCA reduced 13 seedling-stage traits to seven principal components (cumulative variance > 80%; Table 5), with root architecture factors (RSA, RL, RV, RTN) dominating PC1 (24.8% variance). A weighted membership function analysis yielded D values, enabling the classification of the 165 germplasms into five groups: highly tolerant (6), tolerant (35), moderately tolerant (67), sensitive (49), and highly sensitive (8) (Figure 3, Table 6).
Identifying key diagnostic traits simplifies screening protocols and reduces the costs. While the stem biomass, Na+/K+ ratio, and RDW are established indicators in alfalfa and cotton [6,38], eggplant-specific markers remain underexplored. Our stepwise regression model isolated five critical predictors: RSA, LN, LWC, MDA, and SWC. This model explained 90.1% of the variance (r2 = 0.901), with 90.02% prediction accuracy (Figure 5), validating its utility for rapid, cost-effective eggplant salt tolerance screening.

5. Conclusions

In this study, 200 mmol/L was identified as the baseline for NaCl stress treatment in eggplant seedlings. A total of 13 traits were analyzed for 165 germplasms, and the traits showed different levels of sensitivity to salinity. A correlation analysis grouped these 13 traits into three clusters, and the strongest correlations occurred between RL and RSA. The 165 germplasms were classified into five distinct categories: six were highly salt-tolerant (HST), 35 were salt-tolerant (ST), 67 were moderately salt-tolerant (MST), 49 were salt-sensitive (SS), and eight were highly salt-sensitive (HSS). A predictive model for seedling-stage salt tolerance was developed, incorporating five key indicators: RSA, LN, LWC, MDA, and SWC. The model achieved 90.02% prediction accuracy (r2 = 0.901). These findings provide a reliable framework for the evaluation of salt tolerance in eggplant germplasm.

Author Contributions

This manuscript was written by Y.F., who completed the experimental design and data analysis. Z.W., Y.D., S.D. and Z.G. were involved in data collection and photo acquisition. S.L., Q.L. and X.C. conceived the original screening and research plans; S.L. and Q.L. supervised the experiments; and W.Z. and L.S. helped to harvest the eggplant germplasm. All authors have read and agreed to the published version of the manuscript.

Funding

We appreciate the financial support provided by the “S&T Program of Hebei” (23327501D).

Data Availability Statement

The raw data supporting the conclusions of this article will be made available by the authors upon request.

Conflicts of Interest

The authors declare that they have no competing interest.

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Figure 1. Determination of the optimal sodium chloride concentration for the evaluation of salt tolerance. (A) SSI of plant height (PH), (B) SSI of leaf number (LN), (C) SSI of leaf surface area (LSA), (D) SSI of root length (RL), (E) SSI of root fresh weight (RFW), (F) SSI of root dry weight (RDW), (G) SSI of stem fresh weight (SFW), (H) SSI of stem dry weight (SDW), (I) SSI of leaf fresh weight (LFW), (J) SSI of leaf dry weight (LDW).
Figure 1. Determination of the optimal sodium chloride concentration for the evaluation of salt tolerance. (A) SSI of plant height (PH), (B) SSI of leaf number (LN), (C) SSI of leaf surface area (LSA), (D) SSI of root length (RL), (E) SSI of root fresh weight (RFW), (F) SSI of root dry weight (RDW), (G) SSI of stem fresh weight (SFW), (H) SSI of stem dry weight (SDW), (I) SSI of leaf fresh weight (LFW), (J) SSI of leaf dry weight (LDW).
Horticulturae 11 00697 g001
Figure 2. Correlation heat map of 13 indices of salt tolerance index. * indicates significant differences at the 0.05 level; ** indicates significant differences at the 0.01 level.
Figure 2. Correlation heat map of 13 indices of salt tolerance index. * indicates significant differences at the 0.05 level; ** indicates significant differences at the 0.01 level.
Horticulturae 11 00697 g002
Figure 3. Cluster analysis of salt tolerance of 165 eggplant germplasms; (I) highly salt-tolerant germplasm; (II) salt-tolerant germplasm; (III) moderately salt-tolerant germplasm; (IV) salt-sensitive germplasm; (V) highly salt-sensitive germplasm.
Figure 3. Cluster analysis of salt tolerance of 165 eggplant germplasms; (I) highly salt-tolerant germplasm; (II) salt-tolerant germplasm; (III) moderately salt-tolerant germplasm; (IV) salt-sensitive germplasm; (V) highly salt-sensitive germplasm.
Horticulturae 11 00697 g003
Figure 4. Representative eggplant materials with different salt tolerances. Bar = 5 cm. (A) Highly salt-tolerant germplasm; (B) highly salt-sensitive germplasm.
Figure 4. Representative eggplant materials with different salt tolerances. Bar = 5 cm. (A) Highly salt-tolerant germplasm; (B) highly salt-sensitive germplasm.
Horticulturae 11 00697 g004
Figure 5. Linear fit of the predicted value D (F) to the true value D (T).
Figure 5. Linear fit of the predicted value D (F) to the true value D (T).
Horticulturae 11 00697 g005
Table 1. Information of 57 commercial germplasms.
Table 1. Information of 57 commercial germplasms.
SequenceNumberVariety NameSource
124QX2Shenqie twoShenyang Fengnong Agriculture
224QX3Shenqie oneShenyang Fengnong Agriculture
324QX4HeibawangShenyang Fengnong Agriculture
424QX5HuakuiShenyang Jinming Hang Agricultural Technology
524QX6JinmingchangShenyang Jinming Hang Agricultural Technology
624QX7DaguolvShenyang Jinming Hang Agricultural Technology
724QX8ZiyueJinan Tianren Seed
824QX9YuanqieguanjunJinan Tianren Seed
924QX10JindunlvguanXi’an Kington Seed Technology
1024QX11New dahongbaoXi’an Kington Seed Technology
1124QX12ZixianqieShenyang Fengnong Agriculture
1224QX13Yuanqie307Unknown
1324QX14YuanqieheiqiangUnknown
1424QX15YuanqieheijieUnknown
1524QX16Gaoke189Unknown
1624QX18Zihong twoUnknown
1724QX19Zihong threeUnknown
1824QX20Zihong fourUnknown
1924QX21Zihong fiveUnknown
2024QX22Lvqie oneUnknown
2124QX24NanhanheijiaolongXi’an Hangfeng Seed Industry
2224QX25ChangjiangzilongXi’an Hangfeng Seed Industry
2324QX26BaimawangziXi’an Hangfeng Seed Industry
2424QX27NanhanbaiyuqieXi’an Hangfeng Seed Industry
2524QX28HeipangziXi’an Hangfeng Seed Industry
2624QX29Meijiaozi sixXi’an Hangfeng Seed Industry
2724QX30ZhusiqieXi’an Hangfeng Seed Industry
2824QX31Zirong sixGuangdong Gannong Agricultural Technology
2924QX32MeiguiGuangdong Gannong Agricultural Technology
3024QX33Zirong eightGuangdong Gannong Agricultural Technology
3124QX34FeicuiGuangdong Gannong Agricultural Technology
3224QX35A116Unknown
3324QX36LaolunsiBeijing Zhongnong Kunchuang Seed
3424QX37AGC6317Unknown
3524QX38FengyuanheichangieXi’an Golden Seed Fengyuan Seed Industry
3624QX39FengyuandaminqieXi’an Golden Seed Fengyuan Seed Industry
3724QX40FengyuankuaiqieXi’an Golden Seed Fengyuan Seed Industry
3824QX41FengyuanlvguanqieXi’an Golden Seed Fengyuan Seed Industry
3924QX42FengyuanziguanXi’an Golden Seed Fengyuan Seed Industry
4024QX43FengyuanziyuanqieXi’an Golden Seed Fengyuan Seed Industry
4124QX44CaoqingqieHenan Dazheng Runhe Seed Industry
4224QX45Bailong332Fangzhen Agriculture
4324QX47Hangqie oneShouguang Xinxinran Horticulture
4424QX48Heibao twoShouguang Xinxinran Horticulture
4524QX49FenyanhuaShouguang Xinxinran Horticulture
4624QX51ZidaichangqieShouguang Xinxinran Horticulture
4724QX52GuangshenxianqieShouguang Xinxinran Horticulture
4824QX54HeiliangzaiJing Yan Yi Agricultural Seed Technology
4924QX55YuhangShouguang Xinxinran Horticulture
5024QX58ZiliXi’an Jinsheng Seed Industry
5124QX59JingqieheibaJing Yan Yi Agricultural Seed Technology
5224QX60Jingqie130Jing Yan Yi Agricultural Seed Technology
5324QX62RongyaochangqieShouguang Jinpeng Seed
5424QX63Nongda601Hebei Agricultural University
5524QX64Nongda604Hebei Agricultural University
5624QX67Nongda702Hebei Agricultural University
5724QX68Nongda703Hebei Agricultural University
Table 2. Information of 108 natural population germplasms.
Table 2. Information of 108 natural population germplasms.
SequenceVariety NameSourceSequenceVariety NameSource
124-477China5521C158France
224-479China5621C161United States of America
314-345China5721C162United States of America
416-562China5821C164India
5SanyueChina5921C170China
6HQ1315China6021C171China
721C1Turkey6121C172China
821C4Russian Federation6221C175India
921C6India6321C180China
1021C9United Kingdom6421C181Union of Soviet Soc. Rep.
1121C12India6521C185Unknown
1221C13Union of Soviet Soc. Rep.6621C186Italy
1321C19India6721C188Ukraine
1421C21Turkey6821C198China
1521C26Netherlands6921C199Unknown
1621C28Japan7021C204Turkey
1721C29Turkey7121C205Turkey
1821C32Unknown7221C207Turkey
1921C34Unknown7321C211Turkey
2021C35United Kingdom7421C214Turkey
2121C37Turkey7521C216Turkey
2221C38Turkey7621C217Turkey
2321C41Germany7721C218Turkey
2421C43Japan7821C219Turkey
2521C44Nepal7921C220Turkey
2621C45India8021C221Turkey
2721C46India8121C222Turkey
2821C48Malaysia8221C226Japan
2921C50India8321C228United States of America
3021C51Japan8421C229United States of America
3121C57Unknown8521C230Japan
3221C60India8621C234India
3321C61United States of America8721C236China
3421C64India8821C241Iran (Islamic Republic of)
3521C68Turkey8921C242Iran (Islamic Republic of)
3621C90Turkey9021C243India
3721C91Spain9121C245India
3821C95Turkey9221C247India
3921C104Japan9321C249Turkey
4021C105Japan9421C250Turkey
4121C107India9521C252China
4221C108China9621C280Maldives
4321C111Hungary9721C288Ukraine
4421C126India9821C291Syrian Arab Republic
4521C127India9921C293Syrian Arab Republic
4621C132China10021C301China
4721C135Iran (Islamic Republic of)10121C302China
4821C139India10221C305China
4921C141India10321C307China
5021C144Turkey10421C316China
5121C147Turkey10521C317China
5221C148Turkey10621C323China
5321C154India10721C331China
5421C155Unknown10821C336China
Table 3. Analysis of 13 indices of the salt tolerance index.
Table 3. Analysis of 13 indices of the salt tolerance index.
TraitMaximum ValueMinimum ValueAverage ValueStandard DeviationCoefficient of Variation
PH0.74 0.24 0.456 0.092 20.12%
SD0.73 0.34 0.492 0.079 15.96%
Chl1.73 0.79 1.261 0.143 11.32%
LN0.79 0.33 0.546 0.090 16.45%
LSA0.76 0.09 0.234 0.116 49.44%
RWC1.28 0.72 0.961 0.045 4.67%
SWC1.09 0.59 0.880 0.065 7.38%
LWC1.10 0.71 0.934 0.058 6.17%
MDA2.23 0.35 1.030 0.404 39.28%
RL2.05 0.25 0.663 0.220 33.16%
RTN4.12 0.21 0.968 0.424 43.80%
RSA1.61 0.12 0.504 0.216 42.79%
RV0.89 0.06 0.415 0.188 45.25%
Table 4. KMO and Bartlett ball tests for 13 indices of salt tolerance index.
Table 4. KMO and Bartlett ball tests for 13 indices of salt tolerance index.
KMO and Bartlett Ball Tests
Kaiser–Meyer–Olkin sampling adequacy measurement 0.644
Approx. chi-squared807.515
Bartlett ball testdf78
sig0.00
Table 5. Principal component analysis of 13 indices of salt tolerance index.
Table 5. Principal component analysis of 13 indices of salt tolerance index.
TraitPrincipal Component
1234567
RSA0.9630.076−0.022−0.024−0.0010.0010.062
RL0.9180.0260.069−0.1790.008−0.1150.162
RV0.8920.172−0.1070.0690.0260.149−0.1
RTN0.551−0.0420.407−0.277−0.386−0.0670.34
LSA0.1420.762−0.04−0.0940.170.1130.225
PH0.0010.680.318−0.0240.106−0.2940.04
SD0.2820.577−0.464−0.085−0.030.304−0.12
LN0.0200.1320.8130.2080.0310.165−0.175
MDA−0.108−0.1230.150.909−0.0240.073−0.006
LWC0.0070.2720.0980.020.813−0.0330.084
RWC0.0030.450.2040.406−0.538−0.055−0.03
Chl−0.006−0.0110.10.066−0.0010.9360.042
SWC0.0960.156−0.12−0.0010.0830.040.925
Eigenvalue2.991.7461.2591.171.1491.1461.119
Contribution rate22.99813.4329.6889.0008.8398.8168.606
Cumulative contribution rate22.99836.43046.11855.11863.95672.77281.378
Table 6. Membership function analysis of eggplant comprehensive index and comprehensive evaluation of 165 materials.
Table 6. Membership function analysis of eggplant comprehensive index and comprehensive evaluation of 165 materials.
Variety
Name
Comprehensive IndexMembership Function ValueD ValueRank
PCA1PCA2PCA3PCA4PCA5PCA6PCA7UX1UX2UX3UX4UX5UX6UX7
24QX2−0.0250.2141.5291.026−0.2221.357−0.2770.2740.4590.7790.6470.4090.7500.5280.49920
24QX3−0.1570.652−0.6391.158−0.4370.6450.2250.2530.5210.3570.6720.3810.6440.6000.44950
24QX4−0.9150.3870.4660.225−0.490−0.206−0.4870.1370.4830.5720.4950.3740.5180.4980.391115
24QX5−0.1850.518−0.1690.038−0.238−0.357−0.7880.2490.5020.4480.4590.4070.4950.4540.404105
24QX6−0.6500.0890.7860.835−0.255−0.783−0.0560.1780.4420.6340.6100.4050.4320.5600.41791
24QX7−0.948−0.3791.685−0.2650.484−0.208−0.3870.1320.3760.8090.4020.5020.5180.5120.405103
24QX80.162−0.2391.8341.7580.3310.4600.2060.3020.3960.8380.7850.4820.6170.5970.52012
24QX91.4791.0911.2631.1500.1502.189−0.1920.5040.5820.7270.6700.4580.8740.5400.6011
24QX10−1.338−0.5672.1840.194−0.0421.6000.4030.0730.3500.9070.4890.4330.7860.6260.43961
24QX11−0.312−0.0940.6161.0590.0600.988−0.4980.2300.4160.6010.6530.4470.6950.4960.45445
24QX12−0.118−0.9580.6382.3190.2931.307−0.1620.2590.2950.6050.8920.4770.7430.5450.48331
24QX130.930−0.0121.0040.0600.2050.440−2.9250.4200.4280.6770.4640.4660.6140.1470.45446
24QX140.7390.092−0.0551.6160.0880.755−0.0800.3910.4420.4700.7590.4500.6610.5560.50319
24QX150.094−0.037−0.4021.3980.2672.715−0.1270.2920.4240.4030.7170.4740.9510.5490.49324
24QX16−1.1250.4290.8640.475−0.2960.832−0.1780.1050.4890.6490.5420.4000.6720.5420.42279
24QX18−1.400−0.4431.5832.103−0.0090.5070.2500.0630.3670.7890.8510.4370.6240.6040.44654
24QX190.445−1.2712.2320.3900.9090.622−0.6860.3460.2520.9160.5260.5580.6410.4690.48728
24QX200.066−0.0501.038−0.140−0.448−0.785−0.5350.2870.4220.6830.4260.3800.4320.4910.42087
24QX211.0110.131−0.1841.426−1.203−1.108−0.7020.4320.4480.4450.7220.2800.3840.4670.45148
24QX22−0.912−0.6961.507−0.193−0.8900.158−0.3250.1380.3320.7750.4160.3210.5720.5210.384124
24QX24−0.6320.0731.352−0.027−0.428−0.1230.2690.1810.4400.7450.4470.3820.5300.6070.42575
24QX25−0.158−0.6930.059−0.071−0.124−0.869−0.8550.2530.3320.4930.4390.4220.4200.4450.372133
24QX261.1991.4350.431−0.602−0.7900.677−1.5160.4610.6300.5650.3380.3350.6490.3500.48332
24QX27−0.312−0.289−0.4620.040−0.2900.807−0.8060.2300.3890.3910.4600.4000.6680.4520.390117
24QX280.131−0.5051.324−0.161−0.6630.698−0.4290.2970.3590.7390.4220.3510.6520.5060.44060
24QX290.0330.202−0.9470.758−0.2260.838−1.6970.2820.4580.2970.5960.4090.6730.3230.40899
24QX30−0.170−0.9410.918−0.7650.6120.319−2.8580.2510.2980.6600.3070.5190.5960.1560.370135
24QX31−1.086−0.3270.4480.807−0.680−1.020−1.5550.1110.3840.5680.6050.3490.3970.3440.347154
24QX32−0.753−0.3620.416−0.480−0.216−0.457−2.6760.1620.3790.5620.3610.4100.4810.1830.331156
24QX330.4300.4561.4520.316−0.751−1.374−0.7970.3430.4930.7640.5120.3400.3450.4530.44951
24QX34−0.764−0.8191.1420.9400.1850.697−0.7950.1600.3150.7030.6300.4630.6520.4530.42085
24QX35−0.307−0.5060.5880.015−0.380−0.538−0.7210.2300.3590.5960.4550.3890.4690.4640.388120
24QX36−1.0130.5930.0610.700−0.698−0.880−0.5590.1220.5120.4930.5850.3470.4180.4870.377131
24QX37−0.995−0.480−0.1761.736−0.091−1.197−0.1970.1250.3620.4470.7810.4270.3710.5390.379129
24QX38−0.133−0.2840.4841.6680.051−0.835−0.7540.2570.3900.5750.7680.4450.4250.4590.43465
24QX391.3540.3010.7230.203−0.146−0.464−1.5970.4850.4710.6220.4910.4190.4800.3380.47734
24QX40−0.715−1.4051.5051.2670.8540.7690.1840.1680.2330.7740.6920.5510.6630.5940.45049
24QX41−1.702−0.4901.6881.4120.494−0.1390.4810.0170.3610.8100.7200.5040.5280.6370.42084
24QX42−0.1960.3780.8300.6780.2540.3260.1320.2470.4820.6430.5810.4720.5970.5870.46939
24QX43−0.105−0.6681.4711.2710.651−0.8370.3940.2610.3360.7680.6930.5240.4240.6250.46740
24QX44−0.557−0.2350.4780.667−0.024−1.3690.6190.1920.3970.5740.5790.4350.3450.6570.407100
24QX450.631−1.0520.2832.6070.0870.5130.0280.3740.2820.5360.9460.4500.6250.5720.49821
24QX470.209−0.709−0.2772.3740.1091.2580.4470.3090.3300.4270.9020.4530.7350.6320.48927
24QX48−0.3340.297−0.6450.8580.090−0.998−0.2550.2260.4710.3550.6150.4500.4000.5310.401108
24QX490.509−0.353−1.2740.845−0.2293.0420.2460.3550.3800.2330.6130.4081.0000.6030.47535
24QX51−0.5860.809−0.2200.066−1.1070.4530.6030.1880.5430.4380.4650.2930.6160.6550.41493
24QX520.927−0.249−0.6870.3850.4110.046−0.0600.4190.3950.3470.5250.4930.5550.5590.45644
24QX54−1.216−1.128−0.0900.4980.764−0.6570.9360.0910.2720.4630.5470.5390.4510.7030.368138
24QX55−0.519−0.7930.0980.864−0.862−0.3980.8570.1980.3180.5000.6160.3250.4890.6910.398109
24QX58−0.1700.3910.1012.184−1.933−0.531−0.0930.2510.4840.5010.8660.1840.4700.5540.43662
24QX59−1.0140.960−0.1901.219−0.658−0.1890.7790.1220.5640.4440.6830.3520.5200.6800.42378
24QX600.024−0.212−0.0911.196−1.2540.022−1.2850.2810.4000.4630.6790.2730.5520.3830.406102
24QX620.7460.3910.092−0.204−2.214−0.295−1.3370.3920.4840.4990.4140.1470.5050.3750.406101
24QX63−0.646−1.055−1.1351.107−1.9800.5741.1840.1790.2820.2600.6620.1780.6340.7380.367141
24QX641.119−0.6880.5182.890−1.388−0.8271.3010.4490.3330.5821.0000.2560.4260.7550.51613
24QX67−0.955−0.171−1.2170.100−0.9880.4411.2900.1310.4050.2440.4710.3080.6140.7540.365143
24QX68−0.814−0.380−0.504−0.215−0.7590.1260.2370.1530.3760.3830.4120.3380.5670.6020.358145
24-477−0.557−0.4551.5490.0250.426−0.293−0.3810.1920.3660.7830.4570.4950.5050.5130.42182
24-479−0.339−1.0730.081−0.3140.673−1.223−1.6110.2250.2790.4970.3930.5270.3670.3360.345155
14-3450.470−0.510−0.5490.7510.059−0.088−1.0400.3490.3580.3740.5950.4460.5350.4180.41988
16-5621.6380.916−0.1270.657−0.3050.195−1.1180.5280.5570.4560.5770.3980.5770.4070.50916
Sanyue−0.747−0.910−0.725−1.861−3.3280.545−0.3200.1630.3020.3400.1000.0000.6290.5220.271164
HQ1315−0.284−0.3090.078−1.252−1.287−0.139−0.6550.2340.3860.4960.2150.2690.5280.4740.349151
21C1−0.4881.621−1.616−0.488−0.3880.9540.0670.2030.6560.1660.3600.3870.6900.5770.403106
21C4−1.600−0.3010.554−1.361−0.010−2.174−1.1050.0320.3870.5890.1940.4370.2260.4090.280161
21C60.826−0.111−2.469−0.841−0.4211.434−1.0070.4040.4140.0000.2930.3830.7610.4230.384125
21C90.165−0.262−0.660−0.977−0.395−1.295−2.1320.3030.3930.3520.2670.3860.3560.2610.330157
21C121.046−1.0841.074−1.029−0.5841.242−2.1000.4380.2780.6900.2570.3620.7330.2660.42772
21C13−0.9121.4001.355−1.439−0.3450.742−0.2790.1380.6250.7450.1800.3930.6590.5280.42183
21C19−1.053−0.162−0.275−0.2880.4961.0331.2310.1160.4070.4270.3980.5040.7020.7450.405104
21C21−0.141−0.180−0.112−0.4710.0600.6600.0690.2560.4040.4590.3630.4460.6470.5780.41494
21C26−0.010−0.119−0.808−0.598−0.294−1.0660.6920.2760.4130.3240.3390.4000.3900.6670.379128
21C28−0.1280.044−0.951−0.456−0.7110.698−0.1820.2580.4350.2960.3660.3450.6520.5420.386122
21C29−0.5530.674−0.532−1.066−0.6930.815−0.1420.1930.5240.3770.2500.3470.6700.5470.382127
21C321.575−0.660−0.7280.282−0.6440.639−0.0640.5190.3370.3390.5060.3540.6430.5590.46641
21C34−0.618−0.061−0.515−0.167−0.4420.0580.8040.1830.4210.3810.4210.3800.5570.6840.387121
21C350.860−0.711−0.247−1.131−0.0140.0300.6660.4090.3300.4330.2380.4370.5530.6640.42673
21C372.1341.015−0.077−1.0240.2920.850−0.1750.6040.5710.4660.2580.4770.6750.5430.5329
21C383.2790.519−0.471−0.294−0.882−1.6970.5620.7790.5020.3890.3970.3220.2970.6490.53010
21C41−1.2690.271−0.429−1.290−1.1891.786−0.1080.0830.4670.3970.2080.2820.8140.5520.348152
21C43−1.812−0.333−1.158−0.727−1.7170.1770.2590.0000.3830.2550.3150.2120.5750.6050.278163
21C44−1.775−1.4150.270−1.4070.497−0.6840.5930.0060.2310.5340.1860.5040.4470.6530.296160
21C45−0.690−0.863−1.566−0.5800.565−0.710−0.8170.1720.3090.1760.3420.5130.4430.4500.310158
21C46−1.214−0.4650.245−0.670−0.5651.944−0.2140.0910.3640.5290.3250.3640.8370.5370.372134
21C480.8490.4320.174−0.943−1.297−0.981−0.7890.4070.4900.5150.2740.2680.4030.4540.40998
21C500.6920.648−1.893−0.252−0.1691.785−0.3410.3830.5200.1120.4050.4160.8140.5190.44159
21C51−0.3350.244−1.210−0.906−0.6891.079−0.5130.2260.4630.2450.2810.3480.7090.4940.368140
21C570.485−1.6410.349−0.552−1.8360.1521.0630.3520.2000.5490.3480.1970.5710.7210.396110
21C60−1.5070.252−1.726−0.101−2.653−3.6950.7430.0470.4650.1450.4330.0890.0000.6750.236165
21C61−0.7030.1260.292−0.3140.0790.0361.5210.1700.4470.5380.3930.4490.5540.7870.42281
21C64−0.1910.5020.433−0.2150.644−0.803−0.7090.2480.5000.5650.4120.5230.4290.4660.41889
21C681.279−0.825−0.4660.2000.171−0.9140.2950.4730.3140.3900.4900.4610.4130.6100.44653
21C900.8140.116−0.176−0.605−0.060−1.149−0.1420.4020.4460.4470.3380.4310.3780.5470.42476
21C910.6390.0921.532−0.5490.7000.6670.4600.3750.4420.7800.3480.5310.6480.6340.50618
21C950.3470.9660.1481.2610.8280.3210.4510.3310.5640.5100.6910.5480.5960.6330.51514
21C1040.300−1.730−0.760−1.1321.8560.0860.1350.3230.1870.3330.2380.6830.5610.5870.386123
21C1050.695−2.1400.457−0.7551.5630.2940.1170.3840.1300.5700.3090.6450.5920.5850.42869
21C1070.2541.002−0.557−0.9160.1940.8260.2150.3160.5690.3720.2790.4640.6710.5990.44556
21C108−1.153−0.6800.918−1.3480.0960.4800.6400.1010.3340.6600.1970.4510.6200.6600.370136
21C111−1.059−0.4800.776−1.0530.8610.6230.6330.1150.3620.6320.2530.5520.6410.6590.395111
21C1260.6560.6710.710−1.2820.461−1.478−0.2860.3780.5230.6190.2090.4990.3290.5270.43663
21C1270.0960.4890.506−0.9660.914−0.301−0.3360.2920.4980.5800.2690.5590.5040.5190.43464
21C132−0.304−0.076−1.310−0.3190.204−1.8480.1310.2310.4190.2260.3920.4660.2740.5870.347153
21C1350.1760.107−0.936−0.251−0.0482.327−0.8400.3040.4440.2990.4050.4320.8940.4470.43166
21C1390.171−0.845−0.839−0.788−0.105−0.1240.2480.3040.3110.3170.3030.4250.5300.6030.376132
21C141−0.5601.244−0.327−1.044−0.6440.611−0.4640.1920.6030.4170.2540.3540.6390.5010.392114
21C144−0.4761.307−0.310−0.2390.7930.3950.4200.2050.6120.4210.4070.5430.6070.6280.44555
21C147−0.814−2.426−0.077−1.9444.2600.5280.0380.1530.0900.4660.0841.0000.6270.5730.360144
21C1481.504−0.3560.3350.3511.418−0.0490.5480.5080.3800.5460.5190.6250.5410.6470.52411
21C154−0.603−0.226−1.0650.0931.2420.0951.4480.1850.3980.2730.4700.6020.5630.7760.41197
21C155−0.178−0.997−0.130−1.0912.555−0.723−0.1120.2500.2900.4560.2460.7750.4410.5520.391116
21C158−0.506−0.429−0.110−0.8400.7741.4080.7420.2000.3690.4600.2930.5410.7570.6750.41790
21C1610.198−1.0270.6330.4370.426−0.1290.9450.3080.2860.6040.5350.4950.5290.7040.45147
21C162−0.080−0.460−1.531−0.303−0.2590.0080.8530.2650.3650.1830.3950.4040.5500.6910.377130
21C164−1.027−0.944−0.135−1.091−0.477−0.0811.9760.1200.2970.4550.2460.3760.5370.8520.354148
21C170−0.5460.3320.805−1.232−1.2700.5821.3770.1940.4760.6380.2190.2710.6350.7660.41395
21C1710.279−1.546−0.754−0.161−2.0141.1681.2530.3200.2130.3340.4220.1730.7220.7480.388119
21C172−0.087−0.686−0.847−1.023−1.9700.4180.7830.2640.3330.3160.2580.1790.6110.6810.354149
21C1751.390−0.1510.192−0.929−0.8260.658−0.4900.4900.4080.5180.2760.3300.6460.4970.45743
21C180−1.219−0.3960.207−0.978−0.490−0.0780.9430.0910.3740.5210.2670.3740.5370.7040.352150
21C1810.361−0.739−0.8330.238−0.8690.8810.7640.3330.3260.3190.4970.3240.6790.6780.42280
21C1850.467−1.840−1.3922.246−0.006−0.8140.7200.3490.1720.2100.8780.4380.4280.6710.41592
21C1863.769−2.4410.9450.532−1.2000.1911.4180.8540.0880.6650.5530.2800.5770.7720.5724
21C1884.719−3.0702.664−2.387−1.208−2.7682.3801.0000.0001.0000.0000.2790.1380.9100.5447
21C198−0.398−0.808−0.057−0.9640.058−0.459−3.9440.2160.3160.4700.2700.4460.4800.0000.300159
21C199−0.134−1.406−2.103−0.049−0.0551.0410.2520.2570.2330.0710.4430.4310.7030.6040.356147
21C2040.263−0.786−0.870−0.8230.408−0.585−0.4520.3180.3190.3110.2960.4920.4620.5030.369137
21C2050.376−0.447−1.127−0.2171.051−1.473−2.1370.3350.3670.2610.4110.5770.3300.2600.358146
21C207−0.061−0.506−1.4061.2540.098−0.089−0.9490.2680.3590.2070.6900.4510.5350.4310.389118
21C211−0.295−1.038−0.5600.5040.9200.056−1.1160.2320.2840.3720.5480.5600.5570.4070.382126
21C214−1.014−0.751−1.991−0.4790.612−1.166−1.0890.1220.3240.0930.3620.5190.3760.4110.280162
21C216−0.5420.981−0.6310.4271.194−0.589−0.1410.1940.5660.3580.5330.5960.4610.5480.42377
21C2170.079−0.184−1.8011.4971.045−1.0630.5830.2900.4040.1300.7360.5760.3910.6520.42086
21C218−0.617−0.091−1.5040.4401.639−1.7430.1820.1830.4170.1880.5360.6550.2900.5940.368139
21C2190.7611.908−1.7900.4481.3710.895−0.6290.3940.6960.1320.5370.6190.6810.4770.49323
21C220−0.069−0.192−0.6960.7381.855−1.8801.0360.2670.4020.3450.5920.6830.2690.7170.42870
21C221−1.2070.524−0.5930.8021.815−1.2610.6120.0930.5030.3650.6040.6780.3610.6560.402107
21C2222.0121.522−1.0121.8562.6120.031−0.4540.5850.6420.2840.8040.7830.5530.5030.5932
21C226−0.5930.8610.0400.4442.021−1.1130.5370.1870.5500.4890.5360.7050.3830.6450.44852
21C228−0.2801.188−0.2580.6780.830−0.5880.6160.2350.5950.4310.5810.5480.4610.6570.45942
21C229−0.2230.225−0.137−0.3740.400−0.0430.7670.2430.4610.4540.3810.4910.5420.6780.42574
21C2300.5411.709−0.238−0.6030.032−0.710−2.9450.3600.6680.4350.3380.4430.4430.1440.41396
21C234−0.1011.284−1.158−0.6690.475−0.1781.1660.2620.6090.2550.3250.5010.5220.7360.43067
21C2360.070−0.7380.030−0.942−0.146−0.9451.2680.2880.3260.4870.2740.4190.4080.7500.393113
21C2411.3592.4102.640−1.4190.161−0.6500.0080.4860.7660.9950.1830.4600.4520.5690.5625
21C2422.2682.183−1.014−0.7410.6570.0490.6760.6250.7350.2830.3120.5250.5560.6650.5546
21C2430.1112.005−0.5710.4420.435−0.3090.7160.2940.7100.3700.5360.4960.5030.6710.48330
21C2450.5600.791−0.239−0.8170.0430.4883.0020.3630.5400.4340.2970.4440.6211.0000.49822
21C2470.3661.0880.391−0.4140.0870.8010.1130.3330.5820.5570.3740.4500.6670.5840.48133
21C2490.1031.2220.533−0.3110.128−0.0280.3560.2930.6000.5850.3930.4550.5440.6190.46938
21C250−0.0601.044−0.875−0.550−0.0230.7791.1480.2680.5750.3100.3480.4360.6640.7330.44357
21C2521.4730.360−0.500−0.8090.7030.3250.4790.5030.4800.3840.2990.5310.5970.6370.49026
21C2800.7540.063−0.2330.2120.958−0.0160.9620.3930.4380.4360.4920.5650.5460.7060.48529
21C2880.9241.8520.006−0.7620.182−0.3451.1550.4190.6880.4820.3080.4630.4970.7340.50617
21C2911.452−0.297−1.1800.0220.7370.2810.1700.5000.3880.2510.4560.5360.5900.5920.47137
21C2932.4931.270−0.4950.2901.064−0.0430.4240.6590.6070.3850.5070.5790.5420.6290.5773
21C301−0.9121.8942.346−1.8690.8741.3600.9370.1380.6940.9380.0980.5540.7500.7030.49225
21C302−1.4101.7760.525−0.0551.440−0.1950.6370.0610.6780.5830.4420.6280.5200.6600.44258
21C3050.2331.8492.067−1.0490.9210.5620.7000.3130.6880.8840.2540.5600.6320.6690.5368
21C307−0.5074.0801.3682.107−2.553−2.2170.6650.2001.0000.7480.8520.1020.2190.6640.51015
21C3160.1050.935−1.045−0.4250.2590.520−0.0500.2930.5600.2770.3720.4730.6260.5610.42871
21C317−0.7841.5530.074−0.890−0.057−1.6090.7650.1570.6470.4950.2840.4310.3100.6780.394112
21C323−0.5520.2451.135−0.0361.2810.2371.2380.1930.4640.7020.4460.6070.5840.7460.47236
21C331−0.4850.9540.953−0.899−0.6950.2150.5480.2030.5630.6670.2820.3470.5800.6470.43068
21C336−0.9530.262−0.225−0.6030.417−1.2020.6300.1310.4660.4370.3380.4940.3700.6590.367142
Table 7. Classification of salt tolerance of 165 eggplant germplasms.
Table 7. Classification of salt tolerance of 165 eggplant germplasms.
Classification of Salt ToleranceVariety NameQuantity
Highly salt-tolerant (HST)24QX9, 21C222, 21C293, 21C186, 21C241, 21C2426
Salt-tolerant (ST)21C188, 21C305, 21C37, 21C38, 21C148, 24QX8, 24QX64, 21C95, 21C307, 16-562, 21C288, 21C91, 24QX14, 24QX2, 24QX45, 21C245, 21C219, 24QX15, 21C301, 21C252, 24QX47, 24QX19, 21C280, 21C243, 24QX12, 24QX26, 21C247, 24QX39, 24QX49, 21C323, 21C291, 21C249, 24QX42, 24QX43, 21C3235
Moderately salt-tolerant (MST)21C228, 21C175, 24QX52, 24QX11, 24QX13, 21C161, 24QX21, 24QX40, 24QX3, 24QX33, 21C226, 21C68, 24QX18, 21C144, 21C107, 21C250, 21C302, 21C50, 24QX28, 24QX10, 24QX58, 21C126, 21C127, 24QX38, 21C135, 21C234, 21C331, 21C105, 21C220, 21C316, 21C12, 21C35, 21C229, 24QX24, 21C90, 21C216, 24QX59, 24QX16, 21C181, 21C61, 24-477, 21C13, 24QX41, 24QX34, 21C217, 24QX20, 14-345, 21C64, 21C158, 24QX6, 21C185, 24QX51, 21C21, 21C170, 21C230, 21C154, 21C48, 24QX29, 24QX44, 24QX62, 24QX60, 24QX7, 21C19, 24QX5, 21C1, 21C221, 24QX4867
Salt-sensitive (SS)24QX55, 21C57, 21C111, 21C317, 21C236, 21C141, 24QX4, 21C155, 24QX27, 21C207, 21C171, 24QX35, 21C34, 21C28, 21C104, 24QX22, 21C6, 21C211, 21C29, 21C26, 24QX37, 21C162, 24QX36, 21C139, 24QX25, 21C46, 24QX30, 21C108, 21C204, 24QX54, 21C218, 21C51, 24QX63, 21C336, 24QX67, 21C147, 24QX68, 21C205, 21C199, 21C164, 21C172, 21C180, HQ1315, 21C41, 21C132, 24QX31, 24-479, 24QX32, 21C949
Highly salt-sensitive (HSS)21C45, 21C198, 21C44, 21C4, 21C214, 21C43, Sanyue, 21C608
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MDPI and ACS Style

Fang, Y.; Wang, Z.; Du, Y.; Di, S.; Gao, Z.; Chen, X.; Zhang, W.; Song, L.; Luo, S.; Li, Q. Comprehensive Evaluation and Screening for Salt Tolerance Germplasms at Seedling Stage in Eggplant. Horticulturae 2025, 11, 697. https://doi.org/10.3390/horticulturae11060697

AMA Style

Fang Y, Wang Z, Du Y, Di S, Gao Z, Chen X, Zhang W, Song L, Luo S, Li Q. Comprehensive Evaluation and Screening for Salt Tolerance Germplasms at Seedling Stage in Eggplant. Horticulturae. 2025; 11(6):697. https://doi.org/10.3390/horticulturae11060697

Chicago/Turabian Style

Fang, Yu, Zhiguo Wang, Yingnan Du, Shuaitao Di, Zhenwei Gao, Xueping Chen, Weiwei Zhang, Lijun Song, Shuangxia Luo, and Qiang Li. 2025. "Comprehensive Evaluation and Screening for Salt Tolerance Germplasms at Seedling Stage in Eggplant" Horticulturae 11, no. 6: 697. https://doi.org/10.3390/horticulturae11060697

APA Style

Fang, Y., Wang, Z., Du, Y., Di, S., Gao, Z., Chen, X., Zhang, W., Song, L., Luo, S., & Li, Q. (2025). Comprehensive Evaluation and Screening for Salt Tolerance Germplasms at Seedling Stage in Eggplant. Horticulturae, 11(6), 697. https://doi.org/10.3390/horticulturae11060697

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