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Article

Evaluating the Cold Tolerance of Stenotaphrum Trin Plants by Integrating Their Performance at Both Fall Dormancy and Spring Green-Up

by
Jia Qu
1,†,
Dong-Li Hao
2,†,
Jin-Yan Zhou
3,
Jing-Bo Chen
2,
Dao-Jin Sun
2,
Jian-Xiu Liu
2,
Jun-Qin Zong
2,* and
Zhi-Yong Wang
1,*
1
Sanya Nanfan Research Institute, College of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China
2
The National Forestry and Grassland Administration Engineering Research Center for Germplasm Innovation and Utilization of Warm-Season Turfgrasses, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences (Nanjing Botanical Garden Mem. Sun Yat-Sen), Nanjing 210014, China
3
Department of Agronomy and Horticulture, Jiangsu Vocational College of Agriculture and Forest, Jurong 212400, China
*
Authors to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Horticulturae 2024, 10(7), 761; https://doi.org/10.3390/horticulturae10070761
Submission received: 21 June 2024 / Revised: 14 July 2024 / Accepted: 16 July 2024 / Published: 18 July 2024
(This article belongs to the Special Issue Tolerance and Response of Ornamental Plants to Abiotic Stress)
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Abstract

:
Owing to the poor cold tolerance of Stenotaphrum Trin and the urgent need for shade-tolerant grass species in temperate regions of East China, this study evaluated the cold tolerance of 55 Stenotaphrum accessions, aiming to provide shade-tolerant materials for temperate regions. A fine cold-tolerant turfgrass should have both the advantages of delayed fall dormancy and early spring green-up. However, previous research on the cold resistance of turfgrass has mainly focused on the performance of the spring green-up, with less attention paid to the fall dormancy, which has affected the ornamental and application value of turfgrass. This study first dynamically investigated the leaf colour of each accession during the fall dormancy and the coverage during the spring green-up and evaluated the cold resistance of the accession through membership functions and cluster analysis. Significant differences in the cold resistance were found with the assignment of breeding lines to four categories. The weak correlation (R2 = 0.1682) between leaf colour during the fall dormancy and coverage during the spring green-up indicates that using the performance of a single period to represent the cold resistance of accessions is not appropriate. To test whether using the laboratory-based LT50 and stolon regrowth rating analysis can replace the above-improved method, we conducted a related analysis and found that the fit between these two methods is very poor. This phenomenon is attributed to the poor correlation between the laboratory-based parameters and the pot-investigated data. Therefore, this study presents a cold resistance evaluation method for Stenotaphrum that integrates performance in both the fall dormancy and spring green-up periods. This improved evaluation method cannot be simplified by the growth performance of a single period or replaced by using laboratory-based LT50 and stolon regrowth tests. With the help of this improved method, several excellent cold tolerance accessions (ST003, S13, and S12) were identified for temperate regions of East China.

1. Introduction

The tropical turfgrass Stenotaphrum Trin has both feed and ornamental value [1]. Due to its much greater shade tolerance than that of other warm-season turfgrasses, Stenotaphrum species are preferred for use in shaded landscapes in tropical and subtropical regions [2,3]. However, its poor cold tolerance severely restricts its use in temperate regions [4,5,6]. Given the need for shade-tolerant turfgrasses in the temperate regions of East China, the use of Stenotraphrum requires the identification and use of cold-resistant germplasm for acceptance and application by the public.
Unlike annual plants such as wheat that do not undergo the fall dormancy process, perennial turfgrass with strong cold resistance should have both the advantages of delayed fall dormancy and early spring green-up [7,8,9]. Field and laboratory evaluations are commonly used for evaluating cold resistance. Field evaluation is considered as a relatively accurate method of evaluating cold resistance. However, field evaluations mainly focus on the performance of green-up in the following year, with less attention paid to the performance of fall dormancy [10,11]. Electrolyte leakage and tissue regrowth measurements are common laboratory methods used to assess cold tolerance in turfgrass species [5,12,13]. Electrolyte leakage has been shown to poorly represent the actual cold tolerance [14,15,16]. Measurements of tissue regrowth have also been shown to be poorly correlated with cold resistance [4,17,18]. These methods are likely not reflective of actual cold tolerance because they do not account for a plant’s ability to retain colour in the fall or an ability to green-up earlier in the spring. Therefore, the objective of this research was to measure both fall dormancy and spring green-up to assess the cold tolerance of Stenotaphrum breeding lines and to compare this assessment to electrolyte leakage and stolon regrowth following exposure to cold.
Stenotaphrum plants can be divided into seven categories (https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:19069-1#source-KB, accessed on 20 June 2024). (1) Stenotaphrum helferi. the native range of this species is South China to Peninsula Malaysia, Philippines. It is a perennial or rhizomatous geophyte and grows primarily in the wet tropical biome. (2) Stenotaphrum clavigerum. The native range of this species is Aldabra to Assumption. It is an annual and grows primarily in the seasonally dry tropical biome. (3) Stenotaphrum dimidiatum. The native range of this species is coastal Kenya to South Africa, West Indian Ocean, and the Indian Subcontinent to Peninsula Malaysia. It is a perennial or rhizomatous geophyte and grows primarily in the seasonally dry tropical biome. (4) Stenotaphrum micranthum. The native range of this species is Southeast Tanzania to the West Indian Ocean, Spratly Islands, and East Malaysia to the Pacific Ocean. It is an annual and grows primarily in the seasonally dry tropical biome. (5) Stenotaphrum oostachyum. The native range of this species is Northwest and Central Madagascar. It is a perennial or rhizomatous geophyte and grows primarily in the seasonally dry tropical biome. (6) Stenotaphrum secundatum. The native range of this species is Southeast U.S.A. to eastern and southern South America and West Tropical Africa to Chad. It is a perennial or rhizomatous geophyte and grows primarily in the seasonally dry tropical biome. It is used as animal food and a medicine and has uses environmentally and for food. (7) Stenotaphrum unilaterale. The native range of this species is Central Madagascar. It is a perennial or rhizomatous geophyte and grows primarily in the seasonally dry tropical biome. The distribution of Stenotaphrum plants in China is mainly in South China. The use of which is also mainly in the tropical and subtropical regions of China. No dominant variety was found. Significant variations in cold tolerance among the species of Stenotaphrum plants [5,6] have been detected. Although the cold tolerance has been investigated on many accessions from Europe and North America [19,20,21,22], the large-scale cold tolerance evaluation of Stenotaphrum plants from China is still lacking. This notion is further supported by the finding that Stenotaphrum research undertaken by Chinese scholars mainly focuses on molecular maker analysis, physiology, and pathology, with little attention paid to the cold tolerance evaluation of Stenotaphrum plants from China [23,24,25,26,27,28,29,30]. This study used 55 accessions of Stenotaphrum plants, the composition of which was mainly wild accessions from China, aiming to establish a suitable cold tolerance evaluation method for Stenotaphrum plants and identify several accessions that can be applied to the temperate regions of East China.
Specifically, this study first dynamically investigated the leaf colour during the fall dormancy and the coverage during the spring green-up of 55 Stenotaphrum Trin resources and evaluated their cold resistance by integrating the two-index using a membership function. By analysing the correlation between autumn/winter leaf colour and next year’s green-up coverage, as well as comparing the growth performance of a single growth period with the ranking of a comprehensive evaluation, whether this method can be simplified by the growth performance of the fall dormancy or spring green-up is clarified. Furthermore, the cold resistance of these resources was evaluated through the laboratory-based cold resistance evaluation methods (leaf LT50 and stolon regrowth analysis) and was ranked and clustered through membership functions and cluster analysis. Whether field evaluation methods can be replaced by laboratory evaluation methods was determined by comparing the differences between laboratory cold resistance evaluation data and field evaluation data. By conducting a correlation analysis between field evaluation data and laboratory evaluation data, the reasons for the differences between field evaluation and laboratory evaluation were clarified. Through the above series of experiments, this study ultimately presented a method to compensate for the shortcomings of the current evaluation methods for the cold resistance of turfgrass and clarified whether this improved method can be simplified or replaced by other methods.

2. Materials and Methods

2.1. Accession Information

Eighty domestic and foreign accessions of Stenotaphrum were collected for cold tolerance evaluation. These accessions came from China (63), the United States (10), South Africa (3), Zimbabwe (1), Australia (1), Argentina (1), and Vanuatu (1). At one year of planting in Nanjing, China, only 55 accessions had survived, i.e., 25 accessions did not survive the winter. Among the 55 surviving accessions, 41 were sourced from China, 8 from the United States, 2 from South Africa, 1 from Zimbabwe, 1 from Australia, 1 from Argentina, and 1 from Vanuatu (Supplementary Table S1). Specifically in China, the strains were obtained from Fujian Province (14), Hainan Province (14), Yunnan Province (5), Guangxi Province (5), and Guangdong Province (3) and conformed to the distribution characteristics of Stenotaphrum (https://www.iplant.cn/z/frps/33150, accessed on 15 June 2024). Subsequently, the cold resistance of these 55 accessions was evaluated.

2.2. Plant Growth Conditions

The 50 accessions for the potted experiment were planted in flower pots with a bottom diameter of 18 cm. The flower pot was filled with half soil and half sand. Each accession contained three replicates. All the accessions were cultivated in the turfgrass nursery of Nanjing Botanical Garden Mem. Sun Yat-Sen, China. Compound fertilizer was applied once a month [31]. The dosage used was 0.5 g/pot for the pot experiments. The lowest temperature in winter was −10 °C. The detailed climate information is listed in Supplementary Table S2.

2.3. Investigation of Leaf Colour during the Fall Dormancy and Coverage during the Spring Green-Up

From the end of October 2022 to the middle of December 2022, photos of potted accessions were taken during the fall dormancy. The interval at which the images were taken was 7 days. The leaf colour was scored according to the GBT30395-2013 standard as previous reported [32,33,34,35].
From the end of April 2023 to the beginning of June 2023, photos of potted accessions were taken during the green-up. The rate of green-up was obtained through visual inspection [32,33,34,36].

2.4. LT50

The experiment was conducted in September 2023. According to previous methods [37], the lethal temperature killing 50% of the plants (LT50) was determined by the electrolyte leakage method, and each treatment included 4 replicates. Briefly, the leaves of healthy plants were removed and rinsed 3 times with deionized water, after which the water that clung to the leaf surface was removed with filter paper. The leaves were cut to a length of approximately 0.5 cm and divided into 5 parts (2 g each). The samples were treated in a cryogenic circulator (Polyscience Company, Warrington, PA, USA), followed by an overnight pre-culture at 4 °C. The low-temperature gradients were set to 4, −1, −6, −11, and −16 °C. After thawing at 4 °C, the electrolyte was extracted by adding 20 mL of deionized water. The conductivity was measured with a conductivity meter (Shanghai Leici Instrument, Shanghai, China) before and after the samples were boiled in a water bath for 15 min.
electrolyte   leakage = conductivity   before   boiling   water   bath conductivity   after   boiling   water   bath ∗ 100 %
The LT50 was obtained by fitting the logistic growth equation:
Y = YM ∗ Y 0 YM − Y 0 ∗ exp − k ∗ x + Y 0
where Y is the electrolyte leakage, x is the temperature, and YM and Y0 are the maximal and initial electrolyte leakage. K is the rate constant. The LT50 is the x value where Y equals 50%.

2.5. Stolon Regrowth Experiments

The experiment was conducted in September 2023. Using the methods in [38], stolon regrowth was evaluated via the number of stolons regenerated after low-temperature treatment. The stolons with 5 nodes were treated with 5 temperature gradients (8, 3, −2, −7, and −12 °C). Each treatment included 3 replicates (10 stolons per replicate). After thawing at 4 °C for 24 h, the stolons were planted in plugs filled with half soil and half sand. After 7 days of cultivation in the laboratory, the number of regrowing stolons was determined.

2.6. Membership Function Analysis

The comprehensive cold tolerance evaluation was carried out using the membership function method [39,40,41]. Briefly, the subordination function value of the average greenness, average coverage, and total relative regrowth rates were calculated by the following equation:
Uij = Xij − Ximin Ximax − Ximin
whereas the subordination function value of the LT50 was calculated by the following equation:
Uij = 1 − Xij − Ximin Ximax − Ximin
i: a certain material, j: the index, U: the membership grade, Xij: the measured value of the index in a certain material, Ximin: the minimum value of the index in material i, and Ximax: the maximum value of the index in material i.

2.7. Data Statistics and Graphing

The cluster analysis was performed by using squared Euclidean distance coefficient and linkage between groups cluster method in SPSS 19.0 software. Correlation analysis was conducted using Graphpad Prism 9.5 software. For the tables, the data presented are the means ± standard error of at least three replicates. The differences among accessions in a same column was assessed using SPSS 19.0 software and a significant difference is indicated by different letters.

3. Results

3.1. Investigation of Leaf Greenness during the Fall Dormancy and the Coverage during the Spring Green-Up Using the Pot Experiment

Since only 55 accessions survived a winter among the 80 accessions (Supplementary Table S1), detailed cold tolerance evaluations were conducted on the surviving 55 accessions. The investigation of leaf greenness began at the end of October and lasted until late December. As autumn and winter continued, the leaf greenness of Stenotaphrum gradually decreased and all the accessions progressed to a withered yellow state at the end of the monitoring period (Table 1). To objectively reflect the trend of changes in greenness, we averaged the data from 8 time points and obtained the average greenness. This indicator was subsequently used to rank the greenness of the 55 accessions in autumn and winter. The greater the average greenness was, the longer the green period was during the fall dormancy. The average greenness of these accessions varied greatly, ranging from 4.625 to 1.375. The three accessions with the highest average greenness were ST003, S12, and 674925-1. The three accessions with the lowest average greenness were S01, S27, and S28.
The investigation of coverage began at the end of April and lasted until early June. As the green-up period progressed, the grass gradually turned green, and by the end of monitoring, most accessions had approached a complete green-up state (Table 2). To objectively reflect the trend of this green-up change, we averaged the greening coverage at four-time points and obtained the average coverage. By using this indicator, the average coverage of the 55 accessions during the green-up was ranked. A higher average coverage indicates the faster green-up ability of an accession. The average coverage varied greatly among the accessions, ranging from 85% to 9%. The three accessions with the highest average coverage were 291594, S62, and S13. The three accessions with the lowest average coverage were S02, S10, and S28.

3.2. Membership Function Analysis and Cluster Analysis Based on Pot Experiment Results

The data for the leaf colour during the fall dormancy and the turfgrass coverage during the spring green-up was analysed using membership function analysis. The score obtained was used to rank the cold tolerance. The cold tolerance varied greatly among the accessions, ranging from 0.87 to 0. The three accessions with the highest cold tolerance were ST003, S13, and S12. The three accessions with the lowest cold tolerance were S27, S02, and S28 (Table 3). The picture of these six accessions at fall dormancy and spring green-up was presented in Supplementary Figure S1. Cluster analysis revealed that these accessions were divided into two categories: cold tolerant and cold sensitive (Figure 1). The cold tolerance category can be further subdivided into two subcategories: super cold-tolerance and middle cold-tolerance. The cold sensitive category can be subdivided into two subcategories: super cold-sensitive and middle cold-sensitive (Figure 1). The accessions ranking 1–13 are mainly concentrated in the super cold-tolerant subcategory. The accessions ranking 14–46 are mainly concentrated in middle cold-tolerant subcategory. Those that ranked 47–51 are gathered in the middle cold-sensitive subcategory, and those that ranked 52–55 are gathered in the super cold-sensitive subcategory (Figure 1).
The correlation analysis revealed that a positive correlation existed between autumn/winter leaf greenness and the turfgrass coverage during the spring green-up (Figure 2). Accessions with delayed fall dormancy will have an early spring green-up rate. However, the poor R2 (0.1682) indicates a weak correlation, suggesting that it is inappropriate to simplify the cold resistance evaluation by investigating the growth performance of a single period. This result was further confirmed by the discrepancy between the ranking of autumn leaf colour or spring coverage rate and the ranking of comprehensive evaluation (Table 3).

3.3. Laboratory-Based Leaf LT50 and Stolon Regrowth Rate Analysis

To investigate whether the pot evaluation can be replaced by the laboratory-based cold resistance evaluation methods, we conducted leaf LT50 and stolon regrowth rate analysis. The cold tolerance of the leaves was measured through an electrolyte leakage test (Table 4). Logistic equation fitting was performed on the relative conductivity of each accession, and the fitting degree (R2) of each equation was greater than 0.86, indicating that the equation fit was good and that the obtained LT50 was highly reliable. A more negative LT50 value indicates a greater cold tolerance ability for leaves. A significant difference in leaf LT50 was detected among the accessions, ranging from −9.32 to 3.45. The three accessions with the most favourable LT50 values were S39, S005, and 410364. The three accessions with the lowest LT50 values were S11, S006, and S27.
Since the spring green-up of Stenotaphrum depends on the budding of the stolons, the regrowth ability of the stolons was evaluated. For all the accessions, as the temperature during the low-temperature pre-treatment decreased, the ability of the stolons to regrow significantly decreased. At −7 °C, most accessions lost their ability to regrow, while at −12 °C, all accessions lost their ability to regrow (Table 5). Given the significant differences in the ability of the accessions to regrow at relatively normal temperatures (8 °C), the regrowth ability of stolons at 8 °C was used as a control and the regrowth ability of stolons under other temperature treatments was standardized. The total relative regrowth rate of stolons at low temperatures was subsequently obtained by averaging the total relative regrowth rate of stolons at −3 °C, −2 °C, and −7 °C. A higher total relative regrowth rate indicates a greater ability for stolons to regrow in the next year. The total relative regrowth rate varied greatly among the accessions, ranging from 52% to 13%. The top three accessions in terms of total relative regrowth rate were S30, S39, and S25. The three accessions with the lowest total relative regrowth rates were S27, S10, and 300129.

3.4. Membership Function Analysis and Cluster Analysis Based on Laboratory Results

The score and rank based on the laboratory results were obtained by membership function analysis (Table 6). A significant difference between the laboratory-based rank and the pot-evaluated rank was detected, and the coincidence degree between them was poor (Table 3 and Table 6). Cluster analysis revealed that these accessions could be divided into two categories and three subcategories based on the laboratory results (Figure 3). Specifically, the accessions ranking 1–9 are clustered in one subcategory (cold-tolerant). The accessions ranking 10–50 are clustered in one subcategory (middle cold-sensitive), while those rankings 51–55 are clustered in one subcategory (super cold-sensitive) (Figure 3). A very poor consistency with the clustering results between the pot evaluation and the laboratory-based evaluation was found (Figure 1 and Figure 3).

3.5. Correlation Analysis between the Laboratory-Based Data and the Pot Analysis Data

A correlation analysis was conducted between LT50 and other data. It was found that LT50 was not correlated with the average greenness during the autumn/winter nor average coverage during the spring green-up but was correlated with the total relative regrowth rate (Figure 4).
A correlation analysis was conducted between the total relative regrowth rate and other data. It was found that the total relative regrowth rate was not correlated with average greenness but was positively correlated with average coverage during the spring green-up (Figure 5).

4. Discussion

4.1. Establishment of a Method for Evaluating the Cold Tolerance of Stenotaphrum by Integrating Its Performance at Both the Fall Dormancy and the Spring Green-Up

It is assumed that the cold resistance of the leaves of perennial turfgrass is crucial when it first encounters autumn/winter cold, while the regrowth ability of stolons is crucial for rapid spring green-up. Briefly, when plants encounter chilling injury, their leaves strive to maintain photosynthesis by prolonging the green period and synthesizing energy to resist chilling injury. Secondly, the leaves transport photosynthate to the stolon to store energy for spring green-up. Leaves with a strong cold resistance are more conducive to the implementation of the above process. The bud from the stolon was the initial site for spring green-up. Therefore, the cold tolerance of perennial turfgrass relies on both the leaves and stolons. This mechanism is completely different from the mechanism of cold resistance in annual plants, which do not experience fall dormancy and spring green-up [42,43,44]. Moreover, the use of an evaluation system for the cold resistance of annual plants is inappropriate for evaluating the cold resistance of perennials [45,46,47,48]. A successful cold-tolerant perennial grass plant needs to be characterized by both delayed fall dormancy and early spring green-up. In this study, through the dynamic investigation of changes in leaf colour in autumn/winter and green coverage in the following year and the membership function analysis and cluster analysis, the growth performance of 55 Stenotaphrum accessions in these two stages was evaluated (Table 1, Table 2 and Table 3; Figure 1). This improved evaluation method compensates for the limitation of the previous cold tolerance evaluation method, which mainly focused on the spring green-up stage and paid less attention to fall dormancy [10,11]. The cold-tolerant accessions selected by this improved method have more ornamental value and are easier for the public to accept. The results showing that the autumn/winter leaf colour and the spring green-up coverage has a weak correlation and that the rank fit between a single period and these two periods is poor indicates that the growth performance of a single period cannot replace the overall evaluation (Figure 2; Table 3). The use of technical methods can only regulate the growth performance of one period (e.g., fall dormancy) and does not affect the growth performance of another period (e.g., spring green-up), supporting the above results [49,50].

4.2. This Improved Evaluation Method Cannot Be Replaced by Laboratory Evaluation

The laboratory-based cold tolerance results and the pot cold tolerance results are inconsistent (Table 3 and Table 6; Figure 1 and Figure 3). There was no correlation between LT50 and the autumn leaf colour or the spring green-up coverage. The total relative regrowth was not correlated with the autumn/winter leaf colour and only correlated with the next year’s green coverage (Figure 4 and Figure 5). This explains why LT50 and stolon regrowth data cannot fully reflect the cold resistance of Stenotaphrum accessions. The inconsistency of the LT50 or the stolon regrowth data to the cold tolerance found in other perennial grass might be also partially attributed to this reason [16,17].
The stolon regrowth rate is positively correlated with the spring green-up coverage (Figure 5), which is in agreement with reports on other turfgrasses [5,51]. These data can to some extent reflect the situation of spring green-up of turfgrass. However, caution should be taken when using this method for cold tolerance evaluation in the future due to the weak correlation.

4.3. Screening of Several Excellent Cold-Tolerant Accessions That Can Be Directly Used in Temperate Regions of China

Through the comprehensive evaluation method, we selected excellent-cold-resistance accessions, which were represented by ST003, S13, and S12 (Table 3). These excellent accessions were obtained from Sydney, Australia, Wenchang, Hainan (China), and Tengchong, Yunnan (China) (Supplementary Table S1). Although several studies have evaluated the cold resistance of Stenotaphrum plants, most have focused on accessions from Europe and North America [19,20,21,22]. This study evaluated the cold resistance of Stenotaphrum plants mainly using Chinese accessions. Due to cold tolerance being an important factor limiting plant geographical distribution [52] and cold tolerance being evaluated in temperate regions in China, the selected excellent-cold-resistance accessions can be directly applied locally. In the future, we plan to further evaluate the shade tolerance of these cold-tolerant accessions and screen for excellent shade-tolerant grass accessions that can be applied in temperate regions.

5. Conclusions

A turfgrass with good cold resistance should have both the advantage of delayed fall dormancy and early spring green-up. Based on the situation that the previous cold tolerance evaluation of turfgrass mainly focused on the spring green-up and paid less attention to its performance in the fall dormancy, this study integrates the performance of these two stages by dynamically investigating the autumn/winter leaf colour and next year’s coverage and uses membership functions and cluster analysis to comprehensively evaluate the cold resistance of 55 Stenotaphrum accessions. This method cannot be simplified by the performance of one period, nor can it be replaced by indicator measurements conducted in the laboratory. The establishment of this method compensates for the shortcomings of previous methods for evaluating the cold tolerance of turfgrass. With the help of this improved method, we have screened several excellent-cold-tolerance accessions (ST003, S13, and S12) for the temperate regions of East China.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/horticulturae10070761/s1, Table S1: Aaccession information; Table S2: Extreme temperature and rainfall in Nanjing during the experimental process; Figure S1: The performance of six accessions with extreme cold tolerance and cold sensitivity.

Author Contributions

J.-Q.Z. and Z.-Y.W. designed the work. J.Q. and D.-L.H. carried out the experiments. D.-L.H., J.-Q.Z. and Z.-Y.W. wrote the paper. J.-Y.Z., J.-B.C., D.-J.S. and J.-X.L. revised the paper. All authors contributed to the article. All authors have read and agreed to the published version of the manuscript.

Funding

The authors are grateful for the financial support provided by the Forestry Science and Technology Innovation and Promotion Project of Jiangsu Province (LYKJ[2023]17), the Jiangsu Provincial Double-Innovation Doctor Program (Grant No. JSSCBS20221643), the Jiangsu Institute of Botany Talent Fund (Grant No. JIBTF202210), and the Program for the Young Innovative Talents of Jiangsu Vocational College of Agriculture and Forest (Grant No. 2021kj26).

Data Availability Statement

The original contributions presented in the study are included in the article/Supplementary Materials, further inquiries can be directed to the corresponding authors.

Conflicts of Interest

The authors declare no competing interests.

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Horticulturae 10 00761 g001
Figure 1. Cluster analysis based on pot experiment results.
Figure 1. Cluster analysis based on pot experiment results.
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Figure 2. Correlation between the average greenness during the fall dormancy and average coverage during the spring green-up. The P and R2 are the fitted parameters. The symbol * indicates a correlation.
Figure 2. Correlation between the average greenness during the fall dormancy and average coverage during the spring green-up. The P and R2 are the fitted parameters. The symbol * indicates a correlation.
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Figure 3. Cluster analysis based on laboratory results.
Figure 3. Cluster analysis based on laboratory results.
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Figure 4. Correlation between LT50 and other parameters. (A) Correlation between LT50 and average greenness. (B) Correlation between LT50 and average coverage. (C) Correlation between LT50 and total relative regrowth rate. The P and R2 are the fitted parameters. The symbol * indicates a correlation.
Figure 4. Correlation between LT50 and other parameters. (A) Correlation between LT50 and average greenness. (B) Correlation between LT50 and average coverage. (C) Correlation between LT50 and total relative regrowth rate. The P and R2 are the fitted parameters. The symbol * indicates a correlation.
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Horticulturae 10 00761 g005
Figure 5. Correlation between total relative regrowth rate and other parameters. (A) Correlation between total relative regrowth rate and average greenness. (B) Correlation between total relative regrowth rate and average coverage. The P and R2 are the fitted parameters. The symbol * indicates a correlation.
Figure 5. Correlation between total relative regrowth rate and other parameters. (A) Correlation between total relative regrowth rate and average greenness. (B) Correlation between total relative regrowth rate and average coverage. The P and R2 are the fitted parameters. The symbol * indicates a correlation.
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Table 1. Leaf greenness during the fall dormancy.
Table 1. Leaf greenness during the fall dormancy.
NameLeaf GreennessAv. Greenness
29 October5 November12 November19 November26 November5 December10 December17 December
ST0037.000 ± 0.577b7.000 ± 0.577a6.000 ± 0.289a5.000 ± 0.000a4.000 ± 0.289a3.000 ± 0.000a3.000 ± 0.000a2.000 ± 0.577a4.625 ± 0.289a
S127.000 ± 0.000b7.000 ± 0.000a6.000 ± 0.289a5.000 ± 0.289a4.000 ± 0.000a3.000 ± 0.577a2.000 ± 0.289b1.000 ± 0.000b4.375 ± 0.180ab
674925-17.000 ± 0.000b7.000 ± 0.000a6.000 ± 0.289a4.000 ± 0.577b3.000 ± 0.000b3.000 ± 0.000a2.000 ± 0.000b1.000 ± 0.000b4.125 ± 0.108bc
674925-37.000 ± 0.000b7.000 ± 0.000a6.000 ± 0.289a4.000 ± 0.000b3.000 ± 0.000b3.000 ± 0.000a2.000 ± 0.289b1.000 ± 0.000b4.125 ± 0.072bc
4103618.000 ± 0.577a7.000 ± 0.577a6.000 ± 0.289a4.000 ± 0.000b3.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b4.000 ± 0.180cd
S0047.000 ± 0.000b6.000 ± 0.000b5.000 ± 0.000b4.000 ± 0.289b3.000 ± 0.000b3.000 ± 0.000a2.000 ± 0.289b1.000 ± 0.000b3.875 ± 0.072cde
S047.000 ± 0.577b6.000 ± 0.000b5.000 ± 0.000b4.000 ± 0.000b3.000 ± 0.000b3.000 ± 0.000a2.000 ± 0.000b1.000 ± 0.000b3.875 ± 0.072cde
S086.000 ± 0.000b6.000 ± 0.000b6.000 ± 0.000a4.000 ± 0.577b3.000 ± 0.289b3.000 ± 0.289a2.000 ± 0.289b1.000 ± 0.000b3.875 ± 0.180cde
S256.000 ± 0.000b6.000 ± 0.000b6.000 ± 0.000a4.000 ± 0.577b3.000 ± 0.289b3.000 ± 0.289a2.000 ± 0.289b1.000 ± 0.000b3.875 ± 0.180cde
S397.000 ± 0.000b6.000 ± 0.000b5.000 ± 0.000b4.000 ± 0.000b3.000 ± 0.289b3.000 ± 0.289a2.000 ± 0.000b1.000 ± 0.000b3.875 ± 0.072cde
S487.000 ± 0.000b6.000 ± 0.000b6.000 ± 0.000a4.000 ± 0.577b3.000 ± 0.289b2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.875 ± 0.108cde
S137.000 ± 0.000b6.000 ± 0.000b5.000 ± 0.000b4.000 ± 0.000b3.000 ± 0.000b2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.75 ± 0.000de
S267.000 ± 0.000b6.000 ± 0.000b5.000 ± 0.000b4.000 ± 0.000b3.000 ± 0.000b2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.75 ± 0.000de
S316.000 ± 0.000b6.000 ± 0.000b5.000 ± 0.000b4.000 ± 0.000b3.000 ± 0.000b3.000 ± 0.000a2.000 ± 0.000b1.000 ± 0.000b3.75 ± 0.000de
S587.000 ± 0.577b6.000 ± 0.289b5.000 ± 0.000b4.000 ± 0.000b2.000 ± 0.000c2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.625 ± 0.108ef
647924-27.000 ± 0.289b6.000 ± 0.000b5.000 ± 0.289b3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b3.375 ± 0.072fg
S146.000 ± 0.000b5.000 ± 0.000c4.000 ± 0.000c4.000 ± 0.000b3.000 ± 0.289b2.000 ± 0.289b2.000 ± 0.289b1.000 ± 0.000b3.375 ± 0.108fg
S526.000 ± 0.577b5.000 ± 0.000c5.000 ± 0.000b3.000 ± 0.000c3.000 ± 0.000b2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.375 ± 0.072fg
S0076.000 ± 0.000b5.000 ± 0.000c4.000 ± 0.000c3.000 ± 0.000c3.000 ± 0.000b2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.25 ± 0.000gh
S106.000 ± 0.289b5.000 ± 0.000c4.000 ± 0.577c3.000 ± 0.577c3.000 ± 0.000b2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.25 ± 0.180gh
2915947.000 ± 0.000b5.000 ± 0.577c4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b3.125 ± 0.072ghi
3001297.000 ± 0.000b5.000 ± 0.000c4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b3.125 ± 0.000ghi
3001307.000 ± 0.000b5.000 ± 0.577c4.000 ± 0.289c3.000 ± 0.289c2.000 ± 0.289c2.000 ± 0.289b1.000 ± 0.000c1.000 ± 0.000b3.125 ± 0.253ghi
S226.000 ± 0.000b6.000 ± 0.000b4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b3.125 ± 0.000ghi
S375.000 ± 0.577c4.000 ± 0.000d4.000 ± 0.000c3.000 ± 0.000c3.000 ± 0.000b2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.125 ± 0.072ghi
4103646.000 ± 0.000b5.000 ± 0.000c4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b3.000 ± 0.000hij
674924-26.000 ± 0.289b5.000 ± 0.289c4.000 ± 0.000c3.000 ± 0.289c2.000 ± 0.289c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b3.000 ± 0.182hij
S116.000 ± 0.000b4.000 ± 0.289d4.000 ± 0.289c3.000 ± 0.289c2.000 ± 0.000c2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.000 ± 0.108hij
S236.000 ± 0.000b5.000 ± 0.000c4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b3.000 ± 0.000hij
S536.000 ± 0.000b4.000 ± 0.000d4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b3.000 ± 0.000hij
5090386.000 ± 0.000b5.000 ± 0.000c3.000 ± 0.000d3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.875 ± 0.000ijk
S0065.000 ± 0.577c4.000 ± 0.000d4.000 ± 0.000c3.000 ± 0.289c2.000 ± 0.289c2.000 ± 0.289b2.000 ± 0.289b1.000 ± 0.000b2.875 ± 0.218ijk
S465.000 ± 0.000c4.000 ± 0.000d4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b2.875 ± 0.000ijk
S546.000 ± 0.577b4.000 ± 0.000d4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.875 ± 0.072ijk
4103635.000 ± 0.000c5.000 ± 0.000c3.000 ± 0.000d3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.750 ± 0.000jkl
S215.000 ± 0.000c4.000 ± 0.000d4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.750 ± 0.000jkl
S295.000 ± 0.000c5.000 ± 0.000c3.000 ± 0.289d3.000 ± 0.289c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.750 ± 0.072jkl
S385.000 ± 0.000c5.000 ± 0.000c3.000 ± 0.000d2.000 ± 0.000d2.000 ± 0.000c2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b2.750 ± 0.000jkl
S444.000 ± 0.000d4.000 ± 0.000d3.000 ± 0.000d3.000 ± 0.000c2.000 ± 0.000b2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b2.750 ± 0.000jkl
S625.000 ± 0.577c4.000 ± 0.289d4.000 ± 0.289c3.000 ± 0.289c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.750 ± 0.180jkl
S305.000 ± 0.000c4.000 ± 0.000d3.000 ± 0.000d3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.625 ± 0.000klm
S476.000 ± 0.000b5.000 ± 0.577c4.000 ± 0.000c2.000 ± 0.000d1.000 ± 0.000d1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b2.625 ± 0.072klm
S495.000 ± 0.577c4.000 ± 0.000d4.000 ± 0.000c3.000 ± 0.000c2.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b2.625 ± 0.072klm
S554.000 ± 0.000d4.000 ± 0.000d3.000 ± 0.000d3.000 ± 0.000c2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.5 ± 0.000lmn
S0056.000 ± 0.000b4.000 ± 0.000d3.000 ± 0.000d2.000 ± 0.000d1.000 ± 0.000d1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b2.375 ± 0.000mn
S504.000 ± 0.000d4.000 ± 0.000d3.000 ± 0.577d3.000 ± 0.000c2.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b2.375 ± 0.072mn
G0014.000 ± 0.000d4.000 ± 0.000d3.000 ± 0.000d2.000 ± 0.000d2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.375 ± 0.000mn
S454.000 ± 0.000d3.000 ± 0.577e2.000 ± 0.000e2.000 ± 0.000d2.000 ± 0.000c2.000 ± 0.000b2.000 ± 0.000b1.000 ± 0.000b2.250 ± 0.072n
S515.000 ± 0.577c4.000 ± 0.000d3.000 ± 0.000d2.000 ± 0.000d1.000 ± 0.000d1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b2.250 ± 0.072n
S574.000 ± 0.577d3.000 ± 0.289e3.000 ± 0.289d2.000 ± 0.000d2.000 ± 0.000c2.000 ± 0.000b1.000 ± 0.000c1.000 ± 0.000b2.250 ± 0.144n
S564.000 ± 0.289d3.000 ± 0.000e3.000 ± 0.000d2.000 ± 0.000d1.000 ± 0.000d1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b2.000 ± 0.036n
S023.000 ± 0.577e2.000 ± 0.000f2.000 ± 0.000e1.000 ± 0.000e1.000 ± 0.000d1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b1.500 ± 0.072o
S012.000 ± 0.000f2.000 ± 0.000f2.000 ± 0.000e1.000 ± 0.000e1.000 ± 0.000d1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b1.375 ± 0.000o
S273.000 ± 0.000e2.000 ± 0.000f1.000 ± 0.000f1.000 ± 0.000e1.000 ± 0.000d1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b1.375 ± 0.000o
S283.000 ± 0.000e2.000 ± 0.000f1.000 ± 0.000f1.000 ± 0.000e1.000 ± 0.000d1.000 ± 0.000c1.000 ± 0.000c1.000 ± 0.000b1.375 ± 0.000o
Note: the word “Average” was abbreviated as Av. The significant differences among accessions in a same column is indicated by different letters.
Table 2. Coverage survey at the spring green-up.
Table 2. Coverage survey at the spring green-up.
NameCover (%)Av. Cover (%)
28 April7 May27 May6 June
29159460.000 ± 0.000a80.000 ± 0.012a98.000 ± 0.015abc100.000 ± 0.000a84.500 ± 0.007a
S6260.000 ± 0.010a70.000 ± 0.000b100.000 ± 0.000a100.000 ± 0.000a82.500 ± 0.003ab
S1360.000 ± 0.006a65.000 ± 0.020c98.000 ± 0.010abc100.000 ± 0.000a80.750 ± 0.009bc
S5860.000 ± 0.000a58.000 ± 0.020e100.000 ± 0.000a100.000 ± 0.000a79.500 ± 0.002cd
S5755.000 ± 0.020b63.000 ± 0.010cd93.000 ± 0.017def100.000 ± 0.000a77.750 ± 0.011de
S0850.000 ± 0.000c55.000 ± 0.029e99.000 ± 0.000ab100.000 ± 0.000a76.000 ± 0.007ef
S00650.000 ± 0.029c53.000 ± 0.015ef92.000 ± 0.017defg100.000 ± 0.000a73.750 ± 0.015fg
S3935.000 ± 0.000f60.000 ± 0.015d100.000 ± 0.000a100.000 ± 0.000a73.750 ± 0.004fg
S4740.000 ± 0.020e55.000 ± 0.012e100.000 ± 0.000a100.000 ± 0.000a73.750 ± 0.008fg
S00745.000 ± 0.000d54.000 ± 0.01ef90.000 ± 0.000fg100.000 ± 0.000a72.250 ± 0.003gh
S2535.000 ± 0.000f55.000 ± 0.000e93.000 ± 0.015def100.000 ± 0.000a70.750 ± 0.004hi
S3035.000 ± 0.029f55.000 ± 0.029e90.000 ± 0.000fg100.000 ± 0.000a70.000 ± 0.014hi
S00535.000 ± 0.000f50.000 ± 0.000fg94.000 ± 0.029cdef100.000 ± 0.000a69.750 ± 0.007i
647924-230.000 ± 0.000g55.000 ± 0.000e90.000 ± 0.000fg100.000 ± 0.000a68.750 ± 0.000i
S2235.000 ± 0.000f50.000 ± 0.000fg90.000 ± 0.000fg100.000 ± 0.000a68.750 ± 0.000i
S4835.000 ± 0.000f50.000 ± 0.000fg90.000 ± 0.000fg100.000 ± 0.000a68.750 ± 0.000i
674925-125.000 ± 0.029h60.000 ± 0.000d88.000 ± 0.029gh100.000 ± 0.000a68.250 ± 0.014ij
S5125.000 ± 0.000h52.000 ± 0.015ef96.000 ± 0.015abcd100.000 ± 0.000a68.250 ± 0.008ij
S2932.000 ± 0.015fg50.000 ± 0.000fg90.000 ± 0.000fg100.000 ± 0.000a68.000 ± 0.004ijk
S5230.000 ± 0.000g43.000 ± 0.015hi98.000 ± 0.012abc100.000 ± 0.000a67.750 ± 0.007ijk
S5430.000 ± 0.000g50.000 ± 0.000fg90.000 ± 0.000fg100.000 ± 0.000a67.500 ± 0.000ijk
S3730.000 ± 0.000g55.000 ± 0.029e88.000 ± 0.015efg96.000 ± 0.020b67.250 ± 0.022ijk
S2630.000 ± 0.000g45.000 ± 0.029h90.000 ± 0.000fg100.000 ± 0.000a66.250 ± 0.007jkl
S2320.000 ± 0.000j50.000 ± 0.000fg94.000 ± 0.015cdef100.000 ± 0.000a66.000 ± 0.004jkl
S5640.000 ± 0.000e47.000 ± 0.018gh85.000 ± 0.000h90.000 ± 0.000c65.500 ± 0.004kl
S3120.000 ± 0.000j45.000 ± 0.000h96.000 ± 0.015abcd100.000 ± 0.000a65.250 ± 0.004kl
S5025.000 ± 0.000h40.000 ± 0.000ij96.000 ± 0.020abcd100.000 ± 0.000a65.250 ± 0.005lm
674924-215.000 ± 0.000k45.000 ± 0.029h100.000 ± 0.000a100.000 ± 0.000a65.000 ± 0.007lm
S1420.000 ± 0.000j60.000 ± 0.000d80.000 ± 0.000i100.000 ± 0.000a65.000 ± 0.000lmn
S3820.000 ± 0.000j40.000 ± 0.000ij100.000 ± 0.000a100.000 ± 0.000a65.000 ± 0.000lmn
ST00325.000 ± 0.029h35.000 ± 0.029k100.000 ± 0.000a100.000 ± 0.000a65.000 ± 0.014lmn
S1240.000 ± 0.000e38.000 ± 0.015jk80.000 ± 0.000i100.000 ± 0.000a64.500 ± 0.004lmn
S0410.000 ± 0.000lm45.000 ± 0.029h96.000 ± 0.010abcd100.000 ± 0.000a62.750 ± 0.009mno
S5520.000 ± 0.000j37.000 ± 0.015jk94.000 ± 0.006cdef100.000 ± 0.000a62.750 ± 0.005no
S4915.000 ± 0.000k40.000 ± 0.000ij90.000 ± 0.000fg100.000 ± 0.000a61.250 ± 0.000op
G00115.000 ± 0.000k35.000 ± 0.000k95.000 ± 0.000bcde100.000 ± 0.000a61.250 ± 0.000op
S532.000 ± 0.010op38.000 ± 0.012jk99.000 ± 0.006ab100.000 ± 0.000a59.750 ± 0.007p
S4610.000 ± 0lm20.000 ± 0.000n96.000 ± 0.010abcd100.000 ± 0.000a56.500 ± 0.003q
4103638.000 ± 0.015mn25.000 ± 0.000m80.000 ± 0.000i100.000 ± 0.000a53.250 ± 0.004r
3001300.000 ± 0.000p35.000 ± 0.000k75.000 ± 0.000j100.000 ± 0.000a52.500 ± 0.000r
50903812 ± 0.015kl18.000 ± 0.015no80.000 ± 0.000i100.000 ± 0.000a52.500 ± 0.008r
4103641.000 ± 0.000p30.000 ± 0.000l70.000 ± 0.000k100.000 ± 0.000a50.250 ± 0.000s
674925-35.000 ± 0.000no20.000 ± 0.000n70.000 ± 0.000k100.000 ± 0.000a48.750 ± 0.000s
S2115.000 ± 0.029k30.000 ± 0.029l60.000 ± 0.000l85.000 ± 0.000d47.500 ± 0.014s
41036110.000 ± 0.000lm30.000 ± 0.000l55.000 ± 0.029m80.000 ± 0.000e43.750 ± 0.007t
S0042.000 ± 0.010op10.000 ± 0.000p70.000 ± 0.000k90.000 ± 0.000c43.000 ± 0.003t
S4510.000 ± 0.000lm25.000 ± 0.029m55.000 ± 0.029m65.000 ± 0.029f38.750 ± 0.022u
S115.000 ± 0.000no5.000 ± 0.000q45.000 ± 0.000n60.000 ± 0.000g28.750 ± 0.000v
S445.000 ± 0.000no7.000 ± 0.006pq30.000 ± 0.000o40.000 ± 0.000h20.500 ± 0.001w
3001297.000 ± 0.017mn15.000 ± 0.000o20.000 ± 0.000p35.000 ± 0.000i19.250 ± 0.004w
S012.000 ± 0.000op8.000 ± 0.015pq25.000 ± 0.000o40.000 ± 0.000h18.750 ± 0.004w
S272.000 ± 0.010op8.000 ± 0.010pq30.000 ± 0.000o35.000 ± 0.000i18.750 ± 0.005w
S022.000 ± 0.000op6.000 ± 0.006pq15.000 ± 0.000q30.000 ± 0.000j13.250 ± 0.001x
S100.000 ± 0.000p5.000 ± 0.000q15.000 ± 0.000q25.000 ± 0.000k11.250 ± 0.000y
S281.000 ± 0.000p5.000 ± 0.000q10.000 ± 0.000r20.000 ± 0.000l9.000 ± 0.000y
Note: the word “Average” was abbreviated as Av. The significant differences among accessions in a same column is indicated by different letters.
Table 3. Membership function analysis based on pot experiment results. Note: the word “Average” was abbreviated as Av. The significant differences among accessions in a same column is indicated by different letters.
Table 3. Membership function analysis based on pot experiment results. Note: the word “Average” was abbreviated as Av. The significant differences among accessions in a same column is indicated by different letters.
AccessionAv. GreennessAv. CoverageScoreRank
ST0031.000 ± 0.000a0.741 ± 0.012m0.871 ± 0.006a1
S130.742 ± 0.066cd0.950 ± 0.004c0.846 ± 0.032ab2
S120.927 ± 0.027ab0.735 ± 0.001m0.831 ± 0.014abc3
S080.771 ± 0.013cd0.887 ± 0.002e0.829 ± 0.005abcd4
674925-10.853 ± 0.043bc0.784 ± 0.012ijk0.819 ± 0.015abcd5
S390.777 ± 0.047cd0.857 ± 0.002f0.817 ± 0.025abcd6
S580.697 ± 0.028de0.925 ± 0.006d0.811 ± 0.017bcd7
S250.771 ± 0.013cd0.817 ± 0.002gh0.794 ± 0.007bcde8
S480.775 ± 0.036cd0.791 ± 0.006ijk0.783 ± 0.021cde9
2915940.543 ± 0.026fgh1.000 ± 0.000a0.771 ± 0.013de10
S260.742 ± 0.066cd0.758 ± 0.003lm0.750 ± 0.031ef11
S040.777 ± 0.047cd0.711 ± 0.006n0.744 ± 0.021ef12
S310.742 ± 0.066cd0.745 ± 0.001m0.743 ± 0.034ef13
S0070.586 ± 0.052efg0.837 ± 0.004fg0.712 ± 0.028fg14
647924-20.621 ± 0.033ef0.791 ± 0.006ijk0.706 ± 0.021fgh15
S520.621 ± 0.033ef0.778 ± 0.001kl0.699 ± 0.015fgh16
S620.419 ± 0.018hijkl0.973 ± 0.005b0.696 ± 0.006fgh17
674925-30.855 ± 0.054bc0.526 ± 0.004rs0.691 ± 0.029fghi18
S140.619 ± 0.021ef0.741 ± 0.006m0.681 ± 0.014ghij19
S220.547 ± 0.049fgh0.791 ± 0.006ijk0.669 ± 0.028ghijk20
S370.543 ± 0.026fgh0.782 ± 0.022jk0.662 ± 0.002ghijkl21
S0060.443 ± 0.029hijk0.857 ± 0.012f0.651 ± 0.021hijklm22
4103610.810 ± 0.016cd0.460 ± 0.005t0.635 ± 0.005ijklmn23
S230.508 ± 0.045fghij0.754 ± 0.001lm0.631 ± 0.023jklmn24
S470.394 ± 0.057ijklm0.857 ± 0.002f0.626 ± 0.027jklmn25
S540.464 ± 0.019ghijk0.774 ± 0.006kl0.619 ± 0.013klmn26
S0040.777 ± 0.047cd0.450 ± 0.001t0.613 ± 0.024klmno27
674924-20.484 ± 0.015ghij0.741 ± 0.003m0.613 ± 0.008klmno28
S290.425 ± 0.015hijkl0.781 ± 0.001jk0.603 ± 0.008lmnop29
S300.390 ± 0.035jklmn0.807 ± 0.012hi0.599 ± 0.011mnop30
S530.508 ± 0.045fghij0.672 ± 0.002o0.590 ± 0.021mnopq31
S570.265 ± 0.021op0.910 ± 0.007d0.587 ± 0.014nopq32
S380.429 ± 0.038hijkl0.741 ± 0.006m0.585 ± 0.022nopqr33
S0050.312 ± 0.028lmno0.804 ± 0.002hij0.558 ± 0.012opqrs34
S460.468 ± 0.042ghijk0.629 ± 0.002p0.549 ± 0.022pqrs35
3001300.519 ± 0.033fghi0.576 ± 0.005q0.548 ± 0.014pqrs36
S490.386 ± 0.012jklmn0.692 ± 0.006no0.539 ± 0.009qrs37
S550.351 ± 0.031klmno0.711 ± 0.001n0.531 ± 0.015qrs38
4103640.508 ± 0.045fghij0.546 ± 0.004r0.527 ± 0.025rst39
S510.269 ± 0.001no0.784 ± 0.003ijk0.527 ± 0.001rst40
S500.308 ± 0.005lmno0.745 ± 0.002m0.526 ± 0.003rst41
5090380.468 ± 0.042ghijk0.576 ± 0.005q0.522 ± 0.018st42
4103630.429 ± 0.038hijkl0.586 ± 0.001q0.508 ± 0.019st43
G0010.312 ± 0.028lmno0.692 ± 0.006no0.502 ± 0.017st44
S560.193 ± 0.006p0.748 ± 0.001m0.471 ± 0.003t45
S210.429 ± 0.038hijkl0.509 ± 0.014s0.469 ± 0.012t46
S110.502 ± 0.011fghij0.261 ± 0.002v0.381 ± 0.006u47
3001290.547 ± 0.049fgh0.135 ± 0.004w0.341 ± 0.022uv48
S450.277 ± 0.047mno0.393 ± 0.025u0.335 ± 0.011uv49
S100.576 ± 0.004gf0.029 ± 0.001y0.302 ± 0.002v50
S440.429 ± 0.038hijkl0.152 ± 0.001w0.291 ± 0.019v51
S010.000 ± 0.000q0.129 ± 0.003wx0.064 ± 0.001w52
S270.000 ± 0.000q0.129 ± 0.005x0.064 ± 0.002w53
S020.035 ± 0.019q0.056 ± 0.001x0.045 ± 0.011wx54
S280.000 ± 0.000q0.000 ± 0.000z0.000 ± 0.000x55
Table 4. Leaf LT50.
Table 4. Leaf LT50.
NameFitted EquationR2LT50
S39Y = 0.0001214257/(0.726933e(0.9834X) + 0.000167)0.9962−9.322
S005Y = 0.00009260336/(0.99510695e(1.062X) + 0.00009305)0.9936−8.744
410364Y = 0.000057860928/(0.99514186e(1.128X) + 0.00005814)0.9938−8.651
674925-1Y = 0.00012980552/(0.9599648e(1.041X) + 0.0001352)0.9953−8.598
S22Y = 0.009776992/(0.87537e(0.5697X) + 0.01103)0.9388−8.130
S25Y = 0.0060481639/(0.856899e(0.6375X) + 0.007001)0.9382−8.039
S30Y = 0.000074015504/(0.98732504e(1.254X) + 0.00007496)0.9932−7.584
S14Y = 0.00101304/(1.003992e(0.9263X) + 0.001008)0.9303−7.442
S13Y = 0.001925836/(1.010097e(0.8403X) + 0.001903)0.9207−7.431
S55Y = 0.00072324/(1.0072825e(0.9924X) + 0.0007175)0.9509−7.286
509038Y = 0.0319708/(0.9969e(0.518X) + 0.0311)0.9763−6.588
S47Y = 0.244601/(0.9515e(0.2011X) + 0.2105)0.951−6.105
s46Y = 0.034527/(0.98615e(0.5549X)+0.03385)0.9939−6.005
410363Y = 0.0050289084/(0.886966e(1.136X) + 0.005634)0.9972−4.666
S57Y = 0.004862/(0.995138e(1.165X) + 0.004862)0.9906−4.567
300130Y = 0.002255/(0.997745e(1.455X) + 0.002255)0.996−4.187
G001Y = 0.05019384/(0.93299e(0.7484X) + 0.05101)0.9973−3.926
S51Y = 0.11036856/(0.841e(0.5361X) + 0.1154)0.9734−3.875
S58Y = 0.2392359/(0.8063e(0.3166X) + 0.2307)0.9029−3.726
ST003Y = 0.14605676/(0.8111e(−0.4706X) + 0.1517)0.9755−3.726
674925-3Y = 0.251808/(0.788e(0.306X) + 0.244)0.9965−3.628
647924-2Y = 0.2639386/(0.7887e(−0.2983X) + 0.2533)0.9962−3.537
S04Y = 0.01177386/(0.9775e(1.343X) + 0.0119)0.9986−3.298
S02Y = 0.02462/(0.97538e(1.119X) + 0.02462)0.999−3.287
S26Y = 0.29094953/(0.6728e(0.2717X) + 0.2993)0.945−3.192
S29Y = 0.081644706/(0.87528e(0.778X) + 0.08502)0.9446−3.103
S31Y = 0.00738243/(0.982543e(1.627X) + 0.007457)0.9968−3.012
410361Y = 0.019615484/(0.97498e(1.302X) + 0.01972)0.9963−3.004
S44Y = 0.0661362/(0.8303e(0.8921X) + 0.0732)0.9909−2.962
S48Y = 0.038806316/(0.94997e(1.092X) + 0.03923)0.9937−2.938
S49Y = 0.016183542/(0.96979e(−1.436X)+0.01641)0.975−2.860
S01Y = 0.06156948/(0.92834e(0.9526X) + 0.06216)0.9834−2.858
674924-2Y = 0.12187968/(0.8518e(0.6895X) + 0.1248)0.9736−2.855
S23Y = 0.049398912/(0.93632e(1.055X) + 0.05008)0.9893−2.801
S52Y = 0.4486097/(0.8117e(0.1628X) + 0.3773)0.9669−2.736
S08Y = 0.16656668/(0.8332e(0.6524X) + 0.1666)0.9569−2.467
S004Y = 0.1205039/(0.8749e(0.8163X) + 0.121)0.9124−2.433
S53Y = 0.054600213/(0.94213e(1.266X) + 0.05477)0.9529−2.252
291594Y = 0.37764/(0.689e(0.2548X) + 0.36)0.977−2.181
S007Y = 0.033322732/(0.96213e(1.551X) + 0.03347)0.9852−2.171
S38Y = 0.23126787/(0.7486e(0.5685X) + 0.2351)0.9767−2.095
S12Y = 0.18992891/(0.809e(0.736X) + 0.1901)0.9566−1.971
S54Y = 0.27675508/(0.5583e(0.4981X) + 0.3164)0.9954−1.719
S45Y = 0.3547992/(0.6842e(0.3752X) + 0.3448)0.9328−1.676
300129Y = 0.335682/(0.6909e(0.4776X) + 0.3291)0.9623−1.471
S62Y = 0.393151/(0.6483e(0.3226X) + 0.3817)0.9171−1.461
S37Y = 0.4515098/(0.6016e(0.2602X) + 0.4354)0.9082−0.968
S50Y = 0.4506476/(0.5882e(0.2879X) + 0.4388)0.9715−0.835
S56Y = 0.4829058/(0.5944e(0.275X) + 0.4586)0.8743−0.576
S28Y = 0.50284/(0.5565e(−0.2231X) + 0.4835)0.9411−0.285
S10Y = 0.5437773/(0.5721e(0.2231X) + 0.5049)0.82810.081
S21Y = 0.5490298/(0.5151e(0.2924X) + 0.5269)0.92470.353
S11Y = 0.5569336/(0.5256e(0.2513X) + 0.5284)0.91650.429
S006Y = 0.6057768/(0.4544e(0.207X) + 0.5836)0.93581.562
S27Y = 0.7050042/(0.4224e(0.1686X) + 0.6546)0.86353.447
Table 5. Stolon regrowth ability post-low-temperature treatment.
Table 5. Stolon regrowth ability post-low-temperature treatment.
NameRegrowth Ratio (%)Relative Regrowth Rate (%)Total Relative Regrowth Rate (%)
8 °C3 °C−2 °C−7 °C−12 °C3 °C2 °C −7 °C
S3046.000 ± 0.033abc36.000 ± 0.033bc26.000 ± 0.033ab10.000 ± 0.000a0.000 ± 0.00078.000 ± 0.032cd57.000 ± 0.054abc22.000 ± 0.021a52.000 ± 0.058a
S3950.000 ± 0.057ab40.000 ± 0.100ab26.000 ± 0.066ab10.000 ± 0.100a0.000 ± 0.00080.000 ± 0.036bc52.000 ± 0.045bcdef20.000 ± 0.036ab51.000 ± 0.014ab
S2540.000 ± 0.100cd36.000 ± 0.033bc20.000 ± 0.000abcd3.000 ± 0.033ab0.000 ± 0.00090.000 ± 0.052a50.000 ± 0.078cdefg8.000 ± 0.069abc49.000 ± 0.064bc
S5540.000 ± 0.000cd36.000 ± 0.066bc23.000 ± 0.033abc0.000 ± 0.000b0.000 ± 0.00090.000 ± 0.032a58.000 ± 0.021ab0.000 ± 0.031c49.000 ± 0.036bc
S1353.000 ± 0.033a46.000 ± 0.033a26.000 ± 0.088ab3.000 ± 0.033ab0.000 ± 0.00087.000 ± 0.058ab49.000 ± 0.065defg6.000 ± 0.066bc47.000 ± 0.067c
41036446.000 ± 0.088abc36.000 ± 0.033bc26.000 ± 0.066ab3.000 ± 0.033ab0.000 ± 0.00078.000 ± 0.088cd57.000 ± 0.021abc7.000 ± 0.025abc47.000 ± 0.065c
S1450.000 ± 0.057ab40.000 ± 0.056ab30.000 ± 0.057a0.000 ± 0.000b0.000 ± 0.00080.000 ± 0.065bc60.000 ± 0.054a0.000 ± 0.000c47.000 ± 0.069c
S3130.000 ± 0.033ef26.000 ± 0.033def16.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00087.000 ± 0.037ab53.000 ± 0.088abcde0.000 ± 0.000c47.000 ± 0.056c
S2250.000 ± 0.057ab40.000 ± 0.056ab20.000 ± 0.032abcd6.000 ± 0.033ab0.000 ± 0.00080.000 ± 0.041bc40.000 ± 0.056hijk12.000 ± 0.032abc44.000 ± 0.044d
674925-146.000 ± 0.066abc30.000 ± 0.098cde20.000 ± 0.057abcd10.000 ± 0.100a0.000 ± 0.00065.000 ± 0.012ghi43.000 ± 0.032ghij22.000 ± 0.021a43.000 ± 0.021d
29159430.000 ± 0.000ef26.000 ± 0.088def13.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00087.000 ± 0.037ab43.000 ± 0.036ghij0.000 ± 0.000c43.000 ± 0.032d
S5830.000 ± 0.057ef23.000 ± 0.033efg16.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00077.000 ± 0.077cde53.000 ± 0.088abcde0.000 ± 0.000c43.000 ± 0.032d
ST00340.000 ± 0.100cd36.000 ± 0.033bc16.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00090.000 ± 0.032a40.000 ± 0.022hijk0.000 ± 0.000c43.000 ± 0.024d
674925-336.000 ± 0.066de26.000 ± 0.033def20.000 ± 0.057abcd0.000 ± 0.000b0.000 ± 0.00072.000 ± 0.032def56.000 ± 0.032abcd0.000 ± 0.000c43.000 ± 0.024d
S00630.000 ± 0.000ef20.000 ± 0.023fh16.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00067.000 ± 0.054fghi53.000 ± 0.088abcde0.000 ± 0.000c40.000 ± 0.054e
41036343.000 ± 0.066bcd30.000 ± 0.100cde20.000 ± 0.057abcd0.000 ± 0.000b0.000 ± 0.00070.000 ± 0.035efgh47.000 ± 0.023efgh0.000 ± 0.000c39.000 ± 0.054ef
S5626.000 ± 0.033fg20.000 ± 0.100fh10.000 ± 0.057bcde0.000 ± 0.000b0.000 ± 0.00077.000 ± 0.078cd38.000 ± 0.041ijkl0.000 ± 0.000c38.000 ± 0.045efg
S00550.000 ± 0.100ab33.000 ± 0.033bcd23.000 ± 0.033abc0.000 ± 0.000b0.000 ± 0.00066.000 ± 0.065fghi46.000 ± 0.054fgh0.000 ± 0.000c37.000 ± 0.023fg
S4750.000 ± 0.100ab36.000 ± 0.133bc20.000 ± 0.100abcd0.000 ± 0.000b0.000 ± 0.00072.000 ± 0.033defg40.000 ± 0.022hijk0.000 ± 0.000c37.000 ± 0.065fg
G00130.000 ± 0.320ef23.000 ± 0.088efg10.000 ± 0.057bcde0.000 ± 0.000b0.000 ± 0.00077.000 ± 0.057cde33.000 ± 0.014klm0.000 ± 0.000c37.000 ± 0.047fg
S5036.000 ± 0.066de26.000 ± 0.033def13.000 ± 0.066abcde0.000 ± 0.000b0.000 ± 0.00072.000 ± 0.023def36.000 ± 0.036kl0.000 ± 0.000c36.000 ± 0.054g
S5136.000 ± 0.066de26.000 ± 0.033def13.000 ± 0.066abcde0.000 ± 0.000b0.000 ± 0.00072.000 ± 0.054def36.000 ± 0.054kl0.000 ± 0.000c36.000 ± 0.054g
S5430.000 ± 0.054ef26.000 ± 0.033def6.666 ± 0.033cde0.000 ± 0.000b0.000 ± 0.00087.000 ± 0.036ab20.000 ± 0.059n0.000 ± 0.000c36.000 ± 0.064g
S0236.000 ± 0.133de26.000 ± 0.066def10.000 ± 0.057bcde0.000 ± 0.000b0.000 ± 0.00072.000 ± 0.023def28.000 ± 0.023m0.000 ± 0.000c33.000 ± 0.033h
S0836.000 ± 0.033de30.000 ± 0.098cde6.000 ± 0.066cde0.000 ± 0.000b0.000 ± 0.00083.000 ± 0.054abc17.000 ± 0.032n0.000 ± 0.000c33.000 ± 0.057h
S2336.000 ± 0.066de26.000 ± 0.066def10.000 ± 0.057bcde0.000 ± 0.000b0.000 ± 0.00072.000 ± 0.023def28.000 ± 0.036m0.000 ± 0.000c33.000 ± 0.036h
S3720.000 ± 0.021g10.000 ± 0.021h10.000 ± 0.100bcde0.000 ± 0.000b0.000 ± 0.00050.000 ± 0.054m50.000 ± 0.078cdefg0.000 ± 0.000c33.000 ± 0.035h
S4436.000 ± 0.033de20.000 ± 0.100fh16.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00056.000 ± 0.036klm44.000 ± 0.064ghi0.000 ± 0.000c33.000 ± 0.025h
S4830.000 ± 0.057ef20.000 ± 0.000fh10.000 ± 0.054bcde0.000 ± 0.000b0.000 ± 0.00067.000 ± 0.023fghi33.000 ± 0.014klm0.000 ± 0.000c33.000 ± 0.014h
30013043.000 ± 0.033bcd26.000 ± 0.066def16.000 ± 0.088abcd0.000 ± 0.000b0.000 ± 0.00060.000 ± 0.036ijk37.000 ± 0.056jkl0.000 ± 0.000c33.000 ± 0.025h
41036136.000 ± 0.033de20.000 ± 0.057fh13.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00056.000 ± 0.021klm36.000 ± 0.032kl0.000 ± 0.000c31.000 ± 0.023hi
S2936.000 ± 0.033de20.000 ± 0.100fh13.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00056.000 ± 0.025klm36.000 ± 0.025kl0.000 ± 0.000c31.000 ± 0.065hi
S4936.000 ± 0.133de20.000 ± 0.023fh13.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00056.000 ± 0.025klm36.000 ± 0.021kl0.000 ± 0.000c31.000 ± 0.021hi
50903846.000 ± 0.033abc26.000 ± 0.033def16.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00057.000 ± 0.065klm35.000 ± 0.057kl0.000 ± 0.000c30.000 ± 0.035hij
S4646.000 ± 0.066abc26.000 ± 0.088def16.000 ± 0.088abcde0.000 ± 0.000b0.000 ± 0.00057.000 ± 0.041klm35.000 ± 0.36kl0.000 ± 0.000c30.000 ± 0.025hij
S5740.000 ± 0.100cd23.000 ± 0.033efg13.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00058.000 ± 0.023jkl33.000 ± 0.014lm0.000 ± 0.000c30.000 ± 0.054hij
674924-236.000 ± 0.033de26.000 ± 0.133def6.000 ± 0.066cde0.000 ± 0.000b0.000 ± 0.00072.000 ± 0.045def17.000 ± 0.025n0.000 ± 0.000c30.000 ± 0.036hij
S00430.000 ± 0.000ef16.000 ± 0.033g10.000 ± 0.057bcde0.000 ± 0.000b0.000 ± 0.00053.000 ± 0.069lm33.000 ± 0.045klm0.000 ± 0.000c29.000 ± 0.031ij
S0130.000 ± 0.000ef16.000 ± 0.033g10.000 ± 0.057bcde0.000 ± 0.000b0.000 ± 0.00053.000 ± 0.047lm33.000 ± 0.025klm0.000 ± 0.000c29.000 ± 0.025ij
S2130.000 ± 0.000ef20.000 ± 0.013fh6.000 ± 0.033cde0.000 ± 0.000b0.000 ± 0.00067.000 ± 0.014fghi20.000 ± 0.056n0.000 ± 0.000c29.000 ± 0.021ij
S2630.000 ± 0.000ef16.000 ± 0.033g10.000 ± 0.000bcde0.000 ± 0.000b0.000 ± 0.00053.000 ± 0.021lm33.000 ± 0.014klm0.000 ± 0.000c29.000 ± 0.021ij
S3830.000 ± 0.100ef20.000 ± 0.023fh6.000± 0.033cde0.000 ± 0.000b0.000 ± 0.00067.000 ± 0.023fghi20.000 ± 0.056n0.000 ± 0.000c29.000 ± 0.023ij
S5230.000 ± 0.100ef16.000 ± 0.033g10.000 ± 0.023bcde0.000 ± 0.000b0.000 ± 0.00053.000 ± 0.056lm33.000 ± 0.014klm0.000 ± 0.000c29.000 ± 0.025ij
647924-236.000 ± 0.033de16.000 ± 0.033g13.000 ± 0.033abcde0.000 ± 0.000b0.000 ± 0.00044.000 ± 0.025m36.000 ± 0.054kl0.000 ± 0.000c27.000 ± 0.014j
S5340.000 ± 0.052cd16.000 ± 0.033g16.000 ± 0.066abcde0.000 ± 0.000b0.000 ± 0.00040.000 ± 0.036mn40.000 ± 0.036hijk0.000 ± 0.000c27.000 ± 0.036j
S6220.000 ± 0.021g16.000 ± 0.033g0.000 ± 0.000e0.000 ± 0.000b0.000 ± 0.00080.000 ± 0.054bc0.000 ± 0.000p0.000 ± 0.000c27.000 ± 0.054j
S00736.000 ± 0.033de16.000 ± 0.033g10.000 ± 0.100bcde0.000 ± 0.000b0.000 ± 0.00044.000 ± 0.023m28.000 ± 0.025m0.000 ± 0.000c24.000 ± 0.021k
S1236.000 ± 0.133de23.000 ± 0.066efg3.000 ± 0.033de0.000 ± 0.000b0.000 ± 0.00064.000 ± 0.036hij8.000 ± 0.036o0.000 ± 0.000c24.000 ± 0.036k
S2830.000 ± 0.054ef20.000 ± 0.045fh0.000 ± 0.000e0.000 ± 0.000b0.000 ± 0.00067.000 ± 0.025fghi0.000 ± 0.000p0.000 ± 0.000c22.000 ± 0.000k
S4530.000 ± 0.100ef20.000 ± 0.100fh0.000 ± 0.000e0.000 ± 0.000b0.000 ± 0.00067.000 ± 0.056fghi0.000 ± 0.000p0.000 ± 0.000c22.000 ± 0.056k
S0440.000 ± 0.052cd20.000 ± 0.000fh6.000 ± 0.033cde0.000 ± 0.000b0.000 ± 0.00050.000 ± 0.054m15.000 ± 0.025n0.000 ± 0.000c22.000 ± 0.021k
S1126.000 ± 0.066fg16.000 ± 0.033g0.000 ± 0.000e0.000 ± 0.000b0.000 ± 0.00062.000 ± 0.023ijk0.000 ± 0.000p0.000 ± 0.000c21.000 ± 0.023k
S2726.000 ± 0.066fg16.000 ± 0.033g0.000 ± 0.000e0.000 ± 0.000b0.000 ± 0.00062.000 ± 0.056ijk0.000 ± 0.000p0.000 ± 0.000c21.000 ± 0.056k
S1026.000 ± 0.066fg13.000 ± 0.033gh0.000 ± 0.000e0.000 ± 0.000b0.000 ± 0.00050.000 ± 0.054m0.000 ± 0.000p0.000 ± 0.000c17.000 ± 0.054l
30012926.000 ± 0.120fg10.000 ± 0.000h0.000 ± 0.000e0.000 ± 0.000b0.000 ± 0.00038.000 ± 0.000n0.000 ± 0.000p0.000 ± 0.000c13.000 ± 0.000m
Note: The significant differences among accessions in a same column is indicated by different letters.
Table 6. Membership function analysis based on laboratory results. The significant differences among accessions in a same column is indicated by different letters.
Table 6. Membership function analysis based on laboratory results. The significant differences among accessions in a same column is indicated by different letters.
AccessionLT50Total Relative Regrowth RateScoreRank
S391.000 ± 0.0000.974 ± 0.014ab0.987 ± 0.007a1
S300.863 ± 0.0001.000 ± 0.000a0.931 ± 0.000b2
S250.899 ± 0.0000.923 ± 0.001bc0.911 ± 0.001bc3
4103640.947 ± 0.0000.871 ± 0.026c0.909 ± 0.013bc4
S550.841 ± 0.0000.922 ± 0.026bc0.881 ± 0.013cd5
S140.852 ± 0.0000.872 ± 0.023c0.862 ± 0.011d6
S130.852 ± 0.0000.872 ± 0.012c0.862 ± 0.006d7
674925-10.943 ± 0.0000.768 ± 0.031d0.856 ± 0.015d8
S220.906 ± 0.0000.795 ± 0.022d0.851 ± 0.011d9
S0050.954 ± 0.0000.616 ± 0.023fg0.785 ± 0.011e10
S310.505 ± 0.0000.871 ± 0.031c0.688 ± 0.015f11
S470.748 ± 0.0000.615 ± 0.005fg0.681 ± 0.002fg12
S580.561 ± 0.0000.771 ± 0.062d0.666 ± 0.031fg13
ST0030.561 ± 0.0000.769 ± 0.003d0.665 ± 0.001fg14
674925-30.554 ± 0.0000.769 ± 0.023d0.661 ± 0.011fg15
4103630.635 ± 0.0000.667 ± 0.024ef0.651 ± 0.012g16
5090380.785 ± 0.0000.436 ± 0.019ijk0.611 ± 0.009h17
2915940.441 ± 0.0000.768 ± 0.041d0.604 ± 0.021h18
G0010.577 ± 0.0000.615 ± 0.021fg0.596 ± 0.011h19
S460.740 ± 0.0000.435 ± 0.008ijk0.587 ± 0.004h20
S510.573 ± 0.0000.591 ± 0.023g0.581 ± 0.011hi21
3001300.597 ± 0.0000.512 ± 0.012h0.555 ± 0.006ij22
S570.627 ± 0.0000.436 ± 0.018ijk0.531 ± 0.009jk23
S020.527 ± 0.0000.512 ± 0.012h0.521 ± 0.006jkl24
S440.501 ± 0.0000.513 ± 0.021hi0.507 ± 0.011klm25
S480.501 ± 0.0000.512 ± 0.007hi0.506 ± 0.003klm26
S230.489 ± 0.0000.513 ± 0.022hi0.501 ± 0.011klmn27
S540.404 ± 0.0000.590 ± 0.021g0.497 ± 0.011klmn28
S490.493 ± 0.0000.486 ± 0.007hij0.491 ± 0.003lmno29
S080.463 ± 0.0000.512 ± 0.007hi0.487 ± 0.003lmno30
S290.512 ± 0.0000.462 ± 0.021hijk0.487 ± 0.011lmno31
4103610.505 ± 0.0000.461 ± 0.007hijk0.483 ± 0.003mnopq32
S260.519 ± 0.0000.436 ± 0.018ijk0.478 ± 0.009mnopq33
S560.315 ± 0.0000.641 ± 0.005efg0.478 ± 0.002mnopq34
674924-20.493 ± 0.0000.435 ± 0.012ijk0.464 ± 0.006nopqr35
S500.335 ± 0.0000.589 ± 0.006g0.462 ± 0.003nopqr36
647924-20.546 ± 0.0000.359 ± 0.017l0.453 ± 0.008opqrs37
S010.493 ± 0.0000.410 ± 0.021jkl0.452 ± 0.011pqrs38
S520.484 ± 0.0000.411 ± 0.018kl0.447 ± 0.009qrs39
S0040.461 ± 0.0000.410 ± 0.018kl0.435 ± 0.009rst40
S380.434 ± 0.0000.435 ± 0.012ijk0.434 ± 0.006rst41
S370.345 ± 0.0000.513 ± 0.021hi0.429 ± 0.011rst42
S0060.147 ± 0.0000.693 ± 0.071e0.420 ± 0.035st43
S530.446 ± 0.0000.358 ± 0.013l0.402 ± 0.006tu44
S040.528 ± 0.0000.231 ± 0.003m0.379 ± 0.001uv45
S620.384 ± 0.0000.358 ± 0.009l0.371 ± 0.004uv46
S0070.439 ± 0.0000.283 ± 0.033m0.361 ± 0.016v47
S120.424 ± 0.0000.281 ± 0.013m0.353 ± 0.006vw48
S210.242 ± 0.0000.410 ± 0.012kl0.326 ± 0.006w49
S450.401 ± 0.0000.231 ± 0.011m0.315 ± 0.005w50
S280.292 ± 0.0000.231 ± 0.017m0.261 ± 0.008x51
S110.236 ± 0.0000.205 ± 0.003m0.221 ± 0.001xy52
3001290.385 ± 0.0000.000 ± 0.000o0.192 ± 0.000y53
S100.263 ± 0.0000.102 ± 0.001n0.183 ± 0.001y54
S270.000 ± 0.0000.346 ± 0.182m0.173 ± 0.091y55
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Qu, J.; Hao, D.-L.; Zhou, J.-Y.; Chen, J.-B.; Sun, D.-J.; Liu, J.-X.; Zong, J.-Q.; Wang, Z.-Y. Evaluating the Cold Tolerance of Stenotaphrum Trin Plants by Integrating Their Performance at Both Fall Dormancy and Spring Green-Up. Horticulturae 2024, 10, 761. https://doi.org/10.3390/horticulturae10070761

AMA Style

Qu J, Hao D-L, Zhou J-Y, Chen J-B, Sun D-J, Liu J-X, Zong J-Q, Wang Z-Y. Evaluating the Cold Tolerance of Stenotaphrum Trin Plants by Integrating Their Performance at Both Fall Dormancy and Spring Green-Up. Horticulturae. 2024; 10(7):761. https://doi.org/10.3390/horticulturae10070761

Chicago/Turabian Style

Qu, Jia, Dong-Li Hao, Jin-Yan Zhou, Jing-Bo Chen, Dao-Jin Sun, Jian-Xiu Liu, Jun-Qin Zong, and Zhi-Yong Wang. 2024. "Evaluating the Cold Tolerance of Stenotaphrum Trin Plants by Integrating Their Performance at Both Fall Dormancy and Spring Green-Up" Horticulturae 10, no. 7: 761. https://doi.org/10.3390/horticulturae10070761

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