莲雾开花对喷施氯吡硫磷的生理响应以及转录组分析

doi:10.16420/j.issn.0513-353x.2024-0645

摘要/Abstract

摘要： 莲雾生产中“乐斯本”是主要的催花药剂（主要成分氯吡硫磷）。以‘印度红’莲雾为试验材料，探究喷施氯吡硫磷对莲雾成花枝率和花穗数量，叶片丙二醛（MDA）、抗坏血酸（AsA）、还原型谷胱甘肽（GSH）、可溶性蛋白含量，超氧化物歧化酶（SOD）和过氧化物酶（POD）活性的影响；同时进行了转录组分析。结果表明，喷施1.67 g · L^-1氯吡硫磷对‘印度红’莲雾开花起促进作用。氯吡硫磷处理的叶片中SOD和POD活性增强，AsA、GSH和可溶性蛋白含量有所增加。转录组分析结果显示，差异表达基因主要富集在光系统、光合膜等方面，涉及光合作用通路。共选出27个关键差异表达基因，8个与呼吸作用相关、4个与光合作用相关、3个与碳水化合物相关、2个与成花相关、4个与水杨酸相关、1个与生长素相关、3个与脱落酸相关、2个与氧化还原平衡相关。通过构建偏最小二乘结构方程建模（PLS-SEM），发现大部分变量显著相关。氧化还原平衡模块与成花诱导模块之间存在正向关系，其模块中正向调控的关键差异表达基因SsHTH和SsOxr1在莲雾成花诱导过程中起重要的作用。

关键词: 莲雾, 氯吡硫磷, 催花, 抗氧化系统, 转录组分析

Abstract:

Lorsban（active ingredient：chlorpyrifos）serves as a primary flowering inducing agent in wax apple production. The effects of chlorpyrifos spray on flowering branch rate and inflorescence number in wax apple‘Yinduhong’were investigated. Physiological responses were assessed by measuring the content of malondialdehyde（MDA），ascorbic acid（AsA）and reduced glutathione（GSH），soluble proteins，as well as superoxide dismutase（SOD）and peroxidase（POD）activities. Concurrently，transcriptome sequencing was performed to analyze gene expression changes under chlorpyrifos treatment. The results showed that foliar application of 1.67 g · L^-1 chlorpyrifos significantly promoted flowering in‘Yinduhong’wax apple. Concurrently，the activity of antioxidant enzymes（SOD and POD）and the content of ascorbic acid（AsA），reduced glutathione（GSH），and soluble proteins in the leaves increased. Transcriptome analysis revealed that differentially expressed genes（DEGs）were primarily enriched in photosystems and photosynthetic membranes，involving photosynthesis pathways. Among 27 key DEGs identified，8 were related to respiration，4 to photosynthesis，3 to carbohydrate metabolism，2 to flowering regulation，4 to salicylic acid pathway，1 to auxin signaling，3 to abscisic acid response，and 2 to redox homeostasis. Partial least squares structural equation modeling（PLS-SEM）demonstrated significant correlations among most variables. Module analysis indicated a positive relationship between the redox homeostasis module and flowering induction module，with two key DEGs（SsHTH and SsOxr1）in these modules showing positive regulation and playing crucial roles in wax apple flowering induction.

Key words: wax apple, chlorpyrifos, flower induction, antioxidant system, transcriptome analysis

孙东宇, 魏冬, 杨胤延, 胡彩珠, 胡志群, 周东辉, 周碧燕. 莲雾开花对喷施氯吡硫磷的生理响应以及转录组分析[J]. 园艺学报, 2025, 52(7): 1718-1732.

SUN Dongyu, WEI Dong, YANG Yinyan, HU Caizhu, HU Zhiqun, ZHOU Donghui, and ZHOU Biyan. Physiological Response and Transcriptome Analysis of Wax Apple Flowering to Foliar Application of Chlorpyrifos[J]. Acta Horticulturae Sinica, 2025, 52(7): 1718-1732.

图/表 10

表1 qRT-PCR分析中使用的引物

Table 1 Primers used in qRT-PCR analysis

引物名称 Primer name	上游引物（5′-3′） Forward primer	下游引物（5′-3′） Reverse primer
β-actin	CTCAATCCCAAGGCGAATA	ACGACCACTGGCATAAAGG
qSsCUT1	ACCACATTATCCCCCTCACC	CATCTGGAACTCGACGCTCT
qSsAlb	TCAAGAAGGCACCCCGATTA	CACCAGGGACCCACTACAGC
qSsBCB	GGCGGAGTAGTGTAGAGATT	CTATGGGTGATGATGAGGAG
qSsHTH	TGGACCGTGGCAAATAAGTA	GCAGATGTCAGCCCGAACTC
qSsACT1	GTTGTCGCACACGATAGGTT	CAAATGGCTGATGAGGATGT
qSsPNC1	TTCCCACAGTTCTTCCTAAT	CGACAACAATCTCTCTCCTC
qSsGOLS2	TGCGAGAAGACATGGAGCCA	ACCGATTTCATACTGAGGGG
qSsARAC7	CAGTATCCCACAATCCCAAG	ACACCAGCAACAAGTTCCCT

表2 喷施氯吡硫磷对莲雾开花效果的影响

Table 2 The effect of spraying chlorpyrifos on the flowering of wax apple

处理 Treatment	花穗总数 Number of whole flowering spikes	成花枝率/% Flower branch rate
水H₂O（对照Control）	28.0 ± 2.2	35.0 ± 1.4
氯吡硫磷Chlorpyrifos	78.4 ± 5.1 ^***	68.0 ± 4.3 ^***

图1 喷施氯吡硫磷对莲雾MAD、AsA、GSH、可溶性蛋白含量以及SOD、POD活性的影响样品在喷施氯吡硫磷处理后的13 d观察到了花芽，而清水对照处理后20 d没有观察到花芽。独立样本t检验，* P ≤ 0.05，** P ≤ 0.01，*** P ≤ 0.001，n = 5

Fig. 1 Effects of MAD，AsA，GSH，soluble proteins content，and SOD，POD activities of chlorpyrifos spraying on wax apple After 13 days of chlorpyrifos treatment，flower buds were observed，while no flower buds were observed after 20 days of water spray treatment. Independent sample t-test，* P ≤ 0.05，** P ≤ 0.01，*** P ≤ 0.001，n = 5

表3 氯吡硫磷喷施莲雾催花的转录组测序统计结果（质控）

Table 3 Transcriptional sequencing statistical results (quality control) of chlorpyrifos spray on wax apple flowering

样品 Sample	清洁读取数量 Clean reads	鸟嘌呤和胞嘧啶的含量百分比/% GC	质量分数大于等于20的碱基比例/% Q20	质量分数大于等于30的碱基比例/% Q30
L0-1	25 789 836	52.98	98.64	95.70
L0-2	23 913 102	53.08	98.53	95.41
LC1-1	24 353 062	53.80	98.35	95.03
LC1-2	25 939 216	53.75	98.31	94.91
LT1-1	23 117 038	53.76	98.32	94.95
LT1-2	21 600 592	53.78	98.20	94.66
LC2-1	21 019 944	53.83	98.35	95.01
LC2-2	21 746 492	54.09	98.62	95.61
LT2-1	22 263 240	53.77	98.30	94.88
LT2-2	25 333 724	54.05	98.58	95.52

图2 氯吡硫磷喷施莲雾催花的转录组差异表达基因数 L0、LC1、LT1、LC2和LT2分别表示喷施氯吡硫磷和清水（对照）后0、1、4 d的叶片样品。下同

Fig. 2 Number of differentially expressed genes in wax apple transcriptome induced by chlorpyrifos spray for flowering L0，LC1，LT1，LC2，and LT2 represent leaf samples collected at 0，1，and 4 days after treatment with chlorpyrifos or water（control），respectively. The same below

图3 LC1 vs. LT1和 LC2 vs. LT2比较组中GO功能富集分析结果（前10项）

Fig. 3 Top 10 results of GO enrichment analysis for the comparison between LC1 vs. LT1 and LC2 vs. LT2 groups

图4 LC1 vs. LT1和 LC2 vs. LT2比较组中KEGG通路富集分析结果（前10项）

Fig. 4 Top 10 results of KEGG pathway enrichment analysis for the comparison between LC1 vs. LT1 and LC2 vs. LT2 groups

图5 氯吡硫磷喷施对莲雾催花的差异基因的热图

Fig. 5 Heatmap of differential genes in wax apple induced flowering by chlorpyrifos spraying

图6 qRT-PCR和RNA-Seq基因表达水平的热图

Fig. 6 Heatmap of test gene expression levels shown using quantitative real-time RT-PCR（qRT-PCR）and RNA sequencing（RNA-Seq）

图7 氯吡硫磷喷施莲雾催花差异表达基因的共表达网络偏最小二乘结构方程建模图（PLS-SEM）。中心部分是成花诱导模块以及氧化还原平衡模块，其余模块均是与成花诱导过程有密切联系的生理过程以及相关激素。路径系数的正负表示模块与模块间以及基因与模块间正负调控关系。箭头的宽度反映了各因子间密切程度的绝对值大小，箭头上的数值表示该途径的因子负荷强度，数值越大表明密切程度越大。从成花诱导模块到氧化还原平衡模块、光合作用模块、呼吸作用模块等的路径是一级通路，而从成花诱导模块、氧化还原平衡模块、光合作用模块、呼吸作用模块等到各类基因的路径则是二级通路

Fig. 7 The co-expression network of differentially expressed genes in wax apple induced by chlorpyrifos spraying for flowering Partial Least Squares Structural Equation Modeling（PLS-SEM）diagram. The central part of this diagram consists of the flowering induction module and the redox balance module，while the remaining modules are physiological processes and related hormones closely associated with the flowering induction process. The positive or negative path coefficients represent the positive or negative regulatory relationships between modules and between genes and modules. The width of the arrows reflects the absolute value of the closeness between factors，with the values on the arrows indicating the strength of factor loading for that pathway；larger values denote greater closeness. In the diagram，the pathways from the flowering induction module to the redox balance module，photosynthesis module，respiration module，and other modules form the primary pathways，while the pathways from the flowering induction module，redox balance module，photosynthesis module，respiration module，and other modules to various genes constitute the secondary pathways

参考文献 41

[1]	Beauchamp C, Fridovich I. 1971. Superoxide dismutase:improved assays and an assay applicable to acrylamide gels. Analytical Biochemistry, 44 (1).
[2]	Chen Jianwei, Kang Xiaomei, Cai Yiwei, Li Shujun, Cheng Guangyou. 2023. Observation of growth rhythm and flowering and fruiting process of Quercus mongolica. Journal of beihua university(Natural Science), 24 (6):737-743. (in Chinese)
	陈建伟, 康晓梅, 蔡艺玮, 李树君, 程广有. 2023. 蒙古栎生长节律及开花结实过程观测. 北华大学学报(自然科学版), 24 (6):737-743.
[3]	Chen Peng, Yan Longxiang, Huang Kai, Pei Tong, Li Dan, Yu Gaobo. 2017. Effects of four pesticides on GSH-ASA antioxidant system in tomato leaves. Guizhou Agricultural Sciences, 45 (2):36-41. (in Chinese)
	陈鹏, 闫龙祥, 黄凯, 裴童, 李丹, 于高波. 2017. 4种杀虫剂对番茄叶片GSH-ASA抗氧化系统的影响. 贵州农业科学, 45 (2):36-41.
[4]	Chen S, Tsai H, Raghu R, Do Y, Huang P. 2011. cDNA cloning and functional characterization of ETHYLENE INSENSITIVE 3 orthologs from Oncidium Gower Ramsey involved in flower cutting and pollinia cap dislodgement. Plant Physiology and Biochemistry, 49 (10):1209-1219.
[5]	Cheng H, Pan G, Zhou N, Zhai Z, Yang L, Zhu H, Cui X, Zhao P, Zhang H, Li S, Yang B, Jiang Y. 2022. Calcium-dependent Protein Kinase 5(CPK5)positively modulates drought tolerance through phosphorylating ABA-Responsive Element Binding Factors in oilseed rape(Brassica napus L.). Plant Science,315:111125.
[6]	Deng Renju. 2015. Physiological responses of pitaya to chilling stress and cold-tolerant mutant induction in vitro[Ph. D. Dissertation]. Sichuan: Sichuan Agricultural University. (in Chinese)
	邓仁菊. 2015. 火龙果对低温胁迫的生理响应及离体诱变筛选抗寒突变体研究[博士论文]. 四川: 四川农业大学.
[7]	Gao Jixia, Gong Chunmei, Liu Xiping. 2010. Influence of different water stress to glutathione antioxidant defense system in Robinia pseudoacacia. Acta Botanica Boreali-Occidentalia Sinica, 30 (7):1409-1414. (in Chinese)
	高吉霞, 龚春梅, 刘西平. 2010. 水分胁迫对刺槐叶和根谷胱甘肽抗氧化系统的影响. 西北植物学报, 30 (7):1409-1414.
[8]	Guo Chunxiao, Tian Subo, Zheng Chengshu, Wang Wenli, Sun Xianzhi. 2009. FT gene of flowering determination of plants in photoperiod pathway. Genomics and Applied Biology, 28 (3):613-618. (in Chinese)
	郭春晓, 田素波, 郑成淑, 王文莉, 孙宪芝. 2009. 光周期途径植物开花决定关键基因FT. 基因组学与应用生物学, 28 (3):613-618.
[9]	Harrison P J, Chandler J, Thompson A J, Bugg T D H. 2024. In vitro assay and inhibition of 9-cis-epoxycarotenoid dioxygenase(NCED)from Solanum lycopersicum and Zea mays. Methods in Enzymology,704:291-312.
[10]	Holm M, Ma L, Qu L, Deng X. 2002. Two interacting bZIP proteins are direct targets of COP1-mediated control of light-dependent gene expression in Arabidopsis. Genes & Development, 16 (10):1247-1259.
[11]	Hu C Z, Sun D Y, Yu J H, Chen M Q, Xue Y X, Wang J M, Su W, Chen R Y, Ali A, Song S W. 2024. Transcriptome analysis of intermittent light induced early bolting in flowering Chinese cabbage. Plants,13:13886.
[12]	Huang Sheng, Chen Xiongjin. 2016. Measures to advance florescence and regulate yield of Syzygium samarangense. Tropical Agricultural Engineering, 40 (2):38-41. (in Chinese)
	黄胜, 陈雄进. 2016. 促进莲雾提早开花调节产期措施研究. 热带农业工程, 40 (2):38-41.
[13]	Jin Zhou, Lu Shan, Jiang Junhao, Li Shouren, Zhang Nan, Jiang Xiaoyu, Wu Fan. 2023. Research progress on influencing factors and mechanisms of flower bud differentiation in horticultural plants. Acta Horticulturae Sinica, 50 (5):1151-1164. (in Chinese) doi: 10.16420/j.issn.0513-353x.2022-0058
	金洲, 卢山, 江俊浩, 李寿仁, 张楠, 江晓钰, 吴凡. 2023. 园艺植物花芽分化影响因素及机理研究进展. 园艺学报, 50 (5):1151-1164. doi: 10.16420/j.issn.0513-353x.2022-0058
[14]	Kong F, Liu B, Xia Z, Sato S, Bo M K. 2017. Two coordinately regulated homologs of FLOWERING LOCUS T are involved in the control of photoperiodic flowering in soybean. Plant Physiology, 154 (3):1220-1231.
[15]	Leonardo J, Julie M P, John J H. 2019. Central role of the LEAFY COTYLEDON1 transcription factor in seed development. Journal of Integrative Plant Biology, 61 (5):564-580. doi: 10.1111/jipb.12806
[16]	Li J, Chen Y, Wang L, Li D, Liu L, Li M. 2024a. An ethylene response factor AcERF 116 identified from A. catechu is involved in fruitlet abscission. Plant Science,344:112091.
[17]	Li S, He Y, Li D, Shi S, Wang Y, Tang X, Ge H, Liu Y, Chen H. 2024b. Fine mapping an AUXIN RESPONSE FACTOR,SmARF18,as a candidate gene of the PRICKLE LOCUS that controls prickle absence/presence on various organs in eggplant(Solanum melongena L.). Scientia Horticulturae,327:112874.
[18]	Lu B, Wang S, Feng H, Wang J, Zhang K, Li Y, Wu P, Zhang M, Xia Y, Peng C, Li C. 2024. FERONIA-mediated TIR1/AFB 2 oxidation stimulates auxin signaling in Arabidopsis. Molecular Plant, 17 (5):772-787.
[19]	Peng D, Qu G, Li H, Xie Y, Wu H, Yu L, Xie Y, Meng Z, Liu Z, Peng N, Saniboere B, Zhou B. 2024. Identification and analysis of gibberellin 2-oxidase(GA2ox)members in Cunninghamia lanceolate and the negative regulatory character of ClGA2ox12 in tree stature and xylem lignin deposits. Industrial Crops and Products,221:119407.
[20]	Rathore R S, Mishra M, Pareek A, Singla-Pareek S L. 2024. Concurrent improvement of rice grain yield and abiotic stress tolerance by overexpression of cytokinin activating enzyme LONELY GUY(OsLOG). Plant Physiology and Biochemistry,211:108635.
[21]	Ren Maofei, Mao Guiling, Liu Shanzhen, Wang Weiqin, Zheng Huabin, Tang Qiyuan. 2023. Research progress on the effects of light quality on plant growth and development,photosynthesis,and carbon and nitrogen metabolism. Plant Physiology Journal, 59 (7):1211-1228. (in Chinese)
	任毛飞, 毛桂玲, 刘善振, 王慰亲, 郑华斌, 唐启源. 2023. 光质对植物生长发育、光合作用和碳氮代谢的影响研究进展. 植物生理学报, 59 (7):1211-1228.
[22]	Ryu M Y, Cho S K, Kim W T. 2009. RNAi suppression of RPN12a decreases the expression of type-A ARRs,negative regulators of cytokinin signaling pathway,in Arabidopsis. Molecules and Cells, 28 (4):375-382.
[23]	Safrany J, Haasz V, Mate Z, Ciolfi A, Feher B, Oravecz A, Stec A, Dallmann G, Morelli G, Ulm R, Nagy F. 2008. Identification of a novel cis-regulatory element for UV-B-induced transcription in Arabidopsis. Plant Journal, 54 (3):402-414.
[24]	Sharma S, Arpita K, Nirgude M, Srivastava H, Kumar K, Sreevathsa R, Bhattacharya R, Gaikwad K. 2024. Genomic insights into cytokinin oxidase/dehydrogenase(CKX)gene family,identification,phylogeny and synteny analysis for its possible role in regulating seed number in pigeonpea[Cajanus cajan(L.)Millsp.]. International Journal of Biological Macromolecules,227:134194.
[25]	Sun T. 2021. Novel nucleocytoplasmic protein O-fucosylation by SPINDLY regulates diverse developmental processes in plants. Current Opinion in Structural Biology,68:113-121.
[26]	Thelander M, Landberg K, Muller A, Cloarec G, Cunniffe N, Huguet S, Soubigou-Taconnat L, Brunaud V, Coudert Y. 2022. Apical dominance control by TAR-YUC-mediated auxin biosynthesis is a deep homology of land plants. Current Biology, 32 (17):3838-3846.
[27]	Wang Lan, Cai Qianhui. 2011. Effects of low temperature stress on superoxide dismutase(SOD)and peroxidase(POD)activities in rice seedlings during the seedling stage. Hunan Agricultural Sciences,(11):56-58,62. (in Chinese)
	王兰, 蔡千蕙. 2011. 低温胁迫对水稻苗期SOD、POD活性的影响. 湖南农业科学,(11):56-58,62.
[28]	Wang Xuekui. 2006. Principles and techniques of plant physiology and biochemistry experiments. Beijing: Higher Education Publishing House. (in Chinese)
	王学奎. 2006. 植物生理生化实验原理和技术. 北京: 高等教育出版社.
[29]	Wu Ying. 2016. Floral bud transcriptome sequencing and analysis on floral development regulation Mechanisms of Sapium sebiferum[Ph. D. Dissertation]. Anhui: University of Science and Technology of China. (in Chinese)
	吴影. 2016. 乌桕花芽转录组测序分析及花发育调控机制研究[博士论文]. 安徽: 中国科学技术大学.
[30]	Xu S, Zhang Y, Liang F, Yuan X, Jiang S, Niu S, Cui B. 2022. Transcriptome analysis provides insights into the role of phytohormones in regulating axillary bud development of flower stalk in Phalaenopsis. Scientia Horticulturae,306:111419.
[31]	Yan B, Yang Z, He G, Jing Y, Dong H, Ju L, Zhang Y, Zhu Y, Zhou Y, Sun J. 2021. The blue light receptor CRY 1 interacts with GID1 and DELLA proteins to repress gibberellin signaling and plant growth. Plant Communications, 6 (2):100245.
[32]	Yang Rongping, Chen Xian, Zhang Hong, Cheng Jinghui, Hu Xiaoxue, Li Wenxiang. 2009. Research progress of wax apple. China Fruit & Vegetable,(1):41-43. (in Chinese)
	杨荣萍, 陈贤, 张宏, 程竞卉, 胡晓雪, 李文祥. 2009. 莲雾研究进展. 中国果菜,(1):41-43.
[33]	Zegeye W A, Chen D, Islam M, Wang H, Riaz A, Rani M H, Hussain K, Liu Q, Zhan X, Cheng S, Cao L, Zhang Y. 2022. OsFBK4,a novel GA insensitive gene positively regulates plant height in rice(Oryza Sativa L.). Ecological Genetics and Genomics,23:100115.
[34]	Zhang Mengyun, Yuan Lingyun, Zhu Shidong, Hou Jinfeng, Hou Xilin, Liu Tongkun, Shan Guolei, Chen Guohu, Tang Xiaoyan, Wang Chenggang. 2024. Identification and bioinformatics analysis of antioxidant genes(OXR)in cruciferous plants. Molecular Plant Breeding, 22 (17):5610-5621. (in Chinese)
	张梦云, 袁凌云, 朱世东, 侯金锋, 侯喜林, 刘同坤, 单国雷, 陈国户, 唐小燕, 汪承刚. 2024. 十字花科植物抗氧化基因(OXR)的鉴定与生物信息学分析. 分子植物育种, 22 (17):5610-5621.
[35]	Zhang Y, Wang C, Huang M, Xiao J, Li X, Wang Y, Zhang D, Yang Y. 2024. RING-type E3 ligase PROTEOLYSIS1 from Syntrichia caninervis targets ABI3 for degradation and modulates plant stress responses. Environmental and Experimental Botany,226:105893.
[36]	Zhao Jingyi, Wu Xiaoxu, Hu Yunjie, Gai Shuting, Zhu Zhihao, Qin Lei, Wang Yong. 2024. Molecular cloning and functional analysis of AcGAI in onion flowering regulation. Acta Horticulturae Sinica, 51 (8):1792-1802. (in Chinese)
	赵静一, 吴小旭, 胡云捷, 盖淑婷, 朱志浩, 秦蕾, 王勇. 2024. 洋葱AcGAI的克隆及其在开花途径的功能分析. 园艺学报, 51 (8):1792-1802.
[37]	Zheng D, Hrazdina G. 2010. Cloning and characterization of an expansin gene,RiEXP1,and a 1-aminocyclopropane-1-carboxylic acid synthase gene,RiACS1 in ripening fruit of raspberry(Rubus idaeus L.). Plant Science, 179 (1-2):113-139.
[38]	Zheng Jiaxie, Zhou Hongling, Zhang Shaoping, Zheng Yunyun. 2016. Research on techniques for regulating the production period of wax apples in Zhangzhou. Journal of Fruit Science, 33 (12):1517-1522. (in Chinese)
	郑加协, 周红玲, 张少平, 郑云云. 2016. 漳州莲雾产期调节技术研究. 果树学报, 33 (12):1517-1522.
[39]	Zhong Zhong. 2003. Influence of different micro-fertilizers on florists cineraria blossom and fruiting. Anhui Agricultural Sciences,(5):838-839,845. (in Chinese)
	钟忠. 2003. 不同微肥对瓜叶菊开花和结果的影响. 安徽农业科学,(5):838-839,845.
[40]	Zhou Hongling, Zheng Jiaxie, Zeng Yurong, Chen Shi. 2010. Techniques for regulating the production period of wax apples and their applications in production. China Tropical Agriculture,(3):53-55. (in Chinese)
	周红玲, 郑加协, 曾玉荣, 陈石. 2010. 莲雾产期调节技术及其在生产上的应用. 中国热带农业,(3):53-55.
[41]	Zhu Panpan. 2017. Characterization and expression of genes involved in the abscisic acid biosynthesis and metabolism during ripening of mulberry fruit[M. D. Dissertation]. Chongqing: Southwest University. (in Chinese)
	朱攀攀. 2017. 桑树脱落酸生物合成及裂解相关基因的鉴定及在桑椹生长发育中的表达分析[硕士论文]. 重庆: 西南大学.