Cyclocarya paliurus (Batal.) Iljinsk is a multipurpose tree species with great potential for development. To identify indicators of grafting compatibility during the healing process, two cloned genotypes, CR4 and CR5, were used as scions, grafted onto seedling rootstocks derived from the Guangxi provenance. Following branch grafting, samples from the graft union were collected at 0, 20, 40, and 60 days. Physiological-biochemical indicators, including soluble sugars, soluble proteins, starch, peroxidase (POD) activity, polyphenol oxidase (PPO) activity, phenylalanine ammonia-lyase (PAL) activity, as well as flavonoid and phenylpropanoid contents, were analyzed. The graft survival rate of the CR4 combination (60%) was significantly higher than that of CR5 (35%). Significant differences in key physiological indicators were observed between the two scion-rootstock combinations. Analysis revealed that soluble sugar and soluble protein levels, along with POD and PAL activities in the scion during the early grafting stage, significantly influenced the final survival rate. Furthermore, lignans, lignin precursors, and several flavonoid compounds were found to accumulate preferentially at the graft union of the CR4 combination, which exhibited higher compatibility. These findings provide a physiological and biochemical foundation for selecting compatible scions and advancing clonal cultivation of C. paliurus.

Sapindus is an important forest tree genus with utility in biodiesel, biomedicine, biochemistry and forestry. Similar to many perennial crop plants, its breeding is hampered by long generation times and lack of genetic resources. To understand the genome evolution underlying the important bioeconomic traits, we carried out a common garden experiment with 100 Sapindus core germplasm individuals representing three endemic species and 60 populations sampled throughout China. Whole genome sequencing identified a split into six populations according to species and geography. The previously uncharacterized S. delavayi and S. rarak are diploid species, and here we propose hypotheses for their speciation. Selective sweeps suggested stress responses as well as alleles of the genes CYP716A, CAMTA and HD-ZIP involved in triterpenoid saponin biosynthesis to have been under selection in natural populations, while genome-wide association analysis revealed several homologues of fatty acid biosynthesis genes to be associated with kernel fatty acid quality. Our findings elucidate the genetic structure of Sapindus in China, provide target loci for selection and suggest cultivar materials for genetic improvement.

Cyclocarya paliurus, endemic to the subtropical regions of southern China, holds significant potential as a health product, with its leaf-derived secondary metabolites commanding considerable value. This study aimed to investigate the secondary metabolites associated with graft success in C. paliurus by selecting three clones and three provenances as grafting scions and rootstocks. The survival rates of various graft combinations were meticulously recorded. Targeted metabolic profiling of the graft union was employed to analyze the flavonoid and phenylpropanoid biosynthesis pathways in both compatible and incompatible graft combinations. The results indicate that phenylpropanoids preferentially accumulate in compatible graft unions, while flavonoids are more abundant in incompatible unions. In the grafted seedlings of C. paliurus, ferulic acid, glycitein, dihydromyricetin, pinocembrin, and apigenin exhibited distinct accumulation patterns. These findings revealed the regulatory patterns within the phenylpropanoid biosynthesis pathway for predicting graft success in C. paliurus. The insights are valuable for the optimization of C. paliurus grafting practices and for future breeding programs aimed at enhancing the species’ horticultural and economic potential.

To reveal the effects of genotype–herbivore interactions on leaf quality, foliar variations in phytochemicals, morphoanatomy, and herbivory damage ratio were investigated in a Cyclocarya paliurus (Batalin) Iljinsk. (Juglandaceae) germplasm resources bank. Results showed less herbivory damage in genotypes with a higher leaf thickness, but more herbivory damage in genotypes with a higher leaf stomatal density. Herbivory damage ratios were significantly correlated with the contents of leaf secondary metabolites, whereas the response of secondary metabolites to insect attack was type-specific and varied between intact leaves and damaged leaves. Based on key indicators of leaf quality (contents of triterpenoids, flavonoids, polyphenols, pterocaryoside A, pterocaryoside B, and cyclocaric acid B), the investigated genotypes were divided into three distinct groups by integrating TOPSIS and cluster analysis, while four genotypes with slight insect damage demonstrated the prioritization for future applications. Our findings lay a foundation for further selection of its superior varieties with both insect resistance and high leaf quality.

The leaves of Cyclocarya paliurus (Batalin) Iljinskaja, an endemic tree with a scattered distribution in subtropical China, are rich in flavonoids with beneficial, health-promoting properties. To understand the impact of environment and genetic similarity on the variation pattern of flavonoids in this species, we analyzed C. paliurus germplasm resources from 26 different populations previously sampled from the main distribution area. Environmental, genetic and biochemical data was associated by genetic structure analysis, non-parametric tests, correlation analysis and principal component analysis. We found that populations with higher flavonoid contents were distributed at higher elevations and latitudes and fell into two groups with similar genetic diversities. Significant accumulations of isoquercitrin and kaempferol 3-O-glucoside were detected in the higher flavonoid-content resources. In addition, the genetic clusters with higher flavonoid contents exhibited broader environmental-adaptive capacities. Even in the presence of environmental factors promoting C. paliurus flavonoid accumulation, only those populations having a specific level of genetic similarity were able to exploit such environments.

Cyclocarya paliurus is a relict plant species that survived the last glacial period and shows a population expansion recently. Its leaves have been traditionally used to treat obesity and diabetes with the well-known active ingredient cyclocaric acid B. Here, we presented three C. paliurus genomes from two diploids with different flower morphs and one haplotype-resolved tetraploid assembly. Comparative genomic analysis revealed two rounds of recent whole-genome duplication events and identified 691 genes with dosage effects that likely contribute to adaptive evolution through enhanced photosynthesis and increased accumulation of triterpenoids. Resequencing analysis of 45 C. paliurus individuals uncovered two bottlenecks, consistent with the known events of environmental changes, and many selectively swept genes involved in critical biological functions, including plant defense and secondary metabolite biosynthesis. We also proposed the biosynthesis pathway of cyclocaric acid B based on multi-omics data and identified key genes, in particular gibberellin-related genes, associated with the heterodichogamy in C. paliurus species. Our study sheds light on evolutionary history of C. paliurus and provides genomic resources to study the medicinal herbs.

[目的]研究青钱柳(Cyclocarya paliurus)种子雨的季节动态及土壤种子库特征,以阐明其种群更新和演替规律.[方法]以江苏溧阳大石山3种林分密度(1050、720和525株/hm2,代号依次为C1、C2、C3)青钱柳人工林为对象,对其种子雨季节动态及种子性状进行观测和分析;在江西九岭山5个青钱柳天然群落设样方调查,并对样方内的土壤种子库分枯枝落叶层(Ⅰ层)和土壤层(Ⅱ层)进行种子筛选和分析.[结果]根据青钱柳种子雨密度,将落种时期分为3个阶段:落种前期(8月20日—9月20日)、落种中期(9月21日—12月10日)和落种后期(12月11日—12月30日);种子雨出现2个高峰(9月10日和12月20日),落种前期和落种后期其单位面积落种量分别占全年的42.4％和43.5％;不同落种阶段的种子雨密度和具生活力的种子数差异显著,但其他种子性状差异不显著.林分密度显著影响青钱柳饱满种子数和种子千粒质量,但未影响其他种子性状.青钱柳天然群落的土壤种子库密度均呈现为Ⅰ层(37.4粒/m2)>Ⅱ层(17.9粒/m2),群落间的种子库密度差异达显著水平;Ⅱ层种子直径、厚度及体积均小于Ⅰ层种子.青钱柳群落土壤种子库的种子饱满度和生活力均较低,分别为13.0％～27.1％和0～10.4％;相比较而言,Ⅰ层种子生活力和饱满度总体上大于Ⅱ层,说明种子库中的种子寿命随着时间的延长呈下降趋势.[结论]青钱柳林分种子雨呈双峰特征,林分密度显著影响了种子雨密度和千粒质量,但对种子饱满度和生活力的影响不大;土壤种子库枯枝落叶层(Ⅰ层)种子数量和质量均优于土壤层(Ⅱ层)种子,贮存在土壤种子库的种子休眠被解除,有利于青钱柳群落的更新和演替.

Cyclocarya paliurus leaves contain abundant flavonoids with beneficial bioactivities and antioxidant activities. Red leaves of Cyclocarya paliurus have been considered to have higher flavonoids content, while the flavonoid derivatives accumulation pattern was still unclear. To uncover the flavonoids variation mechanism during red young leaf growing, transcriptome and metabolome analysis on Cyclocarya paliurus clone with red leaves was made. Leaves samples of young red leaf, half red leaf and old green leaf stage were researched. The result showed that young red leaf contained higher anthocyanin and quercetin contents, while lower kaempferol and catechins contents compared to old green leaf. And flavonoid biosynthesis-related unigenes (UDP-flavonoid glucosyl transferase) were identified for promoting anthocyanin accumulation in the flavonoid biosynthesis pathway. Besides, transcription factors were also found to influence the flavonoids variation pattern in the red leave of C. paliurus . These findings provide information about the relationship between flavonoids and leaf color, and will be useful for C. paliurus selection.

Secondary metabolites in Cyclocarya paliurus (Batalin) Iljinsk. leaves are beneficial for human health. The synthesis and accumulation of secondary metabolites form a complex process that is influenced by the trade-off between primary and secondary metabolism and by the biosynthetic pathways themselves. In this study, we explored the relationship between secondary metabolite accumulation and the activity of metabolic networks in leaves of C. paliurus. Leaves at three different growth stages were subjected to transcriptomic and non-targeted metabolomic analyses. The results revealed that nitrogen assimilation increased and carbon assimilation decreased as leaves matured, and the patterns of secondary metabolite accumulation and gene expression differed among the leaves at different growth stages. Mature green leaves had higher nitrogen assimilation and lower carbon assimilation, which were correlated with variations in secondary metabolite accumulation. As a major source of carbon and nitrogen, glutamine accumulated in the mature green leaves of C. paliurus. The accumulation of glutamine inhibited phenylalanine biosynthesis by modulating the pentose phosphate pathway but promoted acetyl-CoA biosynthesis through the tricarboxylic acid cycle. These changes led to decreased flavonoid contents and increased triterpenoid contents in mature leaves. These metabolomic and transcriptomic data reveal the differential expression of metabolic regulatory networks during three stages of leaf development and highlight the trade-off between primary and secondary metabolism. Our results provide a comprehensive picture of the metabolic pathways that are active in the leaves of C. paliurus at different growth stages.

The phenotypes of Sapindus are significantly influenced by environmental factors, but the responses of oil-related seed phenotypes to environmental factors are still unclear. We sampled 115 seed accessions of Sapindus mukorossi Gaertn. and 33 of Sapindus delavayi (Franch.) Radlk. from fifty-six distinct locations in China to explore the effects of environmental factors on the seed phenotypes. Pearson’s correlation analysis showed that 100-seed kernel weight (SKW), 100-seed shell weight (SSW), and seed kernel content (SKC) were the phenotypes most sensitive to the environmental influence (significantly associated with at least ten environmental factors). Redundancy analysis explained 26.13% of the variance and revealed that longitude was negatively correlated with SKW and SKC but was positively correlated with SSW, whereas elevation had the opposite effect. Monthly sunshine hours was negatively correlated with 100-seed weight and SSW. Additionally, the Mantel test showed that the seed phenotypic variations in Sapindus mukorossi and Sapindus delavayi were significantly affected by environmental factors differently. SKW and SKC of Sapindus delavayi were more sensitive to the influence of key environmental factors and therefore had more potential for oil development. It is recommended to cultivate Sapindus delavayi at lower longitudes to facilitate seed kernel development and promote oil yield. Study Implications: This study revealed the response pattern of the seed phenotypes of Sapindus mukorossi Gaertn. and Sapindus delavay (Franch.) Radlk. to environmental factors. Sapindus delavay had larger seed kernels and thinner seed shells, indicating a higher potential for oil production. At lower longitudes, the seed kernels of Sapindus are heavier, favoring kernel oil production, and the seed shells are lighter, which facilitates processing. This implied that growers can cultivate Sapindus in suitable climatic regions for commercial purposes such as oil production.

Sapindus L. species are widely cultivated for biodiesel, biomedical, and biochemical raw materials in southern China. However, yields fluctuate widely due to the lack of high-yielding, high-quality, stable cultivars. Therefore, the objectives of this study were to evaluate three species and one variety among 149 nationwide Sapindus species and screen for elite accessions which would serve as Sapindus breeding materials. Accessions were evaluated on 19 agro-morphological traits by correlation analysis and principal component analysis. These displayed substantial diversity and a broad range of economic traits. In particular, accessions of Sapindus mukorossi and Sapindus rarak had more variation in economic traits than Sapindus delavayi and Sapindus rarak var. velutinus. Increased saponin accumulation may be achieved at the cost of seed oil production. Thirty elite accessions for oil and saponin production, and for comprehensive utilization were screened and accessions no. 80, 110, and 112 had significant potential to produce high yields. These elite accessions will facilitate the identification of genetic determinants of valuable traits and the effective utilization of trait variability in Sapindus breeding.

[目的]青钱柳是多功能树种,通过比较分析两种不同叶色青钱柳叶片色素、黄酮和单宁两类多酚含量及其光合特性的差异,为青钱柳良种选育提供理论依据.[方法]按照季节动态分别采集红叶青钱柳和绿叶青钱柳的新叶和成熟叶,测定其花色素苷、叶绿素、类胡萝卜素、单宁和黄酮含量,定期测定4种类型叶的净光合速率(Pn)和PSⅡ最大光化学效率(Fv/Fm),并采用单因素方差分析比较不同类型叶间的差异.[结果]红叶青钱柳的新叶花色素苷含量显著高于其他3种类型叶(P<0.05),但叶绿素和类胡萝卜素含量显著低于红叶青钱柳和绿叶青钱柳的成熟叶片(P<0.05);红叶青钱柳和绿叶青钱柳的成熟叶片中的黄酮和单宁含量在多数采样时间均无显著差异(P>0.05),但在秋季,红叶青钱柳成熟叶片的单宁含量显著高于绿叶青钱柳的成熟叶片(P<0.05);由于红叶青钱柳的新叶积累高花色素苷含量而使总叶绿素含量下降,但其Pn与绿叶青钱柳的新叶不存在显著差异(P>0.05),红叶青钱柳和绿叶青钱柳成熟叶片的Pn也不存在显著差异(P>0.05).[结论]较高浓度的花色素苷是红叶青钱柳新叶呈现红色的主要原因;红叶青钱柳和绿叶青钱柳叶中单宁与黄酮的含量存在一定差异,但总体上差异不显著;红叶青钱柳新叶阶段叶多酚类物质含量较高,但在成熟叶阶段与绿叶青钱柳无显著差异(P>0.05).因此,红叶这一表型性状可为青钱柳药用优良单株的筛选提供一定参考,红叶青钱柳在7—8月叶片仍保持较高花色素苷含量而呈现红色,比绿叶青钱柳具有更高的观赏价值.

Background: Sapindus is an important biodiesel, biomedical, and multifunctional economic forest species in Asia, however its germplasms have been persistently damaged or lost. It is imperative to conserve the diversity of Sapindus . This study aimed to reveal the potential habitat distribution patterns of Sapindus mukorossi , Sapindus delavayi , and Sapindus rarak in response to current environment and future climate change, and identify hotspots of habitat degradation/expansion to facilitate climate change-adaptive biological conservation. Methods: Using current environmental data and future climate projections (2021–2100), we simulated the present and potential future habitats of Sapindus mukorossi , Sapindus delavayi , and Sapindus rarak in east and southeast Asia using a maximum entropy (MaxEnt) model that was developed based on 2041 occurrence records. Results: The model showed that precipitation may play an important role in framing the potential habitats of Sapindus ; however, S. delavayi was more sensitive to minimum temperatures (-2 °C to 3 °C) and elevation (1200-2000 m), while S. rarak was more demanding in terms of solar radiation (annual mean Uvb of 4600 to 5000 J/m 2 /day). Under the current environment, S. mukorossi has the widest suitable habitat distribution (250.24 × 10 4 km 2 ), followed by that of S. rarak (173.49 × 10 4 km 2 ), and S. delavayi (78.85 × 10 4 km 2 ). Under future climate change scenarios, the habitat distribution of S. mukorossi will expand and contract, that of S. delavayi exhibited significant expansion. In contrast, future S. rarak habitat distribution exhibited significant contraction. Conclusions: There were significantly distinct ecological adaptations among Sapindus mukorossi , Sapindus delavayi , and Sapindus rarak in east and southeast Asia. The contraction areas should be subject to germplasm collection and ex situ conservation preferentially. The modelled unchanged areas should be used for potential future Sapindus mukorossi , Sapindus delavayi , and Sapindus rarak conservation and utilization.

[目的]青钱柳是我国特有的珍稀多用途树种,研究青钱柳幼树地上部分生物量生长规律,为发展叶用林提供依据.[方法]以6年生的青钱柳人工幼林为研究对象,对其生长特性及生物量的分配进行了研究,同时选取了 37株样木进行地上部分生物量及相关测树因子的分析评价,从19个生物量模型中进行筛选,构建了青钱柳人工林各生物量组分及地上部分生物量与相关测树因子的预估方程.[结果]青钱柳幼林地上部分生物量(W)与胸径(D)具有高度相关性,筛选的4个模型均以胸径作为自变量,则:①干生物量模型W=0.15 D2.1,R2=0.982;②枝生物量模型W=0.05D1.88,R2=0.864;③叶生物量模型W=0.07 D1.55,R2=0.802;④地上部分生物量模型W=0.28D1.95,R2=0.976.[结论]不同密度下6年生青钱柳幼林生长尚未郁闭,受密度效应的影响较低,胸径、树高和单株材积的总生长量之间差异不显著,单株和林分生物量分配模式基本相似,地上部分各器官生物量分配由大到小表现为干(73％)＞枝(16％)＞叶(11％).

[目的]在对3.5年生青钱柳种质资源进行评价的基础上,初选适合南京及周边环境相似地区的优良家系及单株,为青钱柳定向培育提供理论依据.[方法]以青钱柳种质资源库31个家系为材料,测定其生长性状和叶总黄酮、总三萜、总多酚含量,分析各性状间的差异,并对青钱柳家系进行聚类分析,同时利用熵权法进行优良家系-单株配合选择.[结果]青钱柳树高、地径等生长性状及叶总黄酮、总三萜、总多酚含量在参试家系间存在显著差异;聚类分析将31个参试家系聚为4类,第1类推荐为高三萜积累家系,第2类推荐为高多酚积累家系,第3类推荐为高黄酮积累家系,第4类为叶次生代谢物综合含量表现较差家系.根据生长性状和叶主要次生代谢物含量的数据,采用熵权法初选出7个优良家系,分别为GXJZS7#、GZSQ12#、GXLS26#、HNYS2#、AHQLF13#、SCMC31#和GXJZS1#;针对优良家系内单株进一步进行综合评价,筛选出11株优良单株,在叶片总黄酮、总三萜和总多酚含量上综合表现较优.[结论]青钱柳生长和次生代谢物含量在家系间存在显著差异,为青钱柳良种选育提供了极大的空间;基于优良家系-单株配合选择,初步筛选出7个优良家系和11株优良单株可用于进一步试验和应用.

Cyclocarya paliurus is mainly distributed in subtropical areas of China. Its leaves are rich in beneficial triterpenoids that have bioactivities against human diseases, including hyperlipemia, diabetes, and hypertension. In this study, data on the genetic diversity, distributing environment, and triterpenoids of C. paliurus samples were collected from a wide area in China. The data covered 316 C. paliurus germplasms collected from 26 distinct populations. Association analysis between genotype and triterpenoids was carried out to describe triterpenoids accumulation pattern. Based on our analyses, we identified the important trend that genotypes with higher triterpenoid contents belonged to a unique genotype subgroup. The results showed that pterocaryoside B and pterocaryoside A significantly vary among the genotypic subgroups. In addition, the different genotypic subgroups showed distinct geographical distributing areas. These findings provide information about the relationship between genetic and environmental factors and how this affects triterpenoids accumulation. This information will be valuable for targeted breeding and for further germplasm selection of C. paliurus resources.

[目的]基于我国无患子属空间分布数据,探索无患子属的适生区区划及主要生态特征,为无患子属种子调拨、种质资源多样性保护、引种栽培、合理选址提供科学依据.[方法]基于我国17省(区、市)无患子属226份种质资源空间分布数据,叠加分析后筛选133份代表性分布数据,结合24个生态因子,采用最大熵模型(MaxEnt)开展无患子属适生区区划并建立与生态因子的关系模型,运用受试者工作特征曲线(ROC曲线)检测模型精度,刀切法(Jackknife)筛选主导生态因子;结合ArcGIS系统实现我国无患子属适生区可视化.[结果]MaxEnt模型模拟结果可信度高,无患子属适生区区划结果ROC曲线训练集和测试集AUC值均达到0.990以上;无患子属适生区面积为248.71万km2,占国土面积的25.81％,其中无患子为240.66万km2(占国土面积的24.99％)、川滇无患子为78.99万km2(占国土面积的8.20％)、毛瓣无患子为100.40万km2(占国土面积的10.42％);显著影响无患子适生区区划的生态因子为最暖季降水量(贡献率为57.1％)和等温性(贡献率为22.6％),川滇无患子为最暖季降水量(贡献率为37.9％)、最冷季平均气温(贡献率为15.9％)、海拔(贡献率为12.8％)和降水量变异系数(贡献率为11.2％),毛瓣无患子为年均温度变化范围(贡献率为19.6％)、最暖季降水量(贡献率为17.8％)、根系的氧气有效性(贡献率为11.9％)和等温性(贡献率为11.1％).[结论]我国无患子属生态适生区广泛分布于华中和华南地区;无患子极适生区主要分布于我国福建省、广西壮族自治区、贵州省、重庆市、广东省北部、江西省南昌和赣州及四川盆地,川滇无患子极适生区集中于四川盆地、云南省昆明和曲靖,毛瓣无患子极适生区集中于云南省南部的玉溪、普洱、红河哈尼彝族自治州和文山壮族自治州;最暖季降水量是决定无患子属及各种适生区区划的最显著生态因子;无患子适宜在最暖季降水量400～800 mm、等温性为24％～35％的区域分布,川滇无患子适宜在海拔1200～3000 m、最冷季平均气温4～11℃的区域生存,毛瓣无患子更适合在年均温度变化范围较小(14～24℃),最暖季降水量较高(550～1550 mm)的热带地区分布.

Sapindus ( Sapindus L.) is a widely distributed economically important tree genus that provides biodiesel, biomedical and biochemical products. However, with climate change, deforestation, and economic development, the diversity of Sapindus germplasms may face the risk of destruction. Therefore, utilising historical environmental data and future climate projections from the BCC-CSM2-MR global climate database, we simulated the current and future global distributions of suitable habitats for Sapindus using a Maximum Entropy (MaxEnt) model. The estimated ecological thresholds for critical environmental factors were: a minimum temperature of 0–20 °C in the coldest month, soil moisture levels of 40–140 mm, a mean temperature of 2–25 °C in the driest quarter, a mean temperature of 19–28 °C in the wettest quarter, and a soil pH of 5.6–7.6. The total suitable habitat area was 6059.97 × 10 4 km 2 , which was unevenly distributed across six continents. As greenhouse gas emissions increased over time, the area of suitable habitats contracted in lower latitudes and expanded in higher latitudes. Consequently, surveys and conservation should be prioritised in southern hemisphere areas which are in danger of becoming unsuitable. In contrast, other areas in northern and central America, China, and India can be used for conservation and large-scale cultivation in the future.

Cyclocaryapaliurus leaves are rich in triterpenoids with positive results in the treatment of diabetes, antioxidation, and scavenging free radicals. C. paliurus red leaves have been found to contain higher flavonoids including anthocyanin, however, the triterpenoids accumulation pattern is still unclear. For the purpose of researching the triterpenoid accumulating mechanism during red new leaf development, transcriptome and metabolome analysis was conducted during C. paliurus the red leaf development process. The results uncovered that most triterpenoid ingredients were found to accumulate during leaves turning green, while the unique ingredients content including cyclocaric acid A, cyclocarioside I, cyclocarioside Ⅱand cyclocarioside Ⅲ decreased or remained unchanged. Functional structure genes (hydroxymethylglutaryl-CoA synthase, hydroxymethylglutaryl-CoA reductase, and farnesyl-diphosphate synthase) were identified for promoting triterpenoids accumulation mainly in the mevalonic acid pathway (MVA). Moreover, glycosyltransferase (UGT73C, UGT85A, and UGT85K) was also found attributed to triterpenoids accumulation. These findings provide information for a better understanding of the triterpenoid biosynthesis mechanism during leaf development and will be useful for targeted breeding.

Sapindus (Sapindus L.) is a widely distributed economically important tree genus that provides biodiesel, biomedical and biochemical products. However, with climate change, deforestation, and economic development, Sapindus germplasm resources have been lost. Therefore, utilising historical environmental data and future climate projections from the BCC-CSM2-MR global climate database, we simulated the present and future global distributions of suitable habitats for Sapindus using a Maximum Entropy (MaxEnt) model. The estimated ecological thresholds for critical environmental factors were: a minimum temperature of 0–20°C in the coldest month, soil moisture levels of 40–140 mm, a mean temperature of 2–25°C in the driest quarter, a mean temperature of 19–28°C in the wettest quarter, and a soil pH of 5.6–7.6. The total suitable habitat area was 6059.97 × 104 km2, which was unevenly distributed across six continents. As greenhouse gas emissions increased over time, the area of suitable habitats contracted in lower latitudes and expanded in higher latitudes. Consequently, surveys and conservation should be prioritised in southern hemisphere areas which are in danger of becoming unsuitable. In contrast, other areas in northern and central America, China, and India can be used for conservation and large-scale cultivation in the future.