Collection, characterization and utilization of genetic resources are crucial for developing varieties to meet current and future needs. Although mango is an economically important fruit tree, its genetic resources are still undocumented and are threatened in their natural habits. In this study, the variability of 452 mango accessions from three regions in China (Nujiang, Lancang river and Honghe) was assessed using 41 descriptors including qualitative and quantitative traits, with the aim to identify mango accessions with excellent agronomic and quality traits. To this end, descriptive and multivariate analyses were performed. Based on Shannon–Weaver diversity index, qualitative traits including pericarp color, fruit aroma, flesh color, and fruit flavor recorded the highest variability in the germplasm. Fruit related traits including pulp weight, peel weight, and fruit weight were the most diverse traits in the germplasm with a high coefficient of variation (CV > 40%). Significant differences (MANOVA test, p < 0.000) were observed among the three regions for most of the quantitative traits. Biologically significant and positive correlations were found among agronomically important traits such as fruit weight and pulp weight, fruit weight and edible rate. The hierarchical cluster analysis revealed tree clusters, indicating a low diversity in the germplasm. The majority of the descriptors contributed to the differentiation of the accessions. Accessions with good fruits quality (high fruit weight, pulp weight, and edible rate) were found in Cluster 2. Accessions in this cluster could be used for fruit quality improvement in mango breeding programs. Our study sheds light on the diversity of a large collection of natural mango population in China and provides relevant information for efficient conservation and harnessing of mango genetic resources.

Mango (Mangifera indica L.) is a widely cultivated fruit in tropical and subtropical areas at altitudes ranging from 100 to 1500 m above sea level (masl). However, little is known about the effects of altering altitudes on the morpho-physiological traits determining the commercial value of mango. Therefore, we systematically investigated a commercial mango cultivar at eight altitudes ranging from 680 to 1400 masl to check the environmental impact on morpho-physiological attributes and volatile compounds using analysis of variance, principal component analysis, clustering, and correlation. We observed an increase in fruit weight and size from 680 to 1000 masl elevation and a gradual decrease at higher altitudes above 1000 msl. In contrast, quality parameters, including total soluble solids and total sugar, decreased with the increase in altitude, while the total acid increased with the increase in altitude. Moreover, we characterized the dried fruit, pericarp, and sarcocarp for aromatic compounds and identified 110 volatile compounds. The accumulation pattern of the volatiles suggested a considerable influence of environmental factors associated with altering altitudes. However, there was no clear trend in the volatile accumulation at different altitudes. We further determined the ten most frequently occurring volatiles at different altitudes and tissues. For instance, Alpha-Guaiene was only identified at 1000–1215 masl altitudes in dried fruit, while Beta-Ocimene showed the highest accumulation at 900 masl in dried fruit and pericarp. Together, our study provides clues on the impact of the altitude on mango fruit yield and quality attributes, which will guide future agronomic practices.