The plant glutamate receptor-like gene (GLR) plays a vital role in development, signaling pathways, and in its response to environmental stress. However, the GLR gene family has not been comprehensively and systematically studied in sugarcane. In this work, 43 GLR genes, including 34 in Saccharum spontaneum and 9 in the Saccharum hybrid cultivar R570, were identified and characterized, which could be divided into three clades (clade I, II, and III). They had different evolutionary mechanisms, the former was mainly on the WGD/segmental duplication, while the latter mainly on the proximal duplication. Those sugarcane GLR proteins in the same clade had a similar gene structure and motif distribution. For example, 79% of the sugarcane GLR proteins contained all the motifs, which proved the evolutionary stability of the sugarcane GLR gene family. The diverse cis-acting regulatory elements indicated that the sugarcane GLRs may play a role in the growth and development, or under the phytohormonal, biotic, and abiotic stresses. In addition, GO and KEGG analyses predicted their transmembrane transport function. Based on the transcriptome data, the expression of the clade III genes was significantly higher than that of the clade I and clade II. Furthermore, qRT-PCR analysis demonstrated that the expression of the SsGLRs was induced by salicylic acid (SA) treatment, methyl jasmonic acid (MeJA) treatment, and abscisic acid (ABA) treatment, suggesting their involvement in the hormone synthesis and signaling pathway. Taken together, the present study should provide useful information on comparative genomics to improve our understanding of the GLR genes and facilitate further research on their functions.

Sugarcane (Saccharum spp.) is an important sugar and energy crop worldwide. As a core regulator of the salicylic acid (SA) signaling pathway, nonexpressor of pathogenesis-related genes 1 (NPR1) plays a significant role in the response of the plant to biotic and abiotic stresses. However, there is currently no report on the NPR1-like gene family in sugarcane. In this study, a total of 18 NPR1-like genes were identified in Saccharum spontaneum and classified into three clades (clade I, II, and III). The cis-elements predicted in the promotors revealed that the sugarcane NPR1-like genes may be involved in various phytohormones and stress responses. RNA sequencing and quantitative real-time PCR analysis demonstrated that NPR1-like genes were differentially expressed in sugarcane tissues and under Sporisorium scitamineum stress. In addition, a novel ShNPR1 gene from Saccharum spp. hybrid ROC22 was isolated by homologous cloning and validated to be a nuclear-localized clade II member. The ShNPR1 gene was constitutively expressed in all the sugarcane tissues, with the highest expression level in the leaf and the lowest in the bud. The expression level of ShNPR1 was decreased by the plant hormones salicylic acid (SA) and abscisic acid (ABA). Additionally, the transient expression showed that the ShNPR1 gene plays a positive role in Nicotiana benthamiana plants’ defense response to Ralstonia solanacearum and Fusarium solani var. coeruleum. This study provided comprehensive information for the NPR1-like family in sugarcane, which should be helpful for functional characterization of sugarcane NPR1-like genes in the future.

Mango is a globally vital tropical commercial fruit crop boasting a sizable industry and remarkable economic benefits. Nevertheless, mango leaves, abundant in carbohydrates, polyphenols and other nutrients, remain underdeveloped in comprehensive resource exploitation. First, comparative analysis of leaf phenotypic traits and nutritional quality at different developmental stages of the Guifei cultivar showed that mature leaves possessed significantly higher contents of soluble sugar, total polyphenols, and total flavonoids, as well as better comprehensive traits, indicating that the mature leaf stage is optimal for deep processing. Subsequent assays of 70 mango germplasms detected obvious differences in leaf phenotypic characteristics and nutritional quality among materials, with the coefficient of variation values ranging from 2.35% to 50.38%. Correlation analysis revealed significant intra-group correlations for leaf phenotypic indicators and antioxidant indicators, whereas the five basic nutritional indices were mutually independent. Cluster analysis classified the tested germplasms into four distinct groups with clear trait divergence and unique functional features. Five principal components were extracted from 11 leaf quantitative indices to construct a comprehensive evaluation system, which pinpointed elite accessions including Sri Lanka No.811, Nam Dok Mai, and Shuoshuai Mango, with Sri Lanka No.811 exhibiting the highest total polyphenol content. This study determines the optimal harvest period and elite germplasms for high-value utilization of mango leaves, facilitating special-purpose germplasm screening and targeted breeding.

Natural rubber from Hevea brasiliensis serves as an irreplaceable industrial raw material. Whether rubber-yield potential is constrained by sucrose-sink sucrose partitioning remains incompletely understood. Here, we integrated transcriptomics and targeted sugar metabolomics across leaves, bark and latex from three H. brasiliensis clones with contrasting yields (designated H, M, and L). Transcriptomic profiling revealed tissue-specific functional differentiation: leaves were enriched in photosynthetic carbon fixation, bark in substance transport, and latex in defence and regeneration. The H clone did not show enhanced transcriptional enrichment of photosynthetic pathways relative to the L clone. Instead, it displayed a higher transcript abundance of invertase and sucrose synthase genes alongside elevated hexose levels, pointing to putative genotypic differences in sucrose hydrolysis and hexose turnover. Metabolomic profiling revealed greater sucrose accumulation in leaves of the L clone, accompanied by relatively low sucrose concentrations in latex. WGCNA analysis identified the MEpink module as strongly correlated with leaf sucrose content. This module is enriched in thiamine and cyanoamino acid metabolism and contains candidate transcription factors WRKY40, MYC2 and NAC002. Our results suggest that yield variation among these clones correlates with distinct sucrose distribution and utilization profiles. These multi-omics signatures provide a molecular resource to support high-yield rubber tree breeding.