Search Results (152)

The improvement of sucrose yield in sugarcane is impeded by the crop’s complex polyploid genome and slow progress in breeding. To clarify how arginine (Arg) regulates sugar metabolism and identify key genes associated with sucrose transport and accumulation in sugarcane, a screening experiment was performed by spraying L-arginine hydrochloride on the leaves and leaf sheaths of three sugarcane varieties (YZ05-51, YZ08-1609, and YT93-159), which differ in growth vigor, leaf morphology and other phenotypic traits. YZ05-51 exhibited the most prominent sugar-increasing effect, and subsequent optimization experiments on its leaf sheaths revealed that 20 g/mu L-arginine hydrochloride at pH 7.0 was optimal, significantly enhancing stem sucrose content. Transcriptomic analysis revealed the upregulation of genes related to sucrose synthesis and transport, with candidate genes enriched in pathways such as starch-sucrose metabolism, glycolysis/gluconeogenesis, and ATP-binding cassette (ABC) transporters. Metabolomic analysis detected 32 sugar metabolites across three categories, of which 24 were differentially abundant (e.g., glucose, galactose, fructose, and mannose). Integrated multi-omics analysis identified key regulatory genes, including SBEs and TPS1 (sucrose synthesis and carbon flux regulation), RBSK, α-amylases, GH28 (starch breakdown, glycolysis, and sugar mobilization), ABC transporters, GTs, and TIM10/TIM12 (sucrose transporter). Collectively, these analyses demonstrate enhanced activity of genes and metabolites involved in sucrose synthesis/transport in leaf sheaths, accompanied by reduced synthesis of other monosaccharides and oligosaccharides. Vigorously metabolizing leaf sheaths is more conducive to sucrose transport. This study provides valuable insights into the molecular mechanisms underlying Arg-mediated sucrose accumulation specifically in the sugarcane YZ05-51 sugarcane, highlighting its critical regulatory roles. Full article

Sugarcane red rot is a critical constraint threatening the stability and sustainability of sugarcane production in Southwest China, where Yunnan and Guangxi Provinces are the core cultivation regions. To provide a scientific basis for targeted disease management and ensure sugarcane production security, 40 symptomatic red rot samples were collected from 10 sugarcane varieties across 7 locations in these two provinces. A total of 57 fungal isolates were obtained, and they were identified through morphological characterization, multigene phylogenetic analysis (ITS/ACT/TUB2 for Colletotrichum sp. and EF-1α/RPB2 for Fusarium sp.), and pathogenicity tests on the susceptible cultivar Yuetang 93-159 using three representative isolates per species. The results show that 36 isolates were identified as Colletotrichum falcatum and divided into light and dark morphotypes. Phylogenetic analysis revealed that Yunnan and Guangxi isolates clustered in Clade I and Clade II, respectively. The remaining 21 isolates were identified as Fusarium madaense, and no sequence polymorphisms were detected in either EF1α or RPB2 among these isolates, which clustered with the F. madaense strain isolated from sugarcane in Brazil. Pathogenicity tests on leaf midribs and stalks of this cultivar showed that the representative isolates of C. falcatum and F. madaense induced typical red rot symptoms consistent with field observations. Among the representative isolates tested, preliminary findings suggest that light-type C. falcatum isolates were more virulent than dark-type ones, and the C. falcatum isolates Cf16 and Cf1 showed higher stalk virulence than the tested F. madaense isolates. To our knowledge, this is the first report of F. madaense causing typical red rot symptoms on sugarcane in China. Full article

Sugarcane streak mosaic disease (SCSMD) can reduce sugarcane yields by up to 70%. Since the first confirmation of SCSMD in 2018 in Sucrerie d’Afrique de Côte d’Ivoire (SUCAF-CI) plantations in Ferkessédougou, the epidemiology of the disease has never been studied. Therefore, the aim of this work was to evaluate various SCSMD parameters within the SUCAF-CI sugarcane germplasm, which comprises sugarcane varieties from diverse geographic origins. To that end, an epidemiological and molecular assessment was conducted on 548 varieties of SUCAF-CI sugarcane germplasm, preserved at two sites (Ferké 1 and Ferké 2) to evaluate SCSMD incidence and severity, determine the diversity of SCSMV strains infecting sugarcane at SUCAF-CI, identify sugarcane varieties that are potentially resistant to sugarcane streak mosaic virus (SCSMV), and investigate the presence of alternative hosts in SUCAF-CI plantations. The results reveal a very high incidence of the disease three months after planting (91.27 ± 23.28% in Ferké 1; 90.73 ± 22.80% in Ferké 2), followed by a significant increase at eight months (97.32 ± 11.79% and 96.45 ± 15.55%, respectively). The mean severity of the disease was low at both sites, with an average of 1.31 ± 0.02 at Ferké 1 and 1.05 ± 0.02 at Ferké 2. The varieties M292/70 and M700/86, which proved to be potentially resistant in the germplasm, showed symptoms in the industrial plots. Molecular analyses confirmed the presence of SCSMV in the germplasm studied, with a high overall prevalence of 71.32%. The infection rate was lower at Ferké 1 (55.8%) than at Ferké 2 (85.8%). Phylogenetic analysis of the SCSMV sequences obtained in this study showed that they are closely related to sequences from Côte d’Ivoire, India, Iran and Pakistan. No alternative hosts for SCSMV were identified. These findings highlight the critical importance of rigorously monitoring the importation of plant material and establishing a global management strategy that prioritizes the production of certified pathogen-free sugarcane plants. Full article

Axillary bud germination in sugarcane is a critical agronomic trait that directly determines seedling emergence and tillering capacity; however, its molecular regulatory mechanisms remain poorly understood. In this study, we systematically investigated the hormonal dynamics and transcriptomic profiles of the sugarcane cultivar XTT22 across five developmental stages (from dormancy to the first new leaf stage). Our results revealed that abscisic acid (ABA) content fluctuated during germination, whereas indole-3-acetic acid (IAA) and gibberellin (GA) levels decreased significantly, suggesting their negative regulatory roles. In contrast, cytokinin (CTK) and ethylene (ETH) contents increased at the initiation stage, indicating positive promoting functions. Transcriptome analysis identified 31,513 differentially expressed genes (DEGs), which were significantly enriched in pathways related to hormone signal transduction, starch/sucrose metabolism, and photosynthesis. Weighted gene co-expression network analysis (WGCNA) constructed 12 co-expression modules, among which the antiquewhite4 module (negatively correlated with IAA, GA, and ABA contents) and the darkorange2 module (positively correlated with cytokinin content) were identified as key regulatory modules. From these modules, seven core hub transcription factors (e.g., ScTCP5, ScSCR, and ScSHR1) were screened, and their expression patterns were validated by RT-qPCR. Furthermore, the expression trends of six hormone-related DEGs were highly consistent with the RNA-seq data. Collectively, this study elucidates the hormonal dynamics and gene regulatory networks underlying axillary bud germination in sugarcane, providing candidate gene resources for breeding high-yield varieties with enhanced emergence and tillering capacity. Full article

This article analyzes the scale, fluctuations and geographical distribution of olive (Olea europaea) cultivation in Palestine over 550 years, from the Late Mamluk period (1300–1517), through the Ottoman era (1517–1917), until the end of the British Mandate in 1947. Although olive oil played a dominant role in the diet and the local economy, there is currently no research that measures and quantifies the number of olive trees or the number of villages and towns that cultivated olive trees and produced olive oil. We reconstruct the agricultural landscape with its vast olive groves and examine the cultural history of olive tree farming, the growth of the olive oil industries and their economic role and importance. The earliest figures we have, that are from the year 1596, show that 400 villages cultivated 1,400,794 olive trees. By 1943, there were 6,053,367 olive trees that were cultivated by 644 villages. We found a strong correlation (R² = 0.96, p < 0.01) between the number of olive trees and the number of villages, indicating that olive oil demand and the olive oil industry align with population size. The research data derives from a variety of medieval local chroniclers, as well as diaries by European, North African and Middle Eastern travelers who provide descriptions of olive groves and the olive oil industry. Among the most important sources are the 1596 Ottoman tax registers. The tax registers are the first document that present clear-cut figures on the numbers of olive trees, olive presses and the names of the villages that cultivated olive groves. The main sources for the last period dealt with in this study are the British Mandate maps (1943), which display the acreage of the different crops across Palestine. The data from the maps is supplemented by two modern works on olive cultivation written by agronomists Assaf Goor (b. 1894) and Ali Nasouh (b. 1906) who were born in Palestine and employed by the British department of agriculture. The analysis of data shows that demands of local and oversea markets; the olive oil soap industry, which was based on the local olive oil; as well as competing agricultural crops like sugarcane, cotton and citrus, contributed to a complex economic structure. Olive tree cultivation did not depend on government investment. Olive groves in Palestine were rain fed, and, except for the harvest, they required relatively few working days a year. Hence, moderate policies (low taxation during periods of drought and low yields) adopted by enterprising local rulers and the central British government created a unique and relatively balanced relationship between rulers and farmers, which encouraged olive cultivation and led to a constant increase in the number of olive trees and the development of the olive oil industry. Full article

Sugarcane (Saccharum spp.) is a globally vital sugar crop, yet its productivity faces severe challenges from infestation by Chilo sacchariphagus. To decipher the plant’s molecular and metabolic defense mechanisms, this study applied an integrated transcriptomic and metabolomic analysis to three field-grown sugarcane cultivars (Zhongtang 4, 5, and 6) under natural borer stress. The transcriptomic analysis identified a total of 34,004 differentially expressed genes (DEGs), of which 18,674 were up-regulated, and 15,330 were down-regulated. The three cultivars exhibited distinct transcriptional regulatory patterns: Z4 and Z5 showed a global suppression-type response and a strong activation-type response, respectively, and Z6 presented a balanced-type response. A functional enrichment analysis revealed that the DEGs were significantly involved in metabolic processes, stress response, plant hormone signal transduction, phenylpropanoid biosynthesis, and plant-pathogen interaction pathways. Metabolomic analysis detected 963 differentially accumulated metabolites (DAMs), primarily including flavonoids, phenolic acids, amino acids and their derivatives, and lipids. These metabolites were significantly enriched in pathways such as amino acid metabolism, biosynthesis of secondary metabolites, and glutathione metabolism. Integrated multi-omics analysis further revealed strong synergistic regulatory relationships between gene expression and metabolite accumulation, particularly in defense-related secondary metabolic pathways, such as phenylpropanoid and flavonoid biosynthesis. Several key regulatory hubs were identified, including novel transcripts and D-xylulose-5-phosphate. Sugarcane employs a genetic background-dependent, multi-layered transcriptional reprogramming and metabolic restructuring to cope with borer stress. Cultivars Z4 and Z6 tend to activate and accumulate defensive compounds, while Z5 exhibits a different pattern of metabolic resource allocation. This research provides a systematic elucidation of the molecular mechanisms underlying insect resistance in sugarcane and offers important candidate genes and metabolites for breeding resistant varieties. Full article

Sugarcane (Saccharum spp. L.) is a globally vital sugar and energy crop whose genetic improvement has been constrained by its complex polyploid–allopolyploid genome. To address this limitation, we developed a practical, high-throughput single-nucleotide polymorphism (SNP) genotyping system. Using specific-locus amplified fragment sequencing (SLAF-seq) on 107 diverse accessions, we identified 2,420,550 high-quality SNPs anchored to the Saccharum officinarum LA-Purple genome. Stringent filtering yielded 55,750 SNPs for population analysis, which revealed three distinct genetic groups consistent with breeding history and adaptation. From these resources, 329 SNPs were converted into PCR-based ligase detection reaction (PCR-LDR) markers, resulting in a validated panel of 177 highly reliable SNPs (151 core and 26 extended) organized into an efficient multiplex typing system. The panel exhibited exceptional discriminatory power, successfully distinguishing all 303 tested sugarcane varieties and clearly resolving 186 individuals from three segregated hybrid populations. Compared to existing SSR and SNaPshot platforms, this SNP system offers superior experimental reproducibility, enhanced varietal clustering, and broader genome coverage. This work provides a robust, efficient genotyping tool to advance sugarcane variety identification, germplasm management, pedigree analysis, and marker-assisted breeding, with potential applicability to other complex polyploid crops. Full article

Sugarcane production in China is severely constrained by frequent seasonal droughts, especially in the major planting region of Guangxi. Identifying drought-resistant varieties is crucial for ensuring yield stability. This study aimed to comprehensively evaluate the drought resistance of 15 sugarcane varieties and screen key identification indicators. A pot experiment was conducted with both well-watered (control) and drought-stress treatments. Fifteen agronomic and physiological traits were measured, and drought resistance was assessed using the comprehensive drought resistance evaluation value (D value), the comprehensive drought resistance coefficient (CDC), and the weighted drought resistance coefficient (WDC). Results showed significant variations in trait responses to drought: green leaf number (NGL) decreased the most (66.06%), while proline (Pro) increased the most (88.09%). PCA reduced 15 traits to 5 principal components, with a cumulative variance contribution rate of 82.26%. Comprehensive evaluation using D values, comprehensive drought resistance coefficients (CDCs), and weighted drought resistance coefficients (WDCs) showed consistent overall drought resistance rankings, with slight differences in individual varieties. Cluster analysis based on D values classified the 15 varieties into three groups: 10 drought-resistant (66.67%, e.g., YZ08-1609, LT5), 3 moderately drought-resistant (e.g., GT08-56), and 2 drought-sensitive (GT10-612, ZT13-012). Grey relational analysis identified single stalk weight (SSW), number of leaves (NL), and number of green leaves (NGL) as key indicators closely associated with drought resistance. This study provides a scientific basis for establishing a drought-resistant sugarcane variety evaluation system and lays the foundation for breeding drought-resistant varieties. Full article

Potassium (K) is the nutrient most required by sugarcane crops and is predominantly supplied through potassium chloride (KCl). However, as KCl production is highly concentrated in a few countries, Brazil—the world’s largest sugarcane producer—relies heavily on imported K fertilizers. In this context, identifying alternative sources, even if also imported, is strategic to diversify supply and reduce the risks associated with dependence on a single product. This study evaluated the performance of polyhalite, a natural multinutrient mineral, compared with KCl, as an alternative fertilizer for ratoon cane (CTC 4 variety) grown in a clay-textured Oxisol in Jataí, Brazil. A two-year field experiment was conducted evaluating four treatments: control (without K fertilization), KCl, polyhalite, and a 25/75 polyhalite + KCl blend. Potassium fertilization increased culm yield by about 38–61% compared with the unfertilized control. In addition, the association of polyhalite + KCl promoted greater plant height compared to the treatment without K fertilization and, when comparing the K sources applied alone, polyhalite promoted a larger culm diameter and a higher leaf S content than KCl. These results demonstrate the agronomic advantages of polyhalite and its blends for sugarcane fertilization, which reiterates their potential as efficient and sustainable alternatives to KCl and as part of a broader strategy for fertilizer-source diversification. Full article

Sugarcane yield plays a crucial role in food safety and biofuel production, and it is strongly influenced by climatic variations. In this context, this study applies canonical correlation analysis (CCA) to identify the climatic predictors, such as sea surface temperature, atmospheric pressure, and wind speed, that affect sugarcane yield from 1990 to 2019. Hierarchical cluster analysis applied to the performance of 58 municipalities in the eastern region of Pernambuco identified three distinct and homogeneous groups. An analysis of the CCA for the three sugarcane yield groups and climatic variables revealed that the first canonical function was significant with R = 0.82 and precision of 0.67 (p ≤ 0.05 at 95% confidence level), and that the sugarcane yield groups and climatic variables were different (Wilks’ lambda = 0.14), but they were associated. Climatic variables affected the three sugarcane productivity groups, with redundancy indices of 29.7%, 52.2%, and 59.9%. Climatic variables with positive canonical weights enhance performance, while those with negative weights decrease yields. The structural canonical loads and cross-loadings reveal that sea surface temperature plays a crucial role in determining sugarcane yield, potentially influencing precipitation and temperature patterns in the region. The sensitivity analysis confirms the stability of the canonical loads and the robustness of the results, demonstrating that this research can support yield forecasting, regional agricultural policy, and drought management. Identifying climate predictors, such as sea surface temperature, wind speed, and atmospheric pressure, enables the creation of accurate models to predict sugarcane productivity, assisting farmers in planning input management, irrigation during dry periods, and harvesting. Furthermore, climate data can inform policies that encourage sustainable agricultural practices and adaptation to climate conditions, strengthening food security and guiding the selection of more resilient sugarcane varieties, increasing production resilience. Full article

Lignocellulosic biomass may play a major role in the production of biofuels, bioplastics, sugar, paper, and various other industrial products. In addition, it is a key trait in plants due to its contribution to lodging resistance. Fiber also shows a significant negative correlation with most yield traits and all sugar traits. As the most harvested crop globally by tonnage, sugarcane is an important resource for both sugar and bioenergy production. In this study, a panel of sugarcane clones was utilized to investigate the fiber content. This panel included 17 core parental lines derived from 11 countries involved in sugarcane cultivation and breeding. It represented the genetic base of commercial sugarcane breeding programs in China and other countries. The objective of this research was to identify molecular markers and candidate genes associated with fiber content in sugarcane using genome-wide association studies (GWASs). By integrating 5,964,084 high-quality single-nucleotide polymorphisms (SNPs) with phenotypic data collected across five different environments, a total of 69 SNPs spanning 41 quantitative trait loci (QTLs) were identified. Based on functional annotations and genomic positions, these QTLs contained 52 candidate genes. These candidate genes encoded the ultraviolet-B receptor (UVR8), leucine-rich repeat receptor-like kinases (LRR-RLKs), serine/threonine kinases (STKs), cellulose synthase (CESA), vegetative cell wall protein glycoproteins1 (gp1), F-box protein, MYB transcription factor, and so on. These genes could directly or indirectly influence the fiber content in sugarcane. Furthermore, according to previous studies, among these candidate genes, five located in four QTL regions were proposed to be the most critical. They included Sspon.02G0041160-2C, encoding CESA; Sspon.03G0039010-1C and Sspon.03G0039030-1C, both encoding gp1; Sspon.06G0023090-1B, encoding an F-box protein; and Sspon.07G0019440-2C, encoding a MYB transcription factor. The genetic basis of the fiber content was explored using elite breeding lines and their derivatives from the Chinese sugarcane breeding program. These candidate genes represent promising targets for future functional studies and may contribute to the development of different types of sugarcane varieties with correspondingly suitable fiber content through marker-assisted selection. Full article

Cadmium (Cd) is a toxic metal that affects living organisms even at low concentrations, causing physiological alterations and biomass reduction in plants. Arbuscular mycorrhizal fungi (AMF) represent a biological strategy that increases tolerance to heavy metals, although their specific mechanisms in sugarcane remain poorly understood. To address this knowledge gap, an open-field experiment was conducted to evaluate the effects of AMF on Cd accumulation, oxidative stress, photosynthetic pigments, enzymatic antioxidant system, and non-enzymatic antioxidant compounds in sugarcane variety CC 01-1940, using a randomized block design. Results showed that AMF established symbiosis with plants, retaining Cd in the roots and reducing its translocation to leaves. Additionally, they decreased Cd-induced oxidative stress by reducing lipid peroxidation (MDA) and proline content. Although an initial decrease in photosynthetic capacity was observed, AMF helped maintain stable levels of photosynthetic pigments, preserving photosynthetic efficiency. They also activated antioxidant enzymes and increased antioxidant compounds such as reduced glutathione (GSH), non-protein thiols (NP-SH), ascorbic acid (AA), and phytochelatins (PC). These findings demonstrate that symbiosis with AMF protects sugarcane plants from cellular oxidative damage and reduces Cd concentrations in leaves. Therefore, the use of AMF represents an effective strategy to improve the antioxidant defense and resistance of sugarcane plants to cadmium stress. Full article

Sugarcane smut, caused by Sporisorium scitamineum, is a globally prevalent disease that severely impacts sugarcane yield and quality. The most cost-effective and sustainable approach to disease control is breeding for smut-resistant varieties. In this study, we conducted a genome-wide association study (GWAS) using a panel of core sugarcane parents and their derived lines to elucidate the genetic basis of smut resistance across seven different environments. We identified 68 new loci significantly associated with smut resistance across all the chromosomes. Based on functional annotations and genomic positions, 164 candidate genes were identified, many of which are related to enzymatic systems, resistance genes, transcription factors, and other pathways implicated in smut defense. Using resistance ratings and associated SNPs, we further selected ten elite parents and derivatives as potential donors for marker-assisted selection (MAS). This study provides a valuable reservoir of genetic resources for improving smut resistance in sugarcane. Full article

In this study, we aimed to evaluate physiological and agronomic traits in 120 sugarcane genotypes under early drought stress conditions in a field trial across various soil types. The experiment used a split-plot arrangement, with a randomized complete block design and two replications. Two different water regimes were assigned to the main plot: (1) non-water stress (CT) and (2) drought (DT) at the early growth stage, during which sugarcane was subjected to drought stress by withholding water for 4 months. The subplot consisted of 120 sugarcane genotypes. The stalk height, stalk diameter, number of stalks, photosynthetic traits including SPAD chlorophyll meter reading (SCMR) and maximum quantum efficiency of photosystem II photochemistry (Fv/Fm), and normalized difference vegetation index (NDVI) were measured at 3, 6, and 9 months after planting (MAP). Yield and yield component parameters were measured at 12 MAP. Drought treatments lead to significant changes in various physiological traits in the sugarcane. Clustering analysis classified 36 sugarcane varieties grown in sandy loam soil and 15 genotypes in loam soil into two main clusters. In sandy loam soils, Biotec4 and CO1287 exhibited outstanding performance in drought conditions, delivering high cane yields. Meanwhile, in loam soil, MPT13-118, MPT07-1, Q47, F174, MPT14-1-902, and UT1 exhibited the best drought tolerance. Under drought conditions, cluster 1 showed higher values for SCMR, NDVI, height growth rate (HGR), cane yield, and drought tolerance index compared to cluster 2. These findings suggest that breeders can utilize these genotypes to enhance drought resistance, and the identified physiological traits can assist in selecting stronger candidates for drought tolerance. Full article

Soybean (Glycine max (L.) Merrill) is globally valued for protein, oil, and biofuel applications. Thailand imports 99.8% of its soybean consumption due to declining cultivation areas. Northeastern Thailand presents substantial potential for expanding soybean production through integrated seed rotation systems in post-sugarcane (upland) and post-rice (lowland) environments. This study evaluated the newly developed ‘Morkhor 60’ soybean variety compared to three commercial varieties (SJ 5, 223*Lh-85, and CM 60) across thirteen diverse environments in Northeastern Thailand during 2022–2023. Field experiments employed a randomized complete block design with four replications per site. The ‘Morkhor 60’ demonstrated favorable yield stability and competitive performance across most environments. The variety showed broad adaptability across soil types (sandy loam to clay) and seasonal conditions (rainy and dry seasons) with minimal genotype-by-environment interactions. Chemical analysis revealed favorable protein content (39.63%) and oil content (14.66%). These findings support the cultivation of ‘Morkhor 60’ in integrated seed rotation systems, offering a viable strategy to reduce national soybean seed shortages while enhancing domestic production and agricultural sustainability. Full article