Search Results (32)

Cyperus esculentus, a drought-resistant Cyperaceae with ecological and economic value (stems/leaves as feed, tubers as oil source), stabilizes arid soils through its extensive root system. Understanding its biomass allocation strategies is crucial for comprehending carbon storage in arid environments. The results showed that allometric models best described leaf biomass, while Gompertz and logistic models provided superior accuracy (evaluated using R², p-value, AIC, RMSE, and RSS) for estimating root, tuber, and whole plant biomass. In our study, the equilibrium biomass showed that underground (74.29 g and 64.22 g) was superior to aboveground (63.63 g and 58.72 g); and the growth rate showed the same result, underground (0.112 and 0.055) surpassed aboveground (0.083 and 0.046). The initial inflection point (POI1 = 11) suggests that leaves are prioritized in acquiring limited resources to support growth. In conclusion, the tiller number is a reliable predictor for developing robust biomass models for C. esculentus. The Gompertz model is best for leaves, roots, and total biomass, while the logistic model is optimal for predicting tuber biomass in arid areas. The tiller number is a reliable predictor for developing robust biomass models for C. esculentus. The research findings have supplied useful insights into the growth modifications, production potential, and management experience gained from Cyperus esculentus plant agriculture. Full article

Weed and disease management in organic watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] production is challenging. Yellow nutsedge (Cyperus esculentus L.) and Palmer amaranth (Amaranthus palmeri S. Wats.) are two competitor weeds in watermelon plasticulture production systems. Anaerobic soil disinfestation (ASD) is an emerging non-chemical approach to control weeds and soilborne plant pathogens, especially in organic farming. The effect of ASD treatments on weeds and soilborne diseases is being documented on different specialty crops. However, the impact of ASD treatments on the crop and crop genotypes; specifically watermelon has not been elucidated. Therefore, the impact of chicken manure and molasses (CMM)-induced ASD on twenty commercially available watermelon genotypes/rootstocks and major weed species was evaluated in a high tunnel experiment. The experiment was constructed as a randomized complete block design with three replications. The treatments consisted of a factorial of carbon source (1) non-treated check (CK), (2) CMM by twenty watermelon genotypes and rootstock. Soil treated with carbon CMM demonstrated significantly greater cumulative anaerobicity (246,963) activity relative to CK (575,372). Under anaerobic conditions, CMM achieved 91% weed control compared to CK. A lower number of yellow nutsedge (2) and Palmer amaranth (1) counts were recorded in CMM compared to CK (8) and (28), respectively. Among watermelon genotypes, ‘Extazy’, ‘Powerhouse’, ‘Sangria’, and ‘Exclamation’ had greater vigor 8.5, 8.4, 8.4, and 8.3, respectively, at 28 days after transplanting in CMM-treated soil. Greater watermelon plant fresh biomass was recorded in CMM-treated soil for ‘Extazy’ (434 g), ‘Powerhouse’ (409 g), ‘Exclamation’ (364 g), and ‘Sangria’ (360 g). This study demonstrated the variable response of watermelon genotypes to CMM-induced ASD and provides a guide for germplasm selection in organic watermelon production under field conditions. Full article

LEA_5 domain-containing proteins constitute a small family of late embryogenesis-abundant proteins that are essential for seed desiccation tolerance and dormancy. However, their roles in non-seed storage organs such as underground tubers are largely unknown. This study presents the first genome-scale analysis of the LEA_5 family in tigernut (Cyperus esculentus L.), a Cyperaceae plant producing desiccation-tolerant tubers. Four LEA_5 genes identified from the tigernut genome are twice of two present in model plants Arabidopsis thaliana and Oryza sativa. A comparison of 86 members from 34 representative plant species revealed the monogenic origin and lineage-specific family evolution in Poales, which includes the Cyperaceae family. CeLEA5 genes belong to four out of five orthogroups identified in this study, i.e., LEA5a, LEA5b, LEA5c, and LEA5d. Whereas LEA5e is specific to eudicots, LEA5b and LEA5d appear to be Poales-specific and LEA5c is confined to families Cyperaceae and Juncaceae. Though no syntenic relationship was observed between CeLEA5 genes, comparative genomics analyses indicated that LEA5b and LEA5c are more likely to arise from LEA5a via whole-genome duplication. Additionally, local duplication, especially tandem duplication, also played a role in the family expansion in Juncus effuses, Joinvillea ascendens, and most Poaceae plants examined in this study. Structural variation (e.g., fragment insertion) and expression divergence of LEA_5 genes were also observed. Whereas LEA_5 genes in A. thaliana, O. sativa, and Zea mays were shown to be preferentially expressed in seeds/embryos, CeLEA5 genes have evolved to be predominantly expressed in tubers, exhibiting seed desiccation-like accumulation during tuber maturation. Moreover, CeLEA5 orthologs in C. rotundus showed weak expression in various stages of tuber development, which may explain the difference in tuber desiccation tolerance between these two close species. These findings highlight the lineage-specific evolution of the LEA_5 family, which facilitates further functional analysis and genetic improvement in tigernut and other species. Full article

Anaerobic soil disinfestation (ASD) is a promising alternative to synthetic chemical-driven pest management methods facilitated by incorporating carbon sources into the soil, tarping the soil with plastic mulch, and irrigating to soil saturation. To evaluate the impact of ASD on southern root-knot nematode [Meloidogyne incognita (Kofoid & White), SRKN] and yellow nutsedge (Cyperus esculentus L.) management in organically grown sweetpotato, greenhouse studies were conducted. The treatments were structured as a factorial of two carbon amendments [chicken manure + molasses (CM + M), and no additional carbon (control)] by 20 sweetpotato genotypes with 4 replications using a randomized complete block design. The results suggest that the microcosms receiving the carbon amendment spent the most time under anaerobic conditions (<200 mvh). Planting of sweetpotato genotypes in CM + M-treated microcosms resulted in 60–90% and 56–92% suppression of soil population and egg reproduction of SRKN as compared to no additional carbon. The application of CM + M reduced overall weed cover by 79% relative to the control. Sweetpotatoes in CM + M-treated microcosms had significantly higher dry above-ground biomass (6.8 g) as compared to the control (3.6 g). The results of this study demonstrated that ASD has the potential to manage nematodes and weeds in organic sweetpotato production systems. Full article

Plant oils rich in oleic acid (OA) are attracting considerable attention for their high nutritional value and significant industrial potential. Stearoyl-acyl carrier protein desaturases (SADs) are a class of soluble desaturases that play a key role in OA accumulation in plants. In this study, the first genome-wide characterization of the SAD gene family was conducted in tigernut (Cyperus esculentus L. var. sativus Baeck., Cyperaceae), an oil-rich tuber plant typical for its high OA content. Six SAD genes identified from the tigernut genome are comparative to seven reported in two model plants Arabidopsis thaliana and Oryza sativa, but relatively more than four were found in most Cyperaceae species examined in this study. A comparison of 161 SAD genes from 29 representative plant species reveals the monogenic origin and lineage-specific family evolution in Poales. C. esculentus SAD genes (CeSADs) were shown to constitute two evolutionary groups (i.e., FAB2 and AAD) and four out of 12 orthogroups identified in this study, i.e., FAB2a, FAB2b, FAB2c, and AAD1. Whereas FAB2a and AAD1 are widely distributed, FAB2b and FAB2c are specific to Cyperaceae, which may arise from FAB2a via tandem and dispersed duplications, respectively. Though FAB2d and AAD2 are also broadly present in monocots, they are more likely to be lost in the Cyperaceae ancestor sometime after the split with its close family, Juncaceae. In tigernut, FAB2a appears to have undergone species-specific expansion via tandem duplication. Frequent structural variation and apparent expression divergence were also observed. Though FAB2a and AAD1 usually feature two and one intron, respectively, gain of certain introns was observed in CeSAD genes, all of which have three introns. Despite recent expansion of the FAB2 group, CeFAB2-1 has evolved into the dominant member that was highly and constitutively expressed in all tested organs. Moreover, CeFAB2-1, CeAAD1, as well as CeFAB2-5 have evolved to be predominantly expressed in tubers and thus contribute to high OA accumulation. These findings highlight lineage-specific evolution of the SAD family and putative roles of CeSAD genes in tuber oil accumulation, which facilitate further functional analysis and genetic improvement in tigernut and other species. Full article

Interactions between plants and their endophytes alter their metabolic functions and ability to cope with abiotic stresses. In this study, high-throughput sequencing was used to analyze the species diversity and functions of endophytes in Cyperus esculentus var. sativus (CES) tubers under different heavy metal stress conditions. The results indicated that the number of observed endophytic species in the tubers increased under heavy metal stress (p < 0.05), leading to changes in species diversity and composition. The response of tuber endophytes to different metal concentrations varied, with certain endophytic bacteria and fungi, such as Pseudomonas, Novosphingobium, and Fusarium, showing increased abundance and becoming the dominant species in the tubers. Additionally, new endophytic genera, Actinophytocola and Monosporascus, emerged at specific metal concentrations (p < 0.05). Fatty acid salvage was enriched in the endophytes of CES, which may play an important role in assisting CES in responding to multiple heavy metal stresses. These findings showed that CES tuber endophytes undergo adaptive changes to support the ability of plants to cope with heavy metal stress. Full article

Saline–alkali (SA) stress is an abiotic stress that exists widely in the natural environment, seriously affecting the growth and development of crops. Tiger nut (Cyperus esculentus L.), a perennial herb of Cyperus in Cyperaceae, is considered a pioneer crop for growing and improving SA land due to its excellent adaptability and SA tolerance. This study is the first to evaluate the SA tolerance of tiger nut and the alleviative effects of nanomaterials (nano-selenium and multi-walled carbon nanotubes) and Arbuscular mycorrhizas (AMs) on SA stress. The results showed that the seedling fresh weight of tiger nut was the most suitable parameter to describe the dose–response effect of plant growth with increased SA concentration. Based on the log-logistic dose–response curve, the GR₅₀ values of NaCl and NaHCO₃ (the concentrations causing a 50% reduction in seedling fresh weight) were determined to be 163 mmol L⁻¹ and 63 mmol L⁻¹, respectively. Under these stresses, the exogenous application of MWCNTs at 100 mg L⁻¹ or Nano-Se at 10 mg L⁻¹ showed that the effect of SA on tiger nut was alleviated. Field evaluation further showed that the exogenous application of MWCNTs, Nano-Se, or AMs could effectively alleviate SA stress on tiger nut. Compared to the untreated control, the application of these substances significantly improved the plant photosynthesis-related parameter, antioxidant enzyme activity, plant height (height: 66.0–69.9 cm), tuber yield (yield: 23.4–27.4 g plant⁻¹), and oil quality of tiger nut under SA stress. The results of this study indicate that the application of MWCNTs, Nano-Se, or AMs, to tiger nut can alleviate SA stress and maintain seed yield, providing the possibility of using these nanoparticles to improve the SA tolerance of tiger nut in agricultural practice. Full article

LEA_1 domain-containing proteins constitute a class of late-embryogenesis-abundant proteins that are highly hydrophilic and predominantly accumulate in mature seeds. Though LEA_1 proteins have been proven to be essential for seed desiccation tolerance and longevity, little information is available on their roles in non-seed storage organs. In this study, a first genome-wide characterization of the LEA_1 gene family was conducted in tigernut (Cyperus esculentus L., Cyperaceae), whose underground tubers are desiccation tolerant with a moisture content of less than 6%. Five family members identified in tigernut are comparative to four to six found in seven other Cyperaceae plants, but relatively more than three reported in Arabidopsis. Further comparison of 125 members from 29 plant species supports early divergence of the LEA_1 family into two phylogenetic groups before angiosperm radiation, and gene expansion in tigernut was contributed by whole-genome duplications occurring after the split with the eudicot clade. These two phylogenetic groups could be further divided into six orthogroups in the momocot clade, five of which are present in tigernut and the remaining one is Poaceae specific. Frequent structural variation and expression divergence of paralogs were also observed. Significantly, in contrast to seed-preferential expression of LEA_1 genes in Arabidopsis, rice, and maize, transcriptional profiling and qRT-PCR analysis revealed that CeLEA1 genes have evolved to predominantly express in tubers, exhibiting a seed desiccation-like accumulation during tuber development. Moreover, CeLEA1 transcripts in tubers were shown to be considerably more than that of their orthologs in purple nutsedge, another Cyperaceae plant producing desiccation-sensitive tubers. These results imply species-specific activation and key roles of CeLEA1 genes in the acquisition of desiccation tolerance of tigernut tubers as observed in orthodox seeds. Our findings not only improve the understanding of lineage-specific evolution of the LEA_1 family, but also provide valuable information for further functional analysis and genetic improvement in tigernut. Full article

CLAVATA3 (CLV3)/EMBRYO SURROUNDING REGION (ESR)-related (CLE) genes encode a group of peptide hormones, which coordinate cell proliferation and differentiation in plants. Tiger nut (Cyperus esculentus L.) is a perennial monocot plant that produces oil-rich tubers. However, the mechanisms regulating tuber development in tiger nut are poorly understood, and nothing is known about CLE genes in tiger nut. In this study, we identified 34 CLE genes in the genomes, proteomes, and transcriptomes of C. esculentus (CeCLE). We analyzed their gene structures and expression profiles in different parts of the plant, at three stages of tuber development and in roots in response to dehydration stress. We found a relatively high expression level of CeCLE13 in growing tuber and suggested that the corresponding CLE peptide could be involved in the regulation of tuberization. We also analyzed CeCLE gene sequences in the genome of the most productive K-17 variety in the N. I. Vavilov All-Russian Institute of Plant Genetic Resources collection and found many single nucleotide polymorphisms, insertions, and deletions. Our data provides fundamental information for future research on tiger nut growth and tuberization. Full article

Cyperus esculentus seeds are often considered irrelevant for C. esculentus spread as their fragile seedlings would not establish or survive in agricultural soils. However, the ever-increasing spread and upsurge of genetically different clonal populations in NW-Europe raises questions about the establishment of C. esculentus seeds and the reproductive performance of seedlings. Indeed, little is known about the potential of C. esculentus seedlings to grow and propagate under outdoor conditions relative to plants grown from tubers. Seeds from different clonal populations were sown outdoors in various soil types and under different irrigation levels (rainfed, irrigated) to assess seed germination and seedling establishment. Additionally, two pot experiments were conducted with three different plant types (plants originating from mother tubers and from seeds harvested on open- or self-pollinated plants) obtained from eight clonal populations. Plant performance was investigated by measuring vegetative and generative parameters. Germination under outdoor conditions was significantly affected by clonal population and was highest in irrigated sand (5.3%). Germination in sand was 4.1 times higher in irrigated plots than in rainfed plots. In irrigated plots, germination was 3.8 and 4.7 times higher in sand than in sandy loam and clay, respectively. Depending on the year, three out of five to five out of six clonal populations produced more tubers when grown from mother tubers than from seeds. Maximal tuber reproduction factors of 1:965, 1:752, and 1:618 were achieved for plants from mother tubers and seeds from open- and self-pollinated flowers, respectively. Plants originating from open-pollinated seedlings have the potential to equal or exceed the vegetative reproductive capacity of plants originating from mother tubers. As a result of their ability to establish in situ and their substantial vegetative reproductive capacity, C. esculentus seedlings are highly relevant for agriculture and merit appropriate attention in any integrated weed management system targeting C. esculentus. Full article

Tiger nut is the tuber of the perennial herbaceous plant Cyperus esculentus L., whose unique underground tubers are not only the main reproductive organ but also an important oil storage site. Oleosin is the most abundant structural protein in the oil body, which is an important membrane structural protein, playing a role in the formation and stability of lipid droplets in oilseed crops. Most studies have focused on the oleosin in oilseeds, but rarely on the oil containing tuber. In this study, nine oleosin genes from the Cyperus esculentus transcriptome were identified and divided into two groups via phylogenetic analysis. The expression patterns of the nine oleosins were examined through quantitative real-time PCR (qRT-PCR) in various development stages of stem tissue (35 d, 50 d, 75 d, 90 d, and 120 d after sowing). The subcellular localization of CeOle4 indicated that this protein was localized exclusively to membrane, indicating that it functioned in the plasma membrane. The highly expressed gene CeOle4 within the CeOleosin gene family was further transformed into yeast cells and plant materials. The results demonstrate that CeOle4 can promote lipid synthesis, enhancing the stability of oil lipids at low temperature and changing seed phenotypic traits. This discovery addresses and enriches the research on the function of CeOleosin genes and lays the groundwork for future studies on novel and superior transgenic crops related to tiger nut. Full article

Intercropping is a vital cropping system that can create a conducive growth environment for crops and enhance land productivity. Tiger nuts (Cyperus esculentus L.) have high oil content and are adaptable to various soil types, making them a promising new oil crop with significant development potential. This study evaluated the plant height, leaf area, tiller numbers, biomass, land equivalent ratio (LER), and root morphological characteristics of tiger nuts. The agronomic traits and root distribution of tiger nuts and other crops were further investigated to achieve the goal of high yield for tiger nuts. Seven intercropping systems were implemented in the experiment: maize–tiger nut intercropping (MT), soybean–tiger nut intercropping (ST), cotton–tiger nut intercropping (CT), monoculture tiger nut (T), monoculture maize (M), monoculture soybean (S), and monoculture cotton (C). The results indicated that under different planting systems, the agronomic traits of tiger nuts in MT and ST modes were superior, with plant height and tiller numbers increasing by 7.6% to 11.6%. However, the plant height and Soil Plant Analysis Development (SPAD) values in CT mode were slightly lower than in T mode. Additionally, intercropping reduced the leaf area by 6.2% to 37.9%. Root development was more pronounced in intercropping modes, with the ST mode showing the most significant improvement, increasing the 0–20 cm root length density (RLD) by 12.2% to 45.7%. Therefore, each of the three intercropping modes demonstrated distinct advantages. The LER of the intercropping systems ranged from 1.10 to 1.24, enhancing land utilization, with tiger nuts being the dominant species. Compared to monoculture, the ST mode exhibited the best overall effect. Understanding the impact of different planting systems on tiger nuts provides valuable insights for developing tiger nut cultivation in Xinjiang. Full article

The tiger nut (Cyperus esculentus L.) is a usable tuber and edible oil plant. The size of the tubers is a key trait that determines the yield and the mechanical harvesting of tiger nut tubers. However, little is known about the anatomical and molecular mechanisms of tuber expansion in tiger nut plants. This study conducted anatomical and comprehensive transcriptomics analyses of tiger nut tubers at the following days after sowing: 40 d (S1); 50 d (S2); 60 d (S3); 70 d (S4); 90 d (S5); and 110 d (S6). The results showed that, at the initiation stage of a tiger nut tuber (S1), the primary thickening meristem (PTM) surrounded the periphery of the stele and was initially responsible for the proliferation of parenchyma cells of the cortex (before S1) and then the stele (S2–S3). The increase in cell size of the parenchyma cells occurred mainly from S1 to S3 in the cortex and from S3 to S4 in the stele. A total of 12,472 differentially expressed genes (DEGs) were expressed to a greater extent in the S1–S3 phase than in S4–S6 phase. DEGs related to tuber expansion were involved in cell wall modification, vesicle transport, cell membrane components, cell division, the regulation of plant hormone levels, signal transduction, and metabolism. DEGs involved in the biosynthesis and the signaling of indole-3-acetic acid (IAA) and jasmonic acid (JA) were expressed highly in S1–S3. The endogenous changes in IAA and JAs during tuber development showed that the highest concentrations were found at S1 and S1–S3, respectively. In addition, several DEGs were related to brassinosteroid (BR) signaling and the G-protein, MAPK, and ubiquitin–proteasome pathways, suggesting that these signaling pathways have roles in the tuber expansion of tiger nut. Finally, we come to the conclusion that the cortex development preceding stele development in tiger nut tubers. The auxin signaling pathway promotes the division of cortical cells, while the jasmonic acid pathway, brassinosteroid signaling, G-protein pathway, MAPK pathway, and ubiquitin protein pathway regulate cell division and the expansion of the tuber cortex and stele. This finding will facilitate searches for genes that influence tuber expansion and the regulatory networks in developing tubers. Full article

The cultivation of tiger nut (Cyperus esculentus L.) on marginal lands is a feasible and effective way to increase food production in Northern China. However, the specific influence of nitrogen fertilizer application on the growth dynamics, tuber expansion, overall yield, and nitrogen use efficiency (NUE) of tiger nuts cultivated on these sandy lands is yet to be fully elucidated. From 2021 to 2022, we conducted a study to determine the effect of N fertilizers on the leaf function morphology, canopy apparent photosynthesis (CAP), tuber yield, and NUE of tiger nut. The results indicate that the tuber yield and NUE are closely related to the specific leaf area (SLA), leaf area index (LAI), leaf nitrogen concentration per area (N_A), CAP, and tuber expansion characteristics. Notably, significant enhancements in the SLA, LAI, N_A, and CAP during the tuber expansion phase ranging from the 15th to the 45th day under the 300 kg N ha⁻¹ treatment were observed, subsequently leading to increases in both the tuber yield and NUE. Moreover, a maximum average tuber filling rate was obtained under the N300 treatment. These improvements led to substantial increases in the tuber yield (32.1–35.5%), nitrogen agronomic efficiency (NAE, 2.1–5.3%), nitrogen partial factor productivity (NPP, 4.8–8.1%), and nitrogen recovery efficiency (NRE, 3.4–5.7%). Consequently, 300 kg N ha⁻¹ of N fertilizers is the most effective dose for optimizing both the yield of tiger nut tubers and the NUE of tiger nut plants in marginal soils. Structural equation modeling reveals that N application affects the yield and NUE through its effects on leaf functional traits, the CAP, and the tuber filling characteristics. Modeling indicates that tuber expansion characteristics primarily impact the yield, while CAP predominantly governs the NUE. Above all, this study highlights the crucial role of N fertilizer in maximizing the tiger nut tuber yield potential on marginal lands, providing valuable insights into sustainable farming in dry areas. Full article

Yellow nutsedge (Cyperus esculentus L.) is cultivated worldwide due to its agricultural and biotechnological potential. In Brazil, it is considered a weed, and we lack studies on its cultivation. Overcoming tuber dormancy is crucial for propagation. This study aimed to assess various dormancy-breaking methods’ effects on tubers and initial plant development. The treatments included gibberellic acid immersion, ethylene exposure, purple nutsedge extract immersion, temperature conditioning, scarification, and bud cutting, along with a control. Scarification resulted in the shortest emergence time (0.904 days) and fastest emergence speed (5.092 tubers/day). Plant development was minimally affected by the treatments, with scarification and gibberellic acid (100 mg L⁻¹) resulting in taller plants (1.19–1.23 times higher than the control). The conditioning at 4 °C and 70 °C proved to be less effective in breaking dormancy. Purple nutsedge extract immersion and bud cutting hindered plant growth. Scarification emerged as the most effective dormancy-breaking method. This study provides insights into the cultivation of yellow nutsedge in Brazil, highlighting the effectiveness of scarification in improving tuber germination and the early growth stages of plants. Full article