Cactus Research Articles

Curvularia soli causes a new leaf spot disease on Pereskia aculeata

Pereskia aculeata (Barbados gooseberry) is a vegetable member of the Cactaceae family. Pereskia aculeata leaves are highly valued for culinary use in some Brazilian regions, mainly in Minas Gerais. In March 2023, severe leaf spot disease affecting P. aculeata plants was observed in Viçosa, Minas Gerais, Brazil. Notably, we found that Curvularia sp. was associated with disease symptoms. However, the fungus Curvularia has not been reported to cause any diseases in P. aculeata. Given the absence of any previous records documenting this fungus as a pathogen for this host, this study aimed to identify Curvularia species associated with leaf spots on P. aculeata and elucidate the etiology of the disease. The fungus was identified as Curvularia soli based on its morphological characteristics and molecular features using glyceraldeyde-3-phosphate dehydrogenase (GAPDH) and translation elongation factor 1-α (TEF1-α) for phylogenetic analyses. Healthy P. aculeata plants were inoculated with a representative isolate of C. soli and the same symptoms as observed in the field were reproduced. All steps were performed to fulfill Koch’s postulates and confirm the etiology of the disease.

Changes in the fruits and seeds morphometric, germination, phytochemicals content, and antioxidant capacity in seed ripening of Echinocereus stramineus

Within the cacti family, most studies have focused on the physicochemical characterization of the stems, fruits, and seeds from Mammillaria, Opuntia, Hylocereus, and Stenocereus genera. However, few information is focused on the morphological and physicochemical characterization of the stems, fruits, and seeds of other genera widely distributed in the arid and semiarid zones of the Chihuahuan desert, such as the genus Echinocereus. The objective of this study was to analyze the fruit morphology, morphometry, germination process, and phytochemical content in four stages of seed in fruit ripening from E. stramineus. Morphometric parameters were measured by picking ten fruits and sixty seeds for each ripening stage. The characterization of the germination process included the germination percentage, mean germination time, germination speed, and mean germination speed which were computed 21 days after germination. The quantification of total phenols, flavonoids, tannins, reducing sugars, protein, and antioxidant activity of seeds was determined using colorimetric approaches under basal conditions. The morphometric results revealed a negative correlation between the fruit ripening stage and total mass (r= -0.980, p = 0.020), shell mass (r= -0.986, p = 0.014), pulp mass (r = -0.979, p = 0.021), fruit length (r = -0.978, p = 0.022), fruit width (r = -0.968, p = 0.032) and fruit area (r = -0.960, p = 0.04). The germination characterization process showed a negative association between the fruit ripening stage and the seed germination percentage (r = -0.979, p = 0.021) and between the seed mean germination time and the mean germination speed (r= -0.986, p = 0.014). The content of flavonoids, reducing sugars, proteins, and antioxidant capacity showed significant differences among the four stages of fruit ripening; however, no association was found between seed phytochemical content and the ripening stage. This study provides the first data on seed phytochemicals and information on the germination process of E. stramineus seeds.

The plastomes of Lepismium cruciforme (Vell.) Miq and Schlumbergera truncata (Haw.) Moran reveal tribe-specific rearrangements and the first loss of the trnT-GGU gene in Cactaceae.

Recent studies have revealed atypical features in the plastomes of the family Cactaceae, the largest lineage of succulent species adapted to arid and semi-arid regions. Most plastomes sequenced to date are from short-globose and cylindrical cacti, while little is known about plastomes of epiphytic cacti. Published cactus plastomes reveal reduction and complete loss of IRs, loss of genes, pseudogenization, and even degeneration of tRNA structures. Aiming to contribute with new insights into the plastid evolution of Cactaceae, particularly within the tribe Rhipsalideae, we de novo assembled and analyzed the plastomes of Lepismium cruciforme and Schlumbergera truncata, two South American epiphytic cacti. Our data reveal many gene losses in both plastomes and the first loss of functionality of the trnT-GGU gene in Cactaceae. The trnT-GGU is a pseudogene in L. cruciforme plastome and appears to be degenerating in the tribe Rhipsalideae. Although the plastome structure is conserved among the species of the tribe Rhipsalideae, with tribe-specific rearrangements, we mapped around 200 simple sequence repeats and identified nine nucleotide polymorphism hotspots, useful to improve the phylogenetic resolutions of the Rhipsalideae. Furthermore, our analysis indicated high gene divergence and rapid evolution of RNA editing sites in plastid protein-coding genes in Cactaceae. Our findings show that some characteristics of the Rhipsalideae tribe are conserved, such as plastome structure with IRs containing only the ycf2 and two tRNA genes, structural degeneration of the trnT-GGU gene and ndh complex, and lastly, pseudogenization of rpl33 and rpl23 genes, both plastid translation-related genes.

Development of a diagnostic variable number tandem repeat marker and dual TaqMan genotyping assay to distinguish Lophophora species.

The Lophophora genus of the Cactaceae family includes Lophophora diffusa and Lophophora williamsii, which has traditionally been used as a natural analgesic; however, its use is now under strict regulation worldwide as it contains mescaline, a unique psychotropic agent. Recently, non-medical and illegal distribution and abuse of L. williamsii have increased worldwide; thus, effective species identification methods are urgently needed. Here, we identified a new variable number tandem repeat (VNTR) marker in the trnL intron region to identify and characterize species in forensic analyses. The VNTR marker has a unique structure of tandem repeats, each with 13 nucleotides; one repeat unit was found in L. williamsii and two in L. diffusa. Phylogenetic and length polymorphism analyses confirmed that this novel VNTR marker could distinguish between Lophophora species. Furthermore, our newly developed TaqMan genotyping assay utilizes two probes; the color and position of dots on the discrimination plot differ according to the tandem repeat count within the VNTR marker. The limits of detection of the assay were 0.000063ng (LW-VNTR probe-1) and 0.000066ng (LW-VNTR probe-2), indicating high sensitivity. Moreover, when crime scene samples of 16 presumed L. williamsii species were analyzed, the results coincided with those of gas chromatography-mass spectrometry, confirming the applicability of our marker for Lophophora species identification. Thus, the tandem repeats within the trnL intron region can be exploited as a VNTR marker to identify L. williamsii and L. diffusa. Our dual TaqMan genotyping assay based on a novel marker demonstrates potential for forensic applications.

Identifying the multiple drivers of cactus diversification

Our understanding of the complexity of forces at play in the rise of major angiosperm lineages remains incomplete. The diversity and heterogeneous distribution of most angiosperm lineages is so extraordinary that it confounds our ability to identify simple drivers of diversification. Using machine learning in combination with phylogenetic modelling, we show that five separate abiotic and biotic variables significantly contribute to the diversification of Cactaceae. We reconstruct a comprehensive phylogeny, build a dataset of 39 abiotic and biotic variables, and predict the variables of central importance, while accounting for potential interactions between those variables. We use state-dependent diversification models to confirm that five abiotic and biotic variables shape diversification in the cactus family. Of highest importance are diurnal air temperature range, soil sand content and plant size, with lesser importance identified in isothermality and geographic range size. Interestingly, each of the estimated optimal conditions for abiotic variables were intermediate, indicating that cactus diversification is promoted by moderate, not extreme, climates. Our results reveal the potential primary drivers of cactus diversification, and the need to account for the complexity underlying the evolution of angiosperm lineages.

A FTIR Evident-Based Exploration of the Antioxidant Activity of Five Threatened Cactus Species

Cacti, members of the botanical family Cactaceae, comprise approximately 127 genera and approximately 1,850 known species within the Caryophyllales order. Presently, various anthropogenic activities are causing the endangerment of several cactus species. Among the reasons cited for this threat, the aesthetic and medicinal values of cacti have garnered notable attention. This study aims to explore the medicinal potential, particularly in terms of antimicrobial, antioxidant, and phytochemical properties, of five threatened cactus species listed by the International Union for Conservation of Nature (IUCN) and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES): Micranthocereus estevesii, Euphorbia lactea, Haageocereus crestata, Ferocactus acanthodes and Mammillaria huitzilopochtli. A Fourier-transform infrared (FTIR) analysis was conducted to substantiate and corroborate the findings. Notably, no prior studies have investigated the medicinal properties of these five species, underscoring the novelty of our research. Initially, specimens of the five cacti were collected from the Regional Plant Resource Center, Bhubaneswar, air-dried, and milled into powder. Phytoconstituents were then extracted individually using polar (water) and non-polar (methanol) solvents. The antimicrobial properties were assessed using agar well diffusion assays against Candida albicans, Escherichia coli and Staphylococcus aureus. Results indicated that methanol extracts of Micranthocereus estevesii and Euphorbia lactea inhibited Candida albicans, while aqueous extracts of Micranthocereus estevesii and Ferocactus acanthodes inhibited Escherichia coli and Staphylococcus aureus. Methanol extracts exhibited superior antioxidant activity compared to aqueous extracts. FTIR spectroscopy revealed distinctive peak values representing various functional groups in the extract components, including alcohols, carboxylic acids, phenols, aldehydes, alkanes, alkenes, ketones, aromatics, aliphatic amines, primary amines, ethers, alkyl halides, and esters. Both aqueous and methanolic extracts demonstrated promising antibacterial efficacy among the five cactus species studied, suggesting their potential application in pharmaceuticals and medication development. However, habitat degradation and illegal commerce pose significant threats to these species, emphasizing the urgent need for conservation efforts.

The Cactaceae family in inselbergs of the Land of Sugarloaf Mountains, Southeastern Brazil

The Cactaceae family in inselbergs of the Land of Sugarloaf Mountains, Southeastern Brazil

PHYSICOCHEMICAL PROPERTIES OF MOROCCAN OPUNTIA DILLENII FRUIT, EXTRACTION OF BETACYANINS AND STUDY OF ITS STABILITY AND ANTIOXIDANT ACTIVITY

The Opuntia dillenii (O. dillenii) belongs to the Cactaceae family and usually grows in arid and semi-arid zones worldwide. This succulent plant is known for its multiple health benefits and virtues. In practical terms, the current study aims to investigate the morphological and the physicochemical characteristics of Opuntia dillenii fruit collected from Morocco, as well as the determination of flavonoids, polyphenols and betacyanins contents in order to characterize, identify and facilitate the valorization of this species. The obtained results are compared with existing literature and thoroughly discussed. In addition, the pigment of betacyanins was extracted from the fruit pulp and characterized by UV-visible spectrophotometry. The study of the stablity of betacyanins was carried out in the presence of certain parameters such as the change of pH, temperature, light and the addition of salt. The antioxidant activity of the extracted betacyanins was further examined using the DPPH free radical scavenging assay and the total antioxidant capacity method.

Chemical Composition, Nutritional Value, Antioxidative, and In Vivo Anti-inflammatory Activities of Opuntia Stricta Cladode.

The cactus family plant has been used in folk medicine for a long time. In this work, Opuntia stricta chemical composition and its antioxidative and anti-inflammatory properties were investigated. Our results showed that O. stricta is highly rich in fibers and minerals. The present study assessed the levels of polyphenol contents and antioxidant and in vivo anti-inflammatory activities. The highest phenolic compounds and antioxidant activity were observed in the methanolic extract. Concerning the qualitative analysis, nine phenolic and organic acids were identified and quantified by high-performance liquid chromatography (HPLC). Luteolin-7-Glu (4.25 μg/g), apigenin-7-Glu (3.15 μg/g), and catechin (2.85 μg/g) were identified as major phenolic compounds. The predominant fatty acids detected by gas chromatography (GC) coupled to a flame ionization detector were linoleic and linolenic acids (35.11%). A factorial design plan was used to determine the effect of temperature, agitation speed, and maceration period on phenolic contents. In vivo, the methanol extract from Opuntia stricta showed anti-inflammatory activity. The computational modeling reveals that O. stricta compounds bind VEGF, IL-6, and TNF-α with high binding scores that reach -8.7 kcal/mol and establish significant molecular interactions with some key residues that satisfactorily explain both in vitro and in vivo findings. These data indicate that Opuntia stricta cladode powder could be potentially useful in pharmaceutical and food applications.

Vivipary and light quality effects on seed germination of the columnar cactus, Cereus jamacaru

AbstractVivipary is a remarkable trait in the Cactaceae family. Here, we reported a case of vivipary in Cereus jamacaru and observed which season had the highest vivipary incidence by examining the types of fruits and seeds produced during two contrasting periods in a seasonally dry tropical forest in northeastern Brazil. Additionally, because seeds of this species are positively photoblastic, a germination experiment was conducted to confirm whether seeds inside viviparous fruits (VFs) exhibited changes in light sensitivity. Seeds from VFs were then subjected to different light quality treatments, and their germination was compared with that observed in seeds from non‐viviparous fruits (NVFs). Vivipary only occurred in fruits produced at the end of the rainy season. Viviparous fruits’ seeds had a higher germination percentage under far‐red light than NVFs’ seeds, suggesting that vivipary may favor seed germination under canopy‐shade light and therefore provide new avenues for survival in semiarid environments.

Cladodes of Opuntia ficus-indica (L.) Mill. Possess Important Beneficial Properties Dependent on Their Different Stages of Maturity.

Opuntia ficus-indica (L.) Mill. belongs to the Cactaceae family and the genus Opuntia; it is a succulent plant that adapts to extreme climatic conditions. The aerial part of the plant consists of the cladodes, morphological changes of branches that appear green, are covered with thorns, and are essential to reduce excessive perspiration of water. The composition of cladodes is very varied, and the main constituents are water, fibers, polysaccharides, proteins, fatty acids, vitamins, sterols, minerals, and polyphenols. Polyphenols are responsible for many beneficial activities for human health, such as antioxidant, anti-inflammatory, anticancer, and nutritional properties. The purpose of this manuscript was to compare the properties of cladodes belonging to the same plant but with different stages of maturity. Relative extracts were tested both in vitro and on a cell line and antioxidant and anti-apoptotic properties were found. The antioxidant activity was tested by the Oxygen Radical Absorbance Capacity (ORAC) test, the 1,1-diphenyl-2-picrylhydrazil (DPPH) test, and the measurement of cellular accumulation of reactive oxygen species (ROS). Anti-apoptotic activity was evaluated by the annexin/PI assay and measurement of caspases 9 and 3 expression. The results obtained showed that the extracts considered possess antioxidant and anti-apoptotic properties. However, the different stages of maturity of cladodes are essential for the performance of both functions. In addition, important variations were made in the dissolution of the extracts that brought greater safety in their use. In conclusion, this manuscript provides further information on cladodes of Opuntia ficus-indica, which can be used as adjuvants in many human pathologies.

Cactaceaes of the Brazilian Semiarid: Source of Bioactive Compounds

The semiarid region of Brazil stands out as one of the spaces with the highest diversity of plant species in the world, and the Cactaceae family the one that best represents the Brazilian semiarid. However, although there are many species of cacti in Brazil, their chemical potential has yet to be discovered. Given this, the present review aims to record the bioactive metabolites of native cactaceaes or not in Brazil, encompassing a description of its habitat and traditional uses. Compilations of ethnobotanical studies point to the importance of cacti species in the daily life of local cultures. Cactaceaes are used for food, economic, ornamental, and mystical purposes, among others, and stand out for their importance in traditional medicine, used to treat various diseases. Bioactive compounds in this family belong mainly to alkaloid groups, such as betalain, phenolic acids, terpenes and fatty acids. This review displays the relevance of the Cactaceae family in the face of the remarkable production of bioactive compounds.

Pythium aphanidermatum causing seedling damping-off of Hylocereus megalanthus in China.

Hylocereus megalanthus (family Cactaceae), commonly known as bird's nest fruit (Yanwo fruit), was a new tropical plant cultivated commercially in south China because of its high nutritional content and sweet taste. In August 2023, damping-off disease of approximately 60% of seedlings was observed at a nursery in Zhanjiang, Guangdong Province (E110°17'46″ N21°9'2″). Stems of infected seedlings exhibited symptoms of water-soaked tissue which caused collapse at the base of the stem and sloughing of necrotic root cortex tissue was observed (Figure 1). White aerial mycelia were visible on the surface of the stem and soil at a high relative humidity. Diseased tissues about 0.5 cm2 were taken from the infected roots and stems, surface disinfected with 75% ethanol and 3% hydrogen peroxide solution, each for 1 min, subsequently rinsed in sterile water, and placed on potato dextrose agar (PDA). Plates were incubated at 25 to 28℃ in the dark for 3 days. Coenocytic hyphae grew from all infected roots and stems. Hyphal tip transfers were completed twice, and twelve isolates with the same morphological characteristics were obtained. The colony growth on PDA was ample. Main hyphae are up to 9.5 µm wide. Sporangia were terminal, inflated, branched or unbranched. Encysted zoospores were 7.5 µm in diameter. Oogonia were terminal, globose, smooth and of 16.8 to 27.4 µm (average 21.5 µm) diameter. Oospores were typically spherical, thick-walled, yellowish, 19.7 to 26.3 µm (average 21.1 µm) diameter, wall 1 to 2 µm thick. Antheridia were mostly intercalary, sometimes terminal, broadly sac-shaped, 15.0×19.0 µm (Figure 2). The morphological features were very similar to those of Pythium spp. (Toporek and Keinath 2021). For further identification, the LSU and ITS regions of isolate CCAS-YWGCD (stored in Agricultural Culture Collection of China, ACCC 35633) were amplified and sequenced with using primer pairs LROR/LR7 and ITS1/ITS4, respectively (Gao et al. 2017; White et al. 1990). The resulting sequences were deposited in GenBank (ITS: OR775664; LSU: OR775667). BLASTn results showed 100% sequence similarity with reference sequences of Pythium aphanidermatum (AY598622 for ITS and HQ665084 for LSU). Phylogenetic tree generated from maximum likelihood analysis based on combined LSU and ITS sequence data with MEGA 10.1.8, clustered the oomycete in P. aphanidermatum clade with 100% bootstrap support (Figure 3). Therefore, the oomycete was identified as P. aphanidermatum. To confirm Koch's postulates, six three-month-old seedlings of H. megalanthus (height about 15 cm) were transplanted to 15 cm pots. Six-mm-diameter mycelial plugs obtained from 7-day-old cultures at 25℃ in the dark were buried adjacent to the stem of three unwounded healthy seedlings. Another three seedlings inoculated with PDA agar served as controls. The plants were covered with plastic bags, kept at about 30℃, and watered regularly to keep the soil moisture content high. All inoculated seedlings exhibited symptoms of stems rot and damping-off, Symptoms did not develop on the control seedlings. P. aphanidermatum by morphological and molecular analysis was reisolated from the stems. P. aphanidermatum had been reported worldwide causing disease in many agricultural crops (Qi et al. 2021; Kim et al. 2020), but this is the first report causing damping-off of H. megalanthus seedling in China as well as worldwide, and this disease should be monitored in nursery seedlings.

Phytochemical characterization and biological activities evaluation of Opuntia sp. cladodes

The prickly pear is a plant belonging to the Cactaceae family, and it is the best-known species that has gained significant recognition in recent years. Opuntia sp. cladodes have been traditionally utilized as a functional food and in traditional medicine for treating chronic diseases. Therefore, this study aims to evaluate the antioxidant, antimicrobial, and pharmacological activities of cladode extracts from Opuntia microdasys (Cl1) and Opuntia macrorhiza (Cl2), as well as to identify their phytochemical compounds. The chemical composition of the cladode extracts was analyzed using spectrophotometric methods, while the antioxidant activity was determined through DNA nicking assays. Microdilution assays were employed to assess the antimicrobial activity. Analgesic and anti-inflammatory activities were determined using the acetic acid writhing test in mice and the carrageenan-induced Wistar rat paw edema test. The results revealed that the two extracts of cladodes from Cl1 and Cl2 were characterized by a high phenolic content (58.13 and 44.58 GAE/g of extract, respectively). All the tested extracts exhibited antimicrobial activity against the strains tested, with Minimum Inhibitory Concentration (MIC) values ranging from 0.312 to 5 mg/mL and Minimum Bactericidal Concentration (MBC) values ranging from 1.25 to 10 mg/mL. The cladode extracts of Cl1 and Cl2 at a dose of 300 mg/kg showed a dose-dependent inhibition of acetic acid-induced writhing in mice, with respective values of 64.76 % and 61.91 %. The maximum anti-inflammatory activity of all doses of cladode extracts was observed 5 h after carrageenan-induced paw edema, and all tested doses significantly inhibited the induced inflammation.

A REVIEW: OPUNTIA FICUS-INDICA AS A SOURCE OF BIOACTIVE COMPOUND INGREDIENTS FOR FUNCTIONAL FOODS, NUTRITION, HUMAN DISEASE AND HEALTH

Originally from Mexico, today, prickly pears (Opuntia ficus-indica (L.) Mill.) can be found worldwide, but they are most common in Africa., Australia, and the countries of the Mediterranean. The Cactaceae family, which has more than 1500 species of cactus, includes prickly pears. Additionally, consumers are becoming more and more interested in it because it contains bioactive substances like carotenoids, sterols, polyunsaturated fatty acids, polyphenols, and vitamins that are linked to important biological and functional activities such as effects on antioxidants, inflammation, and hypoglycemia as it prospers in dry and semiarid areas, this plant is very effective in preventing desertification and can be exploited in fields and gardens as a fence. Although it is frequently used today to make culinary products like jams and juices, it is also eaten as a fruit. If one wishes to create novel products with health-promoting properties for food, cosmetics, or pharmaceutical fields, As a feasible wellspring of phytochemicals for practical food sources, natural additions, or nutritional supplements, prickly pears are affordable. Peer Review History: Received 3 December 2023; Revised 25 January 2024; Accepted 6 March; Available online 15 March 2024 Academic Editor: Dr. Sally A. El-Zahaby, Pharos University in Alexandria, Egypt, sally.elzahaby@yahoo.com Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Gehan Fawzy Abdel Raoof Kandeel, Pharmacognosy Department, National Research Centre, Dokki, 12622, Giza, Egypt, gehankandeel9@yahoo.com Dr. Evren Alğin Yapar, Turkish Medicines and Medical Devices Agency, Turkiye, evren.yapar@yahoo.com

First Report of Colletotrichum tropicale Causing Anthracnose on Pitaya (Hylocereus costaricensis) in Brazil.

Pitaya, Hylocereus costaricensis, is a species of the Cactaceae family and originated in the Americas (Ortiz & Livera, 1995). It has been cultivated in Brazil and has shown a great potential for fruit production and is currently present in several markets (Faleiro et al. 2021). In July 2018, infected plants of pitaya with symptoms of anthracnose were obtained from an orchard in Fortaleza, Ceará Brazil, (3°44'24.5"S 38°34'30.8"W), with 50% disease incidence. The symptoms observed consisted of well-defined and depressed stains, that initially appeared as reddish-orange spots and were surrounded by a border of dark-brown color. As the lesion progressed, the center became light brown or whitish in color, with black dots appearing later. Four cladodes were collected with anthracnose symptoms. The pathogen was isolated from symptomatic cladodes, which were surface disinfected with 1% v/v NaClO and 70% v/v ethanol, rinsed with sterile distilled water, transferred onto potato dextrose agar (PDA) medium and incubated under a light/dark (12h/12h) photoperiod. Two isolates were recovered from the lesions on cladodes. Pure cultures were obtained from single conidia produced on colonies grown on PDA medium, using an inoculation needle under a microscope. Colonies on PDA exhibited white aerial mycelia with an orange conidial mass. The colonies were light grey in the front and light orange in the reverse of the plate. Morphological features suggested that the isolates had the same characteristics as previously described for Colletotrichum spp. (Weir et al., 2012). In order to identify the species of the isolates, the genomic DNA of UFCM 0684 and UFCM 0685 isolates was extracted using the CTAB method and the ITS region, TUB2, ACT, GS, GAPDH gene fragments were amplified. PCR products were sequenced and the resulting sequences were submitted to phylogenetic analyses based on maximum likelihood for the combination of the genes. The isolates grouped within Colletotrichum tropicale with 99% bootstrap support. The sequences obtained in this study were deposited in GenBank as ACT (accession no. OL799311, OL799312), TUB2 (OL799313; OL799314), GAPDH (OL799315, OL799316), GS (OL799317; OL799318) and ITS (OL799319; OL799320). After that, the UFCM 0685 isolate was selected to study for further characterization. Conidia (n = 50) were 13.7 (length) × 4.7 μm (width) in average, hyaline, aseptate and cylindrical. To complete Koch's postulates, pathogenicity tests were performed in moist chamber for one week at 25°C with 80% relative humidity on a 12 h fluorescent light/dark photoperiod. The cladodes were wounded using a sterilized needle and inoculated with 10 µl of a conidial suspension (1 × 106 conidia/ml) on three cladodes with five wounds each. The same number of uninoculated cladode was used as control. The experiment was performed twice. Two weeks later, all inoculated cladodes showed necrotic symptoms, which were similar to the symptoms previously observed in the field. The uninoculated cladode remained symptomless. The fungus was reisolated from the inoculated cladode and its morphological characteristics were similar to the original isolate. Colletotrichum tropicale has been reported to cause anthracnose on H. costaricensis in Mexico (Nunez-Garcia et al. 2023), H. undatus, H. monocanthus and H. megalanthus (Evallo et al. 2022). For the best of our knowledge, this is the first report of anthracnose caused by C. tropicale in H. costaricensis in Brazil.

What Is in the Bank? Assessing Persistent Soil Seed Bank Density of Sclerocactus wrightiae (Cactaceae)

Wright fishhook cactus is a small globose cactus endemic to an area of 280,000 ha in south-central Utah and was listed as endangered in October of 1979 by the U.S. Fish and Wildlife Service (USFWS). There is a general paucity of information about this species, and no published data on the seed bank for any species in the genus. Our objective with this study was to provide insight into the established seed bank density for this species. We processed 500 soil samples from various locations near individual cacti and potential neighboring nurse plants. We found that the species had a detectable seed bank of a size similar to other members of the Cactaceae family. Seed bank densities were the highest immediately adjacent to, and downslope from, parent plants. Our data indicate that areas within 20 cm of seed-producing cacti contain by far the greatest density of seeds. These areas should be given special consideration in future management plans for this species.

Antioxidant Activity and Seasonal Variations in the Composition of Insoluble Fiber from the Cladodes of Opuntia ficus-indica (L.) Miller: Development of New Extraction Procedures to Improve Fiber Yield.

Opuntia ficus-indica (L.) Miller is a plant belonging to the Cactaceae family adapted to live in environments characterized by long periods of drought and arid or desert climates. This plant is characterized by an aerial part composed of structures transformed by branches, called "cladodes", which are essential to reduce excessive perspiration of water and appear covered with thorns. The composition of the cladodes includes water, polysaccharides, fiber, proteins, vitamins, fatty acids, sterols, polyphenols, and minerals. The main purposes of this scientific work are (a) to compare the insoluble fiber (IF) extracted from the cladodes of O. ficus-indica belonging to the same plant but collected in different seasonal periods (winter and summer) and develop new extraction protocols that are able to improve the yield obtained and (b) evaluate the antioxidant potential of the fiber and study possible variations as a result of the extraction protocol chosen. The first objective was achieved (1) by measuring the amount of IF extracted from cladodes harvested in winter and summer (CW and CS, respectively) and (2) by modifying three variables involved in the fiber extraction protocol. To achieve the second objective, the following experiments were carried out: (1) measurement of the antioxidant potential of IF in CW and CS; (2) measurement of cellular reactive oxygen species; (3) measurement of the activity of some antioxidant enzymes; and (4) comparison of the polyphenol content in CW and CS. In conclusion, the results obtained showed that the IF extraction process can be improved, achieving a uniform yield regardless of seasonality; the antioxidant effect may vary depending on the extraction protocol.

Trends in research on cacti: the food of the future.

Cacti are a distinguished group of plants that stand out for their great nutritional values, diverse uses, and unique morphology, allowing them to grow and thrive under different conditions such as dry, xeric, and even low-temperature environments. The world is going through significant climate changes that are affecting the agriculture system. Therefore, sustainable and multifunctional crops, as many species of the Cactaceae family are, might be a good alternative in the near future. In this work, the uses of cacti in human food were analyzed through a scientific prospection from the point of view of their temporal and spatial distribution and potential uses. Brazil is the country with more publications related to the scope of this work, followed by Mexico. The presence of cacti in these countries can influence their interest in these species, which might reflect the results encountered in this study. The uses and ethnobotanical applications of cacti vary in different countries worldwide. Cactus is consumed fresh (in salads), in preparations (jams and sweets), and juices, being also present in traditional dishes in countries like Mexico. This study emphasizes cacti's importance in people's diets and ongoing world changes. Their ability to thrive even in hot environments with low water resources will lead to a greater focus on these species in the upcoming years. Furthermore, these plants have great flavor and contain several beneficial chemical compounds with desirable nutritional and health properties. Therefore, knowledge dissemination combined with technological innovations will allow greater use of these multifunctional species for human consumption. © 2024 Society of Chemical Industry.

The evolutionary history and distribution of cactus germplasm resources, as well as potential domestication under a changing climate

AbstractThe angiosperm family Cactaceae, a member of the Caryophyllales, is a large and diverse group of stem succulents comprising 1,438–1,870 species within approximately 130 genera predominantly distributed from northern Canada to Patagonia. Four centers of diversity from Central and North America (Chihuahua, Puebla‐Oaxaca, Sonora‐Sinaloan, and Jalisco) and three centers of diversity from South America (Southern Central Andes, Caatinga, and Mara Atlantica) have played a pivotal role in disbursing cacti around the globe. Mexico is considered the richest area in cacti species with close to 563 species grouped into 50 genera. Approximately 118 species have been domesticated by Mesoamerican people as food crops and for ornamental purposes. Cacti inhabit a wide range of ecosystems and climate regions, ranging from tropical to subtropical and from arid to semiarid regions. Species belonging to the genus Opuntia are the major food crop producers in the family. Cacti have derived characteristics from familial synapomorphies within the Caryophyllales. Reproduction occurs through pollination facilitated by birds, bats, bees, and other insects. Climate variability, whether natural or human‐induced threatens global crop production including high temperatures, salinity, drought, flood, changes in soil pH, and urbanization. Cacti have several adaptations that are important for coping with abiotic stresses, such as crassulacean acid metabolism (CAM photosynthesis), as well as modifications to root and stem physiological pathways. This review aims to provide a comprehensive view of the fruit crops in Cactaceae, including their evolution, worldwide distribution, and the environmental factors impacting cultivation.