Cardon cacti (Pachycereus pringlei) are an important forest resource in Baja California Sur (B.C.S.), playing a vital role in Mexico's arid zones and carrying ecological, cultural, floristic, and social significance. Over the past two decades, fungal diseases, presumably linked to a necrotic spot syndrome (NSS), have been recorded in the region, causing significant damage to wild populations of this iconic columnar cactus. The causative agents were identified through morphological and molecular characterization, and disease pathogenicity was assessed by measuring severity, incidence, and spatiotemporal recurrence. We identify Alternaria alternata and Phoma sp. associated with necrotic spots on wild cardons, which cause dark brown spots, pustules with a chlorotic halo, small chancres, and concentric circle lesions. Disease intensity of 52.3% can be considered high, with an incidence of 65.3% and a severity of 39.5%. Severity estimates from two independent methods (diagrammatic and lesion range-based) were similar, indicating that both methods can be used to estimate severity. To verify pathogenicity, experimental inoculations were performed to satisfy Koch's postulates, and the resulting symptoms were similar to those observed in the field. This study confirms the presence and spread of fungal diseases in cardon cacti and identifies Alternaria alternata and Phoma sp. as causal agents of the disease NSS. This study contributes to the development of conceptual strategies for preventive actions against fungal diseases in giant cardon cacti in arid zones of B.C.S., Mexico, and worldwide.
Humic and fulvic acids are widely recognized as biostimulants capable of improving nutrient availability and plant growth. This study evaluated the effects of organic amendments and humic substances on the production of tender cladodes of Opuntia ficus-indica (L.) Mill. The experiment was conducted under a randomized complete block design with four replicates and 15 treatment combinations derived from three substrate conditions (unamended soil, bovine manure, and poultry manure) and five humic/fulvic acid treatments (no acid application, humic acid at 2.5 and 5.0 g L-1, and fulvic acid at 2.5 and 5.0 g L-1). Organic amendments were applied once at planting at a rate equivalent to 50 t ha-1, whereas humic and fulvic acids were applied periodically through irrigation. Tender cladodes were harvested at 20 +/- 1 cm in length, and cumulative production and number of tender cladodes were recorded throughout the production cycle. Poultry manure significantly increased both cumulative tender cladode production and the number of tender cladodes compared with the unamended soil treatment. Fulvic acid application also resulted in greater production and a higher number of tender cladodes than humic acid and the no-acid treatment. The combination of poultry manure and fulvic acid produced the highest number of tender cladodes. These results indicate that poultry manure and fulvic acid constitute effective management alternatives for improving tender cladode production of Opuntia ficusindica under calcareous soil conditions.
Opuntia ficus-indica is renowned for its resilience to adverse environmental conditions. However, it remains susceptible to various diseases caused by both biotic and abiotic factors. Among these diseases, cladode thickening represents a significant agronomic limitation. Although phytoplasmas and viruses have been suggested as potential causal agents, its etiology remains unknown. This study aimed to characterize the structure, diversity, and phylogenetic relationships of bacterial communities across different compartments of cultivated O. ficus-indica, comparing healthy and thickened plants during the rainy and dry seasons through 16S rRNA gene amplicon sequencing, to assess the potential role of bacteria in the etiology of this disease. Five ecological compartments were analyzed: soil, rhizosphere, root tissue, phyllosphere, and cladode tissue. The V3-V4 region of the 16S rRNA gene was sequenced from bacterial communities, and bioinformatic analyses were conducted using the Mothur pipeline. Soil and root compartments exhibited the highest alpha diversity. This is due to their role as reservoirs of stable and functionally diverse microbial communities. Aerial compartments, on the other hand, showed lower diversity. The structure of bacterial communities in the phyllosphere, cladode tissue, and rhizosphere varied mainly according to the health status of the plant, while soil and root communities were influenced by environmental conditions. In thickened plants, the bacterial composition was similar across compartments, while in healthy plants, the communities were more distinct and compartment specific. Seasonal dynamics shaped the distribution of bacterial taxa across compartments: fewer taxa were shared during the rainy season, while a greater number of taxa were shared across multiple compartments under dry conditions, suggesting a potential role in adaptation to water-limited environments. Despite these compositional differences, no specific taxon could be directly linked to the etiology of the thickening disorder.
Peniocereus greggii (Engelm.) Britton & Rose is a species listed as Subject to Special Protection (Pr) under Mexican standards, with significant ecological value in the Chihuahuan Desert, yet information regarding its propagation remains scarce. This study evaluated the effects of seed age (fresh vs. 7-year storage), temperature (constant 24 degrees C vs. fluctuating 30-37 degrees C), and scarification treatments (H2SO4 at 40% and 50%, mechanical incision, and control) on germination. A three-way ANOVA revealed significant differences for all factors and a significant interaction between seed age and scarification. Scarification alone did not improve germination; acid treatment (H2SO4) effectively inhibited germination, while mechanical incision underperformed the control. Germination was significantly higher in aged 2016 seeds than in 2022 seeds, and was strictly higher under a moderate, constant temperature (24 degrees C) than under fluctuating high temperatures. These results provide solid inferential evidence that P. greggii seeds possess physiological dormancy that is naturally alleviated by after-ripening. Consequently, artificial scarification is unnecessary and detrimental. For ex situ conservation, we recommend extended dry storage of seeds, followed by sowing under moderate temperature conditions (24 degrees C), and strictly avoiding physical or chemical modifications to the seed coat.
Plants from the Cactaceae family can survive under extreme environmental conditions due to their Crassulacean Acid Metabolism (CAM). However, Opuntia ficus-indica, an economically important species of this family, is affected by various pests and diseases, with cladode thickening being one of the most frequent problems. Although some studies have linked this disorder to phytoplasmas and viruses, its etiology remains uncertain. Therefore, exploring other microorganisms that may act as pathogenic agents or serve as indicators of plant health could provide further insight into this disease. The objective of this study was to describe the composition, diversity, and phylogenetic relationships of fungal communities in different compartments of thickened and healthy O. ficus-indica plants, through ITS2 region sequencing during the rainy and dry seasons. Thickened and healthy O. ficus-indica plants were collected during the rainy and dry seasons in San Miguel Atlamajac, Temascalapa, State of Mexico. Samples from five plant compartments (soil, rhizosphere, root tissue, phyllosphere, and cladode tissue) were analyzed using metagenomics to identify, through the ITS2 region, the fungal communities present in each condition (plant health status and season). Data were processed with the Mothur pipeline to evaluate the fungal diversity and taxonomic composition. Alpha diversity varied across compartments, with soil and rhizosphere harboring the richest and most diverse fungal communities, reflecting the structural heterogeneity that characterizes these environments, whereas cladode tissue showed the lowest diversity values. Fungal communities in the phyllosphere and root tissue were shaped mainly by plant thickening conditions, while cladode tissue, rhizosphere, and soil communities were strongly influenced by seasonal variation. Fungal community composition differed between thickened and healthy plants across all sampled compartments: thickened plants were consistently associated with members of the order Pleosporales, while healthy plants showed a higher relative abundance of Plectosphaerellaceae (order Glomerellales) in belowground compartments, with no clear predominance of a specific fungal group in aerial compartments. Despite these compositional differences, no specific taxon could be directly linked to the etiology of the thickening disorder.
Opuntia streptacantha, or nopal cardon, is a plant species belonging to the Cactaceae family. Its fruit (prickly pear) ranges in color from red to violet. It contains carbohydrates, proteins, dietary fiber, minerals, and peel rich in antioxidant compounds such as polyphenols, flavonoids, and betalains. The use of peels, an underutilized residue, represents a cost-effective alternative to obtain bioactive compounds of food interest, while promoting the health of the regional population through the development of functional foods. This research aimed to develop an ice cream enriched with antioxidant extracts from the Opuntia streptacantha fruit peels, sweetened with Stevia rebaudiana, and to determine, through sensory analysis, the extract concentration most accepted by consumers. Additionally, proximate chemical analysis, antioxidant capacity, and shelf-life studies were conducted. Three ice cream formulations were prepared with peel extracts (0.5, 1, and 1.5%). Based on sensory analysis and phytochemical concentration, the stevia-sweetened ice cream with 1.5% extract was selected for antioxidant capacity evaluation. The stevia ice cream's proximate composition and sensory evaluation (global hedonic rating of 81.2) was determined, and a predicted shelf life of 6.8 and 4.4 months at-18 and-6 degrees C, respectively. Consequently, it was considered the most promising formulation.
Prickly pear cactus (Opuntia ficus-indica) is widely consumed fresh due to its nutritional value, functional properties, and recognized health benefits. Although traditionally considered a low-input crop, the increasing dependence on chemical fertilizers has raised production costs and environmental concerns, prompting the exploration of sustainable alternatives such as plant growth-promoting rhizobacteria (PGPR). These microorganisms can enhance plant performance through multiple mechanisms, including phytohormone production, biological nitrogen fixation, nutrient solubilization, and improved nutrient use efficiency. This study aimed to evaluate agronomic traits, quality attributes, and mineral composition of cactus cladodes inoculated with native PGPR under reduced chemical nitrogen fertilization. The experiment was conducted under open-field conditions using a randomized complete block design arranged in a 3 x 2 factorial scheme. Enterobacter bugandensis (C1), Achromobacter xylosoxidans (C2), and Pseudomonas putida (C3) were applied individually and in combination at 106 CFU mL-1, with nitrogen fertilization supplied at 50% and 100% of the standard dose. Inoculation with E. bugandensis (C1) and the C1 + C3 combination was associated with a higher number of cladodes per plant, suggesting stimulation of vegetative growth under field conditions. Regarding mineral composition, treatments including P. putida showed higher concentrations of phosphorus, potassium, magnesium, and iron in cladodes, indicating improved nutrient acquisition and internal nutrient balance. Additionally, the combination of A. xylosoxidans + P. putida under reduced nitrogen fertilization was associated with increased sugar accumulation in cladodes, reflecting potential metabolic adjustments related to carbon allocation. Overall, the results indicate that inoculation with PGPR can contribute to maintaining agronomic performance and improving the nutritional quality of Opuntia ficus-indica while reducing chemical nitrogen inputs, supporting their use as a sustainable strategy for cactus production in arid and semi-arid environments.
Opuntia spp. is a strategic crop for arid and semi-arid regions due to its high drought tolerance and widespread cultivation; however, the management of postharvest and pruning residues remains a challenge for sustainable production systems. This study aimed to evaluate the circular valorization of nopal (Opuntia spp.) waste through semi-continuous anaerobic digestion, with a primary focus on digestate quality, agronomic relevance, and environmental implications rather than on energy maximization. Reactor operation exhibited a clearly defined pseudo-steady-state (PSS) period characterized by stable methane production (1.85-2.35 L CH4 d-1), methane concentration (65-67%), and reactor pH (approximate to 7.6), enabling reliable digestate characterization. Digestate produced during the PSS met physicochemical, maturity, and microbiological criteria established by Mexican regulatory standards, supporting its suitability for agricultural reuse. Agronomic validation showed that partial substitution of synthetic fertilizers with digestate improved crop performance when applied at optimized rates; in hydroponic lettuce, a 50% substitution level increased fresh biomass by 15% compared to the control, whereas higher substitution rates reduced growth. A cradle-to-gate carbon footprint assessment indicated a net reduction in greenhouse gas emissions, primarily driven by avoided synthetic fertilizer production. Overall, this integrated evaluation provides a proof-of-concept for the circular valorization of Opuntia-derived residues through anaerobic digestion, supporting sustainable nutrient management strategies for CAM crops and agricultural systems in arid and semi-arid regions.
Cactus pear fruit (Opuntia spp.) is an increasingly popular exotic fruit grown in arid and semi-arid regions of Mexico and around the world. This fruit has gained global interest because of its nutritional value, human health benefits, and contribution to food security in marginalized regions. Cactus pear is a nonclimacteric fruit; therefore, it is either harvested at the color break (veraison) or ripe fruit (ready-to-eat) stage, depending on the intended market. However, previous postharvest studies have not examined the combination of fruit ripening stage (FRS) with different fruit mass loss (FML) thresholds. This research work aimed the influence of FRS (veraison or ripe fruit) and FML thresholds (5 and 8%) on some quality attributes of white and pigmented cactus pear fruit stored at room temperature. At harvest, veraison fruit of all cultivars had greater flesh firmness but less total soluble solids, peel dry matter and pulp dry matter than ripe fruit, except in 'Roja Lisa'. The time to reach each FML threshold varied significantly among However, during storage, the FRS at both FML thresholds was similar in all cactus pear fruits, except for Amarilla Olorosa fruit at 8% FML. Fruit decay incidence was not influenced by cultivar, FML, or FRS. After reaching 5% FML, fruit appearance began to deteriorate in all fruits. FML of 8% reduced fruit dimensions, but the other quality attributes responded depending on the cactus pear fruits. In conclusion, postharvest handling during storage depends on the specific cultivar. However, the results indicate that the FML threshold for pigmented cultivars can be set at 5% FML. This information is important for postharvest handling and marketing.
Currently, information on the phytochemical composition and functional activity of Opuntia genus stamens remains limited, but recent studies have shown promising results. Further research on this topic is necessary to apply it to the differentiation between species and evaluate their chemical richness and antioxidant potential. In this context, the present study analyzed the chemical profile and antioxidant activity of the stamens of four Opuntia species. Aqueous extraction with methanol was performed, and various phytochemicals, including pigments, phenolic compounds, flavonoids, condensed tannins, and reducing sugars, were quantified using spectrophotometric methods. Antioxidant activity was also assessed using FRAP and DPPH assays. Principal components analysis explained 97.9% of the total variation. Reducing sugars strongly correlated with component 1 (0.99), while chlorophyll b (0.67), the antioxidant activity as determined by FRAP (0.45), and carotenoids (0.38) were associated with component 2. The stamens of O. microdasys exhibited the highest levels of reducing sugars and carotenoids, while O. macrocentra and O. arenaria showed the lowest values, respectively. The highest antioxidant capacity (FRAP) was observed in O. arenaria and O. microdasys, and the lowest in O. engelmannii. Overall, the results suggest that the stamens of O. microdasys constitute a promising source of bioactive compounds, with potential for applications in pharmacology and nutrition.
Prickly pear (Opuntia spp.) is a fruit with high nutritional and functional value, but it is highly perishable. Parthenocarpic cactus pear fruits (CP30-P, CP40-P) are a viable commercial alternative because they have almost imperceptible seeds and longer shelf life. However, their response to cold storage, compared to pollinated prickly pear fruits, has not been reported. This study evaluated the effect of cold storage at 10 +/- 1 degrees C and 85 +/- 2% relative humidity on the quality of parthenocarpic (CP30-P and CP40-P) and pollinated (CP30 and CP40) prickly pear fruits. The variables such as weight loss, total soluble solids (degrees Brix), acidity, antioxidant activity, electrolyte leakage, and enzymatic activity (CAT and APX) were assessed during cold storage. The parthenocarpic fruits had higher weight loss compared to pollinated fruits (15% vs. 8%), greater electrolyte leakage, and lower catalase activity, indicating increased susceptibility to water loss and altered cell membrane permeability. However, these fruits also exhibited higher antioxidant activity at 30 and 45 days, suggesting a physiological response to oxidative stress induced by cold storage. No significant changes were observed in total soluble solids or titratable acidity, demonstrating that these parameters remained stable throughout the study. Cold storage is an effective strategy to preserve the postharvest quality of prickly pear, particularly regarding composition stability. Nevertheless, parthenocarpic fruits require additional strategies to minimize dehydration and improve resistance under prolonged storage conditions.
The genus Rhipsalis belongs to the Cactaceae family and comprises 33 registered species that exhibit unique biological and evolutionary characteristics, reflecting their wide biogeographical distribution. The objective of the present study was to evaluate the current state and research trends on this genus. A bibliometric analysis of 110 records published from 2001 to 2024 in Scopus and Web of Science (WOS) was performed using the R Bibliometrix package. Co-occurrence networks, collaboration networks, and factor analyses were used to study authors, countries, keywords, and references. The results do not suggest a clear trend in scientific output or the number of citations; however, the publication of reports remained constant throughout the period. The primary source of publications is Brazilian institutions, which exhibit a high rate of self-collaboration. Among the 25 most cited references, topics related to biology and cactus systematics predominate. Three thematic clusters correlated with the keywords were identified: the first on ecology and evolution, the second on ethnobotanical and pharmacological uses, and the third on molecular and phylogenetic studies. The results suggest that the field may be entering a consolidation phase, focused on resolving complex taxonomic and evolutionary questions while simultaneously prompting metabolite bioprospecting with therapeutic potential. Active lines of research are using Rhipsalis baccifera, considered a relevant species within the genus, as a model organism. Phytochemical characterization is being conducted to support its use in traditional medicine and its antitumor, antimicrobial, and anti-inflammatory potential. This study synthesizes the main research advances in genetics, offering a framework to guide future explorations and their potential applications.
The production of prickly pear in the State of Mexico covers an area of 15,953 ha with a yield of 11.3 t ha-1. However, the prickly pear production chain faces technical, social, and economic problems that are reflected in low prices and reduced profitability, where organic prickly pear production is seen as an alternative to the above problems, as well as to the growing demand for this organic fruit nationally and internationally. This research consisted of measuring the productivity and profitability of prickly pear cactus in San Mart & iacute;n de las Pir & aacute;mides and Axapusco, State of Mexico, during the 2019 production cycle. To evaluate productivity, the AxB factorial experimental design with random block arrangement was used, and to determine profitability, the following expression was used: CT=Px X. Based on the analysis of the results, organic production had the highest number of productive cladodes (83), number of fruits per plant (242), and total fruit weight (140.9 g), variables that defined the yield at 21.5 t ha-1 compared to intermediate and conventional management (8.2 and 11.8 t ha-1). In addition, organic production obtained a profitability of 150.35% and 88.92% when land rent is included, compared to the intermediate and conventional approaches, which reached 44.14% and 48.15%, respectively, and-22.04% and-10.63%, taking land rent into account. It is concluded that organic production improves the quality of prickly pear in the long term and leads to high yields, highlighting that it generates greater opportunities to address the low profitability of the crop in the region.
The cactus pear is a plant that can survive and produce under the soil and climatic conditions of tropical regions, but its management is still relatively little known in the Brazilian savannah. The objective of this study was to evaluate management alternatives for the cactus pear variety Doce, subjected to different cutting intensities, preserving the matrix, primary or secondary cladodes, and two harvest ages (annual and biennial), under rainfed conditions in the Brazilian savannah. A completely randomized design was adopted in a 3 x 2 factorial scheme, with eight replications. Morphometric and production variables, chemical composition, as well as macro and micronutrient contents were assessed. Greater amounts of green forage mass yield (GFMY) and dry forage mass yield (DFMY) were found when up to the primary cladode was preserved, but the crude protein content was like that found in the matrix cladode cutting intensity. Managing the cactus pear under biennial harvest provided higher height, GFMY, DFMY, potassium, and micronutrient accumulation. The management alternative that provides the most benefits in terms of agronomic characteristics and production is the one that preserves up to the primary cladode associated with biennial harvest. In addition, biennial harvest provides better chemical composition and greater accumulation of macro and micronutrients in cactus pear cultivar Doce.
The impact of climate change on food production systems affects agrifood safety and, consequently, national food sovereignty. Thus, food systems must adopt new practices, including the modification of crop selection. Within this context, agro-climatic suitability studies for species adapted to warmer temperatures and drought are crucial. Opuntia ficus-indica is a tolerant crop, notable for its nutritional and cultural significance. For that reason, the objective of this study was to determine its agro-climatic suitability using annual precipitation, mean temperature, and minimum temperature for the current scenario (1990-2020) and the 2040-2070 period, defined by the Shared Socioeconomic Pathways (SSP) 2 and 5. The results showed a general decrease in the proportion of highly suitable territory, with the notable exception of Zacatecas. This state, known as a major national producer of this crop, exhibited a 17% increase in the proportion of suitable territory in the 2040-2070 scenarios for both SSPs compared to the current scenario. The model's validity was confirmed via Chi-square (chi 2) and Frequency Ratio (FR) analysis for current scenario. Overall, this research indicates a reduction in optimal agro-climatic conditions for O. ficus-indica cultivation in the north-central states of Mexico.
Opuntia albicarpa is an endemic species of Mexico with cultural and economic importance. The opuntia fruits, named prickly pear or tunas, are rich in glucose, fructose, and sucrose. The objective of this study was to contrast morphological changes in the development and ripening of the fruits, and detect genes involved through transcriptomics to identify some important metabolic pathways. Total RNA from fruits of three developmental stages was sequenced in paired-end mode with Illumina technology. High-quality reads were assembled de novo and annotated against the Swissprot protein database, and differentially expressed genes between the three stages were determined. The de novo ensembled transcriptome was represented by 198,958 transcripts (41.95% GC content). A total of 22,460 and 39,683 sequences were annotated with Blastx and Blastp, respectively. In addition, 10,106 genes were identified from Blastx and 11,781 genes with Blastp. In the differential expression analysis for the comparison 60 days after flowering vs. the start of ripening, 1572 transcripts were upregulated and 412 downregulated, in 60 days after flowering vs. ripened fruit, there was an upregulation of 1265 transcripts and 454 downregulated, and at the start of ripening vs ripened fruit, 96 transcripts were upregulated and 745 downregulated. The pathways of carbohydrate metabolism and flavonoid biosynthesis during the development and ripening of fruits were analyzed to quantify the genes involved. The results can be used for genetic and molecular studies on the genus Opuntia and better understand its biology.
Opuntia ficus-indica is a succulent plant of Cactaceae family, easily distinguished by the presence of characterized branches called "cladodes". The latter are rich in bioactive components such as dietary fibers, vitamins and polyphenols, and thus could be considered as a functional food or food ingredient. The main objectives of this study are (a) to investigate the fermentability of Opuntia ficus-indica cladodes by a probiotic strain Lactiplantibacillus plantarum F2, (b) to determine the effect of the cladodes on the beneficial effects of the probiotic strain, and (c) to examine the influence of the plant age, sterilization method and the concentration on the observed effects. For this, nine concentrations of either young (3-6 months old) or aged (>1-year-old) cladodes were tested. Firstly, the cladodes were examined on their physicochemical characteristics. Then, their effect on bacterial growth, surface properties and adhesion, antibacterial and anti-biofilm activities and antioxidant and cholesterol lowering potentials were investigated. The results showed an enhancement in growth and strengthening of the probiotic strain performances (higher antibacterial, adhesion, anti-biofilm, antioxidant and cholesterol lowering activities). The effects of the powder were recorded in age-, sterilization method and concentration-dependent manners. In general, most pronounced effects were observed with young cladodes, in filtered macerates and at high concentrations. Nevertheless, opposite observation was noted for the antioxidant potential, which was better in the presence of aged cladodes. In whole the results gathered in this work showed a synergistic effect between the probiotic strain and the O. ficus-indica cladodes macerate.
This study evaluated an innovative protocol for the accelerated vegetative propagation of Euphorbia antisyphilitica (candelilla), an endemic shrub threatened by unsustainable harvesting in Mexico's arid regions. Three propagation systems were compared, combining hydroponics, nursery, and openfield approaches with natural biostimulants and conventional rooting agents. Hydroponics with a natural biostimulant blend of Rosmarinus officinalis, Lens culinaris and Cinnamomum zeylanicum extracts yielded the fastest and most vigorous rooting, achieving functional root systems within four weeks, a reduction of over 90% compared to traditional timelines. Survival exceeded 99%, demonstrating the reliability of this approach. In contrast, indolebutyric acid proved ineffective in hydroponics due to its instability in aqueous media. Nursery propagation highlighted the importance of substrate selection, with native mountain soil outperforming commercial and agricultural substrates, likely due to its favorable pH and natural mycorrhizal associations. Overall, the integration of hydroponics and natural biostimulants provided the most sustainable and reproducible protocol, offering significant advantages for ecological restoration, ex situ conservation, and community-based management of arid ecosystems. These results establish a scientific foundation for scaling up vegetative propagation of candelilla and similar species, reducing dependence on wild populations while promoting restoration in degraded arid landscapes.
Dactylopius opuntiae is a major pest of prickly pear crops and has therefore been extensively studied with the aim of controlling its proliferation. However, it has largely been disregarded as a potential natural red pigment source, despite producing carminic acid (CA), as does Dactylopius coccus, albeit in lower amounts. CA, an anthraquinone compound, is highly valued for its strong coloring capacity and commercial relevance in the food, cosmetic, and pharmaceutical industries. Conventional CA extraction methods are often constrained by long processing times and limited environmental sustainability. In this context, ultrasound-assisted extraction (UAE) has emerged as an efficient and eco-friendly alternative, offering improved extraction yields. This study aimed to optimize the UAE of CA from D. opuntiae and maximize extract yield. A Box-Behnken experimental design was applied, testing temperatures of 20, 40, and 60 degrees C; extraction times of 3, 6, and 9 min; and ultrasound amplitudes of 20, 30, and 40%. The highest CA concentration (14.76 +/- 0.32%) was obtained at 60 degrees C, 3 min of sonication, and 20% amplitude, representing a 7.45% increase compared with the conventional method. These findings demonstrate that UAE enables higher CA yields in significantly shorter processing times, providing a sustainable strategy to transform D. opuntiae from an agricultural pest into a valuable natural pigment source.
Cactus pear (Opuntia ficus-indica) plays a crucial role in Tigray, Ethiopia, serving as a vital source of food, fodder, and household income. In 2004, the cochineal insect (Dactylopius coccus) was introduced with the intention of enhancing the economic value of cactus pear. However, the insect quickly became invasive, decimating vast areas of cactus pear and severely impacting the livelihoods of local communities. The rapid spread of the cochineal insect was largely due to a lack of prior knowledge about its biology and the absence of environmental impact assessments before its introduction. Additionally, the out-grower scheme associated with the cochineal trade contributed to the unregulated spread of the pest, both natural and through human activity. Favorable conditions—such as prolonged dry spells, an abundance of cactus pear, and a lack of natural predators—further accelerated the insect’s colonization and expansion. Attempts to control the infestation through community mobilization and insecticide applications proved largely ineffective. The suspension of cochineal harvesting is also believed to have worsened the situation. Today, over 75% of the cactus pear cultivation area is affected. Surveys conducted over several years have identified three indigenous predators of the cochineal insect, but their populations remain low. The laboratory evaluations of exotic natural enemies have not shown promising results. Similarly, efforts to find resistance within local cactus pear populations have been unsuccessful. On a more positive note, four introduced cactus pear varieties have demonstrated strong resistance in both laboratory and field conditions. In addition, some farmers have developed effective local management practices for cochineal control. The combined application of resistant cactus pear varieties and these locally developed practices offers a practical pathway to prevent destruction of the crop. Although complete eradication of the cochineal insect may not be feasible, the challenge presents a unique opportunity, producing cochineal under controlled conditions could position Ethiopia as a strong competitor in the global cochineal market. This paper explores the economic and environmental impacts of the cochineal invasion, reviews the responses and lessons learned, and presents recommendations for sustainable pest management.
