Opuntia Research Articles

Functional properties of cactus pear mucilage: gelling and spherification

Functional properties of cactus pear mucilage: gelling and spherification

Gelling potential of native cactus pear mucilage

Gelling potential of native cactus pear mucilage

Size and harvest time of cladodes modulate the composition and physicochemical stability of prickly pear cactus mucilage

The objective was to carry out a physicochemical characterization of the mucilage obtained from different sizes of cladodes harvested at different times. Nopalea cochenillifera Salm Dyck cladodes were collected in two sizes (100 to 230 and 240 to 300 mm), at two different times (6 am and 8 pm), and processed for mucilage extraction. This was dried in an oven, and then hydrated and kept at 5 °C for 12 days. The mucilage yield after harvest was quantified, in addition to the characterization of the main bands in the infrared region. In the mucilage, the following physicochemical analyzes were performed: K+ and Na+ content, electrical conductivity, titratable acidity, pH, total phenolic compounds, vitamin C, total soluble solids, total soluble carbohydrates, total soluble proteins after harvest (day 0), and to the 12 days of storage at 5 ºC. Correlation between the variables was determined through principal component analysis (PCA). The highest mucilage yield was obtained in cladodes harvested at 6 am, regardless of size. The 6 am harvest showed higher acidity and protein content and lower concentrations of soluble solids, EC, Na+, K+, vitamin C, carbohydrates, and phenolic compounds. In conservation, the mucilage of the cladodes with sizes between 100 and 230 mm and the harvest at 6 am showed greater stability. Principal component analysis (PCA) showed a tendency of formed groups between different sizes, harvest times, and conservation days, indicating that different conditions for obtaining the cladodes result in differences in the composition and stability of the mucilage. Thus, the results show that, in addition to the climatic conditions, as proposed by other authors, the harvest time and the size of the cladode modulate the physicochemical and important ion composition and stability, which can change the technological and industrial applications of mucilage.

Preparation and characterization of a biodegradable film from cactus Nopalea sp.

The increasing use of natural biodegradable polymers is a consequence of the concern of society with sustainability. Mucilage of forage cactus of the genus Nopalea is an attractive polymer matrix for the composition of edible films. Most studies on biodegradable films are carried out with the genus Opuntia. This makes Nopalea an important source of interest in the investigation of film formation. The objective was to study the formulation of films and evaluation of physical, optical, and mechanical characteristics of clones of Nopalea and Opuntia, through the addition of water and glycerol. The mucilage was extracted from cladodes of Nopalea cochenillifera Salm Dyck: clones IPA Sertânia (IPA) and Miúda (MIU); and, from Opuntia stricta [Haw.] Haw., clone Orelha de Elefante Mexicana (OEM). The powdered mucilage was hydrated and vacuum filtered, followed by the formulation of the films, without glycerol (just water) and with the addition of glycerol at 15%, 25%, and 14% for IPA, MIU, and OEM clones, respectively. The yield of powdered mucilage was higher for Nopalea. Optical tests with the films revealed that the addition of glycerol generated slightly yellow films (positive b* values), with less transparency than the control films, regardless of the clone and higher L* value in IPA clone films. Moisture content and thickness were increased when glycerol was added. All films, with and without glycerol, showed high water solubility. The microstructure revealed that the films with glycerol presented more compact, smooth, and linear surfaces, forming a homogeneous network. The FTIR spectra revealed that the glycerol films showed the same profile as the control samples, but with higher absorption intensities in some bands. The results found in the present work evidence the potential of the genus Nopalea to produce biodegradable films, as already widely known for the genus Opuntia.

Genetic relations among Moroccan Opuntia genotypes with different degrees of resistance to Dactylopius opuntiae

Genetic diversity and relationship among a set of 18 cactus pear genotypes, with different degrees of resistance to cochineal scale insect (Dactylopius opuntiae), was estimated using eight simple sequence repeat (SSR) markers. The genotypes used belong to four Opuntia species (O. engelmanii, O. ficus indica, O. robusta, and o. dillenii). The analysis revealed a total number of 56 alleles (Mean = 7) and an average genetic diversity index of 0.76 with genetic distances ranging from 0.00 to 1.00 at eight microsatellite loci in 18 Moroccan cactus pear genotypes. All microsatellites used were found to be highly informative, with mean polymorphic information content (PIC) estimated at 0.72. Genetic relationship estimated using the neighbor-joining (NJ) method and the principal coordinate analysis (PCoA), showed that the 18 genotypes were successfully assigned to four clusters, separated according to their taxonomy distribution and their levels of resistance to D. opuntiae. The results of this study demonstrated that the Moroccan cactus pear genotypes evaluated are highly divergent and that these genotypes will be useful for future crossing programs to improve the genetic diversity in Opuntia for resistance to D. opuntiae.

Thermotolerance of Greenshell™ mussel spat (Perna canaliculus) improved by prickly pear (Opuntia ficus indica) treatments

Cultured Greenshell™ mussels (Perna canaliculus) are exposed to biotic and abiotic stresses, all of which can negatively impact growth, fecundity, and survival. These impacts are especially pronounced in sensitive larval and spat stages and may result in substantial losses when spat are transferred from hatchery to grow-out farms. Immersion in solutions of plant extracts have been shown to improve stress tolerance in certain aquatic species and may offer new husbandry and market access opportunities, e.g., more amenable to organic farming practices. Here the efficacy of immersing P. canaliculus spat in ‘high’ or ‘low’ concentrations of prickly pear cactus (Opuntia ficus indica) solutions was examined. Solutions were made from either dry cactus leaf powder i.e., 4.5 (low) or 45 (high) g L−1 or cactus fruit extract (4 μl or 40 μl L−1) and mussels immersed for 1 h to stimulate potential defence mechanisms within mussels prior to acute thermal challenge.Following a subsequent 1 h thermal shock, the predicted 50% survival temperature (LT50) was raised following pre-treatment with O. ficus indica solutions. However, higher resilience to thermal stress was evident in P. canaliculus spat immersed in low concentration solutions of O. ficus indica powder (LT50 = 32.3 °C) and extracts (LT50 = 32.4 °C) compared to spat in immersed in higher concentrations (i.e., LT50 = 31.8 °C ‘Powder’ and 31.4 °C ‘Extract’ respectively) and to naïve controls (LT50 = 30.7 °C). The results provide evidence for the potential for bioactive plant extracts to augment physiological resilience in a shellfish species. While internal biochemical validation is required, the straightforward exposure protocols applied here would be readily transferrable into commercial hatchery culture methods for P. canaliculus.

Effective removal of cationic dye on activated carbon made from cactus fruit peels: a combined experimental and theoretical study.

This article investigates experimentally and theoretically the adsorption of Basic Red 46 cationic dye (BR46) using activated carbon generated from cactus fruit peels (ACCFP). The prepared adsorbent was characterized by different analytical tools showing a good surface for the uptake of pollutants. A maximum batch adsorption capacity of 806.38 mg g-1 was achieved at optimal conditions. The Freundlich model best represented the equilibrium data, although the pseudo-second-order kinetic model best described the adsorption kinetics. The thermodynamic studies demonstrated that the adsorption process was spontaneous (ΔG° < 0) and endothermic (ΔH° = 32.512 kJ mol-1). DFT descriptors were combined with COSMO-RS and AIM theory to provide a complete picture of the adsorbate/adsorbent system and its molecular interactions. Last, the ACCFP was regenerable up to four times, emphasizing the idea of using it as an adsorbent to treat textile wastewaters.

The Role of an Aqueous Extract of Cactus on Histopancreatic Architecture in Streptozotocin Induced Diabetes Mellitus in Wistar Rats

Herbs have been used as medicinal for several years to cure or rather manage different ailments such as diabetes mellitus. This is very common in rural settings of sub-saharan Africa and is now being adopted in urban areas. Opunta species have widely been seen to contain antihyperglycaemic effects. To evaluate the antihyperglycaemic and histopancreatic effect of aqueous extract of prickly pear cactus (Opuntia species) cladodes in streptozotocin-induced diabetic male Wistar rats in vivo. This was a laboratory based research conducted at Mulungushi University involving 30 wistar rats (Rattus norvegicus) that weighed between 160-200 g which were randomly selected into five groups (6 per cage); normal control, diabetic control, diabetic +metformin, diabetic +cactus and cactus only group. Initial blood glucose levels were obtained from the tail and record then Diabetes mellitus was induced using a single intraperitoneal dose of streptozotocin (70mg/kg BW) and established a persistent state of hyperglycemia after 72hours. The aqueous cactus extract of 100 mg/kg BW and metformin of 100 mg/kg BW was administered orally using intragastric cannula daily for a period of 4 weeks. At the end of the fourth week, Diabetes + cactus and diabetes + metformin groups body weights were statistically significant when compared to the diabetic group (P&lt;0.05). While diabetic group was statistically significant when compared to normal control (P&lt;0.05). The relative weight of the pancreas in diabetic group was statistically significant to other groups (P&lt;0.05). The blood glucose in diabetic + cactus was normoglycaemic at 3rd week, Diabetic + metformin group when compared to diabetic group was statistically significant (P&lt;0.05). The normal control and cactus only groups maintained normoglycaemic till the end of the 4th week. The histological findings of the normal control and cactus only group showed normal pancreatic cytoarchitecture. Diabetes group showed high degree of disorganization in the cytoarchitecture in the islet with reduction in β cell mass and deposition of elastic fibres. The Diabetic+Metformin group showed slight decrease in the cell mass (β cells) and elastic fibres were extensively deposited. Diabetic+Cactus treated group exhibited normal histology of the pancreas with increased number of β cells. Opuntia species are able to lower elevated blood glucose levels and ameliorate the effects of STZ on the pancreatic morphology

Hiding in plain sight: Cryptic enemies are found on cochineal (Hemiptera: Dactylopiidae), a scale insect of economic and cultural significance.

Cochineal is the common name for cactus‐feeding scale insects in the Dactylopiidae. These ruby‐red insects include the domesticated dye insect Dactylopius coccus. Dactylopius coccus and congeners have been introduced around the world, some accidentally, to become pests of prickly pear cactus species (Opuntia), and some intentionally, for dye production or biological control of pest Opuntia. In the northern Sonoran Desert (Tucson, AZ, USA), we studied the enemy complex of D. opuntiae and D. confusus on Opuntia and characterized two cryptic enemies, a coccinellid beetle predator and a parasitoid wasp. (1) Hyperaspis sp. The coccinellid predator Hyperaspis trifurcata shares a niche with a similar, typically all‐black beetle. Morphological data, crossing tests, and phylogenetic results showed the black beetle to be a distinct, undescribed species in the genus Hyperaspis, with a rare spotted phenotype that is similar in appearance to H. trifurcata. Crossing tests among black and spotted forms showed the spotted morph is inherited as a single‐locus dominant allele. (2) Formicencyrtus thoreauini. Rearing of this ant‐like parasitoid wasp (Encyrtidae) in pure culture of D. opuntiae showed it to be a semi‐gregarious primary parasitoid of cochineal. To our knowledge, this is the first confirmed instance of a cochineal parasitoid. Observations of development show early instar larvae keep their posterior end within the egg chorion, attached to an aeroscopic plate with a connection to the cochineal body wall. Late instar larvae are eventually surrounded by a membrane, likely of larval origin. Wasps then pupate in a dry air‐filled chamber within the desiccated scale remains before chewing out as an adult. Both Hyperaspis sp. and F. thoreauini may have restricted distributions. Hyperaspis sp. does not appear to be a member of the cochineal community in Mexico or Texas, and scant records suggest F. thoreauini may also be restricted to the Southwestern USA.

Effects of fruit thinning and some fruit and cladode components on fruit growth and fruit weight of cactus pear Opuntia ficus-indica (L.) Mill

The aim of this paper is to study the effect of fruit thinning and some fruit and cladode components on fruit growth and weight of cactus pear Opuntia ficus-indica (L.) Mill. The relationships between the fruit fresh weight and each of the parameters number of fruits per cladode, surface of cladodes and the dry weight of cladodes are studied. Experiments were carried out on an adult plantation of cactus pear in the Agadir area. Fruit thinning treatments used were: T: control without thinning, T1: thinning treatment of 6 fruits per cladode and T2: thinning treatment of 12 fruits per cladode. The size of cladodes used are: the small cladodes (C1), the medium cladodes (C2) and the large cladodes (C3). Obtained results showed that fruit thinning and the surface of cladodes and the interaction of the two factors have a significant effect (p ≤ 0.001) on fruit growth. On May 10, 2019, the highest rate of growth was obtained with the combination T1/C3 (thinning treatment T1 and large cladodes C3), with 1.6 cm for fruit length and 1 cm for fruit diameter, and the lowest rate of growth was obtained with the combination C1/T (not thinned plants and small cladodes C1) with 0.5 cm for fruit length and 0.3 cm for fruit diameter. The ratio dry weight of cladodes/ number of fruits per cladode has a significant effect (p ≤ 0.001) on the fruit fresh weight. The increase in the dry weight of cladodes and the reduction in the number of fruits per cladode leads to the production of fruits with large size. Positive linear relationships exist between the fruit fresh weight and the ratio dry weight of cladodes/ number of fruits per cladode, between the fruit fresh weight and the number of fruits per cladode, and between the fruit fresh weight and the surface of cladodes and the coefficient of determination R2 for each linear relationship is close to 1.

On the origin of the two putative allopolyploids, Opuntia curvispina and O. martiniana (Cactaceae): A case of cryptic speciation in prickly pear cacti

The putative allopolyploid taxon, Opuntia curvispina, is distributed from northeastern Arizona and southern Nevada to southeastern California, where it often grows in close proximity to, or sympatric with, O. chlorotica, O. engelmannii and O. phaeacantha. Another putative allopolyploid, O. martiniana, grows sympatrically with O. curvispina in only one area north of the Hualapai Mts., northwestern Arizona. Both of these taxa have previously been treated as either nothospecies or mere spontaneous hybrids by previous researchers. My objectives were to determine the origins of both O. curvispina and O. martiniana to test previous hypotheses of hybrid origin, with O. curvispina putatively derived from O. chlorotica and O. phaeacantha and O. martiniana putatively derived from O. chlorotica and O. engelmannii. I also wanted to determine the overall extent of the ranges of the two taxa by expanding collections and verifying existing herbarium collections, as numerous specimens identified as O. martiniana and O. curvispina have been reported from outside of their expected ranges. My data indicate that O. curvispina indeed is partially derived from O. chlorotica, as well as another putative parent, likely O. phaeacantha, while O. martiniana appears to be most likely derived from O. curvispina and O. macrorhiza, two taxa not before implicated in the origin of O. martiniana. The hexaploid O. phaeacantha also appears to be non-monophyletic and may have been derived several times from different hybridization events. Careful morphological study of O. martiniana clearly separates that species from O. curvispina, although it may be considered cryptically different, a likely result of its partial putative origin from O. curvispina. Given the very broad distribution and dominance of O. curvispina in parts of its range, it is most appropriate to recognize this allopolyploid as a species, rather than as a nothotaxon, as previously designated. The unique feature of an obovate or urceolate style in Opuntia martiniana appears to be a transgressive trait rather than a synapomorphy, given that the taxon is derived from reticulation, and neither putative parent exhibits that character state. This work provides a framework for species recognition using DNA sequence data, morphological characters, geography and cytological information—a total evidence approach clearly needed for taxonomically difficult taxa, such as many within the genus Opuntia. A treatment of O. curvispina and O. martiniana is given with updated descriptions, and O. martiniana is neotypified.

Donald Pinkava's journey from Asteraceae to Cactaceae: from the Ohio State University to Arizona State University

Donald J. Pinkava is best known for his application of cytogenetics in unraveling the complex interspecific hybridization in the prickly pear genus Opuntia Mill. in the southwestern United States extending down into northern and central Mexico. Using cytogenetics, Pinkava delimited species boundaries within Opuntia for taxonomic treatments. His work on Opuntia in the Chihuahuan Desert led to later comprehensive contributions in the Flora of North America and the Flora of Arizona that include opuntias not only in the Southwest but in every US state. Pinkava's systematic knowledge, as reflected in his taxonomic treatments provided the basic scientific framework needed for ongoing conservation of Cactaceae in the Southwest to the present day. Interestingly, the starting point for all of Pinkava's contributions in Cactaceae began with his initial studies of Asteraceae as a student of T. Richard Fisher at The Ohio State University (OSU), an institution with longstanding research interests in the Asteraceae. It is there that he selected a genus, Berlandiera DC as his dissertation topic. Ironically, this genus has a range from the drier sites of the Eastern Coastal Plains, into the Ozark and Ouachita Mountains, with a disjunct distribution in the mountain floras of southeastern Arizona and Northern Mexico. Like Berlandiera, Pinkava’s own work reflects techniques and training in the eastern US, that migrated and was used as the basis for his groundbreaking studies of Cactaceae in the Southwest.

Typology of dairy goat production systems in a semiarid region of Brazil

Socio-productive initiatives that culminated with the advent of the Food Acquisition Program in the Milk modality (PAA Milk) in 2003 boosted the development of Local Productive Arrangements for the dairy goat farming, especially in the area located between the states of Paraíba and Pernambuco, belonging to the Northeast region of Brazil. Considerable changes were performed in goat production systems with the introduction of specialized breeds, new facilities, and increased consumption of external inputs, especially concentrate feed, among other changes. This study characterized the socioeconomic, productive, and structural diversity of dairy goat production systems on 334 farms in the state of Paraíba and 220 farms in the state of Pernambuco aiming to understand the current situation of the production systems and to bring reflections on possible actions for improvement. Multiple correspondence and hierarchical cluster analyses were performed in sequence to establish the typology. Qualitative and quantitative variables were analyzed in the multiple correspondence analysis, and then the first three dimensions (coordinates) were retained for the cluster analysis, which generated three groups of farms: Group I with 216 farms (39% of the sample), Group II with 127 farms (22.9% of the sample), and Group III with 211 farms (38.1% of the sample). Group I had a lower percentage of landowners (34%), a lower presence of retired producers, lower frequencies of cactus pear areas and annual planting for forage conservation, low livestock diversity, few water facilities, and high access to PAA Milk ( 92%). In Group II, 80% of producers own their farms, have the smallest goat herd (18 heads), high presence of cactus pear areas and annual planting, and, consequently, a high practice of forage conservation and diversity of water facilities. Group III presented the oldest producers, larger areas of properties (41 ha), high presence of native pasture area, and higher daily milk production per farm (21 L). The results showed diversity among the identified groups, but with important similar aspects, such as the introduction of specialized breeds for milk production, the fragility of the feed security of herds, high stocking rates of ruminants, and a strong dependence on external feeds compared to those produced in the systems, particularly concentrate feeds, in addition to the high dependence on PAA Milk for production distribution and production stagnation due to few commercialization alternatives. It is necessary to implement solutions for the main identified distortions, such as improvement in the use of native and cultivated forages, adequacy of the stocking rate, reassessment of the composition strategy of the goat herd with specialized animals, and, mainly, the search for new dairy products and marketing channels to reduce the dependence on PAA Milk.

Pharmacology of α-spinasterol, a phytosterol with nutraceutical values: A review.

α-Spinasterol is a phytosterol found in various edible and non-edible plant sources. The edible plant materials containing α-spinasterol include spinach leaves, cucumber fruits, seeds of pumpkin and watermelon, argan seed oil, cactus pear seed oil and Amaranthus sp. It is a bioavailable nutraceutical, and it can cross the blood-brain barrier. It possesses several important pharmacological properties such as anti-diabetes mellitus, antiinflammation, hypolipidemic, antiulcer, neuroprotection, anti-pain and antitumour activities. For this review, literature search was made focusing on the pharmacological properties of α-spinasterol using PubMed and Google Scholar data bases. Recent studies show the promising antidiabetic properties of α-spinasterol. Its anti-diabetic mechanisms include enhancement of insulin secretion, reduction in insulin resistance, anti-diabetic nephropathy, increase in glucose uptake in muscle cells and inhibition of glucose absorption from intestine. Besides, it is a safe antiinflammatory agent, and its antiinflammatory mechanisms include inhibition of cyclooxygenases, antagonism of TRPV1 receptor and attenuation of proinflammatory cytokines and mediators. It is a promising and safe nutraceutical molecule for human health care. Food supplements, value-added products and nutraceutical formulations can be developed with α-spinasterol for the management of diabetes, chronic inflammatory diseases and improving general health. This review provides all scattered pharmacological studies on α-spinasterol in one place and highlights its immense value for human health care.

Effect of endomycorrhiza (Glomus intrarradices) and organic matter on the growth of cactus pear (Opuntia albicarpa) in two soil types

Most of the farmers who grow cactus pear (Opuntia albicarpa) use manure as a fertilizer. This practice increases the problems of pests. The use of endomycorrhiza (Glomus intraradices) is almost unknown to farmers. Therefore, the objective of this research was to study the effect of the application with organic matter (OM) and inoculation with endomycorrhiza in cactus pear.&#x0D; The study was conducted under greenhouse conditions at the Montecillo Campus of the Postgraduate College, Mexico. Two types of soil from San Luis Potosí, Mexico were used, one of reddish coloration (xerosol) and another gray (lithosol).&#x0D; The results show that there were significant differences (p ≤ 0.05) in all the variables by the inoculation with endomycorrhiza, and in the majority of those by the application of OM. Both the mycorrhiza and the application of OM, as vermicompost, promoted a greater growth of the stem and the root. The types of soils used did not affect the growth of the plants.&#x0D; The mycorrhiza can be useful to improve mineral nutrition, and thus increase yields in the cactus pear plantations. In addition, these fungi can increase yields, and help reduce production costs. The application of 50 t ha-1 of vermicompost is a better alternative to add nutrients and OM to this crop.

The economic potentialities of cactus pear as food and forage crop for sustainable agriculture in the arid and semi-arid regions: A review

The adaptation of cactus pear to arid environments and its importance in animal and human feed make the species largely used in the arid and semi-arid regions. The economic potentialities of cactus pear as food and forage crop and its production in animal and human feed are higher. Cactus pear products and by-products and the production sustainability of cactus pear in the arid and semi-arid areas open a great number of opportunities and hopes to rural populations of these regions. These products and by-products constitute a source of income for low income of rural populations. The nutritional value of cactus pear products and their content in minerals and vitamins make cactus pear fruits and cladodes important in the animal and human feed in the arid and semi-arid areas. Medicinal and cosmetic by-products are also obtained from cactus pear products. They increase the economic income of the farmers and rural populations. Cactus pear is also an important forage for livestock in the arid and semi-arid regions thanks to its high biomass production and palatability. Cactus pear pads are consumed by all the types of livestock. They are rich in water and carbohydrates and their digestibility is high, but their content in crude proteins is low. Cactus pear could be a supplement for low quality fodder such as straw, and the combination of the two elements could be an alternative fodder for the animals of the arid and semi-arid regions.

Chemical Composition of Cactus Pear Seed Oil: phenolics identification and antioxidant activity.

ObjectivesThe chemical composition of cactus pear seed oil (Opuntia ficus-indica [L.] Mill.) was analyzed in terms of its fatty acid composition, tocopherol content, phenolic identification, and the oil’s phenolic-rich fraction antioxidant power was determined.MethodsFatty acid profiling was performed by gas chromatography coupled to an FI detector. Tocopherols and phenolic compounds were analyzed by LC-FLD/UV, and the oil’s phenolic-rich fraction antioxidant power was determined by phosphomolybdenum, DPPH assay and β-carotene bleaching test.ResultsFatty acid composition was marked by a high unsaturation level (83.22 ± 0.34%). The predominant fatty acid was linoleic acid (66.79 ± 0.78%), followed by oleic acid (15.16 ± 0.42%) and palmitic acid (12.70 ± 0.03%). The main tocopherol was γ-tocopherol (172.59 ± 7.59 mg/kg. In addition, Tyrosol, vanillic acid, vanillin, ferulic acid, pinoresinol, and cinnamic acid were identified as phenolic compounds in the analyzed seed oil. Moreover, the oil’s phenolics-rich fraction showed a significant total antioxidant activity, scavenged DPPH up to 97.85%, and effectively protected β-carotene against bleaching (97.56%).ConclusionThe results support the potential use of cactus pear seed oil as a functional food.

Effect of fruit thinning on fruit yield and quality of cactus pear Opuntia ficus-indica (L.) Mill. in a semi-arid area

The aim of this work was to study the effect of fruit thinning on fruit yield and quality of cactus pear. To meet this objective, trials on fruit thinning were conducted on an adult plantation of cactus pear in a semi-arid region in southern Morocco. The fruit thinning consisted of reducing the fruit load of overcharged cladodes by reducing the number of fruits to 6 or 12 per cladode. It was practiced in early May on three types of one-year old cladodes (small cladodes, the medium ones and large cladodes), by removing some floral buds or young fruits at the flowering stage. The control cladodes had an average number of 18 fruits per cladode. Obtained results showed that the reduction in the load of cladodes improved fruit size and quality. In thinned plants to 6 fruits per cladode and for the three types of cladodes, average fruit weight was 160.44 g and average fruit length and diameter was 8.64 and 6.38 cm respectively. While in not thinned plants and for the three types of cladodes, average fruit weight was only 74.53 g and average fruit length and diameter was 6.40 and 4.46 cm respectively. Fruit thinning increased the content of sugar in the fruits and decreased the number of seeds in the fruits and the fruit peel thickness, but did not affect the juice content in the fruits and the pH and titratable acidity of the juice. Fruit thinning also improved the economic income of the yield and the gain in the yield of thinned plants to 6 fruits per cladode was 33912 DH per hectare compared to not thinned plants.

Physiological quality of forage palm seeds and seedlings associated with the level of ploidy

The forage palm is widely cultivated in semiarid regions. It has a basic chromosome number of x = 11 and polyploids are the main variation. It is propagated via vegetative reproduction, and sexual propagation is rarely used. The objective was to associate the physiological quality of seeds of different cultivars of forage palm with the level of ploidy in the genera Opuntia and Nopalea. The cultivars used were: diploids (2n = 22) ‘F8’, ‘F21’, and ‘IPA Sertânia’; tetraploids (2n = 44) ‘Clone 6 African Elephant Ear’, ‘Mexican Elephant Ear’, and ‘V19’, and octaploids (2n = 88) ‘Round’, ‘Giant’, and ‘IPA Clone 20’. Thousand seed weight, length, diameter, number of seeds per fruit, first count and emergence percentage, shoot and root length, fresh and dry mass, electrical conductivity, and length, width, and fresh and dry weight of cladodes were measured. A nested scheme design was used, with three levels of ploidy and three cultivars within each level. The ploidy level positively influenced the number of seeds per fruit and the physiological quality of the seeds. Cultivars behave differently within the same ploidy level.

DISTRIBUIÇÃO RADICULAR, TEOR E EXPORTAÇÃO DE NUTRIENTES EM PALMA FORRAGEIRA ‘GIGANTE’ IRRIGADA COM ÁGUA SALOBRA

ABSTRACT In semiarid regions with greater climatic variability, including prolonged droughts and delayed rainy seasons, supplemental irrigation is critical to ensuring yields of forage cactus pear. The objective was to evaluate root distribution and nutrient concentration and accumulation in ‘Gigante’ forage cactus pear subjected to different irrigation regimes. Seven irrigation regimes were tested: no irrigation (rainfed); five liters of medium-salinity water, with an electrical conductivity (EC) of 0.75 dS m−1, applied per linear meter every 15 days; 7% reference evapotranspiration (ETo) with a 15-d irrigation interval (II); 15% ETo with a 7-d II; 33% ETo with a 3-d II; 50% ETo with a 2-d II; and 100% ETo, irrigated daily - high-salinity water, EC of 3.6 dS m−1, was used in the last five treatments. The treatments were laid out in a randomized block design with four replicates. Roots developed best in plants irrigated at 50% ETo with a 7-d II. Applying high-salinity water at 15% ETo with a 7-d irrigation interval promotes higher concentrations of P, Ca, Mg and S in cladodes of cactus pear. Applying high-salinity water at 33% ETo with a 3-d II promotes higher uptake/accumulation of P, Ca, Mg, S and Zn in cladodes of ‘Gigante’ forage cactus pear.