Dactylopius opuntiae is a pest that threatens cactus pear cultivation worldwide. In Morocco, thousands of hectares have been completely destroyed since its introduction in 2014. The use of resistant ecotypes remains the most effective strategy to safeguard cactus cultivation at the national scale. The objective of the present study was to evaluate, under greenhouse conditions over a 45-day period, the resistance of 11 cactus pear ecotypes, as well as to perform pomological and phenological characterization of these clones. The results showed a very high level of resistance in ecotype 54, with 0% infestation by adult females. This ecotype prevented the development of cactus cochineal larvae into the adult stage, whereas the other ecotypes allowed the establishment of adult female colonies with infestation rates not exceeding 25%. In contrast, ecotype 149 was found to be highly susceptible. Analysis of colonization dynamics using an exponential growth model confirmed these results. However, clones 10, 11, 14, 19, 27, 28, and 34 exhibited rapid population growth of D. opuntiae, with multiplication factors close to those observed in ecotype 149 and the susceptible control. Pomological characterization revealed that clone 54 exhibited low pomological performance, whereas the ten other tested clones showed medium to high pomological profiles. Phenological monitoring indicated that clones 14, 18, 27, 28, 29, 34, 54 and 149 were characterized by fruit maturity occurring from late July to mid-August. In contrast, clones 10 and 11 were late-maturing, with fruit maturity beginning in mid-September.
Pitaya (Stenocereus sp.) is recognized for its high antioxidant potential and abundance of bioactive compounds. The aim of this study was to evaluate the effects of supplementing pitaya must with different carbon sources on fermentation performance, physicochemical characteristics, and antioxidant capacity to identify the most suitable formulation for pitaya wine production. Pitaya juices were adjusted to 22 degrees Brix and fermented with Saccharomyces cerevisiae at 27 degrees C for 9 days. Fermentation was assessed by soluble solids (degrees Brix), total reducing sugars (TRS), ethanol production, fermentation yield, and fermentation efficiency. The final beverages were characterized by color, total phenolic content, betalains, and antioxidant capacity using DPPH, ABTS, and FRAP assays. Significant differences (p < 0.05) were observed among carbon sources. All treatments showed a marked decline in degrees Brix during the first 3-5 days. Pitaya supplemented with agave syrup (AASP) exhibited the highest fermentative performance, reaching the highest ethanol concentration (84.16 g L-1), fermentation yield (0.46 g ethanol/g sugar consumed), and fermentation efficiency (89.71%). The FRAP and ABTS assays showed that AASP after fermentation exhibited the highest antioxidant capacity, with values of 640.90 +/- 2.57 and 11,568.33 +/- 147.99 mu mol TE mL(-1), respectively, whereas the greatest DPPH scavenging activity was observed in agave syrup after fermentation (AAS) (632.11 +/- 12.62 mu mol TE mL(-1)). The highest total phenolic content was observed in agave syrup with pitaya before fermentation (BASP), with a value of 404.94 +/- 1.85 mg GAE L-1. These findings demonstrate that agave syrup is the most suitable carbon source for producing fermented pitaya beverages with high fermentative efficiency while preserving their antioxidant potential.
The peels of Opuntia fruits are usually discarded as agri-food waste, yet they are a rich source of dietary fiber and bioactive compounds with potential functional applications. This study compared the phytochemical composition and antioxidant properties of the peels from six Opuntia species native to Hidalgo, Mexico; O. albicarpa, O. megacantha, O. ficus-indica, O. xoconostle, O. robusta, and O. undulata as a function of species identity and extraction solvent (aqueous vs. ethanolic). We hypothesized that interspecific variability in peel chemistry, combined with solvent polarity effects, would produce significant differences in all measured variables. Total, insoluble, and soluble dietary fiber in freeze-dried peel powder were determined. Aqueous and ethanolic extracts were evaluated for radical scavenging DPPH (2,2-diphenyl-1-picrylhydrazyl), antioxidant capacity ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)), beta-carotene oxidative discoloration inhibition, total polyphenols (Folin-Ciocalteu), and total flavonoids. O. robusta showed the highest total dietary fiber (60.22% d.b.), followed by O. ficus-indica (55.73% d.b.). Aqueous extracts of O. megacantha and O. undulata showed the highest DPPH radical scavenging activity (21.38 and 23.99% FRS, respectively), statistically comparable to the BHT control. ABTS antioxidant capacity was highest in aqueous extracts of O. ficus-indica and O. robusta (91.07 and 90.98 mu mol TE/100 g d.b., respectively). Aqueous extracts consistently outperformed ethanolic extracts in polyphenol recovery, while ethanolic extracts showed higher flavonoid content in most species. The species & times; solvent interaction was significant for all bioactivity variables (p < 0.05). These results indicate that Opuntia peels from these six Mexican species are a viable source of dietary fiber and bioactive compounds, supporting their use as functional food ingredients and nutraceutical raw materials.
Possible effects of climate change, affecting rainfall patterns and longer dry spells make it necessary to research climate resilient forage alternatives for livestock feeding towards sustainable intensification, with good quality forages adapted to varied environments and hydric cycles. Forage Opuntia cactus may be a main component of diets for ruminants given its nutritional quality; and conserving Opuntia cactus as silage addresses the need to have forage year-round. Additives may enhance fermentation characteristics or the nutritional value of silage. There is a knowledge gap in the specialized literature on the effect of additives on the nutritional value of Opuntia silages. Therefore, the objective was to evaluate in laboratory microsilos the effect of adding a bacterial inoculant as source of homofermentative bacteria, or urea as a source of non-protein nitrogen, or the inclusion of both additives in the chemical composition and in vitro nutritive value of Opuntia silages. The treatments were: Control (TxC)= 70% forage Opuntia with 20% ground maize stover with ears and 10% sugarcane molasses; TxI= Control plus bacteria inoculum; TxU= Control plus 0.5% urea; and TxI/U= Control plus inoculum and urea. There were five microsilos per treatment in 4 L plastic buckets with lids that were opened after 28 days. Chemical composition of silages was determined in terms of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), and in vitro digestibility of dry matter (IVDMD). Number and size of mold colonies, temperature and pH of silages were also determined. Treatments with urea (TxU and TxI/U) increased CP content (P<0.05) and IVDMD. There were no differences for number or size of mold colonies (P>0.05), but treatments with bacterial inoculum (TxI and TxI/U) showed lower pH (P<0.05). Results are valid, since experimental silos may have a more active fermentation compared to farm silos, microsilos are useful because results are like farm silos. In this experiment, results showed that Opuntia silages may be a forage option, and the addition of bacterial inoculum improved fermentation, and the addition of urea increased the CP content, that by also increasing IVDMD, may meet requirements for maintenance and moderate growth in cattle. It is concluded that Opuntia silages with 20% ground maize stover with ears and 10% of molasses (fresh basis) are a viable forage alternative for feeding ruminants, and the addition of bacterial inoculum and urea improves fermentation conditions and increases crude protein content.
Mexico is the world’s leading producer and consumer of Opuntia ficus-indica. However, production of this crop is constantly affected by the wild cochineal (Dactylopius opuntiae Cockerell), which is the most economically important pest of prickly pear. The objective of this study was to evaluate the biological effectiveness of several biorational insecticides for controlling wild cochineal populations on nopal cactus and to reduce the use of conventional pesticides. The study was conducted in a seven-year-old commercial nopal plantation located in Tlalnepantla, Morelos, Mexico. Seven biorational insecticides each applied at two doses (low and high) were evaluated: Cinnacar®, Blinem®, Asphix®, Mass derrive, Prowet Ovi-Die®, Roma® soap + Bemix®, and potassium soap, in addition to a regional conventional control based on Malathion 1000 CE at two doses (low and high). The experimental design was a completely randomized design with four replicates per treatment. Applications were performed using a motorized sprayer. Results showed that potassium soap achieved >50% control in third-level cladodes and up to 49.2% on the fourth-level cladodes, even under high infestation pressure. Likewise, some products such as Roma soap, Prowet Ovi-Die, and Mass derrive may be effective against initial infestations of less than 30%, depending on the structural area of application. Furthermore, since female nymphs tend to migrate vertically to areas with lower cellulose content within the plant structure to insert their mouthparts and establish their sessile stage, it is important to maintain control of the mealybug on the third level; otherwise, the cladodes on the fourth level will also be affected. These results indicate that biorational insecticides are a viable and environmentally safe component of integrated pest management strategies for controlling wild cochineal in open-field production systems for nopal as a vegetable crop.
