Journal of the Professional Association for Cactus Development

Agronanotechnology in the arid zones of northern Mexico: Research, challenges, and new trends

Mónica Anzaldo-Montoya — 2024-01-19

The agri-food systems in arid zones face challenges related to climate change, desertification, and soil contamination from agrochemicals' actions, among others. The agronanotechnology can generate alternatives to these problems, but it is necessary to monitor its development to have elements to apply policies that are oriented to the attention of these regions with a social perspective. This scientific paper aims to present provide a study of the situation of agronanotechnology in the arid zones of northern Mexico. Using bibliometric tools, the academic output in the field and map the public research agenda, focusing on providing the set of crops to which the local research is directed was analyzed. Furthermore, the literature associated with the risks to human health and the environment derived from some nanomaterials of agri-food interest and clarify the areas of opportunity and trends was reviewed. The results show a total of 224 research articles authored by 1029 scholars in 161 journals published from 2004 to 2022; that research on this topic reached its highest value in 2018 and then levels off at a value around of ~37%. The findings show a research agenda related to crops of economic interest for the export market like tequila, tomato, avocado, chili, watermelon. In México, agronanotechnology is an emerging field that deals with some crops of economic interest, but its development needs to be intertwined with the needs of rural producers.

Optimization of DNA Extraction for ITS/U4U3 analysis of Rhipsalis baccifera

Tomás Rivas-García — 2024-07-03

Genetic analysis of plants relies on high yields of pure DNA. For Rhipsalis baccifera this represents a great challenge since its plant tissue can accumulate large amounts of mucilage, polysaccharides, polyphenols and secondary metabolites, which co-purify with amplifiable DNA. These contaminating compounds lead to a poor yield and prevent acces to PCR-based analysis. These contaminating compounds lead to a poor DNA yield and prevent access to PCR-based analysis. A number of factors, including choice of plant tissue, tissue preparation, and modifications of the extraction buffer, can impact on DNA extraction process. In this study, four different DNA extraction procedures were tested aiming to develop a simple protocol based on CTAB buffer. The obtained results showed that the use of the outer cuticle of old lyophilized tissue allowed reliable results in R. baccifera plants with a good purity ranging from 1.6 to 1.8 and high DNA yield yield ? 500 ng ?L^-1.

Seed morphometry and NaCl and sucrose effect on germination rates and phytochemicals in sotol (Dasylirion acrotrichum) from the Chihuahua state, Mexico

José Valero Galvan — 2024-05-20

In Mexico, “sotoles” (Dasylirion spp.) are used to elaborate the “sotol” liquor, handicraft making, and construction materials. These activities have enhanced the probability that sotol populations could decline because plants are extracted directly from their native ecosystems, given no commercial sotol plant species exist. Furthermore, from an ecological point of view, this genus has also been little studied regarding its seed morphology and germination process. The objective of this study was to characterize the morphometry of the D. acrotrichum seeds and to evaluate the effect of different concentrations of NaCl (30, 60, and 90 mM) and sucrose (30, 60, and 90 mM) on seed germination rates, seedling morphology, and the phytochemical content in the seedling leaves under in vitro conditions from plants grown in the Chihuahua State. The exogenous NaCl and sucrose treatments influenced the germination speed index, mean germination time, and mean germination speed. The NaCl treatment impacted the total weight, root weight, and leaf length of seedlings, the content of chlorophyll a, sugar, and phenolics, and the antioxidant activity determined by FRAP. Besides, the sucrose treatment affected the seedling length, the content of chlorophyll a, chlorophyll b, total chlorophyll, and sugars, and the antioxidant activity determined by FRAP and DPPH. These results could provide the guidelines to generate better afforestation programs in the areas affected by the overexploitation of the Dasylirion spp. and new information about the capacity of these species for developing under these types of stress in the natural environment.

Potential causal factors of “heart-shaped cladode” malformations in cactus pear (Opuntia ficus-indica (L.) Miller)

Maria Eddy Mendoza-Orozco — 2024-04-29

The prevalence and severity of pests and diseases are factors that limit productivity and quality in commercial cactus pear plantations in Mexico. Recently, in several cactus pear producing regions the appearance of diverse symptoms associated with “heart-shaped cladodes” has been registered. This disease is characterized by the loss of apical dominance of vegetative shoots leading to abnormal cladode growth. Besides the aesthetic damage, vegetative and floral buds disappear in the zone of invagination, thus reducing productivity. Because to date the causal agent is unknown, this study was conducted to analyze three possible agents, damage by insects, physical damage and phytoplasmas that could possibly cause the symptomatology of “heart-shaped cladode”, aiming to constitute a base line for future studies. The study was conducted under semi-controlled conditions and in the field, using Opuntia ficus-indica cv. Villanueva plants and cladodes. To rule out causal agents that occur naturally in cactus pear productive systems, the following characteristics were analyzed: detected presence of Diabrotica undecimpunctata, simulation of physical damage by puncturing 4- and 13-day-old shoots with a needle, and detection of phytoplasmas with PCR and RFLP. The results of the study showed that, although it feeds on shoots, D. undecimpunctata does not cause the symptoms. The puncture with a needle on the apical part promoted the presence of symptoms. The PCR and RFLP analyses detected the presence of phytoplasmas on both symptomatic and asymptomatic shoots. For this reason, it was not possible to conclude that phytoplasmas are the causal agents of heart-shaped cladode.

Floral morpho-anatomy and reproductive biology of Mammillaria lasiacantha Engelm. (Cactaceae) at Sierra of Juárez, Chihuahua

Coyolxauhqui Figueroa — 2024-04-16

Mammillaria lasiacantha is a small cactus that inhabits at Sierra of Juárez, Chihuahua, Mexico. Their populations have been affected by habitat destruction, illegal extraction, and uncontrolled tourism in the region that steps on the seedlings; therefore, knowing its reproductive biology is necessary for its conservation. Our main questions were: What is the floral morphology and anatomy like? What type of sexual and mating system do M. lasiacantha present? Do the seeds produced by the crosses germinate, how and in what percentage? Sixty individuals from a population of 120 plants were studied at Sierra of Juárez, Juárez Chihuahua from January to August 2021. The study of the floral morpho-anatomy was carried out. Four treatments were applied: natural selfing, forced selfing, geitonogamy and forced outcrossing plus a control. Pollinated flowers, fruits, number of seeds and germination percentage were recorded. Flowers have naked pericarp, funnel-type nectary, nectarostomata, closed style and collateral vascular bundles. The anatomical characteristics of M. lasiacantha agree with those reported for other species of Mammillaria. The flowers of M. lasiacantha present herkogamy, with an obligate outcrossing system. The seeds produced from the outcrossing and control group germinated in 32 and 76%, respectively. The herkogamy and strict outcrossing system of M. lasiacantha should be confirmed in other populations. The seeds are positive photoblastic, without dormancy, but the study of the seed bank and seedling survival in the field would be pertinent. The ex-situ conservation of M. lasiacantha in the site will be feasible, since species high percentage of germination may contribute to produce plants for restoration programs.

Formation of calcium oxalates and carbonates due to water stress in “nopalitos”

Rafael Zuñiga-Valenzuela — 2023-04-08

The “nopalitos” (Opuntia ficus-indica L. Miller) is an essential source of calcium in the human diet; however, the bioavailability and viability of the mineral are limited by precipitating in the form of calcium oxalate (CaC₂O₄) when the plant is exposed to water stress. The objective of this study was to quantify calcium oxalates and carbonates in cactus subjected to water differentials of 10, 30 and 60% of available water (AW) through photomicrographic analysis. The micro mosaics are composed of sequential images of a 10x amplitude, taken in a petrographic microscope with different light sources, plane-polarized light (LPP), cross-polarized light (LPC), and light compensated (LPC). High spectral resolution mosaics were produced using geospatial operators (ArcGIS v.10.1 and ERDAS Imagine, 2014v®). The CaC₂O₄ and CaCO₃ were identified by spectral signature or brightness degrees in RGB format images, quantifying the minerals and surface they occupy in the cladode. The quantification of minerals in situ in nopal cladodes at different water stresses showed significant differences (p<0.05) in the area occupied by oxalates at 10% water stress and calcium carbonates at 60% within the vegetal structures of nopal vegetables. Consequently, using high-resolution mosaics and spatial operators allows the identification and quantification of mineral biomarkers in plant tissues in situ. Therefore, using image overlay, the proposed method is an alternative to the in situ quantification of minerals in plant tissues.

Effect of using hydrogel polymers on morphometric, forage production, and nutritional characteristics of cactus pear

Pablo Ramon Costa — 2024-02-23

The use of cactus pear has shown poor performance in some areas of semi-arid climate regions, as the species needs a wide gradient between temperatures during the day and night to develop, which does not occur in such zones. To lessen this negative occurrence, moisture availability provides better performance for the species, such as using hydrogel instead of irrigation. The objective of this study was to evaluate the effect of using hydrogel polymers on the production of cactus pear (Opuntia stricta cv. Mexican Elephant Ear). Three treatments with six replications were used, totalling 18 experimental units. The treatments were, (1) Conventional fertilization using fertilizer in granulated format; (2) Foliar fertilization with polymer using a dilution dose of 6 grams of polymer L^-1of water associated with the fertilizer in liquid form through the foliar route; (3) Foliar fertilization without polymer using only foliar fertilization in the same formulation as the treatment with polymer. There was no effect of fertilization strategy on plant height, cladode length, cladode width, cladode thickness, cladode area, and biomass. There was an effect of the fertilization strategy on dry matter, in which higher estimates were measured for conventional fertilization and foliar fertilization without polymer. On the other hand, foliar fertilization with polymer promoted increases of 13% in mineral matter and 42% in crude protein in relation to conventional fertilization. The fertilization strategy did not change the other chemical attributes of cactus pear. The use of the hydrogel did not influence the morphometric development of the Mexican Elephant Ear cultivar but promoted increments in the chemical composition.