Morphological and antioxidant responses of Nopalea cochenillifera cv. Maya (edible Opuntia sp. “Kasugai Saboten”) to chilling acclimatization

Abstract

To clarify the wintering ability of the cactus Nopalea cochenillifera cv. Maya (edible Opuntia sp., common name “Kasugai Saboten”), we investigated the effects of temperature and antioxidant capacity on chilling acclimatization. We analyzed the anatomy of cladode chlorenchyma tissue of plants exposed to light under chilling. We found that chilling acclimatization can be achieved by exposure to approximately 15 °C for 2 weeks and suggest that it is affected by whether or not antioxidant capacity can recover. The overwintering cacti had the thinnest cuticle but firm cuticular wax, which is important in the acquisition of low temperature tolerance under strong light. In cacti with severe chilling injury, round swollen nuclei with clumping chloroplasts were localized in the upper part (axial side) of the cell, as though pushed up by large vacuoles in the lower part. In overwintering cacti, chloroplasts were arranged on the lateral side of the cell as in control plants, but they formed pockets: invaginations with a thin layer of chloroplast stroma that surrounded mitochondria and peroxisomes. Specific cellular structural changes depended on the degree of chilling stress and provide useful insights linking chloroplast behavior and structural changes to the environmental stress response.

Genomic insights into the clonal reproductive Opuntia cochenillifera: mitochondrial and chloroplast genomes of the cochineal cactus for enhanced understanding of structural dynamics and evolutionary implications

“…The cochineal cactus ( Opuntia cochenillifera (L.) Mill., Cactaceae), a succulent tree or shrub indigenous to Mexico, thrives primarily in desert or dry shrubland biomes. This species has gained global cultivation due to its extensive use in food, fodder, and medicinal applications for centuries ( Russell and Felker, 1987 ; Anaya-Pérez, 2001 ; Lans, 2006 ; Barba et al., 2017 ; Kondo et al., 2023 ; Prisa, 2023 ). Notably, O. cochenillifera has been historically important as a host plant for the cochineal insect ( Dactylopius coccus ), a source of the red cochineal or carmine dye, extensively utilized as a natural colorant in food and cosmetics ( Barba et al., 2017 ; Ramadan et al., 2021 ).…”