ALCATRAZ: CHARACTERISTICS, TAXONOMY, HABITAT, REPRODUCTION - BIOLOGY - 2025

The gannet (Zantedeschia aethiopica), also called calla or water lily, is a perennial plant belonging to the Araceae family. It is a herbaceous grown as an ornamental for the decorative brightly colored spathe that surrounds a spadix of yellow tones.

The calla lily flower is a group of inflorescences that grow along a spadix surrounded by modified bracts in a flared shape. The yellow inflorescences give off a pleasant fragrance, and the spathes are white, yellow, red, pink or mottled.

Zantedeschia aethiopica. Source: pixabay.com

The foliar area of ​​Zantedeschia aethiopica reaches an average height of 80-100 cm, and is characterized by the underground stem or rhizome. Bright green wavy basal leaves with pronounced veins and long petioles emerge from the rhizomatous stem.

In the commercial field, flowers are highly appreciated for their beauty and long life after cutting (8-10 days). They are frequently used in the elaboration of bouquets, bouquets and flower arrangements, being a flower that is distinguished by its beauty and sophistication.

The agricultural exploitation of this species is frequently carried out outdoors or under greenhouses, commercially white cultivars predominate. However, the demand for new varieties has increased the production of hybrids with a great variety of shades.

General characteristics

Herbaceous perennial plant, highly appreciated as an ornamental crop due to the particular shape of the inflorescence. This species reproduces by seeds or vegetatively through rhizomes.

Stem and root

The alcatraz plant is characterized by presenting an underground stem or rhizome 12-18 cm long. It fulfills the function of storing energy reserves, it also has vegetative buds in the upper end and roots in the lower end.

The roots of the fasciculate type are very numerous, thin and elongated, they are born from the base of the rhizome. The rhizomatous root constitutes the vegetative part that allows the asexual propagation of the plant.

Leaves

The numerous and erect leaves grow directly from the rhizome reaching a length of 60-120 cm. They are frequently lanceolate, oval, sagittate, or heart-shaped, have wavy edges, are bright green and in some cases marbled.

Flowers and fruits

The calla lily flower is located inside a funnel formed by modified leaves or bracts called spathes. This structure is bell-shaped wide towards the edges with the tip folded at one end.

Spathes are light, pink, yellow, red, or orange, and their primary function is to protect the reproductive organs. The flower itself is a lance-shaped inflorescence called a spadix.

Inflorescences and spathe of Zantedeschia aethiopica. Source: pixabay.com

The solitary inflorescence reaches 5-8 cm in length, and is located within the flared spathe on a long peduncle. It is a monoecious species, the male flowers are located in the upper part of the spadix and the female ones in the lower part.

The fruit is an oval or ellipsoid berry (5-10 mm) of yellowish color, each berry contains several globular seeds (3 mm). From each inflorescence 40-50 berries are produced that allow the sexual reproduction of the plant.

Taxonomy

- Kingdom: Plantae

- Subkingdom: Tracheobionta (vascular plants)

- Super division: Spermatophyta (plants with seeds)

- Phylum: Magnoliophyta (flowering plants)

- Class: Liliopsida (monocotyledonous angiosperms)

- Subclass: Arecidae

- Order: Arales

- Family: Araceae

- Genus: Zantedeschia

- Species: Zantedeschia aethiopica (L.) Spreng., 1826.

The Zantedeschia aethiopica species receives several common names: gannet, creek, Ethiopian creek, Ethiopian ring, water lily, or cartridge. Also known as duck flower or jug ​​flower, it is a perennial herbaceous plant native to South Africa.

It is a plant belonging to the araceae family, arales order, liliopsida class of the magnoliophyta division. The name Zantedeschia derives from the surname of the physician, physicist and botanist Francesco Zantedeschia (1798-1873), who described the flower in mid-1985.

Taxonomically, the Zantedeschia genus was initially reviewed by Sprengel (1926), successively revised by Engler (1915), Traub (1948), Letty (1973) and Perry (1989). In relation to the name aethiopica, it suggests the region of origin of the species, specifically south of the African continent.

Distribution and habitat

Zantedeschia aethiopica is a species native to southern Africa, specifically the Cape region in South Africa. It is a plant adapted to the subtropical and temperate climate, which is why it is cultivated in America, Europe, Australia and New Zealand.

This plant grows in wetlands, irrigation canals and drains, stream environments, swamps, and flooded lands. Likewise, it prefers shady and cool areas in order to avoid dehydration and wilting of the leaves.

Reproduction

This species is propagated sexually by seeds and vegetatively through the underground stem or rhizome. In the commercial field, the production of alcatraz is carried out by direct sowing, division of rhizomes, stripping of rhizomes or cultivation of cuttings.

Alcatraz cultivation. Source: Manfred Heyde creativecommons.org

Direct sowing

It is made from fertile seeds obtained from the best productive plants. Sowing is established in early spring, observing the presence of incipient rhizomes in mid-autumn.

Zantedeschia is a perennial plant, so it takes two years to obtain productive rhizomes. From the third year after sowing, the plant begins to form flowering peduncles.

Rhizome division

The fertile rhizomes are those obtained from plants older than two years of age, succulent, free of blows and wounds. For cutting, a sharp tool is used -knife or scissors- free of dirt and plant debris, previously sterilized.

The cut is made along the point of union of the main rhizome, confirming a vegetative bud in each section. By this method, inflorescence production begins after two years.

Detached from suckers

The technique consists of separating or dividing the rhizomes once the first foliar apprentices and adventitious roots emerge. With this technique the viability of the new seedling to be propagated is guaranteed.

Culture

Technique used at the laboratory level in order to propagate clones identical to the mother plant free of pathogens. With this method, two years are required for the formation of rhizomes and an additional year to start production.

Requirements

The Zantedeschia aethiopica species requires the following environmental conditions for proper crop development and growth.

Temperature and altitude

The cultivation of Zantedeschia aethiopica is adapted to temperate climate conditions with average temperatures of 15-23º C, it does not support low temperatures. Likewise, it adjusts to elevational floors between 900-2500 meters above sea level.

Solar radiation

Growing gannet requires high levels of lighting to produce flowers with sturdy flower stalks and brightly colored spathes. In this regard, the optimal levels of radiation or luminous flux are around 2.7 lumen -lm / cm ² -.

Low solar irradiation or shading higher than 70% promotes the increase in size of the leaves and the flower stalk. During the winter the etiolate of these structures is frequent due to the low light intensity.

Alcatraz hybrid. Source: Derek Ramsey commons.wikimedia.org

However, the behavior of the plant at light intensity depends on the varieties and cultivars. For this reason, commercial cultivars or hybrids adapted to different light conditions have been developed.

The dwarf white calla lily is cultivated as an indoor potted plant, flowering at low light intensity. Not so the hybrids of different colors that require high levels of radiation to express their best tones.

Floors

The ideal soils for the cultivation of the gannet are loamy-clayey, which allow good water circulation, but maintain constant humidity. A porosity greater than 60% is required to allow aeration of the rhizomes and an average pH of 5.5-6.

Cultural work

The productivity and quality of the flower tips is determined by a good fertilization in each phase of the crop. In addition to balanced irrigation and adequate comprehensive management of pests and diseases.

Fertilization

The gannet, like all commercial crops, requires the application of fertilizers at the time of planting, especially the essential elements NPK. However, soil analysis is the best indicator to determine the appropriate amounts of macro and micronutrients.

In general, the application of 90 kg / ha of nitrogen is recommended two weeks after sowing. These levels allow optimal root development and prevent excess nitrogen that can affect the rhizomes.

Proper nutrition of the rhizome in the initial stages favors the development and growth of the rhizomes. Potassium promotes the appearance of apical buds and phosphorous intervenes in the rooting, flowering and thickening of the rhizomes.

Calcium applications, in addition to correcting the acidity levels of the soil, allow to firm the peduncles and flower buds. Calcium deficiency results in overturning of flower stalks and abortion of inflorescences.

Irrigation

Moisture requirements are determined by the type of soil, environmental conditions and the age of the crop. The lack of irrigation influences the adequate development of the rhizomes, directly affecting the growth of the foliar area and the quality of the flowers.

The cultivation of gannet requires abundant irrigation during the establishment of the crop, keeping the soil constantly moist. After the development of the first leaves, the frequency of watering is reduced up to 30 days after flowering.

Pests

The main insects that attack the gannet crop are spider mites, aphids and thrips.

Mites (

The spider mite, or spider mite, is a pest of the foliage of the gannet crop. The main symptom is manifested as a wilting of the young leaves, later the adult leaves tend to turn yellowish.

Tetranychus urticae. Source: commons.wikimedia.org

In the case of a high infestation, the leaves are twisted and covered with a spider web, in addition defoliation occurs. Chemical control is carried out using specific acaricides or by biological control with Phytoseiulus persimilis or Amblyseius californicus.

Aphids (

The green aphid is a polyphagous insect that damages young leaves and flower stalks, causing weakening, yellowing and occasionally death. During the infection process, aphids can be a source of transmission of viruses, such as AMV mosaic viruses.

Myzus persicae. Source: pixabay.com

Preventive control is carried out by applying cultural measures to reduce the incidence of the plague. Chemical control with systemic insecticides is effective, as is biological control with Aphidoletes aphidimyza, Chrysoperla carnea or Coccinella septempunctata.

Trips (

Flower thrips are an economically important pest in gannet cultivation. In fact, the main damage occurs in the floral spathes that deteriorate when sucking the sap, causing discoloration and deformation.

Frankliniella occidentalis. Source: commons.wikimedia.org

In case of severe attacks it can cause the abortion of the flower buds, causing the death of the plant. Preventive control is determined by weed control and the use of anti-thrips nets around the greenhouses.

Some biological controllers such as Amblyseius barkieri, Amblyseius cucumeris and Orius ssp., Have been highly effective in controlling thrips. Chemical control is only recommended when you want to quickly reduce the incidence of a severe attack, trying to use contact insecticides.

Diseases

I would alternate spp.

Alternaria is an ascomycete fungus that develops at the level of floral spathes in conditions of high humidity. The control is carried out through a systemic contact fungicide with preventive and curative action such as Iprodiome 50 PM.

Phytophthora sp.

These fungi of the Oomycetes class cause the so-called rot of the tubers, of the rhizomes and the blight of the leaves. The control of this disease is carried out through preventive measures such as cleaning tools and disinfection of the substrate.

Pythium sp.

Causal agent of rhizome rots, occurs in conditions of high levels of humidity and temperature. Symptoms are pinkish lesions on infected tissues and leaves with yellowish edges; cultural control is preventive.

Damages caused by diseases. Source: unsplash.com

Erwinia spp.

Facultative anaerobic bacterium that causes rotting of the roots and rhizomes of alcatraz plants. It mainly affects young plants and manifests as a yellowing of the foliar area; control is cultural.

Xanthomona campestris

The bacterium Xanthomona campestris causes the disease called bacterial spot characterized by necrotic lesions at the level of the leaf blade. The leaves fall prematurely and the quality of the leaf blades is reduced; control is of the cultural preventive type.

Viral diseases

Mosaic virus and spotted virus have been identified as pathogens of alcatraz culture. Symptoms are manifested in mottling and wilting at the level of leaves and flowers, and leaf rolling; control is preventive.

Physiological damage

Among the physiopathies caused by abiotic or meteorological agents are discoloration and burning of the leaves. As well as the greening of the spathe and double spathe.

Leaf discoloration

Plants can decrease the green hue of the leaves, caused by the lack of moisture in the substrate. On other occasions, the leaves take the same color as the spathes, due to the excessive application of plant hormones.

Leaf burns

This physiopathy is caused by the direct incidence of solar radiation, being severe when the leaves are moistened by irrigation. In potted plants it is advisable to avoid direct light on the plant.

Greening of the spathe

High applications of plant hormones such as cytokinins influence the green hue of spathes. Likewise, the accumulation of chlorophyll in the spathes affects this particular hue.

Double spathe

Double spathee appear when a second spathe is born from the base of the smaller, fragile main floral stem. The cause of this physiopathy is related to the inappropriate application of the plant hormone gibberellin.

References

1. Alcatraz Zantedeschia aethiopica (2018) Naturalist. Recovered in: naturalista.mx
2. Cruz-Castillo, JG, & Torres-Lima, PA (2017). 'Deja Vu': a new calla lily (Zantedeschia aethiopica) cultivar., 23 (2), 97-101. Recovered at: dx.doi.org
3. Hernández H., Eusebia. (2013) Basic Guide to the Cultivation of Alcatraz (Zantedeschia sp.) And notions for its Propagation (Reception Experience Work) Universidad Veracruzana. 27 p.
4. Posada, FC, Nieto, P., & Ulrichs, C. (2012). Flower growth, production and quality in calla lilies (Zantedeschia aethiopica (L.) K. Spreng) exposed to different quality of light. UDCA Magazine Actualidad & Divulgación Científica, 15 (1), 97-105.
5. Soto de Paz, Gabriela E. (2014) Analysis of the value chain of cartridges (Zantedeschia aethiopica) in four Departments of Guatemala (Graduate Thesis) Rafael Landívar University. Faculty of Environmental and Agricultural Sciences. 80 p.
6. Zantedeschia aethiopica (L.) Spreng. (1826) (2014) Rapid Invasiveness Assessment Method (MERI) for exotic species in Mexico. CONABIO. 11 p.
7. Zantedeschia aethiopica (2015) TropicalCoast. Recovered at: tropicalcoast.net
8. Zantedeschia aethiopica. (2018) Wikipedia, The Free Encyclopedia. Recovered at: wikipedia.org