Reproduction and life cycle

Male flowers

Female flowers

Glassworts are perennials,^[8] meaning that they go through many reproductive cycles and they do not necessarily need to produce genetically unique seeds all the time. For this reason, they often use ramets to propagate clonally. They make genetically identical copies of the healthiest organisms to spread quickly and asexually. When growth is strong and the environment is right, glassworts will produce genets, a genetically unique individual through seeds in order to keep the population diverse and evolving. Ranets often remain connected to the parent plant in order to survive in harsh conditions until they are fully developed and do not have enough nutrients and water to survive on their own. Seeds generally germinate during the early spring when temperatures begin to warm.^[9]

Flowers

Salicornia quinqueflora is characterized as gynodioecious, meaning that there are populations containing only hermaphrodite plants as well as populations containing both female and hermaphrodite plants. Most populations are entirely hermaphrodite except for the coasts of Nelson & Foxton, Tasman Bays, and the central regions of Otago in New Zealand. For the hermaphrodite flowers, they are protogynous. This means that the female stigma matures before the male anther to prevent self-fertilization. For these hermaphrodites, the stigma protrudes 1–2 days before the anther, and the stigma are then visible for 4–6 days. Anthers are revealed individually, one at a time. Anthers open up in the early morning to release pollen. This pollen is then distributed by wind. The flowers produce no nectar and are generally not pollinated by insects.^[6] Although, introduced honeybee, Apis mellifera, has been recorded visiting the flowers of the plant and collecting pollen on parts of its body, so this species is thought to possibly help spread pollen.^[10] For the female flowers, the stigma protrudes at the same time as the anthers of the hermaphrodite plants. This allows the pollen from the hermaphrodite plants to fertilize the female plants, and the life cycle can begin.^[6]

Natural global habitat

Salicornia quinqueflora is not endemic to New Zealand.^[15] In New Zealand it is found mostly on the shoreline in regions throughout the North Island. In the South Island S. quinqueflora is widespread on the east coast, but isn't found on the west coast.^[16] In Australia it occurs on the south west and south east areas, and also in parts of the Nullarbor Plain, and part of the east coast of Cape York Peninsula.^[17]

New Zealand range

In New Zealand, the species is found in mainly coastal areas. It can be found on all islands of New Zealand – including Stewart and the Chatham Islands. Glasswort grows on both coasts of the North Island and down the east coast of the South Island. Interestingly, it is also found in Central Otago, in two locations, roughly 70 km inland.^[3]

Habitat preferences

The preferred habitat of Salicornia quinqueflora is anywhere where salty water tends to be – so along coastlines, salt marshes, sandy beaches and rocky areas.^[8] It grows below and above the high tide mark along the coasts.

Soil preferences

The species is a halophyte,^[5] so it prefers soils with high salinities. This is the main factor determining its success. It is typically found in areas with high moisture levels because of the high salinity of the soils near coastlines; however, glassworts are tolerable to a wide range of soil moistures. They can handle areas with completely dry soil and soils that are completely water logged.^[9] Salicornia quinqueflora has a healthy population in Otago, where it is extremely dry and arid. It also has a large population on the extremely wet coastlines of Nelson.

Environmental preferences

Like other halophytes, Salicornia quinqueflora can handle a wide range of temperatures and are evolved to handle sudden environmental changes. Producing offspring through clonal reproduction allows them to survive in conditions that are less than ideal .^[9] The preferred climate type is warm-temperate and subtropical regions .^[5] where they can easily reproduce through seeds to keep populations genetically stable.^[9]

Invasive species

The introduction of invasive species into the endemic regions for beaded glasswort are a major cause of habitat loss.^[5] Non-native species tend to grow quicker and faster than the native glasswort, allowing them to easily overtake their habitats. One example of this is in Victoria, Australia where Invasive Cordgrass (Spartina spp.) has changed the makeup of the intertidal sediment flats. The introduction of cordgrass caused these habitats to transform into marshlands. The previous intertidal habitat was important for the survival of the glasswort species, so the transition to marshland left the native glasswort without its habitat.^[18]

Glasswort gall mite

The glasswort gall mite, Aceria rubifaciens, was discovered in Auckland in 1948 and rediscovered in 2013 in an estuary near the Firth of Thames. This tiny, endemic mite only feeds on the glasswort, which the feeding causes pocket galls on the fresh, young stems. The mites live inside the galls which offer them protection from larger predators and weather conditions.

There is not a lot known about these tiny mites, mainly because they have only been found on Salicornia quinqueflora. So far it has only been found in the North Island, but it can be assumed that it would affect the other populations throughout New Zealand.^[19]

Other predators

Glasswort is also edible and palatable, so is known to have been consumed by both animals and humans. It could then be argued that both animals and humans are also considered predators of glasswort.^[15]

Habitat in inland Otago

Maniototo Plain as unusual inland habitat for Glasswort

Salicornia quinqueflora has been found growing in inland regions of Central Otago, the Maniototo Plain. This is odd because of its liking for salty soils near coastal areas. The Maniototo plain has developed highly saline soils due to the extreme dryness of the area. As rocks erode, the soil became more and more salty, and there was not enough rain to wash the salt away. This left the soil salty enough to support the glasswort. As the seeds were transported into the area by birds, the plant began to grow in the inland region.^[3]

Food Source for orange-bellied parrot

The orange-bellied parrot of Australia relies heavily on glasswort as its main source of food.

One species known to rely heavily on the glasswort is the orange-bellied parrot (Neophema chrysogaster). This parrot is critically endangered, having only around 180 individuals left in the wild. This native Australian bird feeds primarily on the seeds of Salicornia quinqueflora. As habitats for the glasswort decline due to human development, it becomes harder for the parrot to find the amount of seeds it needs to survive.^[20]

Glasswort use in recipes

Glasswort, apart from being a subshrub that can grow in incredibly harsh conditions, is also an edible plant.^[21] It is recommended to eat the fresh, young, upper parts of the glasswort stems raw, as they are tender and more flavourful. People are able to eat glasswort on its own, like in a salad, or mixed with other salad ingredients. It can also be used as a garnish with seafood – similar to how restaurants use parsley or watercress. The natural salty content and flavor means that glasswort is good in soups or stews for extra flavour, or can be served as a hot vegetable as well. Using the fresh parts of the stems, glasswort can also be pickled – but very carefully, as like anything when pickling.^[21]

There are also certain medicinal properties to glasswort. It is high in Vitamin C, Vitamin A and the B-complex vitamins and has also been described as helping flatulence and digestion.^[21] There are also certain glycosides, the bioflavonoid quercetin and isorhamnetin, which have been mentioned as possible aids for cancer.^[21]