Skip to main content

Gametophyte evolution, Hymenasplenium murakami-hatanakae Nakaike, the fifth family to produce independent gametophytes

NEWS - Nakaike spleenwort (Hymenasplenium murakami-hatanakae Nakaike) can survive for long periods without a spore-producing sporophyte. Researchers report that H. murakami-hatanakae undergoes alternation of generations as an independent gametophyte, the only one in the suborder Eupolypods II (Aspleniinae).

Gametophyte evolution, Hymenasplenium murakami-hatanakae Nakaike, the fifth family to produce independent gametophytes

Aspleniineae appear to have evolved independent gametophytes to adapt to rocky and isolated environments. The research opens the way to elucidating gametophyte evolution and other important questions in plant ecology. A diversity of fern species reproduce and fill environmental niches.

Noriaki Murakami of Tokyo Metropolitan University in Tokyo, along with a team from Showa University in Yamanashi, and the National Museum of Nature and Science in Ibaraki, collected specimens from Izu-Oshima Island in southeastern Japan, and used DNA analysis to trace the generations.

Aspleniineae is a suborder called Eupolypods II that includes 30 percent of the ferns on Earth and is a rare group. Studying this species further promises to reveal more about how ferns diversify and adapt.

Plants and algae have a complex cycle that they use to reproduce. Each species has two generations in the cycle, a sporophyte that has two sets of chromosomes (diploid) and a gametophyte that has one (haploid). When the gametophyte matures, it produces gametes to produce a diploid zygote.

The zygote continues to divide and eventually becomes a sporophyte. The sporophyte produces spores through a process that halves the number of chromosomes. These spores divide and develop into gametophytes, and the cycle continues.

Sporophytes and gametophytes generally depend on each other for nutrition, but ferns have a special place in biology because they are independent of each other, raising the intriguing possibility that they can live long periods without each other or live as independent gametophytes.

Murakami and his team collected H. murakami-hatanakae that live in dark, humid environments on rocks along warm-climate rivers in Japan and Taiwan. The team collected specimens on Izu-Oshima Island and used DNA techniques to identify the species. DNA extracted from chloroplasts to identify sporophytes and gametophytes was then compared. They found that the gametophytes of this species can survive for long periods in an environment completely isolated from the spores.

Original research

Yoneoka, K., Fujiwara, T., Kataoka, T. et al. Morphological and functional evolution of gametophytes in epilithic Hymenasplenium murakami-hatanakae (Aspleniaceae): The fifth family capable of producing the independent gametophytes. Journal of Plant Research (2024). DOI:10.1007/s10265-024-01553-0

Popular Posts

Bugang (Clerodendrum calamitosum)

Bugang ( Clerodendrum calamitosum ) is a species of plant in the Lamiaceae family. It is an erect shrub, growing up to 1 meter tall, with cylindrical, green stems and white hairs. The leaves are opposite. The leaf blade is oval, wavy, with a central main vein with numerous pinnate minor veins, and serrated margins. The leaves are up to 9 cm long and 7 cm wide. The petiole is up to 2 cm long. The flowers are star-shaped, white, up to 3 cm in diameter and up to 6 cm in total length. The fruit is round, dark green, turning black when ripe. TAXON Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida Order: Lamiales Family: Lamiaceae Subfamily: Ajugoideae Genus: Clerodendrum L. in Sp. Pl.: 637 (1753) Species: Clerodendrum calamitosum L. in Mant. Pl. 1: 90 (1767) HETEROTYPIC SYNONYMS Clerodendrum fastigiatum (W.Hunter ex Ridl.) H.J.Lam in Verben. Malay. Archip.: 317 (1919) Volkameria alternifolia Burm.f. in Fl. Indica: 137 (1768) Volkameria fastigiata W.Hunter...

Plumeria rubra and Plumeria obtusa, the differences

SPECIES HEAD TO HEAD - The genus frangipani trees ( Plumeria Tourn. ex L.) has only 18 officially recorded species and two very similar species, frangipani ( Plumeria rubra L.) and white frangipani ( Plumeria obtusa L.). Both have the same habitus, flowers and fruits and are difficult to distinguish. The leaves of both species have slightly different shapes. Therefore, the leaves are very important to distinguish the two species, especially the shape of the tip. P. rubra has simple, lanceolate leaves with acute tips. P. obtusa has simple, elliptic leaves with rounded tips. By Aryo Bandoro Founder of Dlium.com . You can follow him on X: @Abandoro . Read more: Plumeria rubra Plumeria obtusa

Durian (Durio zibethinus)

Durian ( Durio zibethinus ) is a species of tropical plant in Malvaceae, an annual tree, everlasting green but there are certain times to grow new leaves after the fruiting period is over, popularly called "king of fruit" and considered a controversial fruit where many people like, but some others are even fed up with the scent. D. zibethinus grows to 25-50 m, reddish brown bark and irregular peeling, leafy and stretched canopy. The leaves are oval shaped to lanceolate, 10-15x3-4.5 cm, sitting alternately, stemmed, taper or blunt base and taper-pointed sloping, bright green upper side, the lower side covered with silver or golden scales. Flowers and fruit Flowers appear directly on the trunk or old branches at the proximal, clustered in panicles containing 3-10 florets or flat-shaped florets. Rounded flower buds, 2 cm in diameter and long stem. Tubular petals, 3 cm long, additional petals split into 2-3 round lobes. Crown shaped spatula with a length of 2 times the ...