근원종

근원종

예전부터 전하여 내려오는 농작물이나 가축의 품종. 다른 지역의 종자와 교배되는 일이 없이, 어떤 지역에서만 여러 해 동안 길러지거나 재배되어 그곳의 풍토에 알맞게 적응된 품종을 일컫는다.

wild species of corn:teosinte

Origin: Mexico, Central America

Lifespan: Perennial plant

Around 9,000 years ago, humans came into contact with wild teosinte in the Balsas River valley in southern central Mexico. After undergoing various improvements by humans, modern corn (maize) was eventually developed. Teosinte has high resistance to viral and fungal diseases of corn, as well as corn insect pests.

It has the characteristic of having 10-12 small, hard fruits attached, resembling an ear of corn. There are multiple branches, each with a unique and small female flower cluster. As the flower stalk matures, it forms two tiers of 5-10 triangular or trapezoidal, black or brown, detached segments, each containing a single seed. Each seed is enclosed in a very hard fruit wall, composed of the sunken portion of the flower stalk and a hard lower glume.

While teosinte is a wild relative of corn, unlike corn, it has tolerance to waterlogging. In response to soil waterlogging, the outer cell layers of teosinte roots accumulate more lignin and suberin, increasing gas impermeability of the root surface and greatly reducing radial oxygen loss compared to corn roots.

From the perspective of adaptation and evolution, teosinte's unique breeding method allows active cross-pollination with nearby individuals, which is considered a good way to increase the genetic diversity of corn. This trait may have helped teosinte become a stronger individual and survive in the wild.

The hard seeds of teosinte protect the seeds from being digested by ruminant animals that feed on it, and help distribute the seeds through their excrement.

wild species of rice:rufipogon

The current ancestor of rice is estimated to have appeared on Earth around 140 million years ago and underwent a long evolution, becoming cultivated rice around 15,000-10,000 years ago. Rice has diversified into the African Oryza barthii and the Asian Oryza rufipogon.

Oryza rufipogon

Lifespan: Perennial, annual

As an undomesticated species, it can survive without human intervention. Wild rice ripens and shatters more quickly than cultivated rice. The stems of wild rice are more fragile and have a more rounded cross-section than cultivated rice. Oryza rufipogon has a spreading habit. It also has a higher seed shattering rate compared to cultivated rice. It has a higher degree of seed dormancy.

Unlike cultivated rice, Oryza rufipogon has an erect form, with a height ranging from 150-400 cm. The lower part of the stem is spongy. The nodes are also hollow and without hairs. It is mainly distributed in tropical and subtropical regions. The wild rice has a very well-developed abscission layer from the epidermis to the vascular bundle, allowing the mature seeds to detach more easily.

In the process of adaptation and evolution, the erect form of Oryza rufipogon is advantageous. The erect form can more efficiently receive light from the sun, facilitating convenient gas exchange for photosynthesis. It can also utilize space more efficiently, allowing for faster growth. The erect form is also more stable against wind and external impacts, enabling the plant to grow to a larger size. This is why Oryza rufipogon can grow up to 150-400 cm, while cultivated rice averages 50-100 cm. Although more fragile than cultivated rice, the lighter and smaller seeds of Oryza rufipogon allow it to grow in an erect form. This tall stature provides a competitive advantage over other plants.

The deeper roots of erect plants can also improve soil structure and promote microbial activity in the soil. Oryza rufipogon's more developed abscission layer was likely advantageous for dispersing its seeds in the wild. These distinctive characteristics of Oryza rufipogon compared to cultivated rice appear to have been beneficial for its survival in the wild.

wild species of Strawberry:Fragaria virginiana

Lifespan: Perennial

Cultivation season: Winter

Type: Herb

This plant has a height of 10 cm and a crown diameter of 30-60 cm.

It has green, trifoliate leaves, with each leaf being an elliptical shape about 10 cm long and 4 cm wide. The leaf edges have coarse serrations. The plant produces flowers with 5 white petals surrounding a yellow pistil. Below the petals are 10 small green sepals.

The fruit is red, fleshy, and contains many small "seeds" (achenes) inside. The wild strawberry fruit is smaller than cultivated strawberries.

Fragaria virginiana is an octoploid with a genome structure of AAA'A'BBB'B'. The A-genome is derived from a diploid ancestor related to Fragaria vesca, while the B-genome is thought to be derived from Fragaria iinumae.

From an adaptation and evolution perspective:

The wide crown diameter of F. virginiana relative to its height suggests an adaptation to maximize photosynthesis. A broader canopy allows for more efficient carbon absorption and oxygen release, benefiting the plant's growth. The red fleshy fruit is likely an evolutionary adaptation to encourage consumption by animals, which can then naturally disperse the seeds.