Abstract:

In an agroecological approach of permaculture or agroforestry, it is desirable to cultivate plants capable of naturalizing.

However, cultivated lettuce (Lactuca sativa subsp. sativa) presents a very strong barrier to spontaneous propagation: its flower heads remain closed after the seeds have matured, so the latter cannot fly away as those of their wild ancestor would do. (Lactuca sativa subsp. serriola).

While this characteristic resulting from human selection is essential in conventional cultivation systems since it facilitates the harvesting of seeds and avoids the uncontrolled propagation of plants, it is however less relevant in the context of an agroecological culture, based on the processes and ecosystem functions.

This trait can be eliminated through hybridization with it’s wild ancestor: Lactuca sativa subsp. serriola.

As part of this project, in 2022, four lines resulting from hybridizations between wild and cultivated lettuces were produced by Joran's Seeds & Research.

Four open-growing, seed-reproducible lettuce cultivars were used as maternal parents, and wild lettuces (Lactuca sativa subsp. serriola) from the local flora of the Ardèche department in southern France as paternal parents.

Both botanical varieties of the serriola subspecies were used: var. serriola and var. integrifolia, in different combinations.

Ultimately, this project aims to produce naturalizable winter lettuce lines.

Developed for sowing in autumn, very easy to grow in open fields, they will not require irrigation or treatment during cultivation; and will be able to naturalize thanks to the release of their seeds.

Harvested leaf by leaf, as “looseleaf” lettuce at the rosette stage, they can then:

- either be consumed in the “celtuce” type, once erected 30-40cm.

- either be left in place, as reproductive plants, to re-seed themselves according to the wind.

However, the production of commercial quantities of seeds remains possible by growing plants under cover. It will then be possible to harvest almost all of the seeds.

The largest collection of perennial leeks (𝐴𝑙𝑙𝑖𝑢𝑚 𝑎𝑚𝑝𝑒𝑙𝑜𝑝𝑟𝑎𝑠𝑢𝑚).

joransseedsresearch@gmail.com

Joran's Seeds and Research

Research and development of innovative, perennial vegetable lines, specifically designed for permaculture and low-irrigation cultivation.