Reproduction of Ferns by Spores

 

This one is my first test of reproduction of a fern by spores. I have chosen the fern Phyllitis scolopendrium

by the abundance of its spores and the great size of its sorus, which facilitates the experiment.

 

At the end of September, with the high environmental humidity in first autumnal rains, the spores of Phyllitis scolopendrium are mature and they are given off with facility with the slightest breeze, than it takes them flying far from its mother, to colonize new territories.

 

For seeding the spores it can serve a simple lunch basket of plastic transparency, in which we will put 3/4 of mixed commercial vegetal land with 1/4 of natural land (in my case argillaceous and calcareous majorcan land). About four centimeters of land will be sufficient. We tightened the land with the fingers and we watered it without exaggerating, so that it is quite humid, but not flooded. It is not necessary that we do holes of drainage to the lunch basket, because it is advisable that the land does not lose humidity, since we will not return it to water until within about two months. If we want to avoid the growth of mosses and fungi, we can sterilize the humid substrate in the microwaves. About five minutes to the Maxima power will be sufficient. In this case I have not sterilized the substrate and I have not had problems.

With no need to cut frond, we incline it upwards with back side within the lunch basket and with a teaspoon we scrape the spores, distributing them by the land surface.

The spores are deposited on the land as a fine brown layer. They are left without covering with land.

If the cover of the lunch basket is transparent, we close it with her. In opposite case it is covered with a transparent crystal and it is placed in a very illuminated place, but without direct sun and without wind. The sweet temperatures of the beginning of the Autumn are ideal for the germination of the spores. It does not agree that we remove the crystal or the cover, except to verify every several weeks the evolution of the spores. The ferns were the first plants with stem that appeared on the Earth and evolved in a very poor oxygen atmosphere and a high humidity above 90%, reason why we must recreate a similar atmosphere within the lunch basket.

To the 21 days we opened the lunch basket and we verified that all march as planned. The spores have germinated and a fine green layer has formed on the land. They are the prothallus in miniature, called PROTONEMATA, like a very small mass of cells without a definite form,  that will be growing throughout the next weeks, until becoming clearly visible.

Here we can see the fine green layer formed by the spores just germinated. We do not have to add water and we must to close the lunch basket immediately. We return it to place in the same site and wait for several weeks to touch it.

Thirty days past from seeding of the spores, the progress of the green layer is evident.

To the 42 days the green layer has grown vigorously, principally in the more elevated zones of the surface of the substratum, perhaps by the greater degree of luminosity than they receive.

A near photo allows us to distinguish the smallest PROTHALLUS or rounded GAMETOPHYTES, like tiny scales of fish. They are the haploid form of ferns, with half of the chromosomes. If the substratum follows humid, we did not add water. In case we believe it necessary, we pulverized the surface with the possible cleanest water. We return to cover the lunch basket with the crystal and we placed it in a lightly more illuminated place, but without direct sun.

After sixty days some prothallus or gametophytes have grown enough, whereas others apparently have died. Only will survive the fertilized gametophytes, that is to say, their oosphere, the female gamete, was fertilized by an anterozoide, the male gamete.

Seventy-five days past from seeding, the prothallus every time are greater. Here you can see the high humidity of the substrate, which facilitates the movement of anterozoides. They are flogged and they swim like fish, attracted by the smell of malic acid emitted by oosphere, which is for them as a delicious and irresistible fragrance, a fitopheromone.

They have spent a little more than 7 months from seeding, that is, 216 days and the first SPOROPHYTES bud with its tiny fronds of clear green color that they leave the fertilized feminine prothallus. They are the diploid form of ferns. We must to maintain the lunch basket covered several months more.

Here the sporophytes or true ferns are appraised better. They are possible to be seen filaments of fungi that apparently do not harm the good march of the process.

 

Detail of tiny fronds like rounded small leaves of clear green color with small petiole, budding from the prothallus or gametophytes, that are like small leaves of lettuce of dark green color.

Already 8 months ago I seeded the spores. The sporophytes are more and more great.

Here the tiny previous ferns can be seen from more close. The radial lines of the small fronds are very peculiar.

They have spent 270 days from seeding of spores and finally the day of the culmination of the process, the perhaps more delicate moment, the transplant of the small ferns to individual flowerpots has arrived. For it, with the aid of a coffee spoon, they are removed small groups of ferns with its respective land and small roots and they migrate by far well-taken care of and much delicateness to tiny flowerpots with vegetal land. When growing so concentrates it is very difficult to separate them one by one, reason why together ones in the same flowerpot can be seeded several, since some always can die.

Soon they are placed in a great lunch basket with a little water at the bottom so that the land of the flowerpots stays well humid, because it does not agree to water them by above, is better than the water from down by capillarity arrives to them. The lunch basket is covered and it is placed in the same place, so that the trauma of the transplant affects to them less possible. Little by little it is opened the lunch basket to accustom the ferns to the external atmosphere.

Here it is possible to be seen the real size of the fern and the flowerpot.

And this is the final result after a long year. Now only lack sow in natural habitats suitable.

Here you can see a nice and vigorous fern, in this case planted in a flowerpot pressed cellulose, which facilitates their transplant in nature. Now only remains simply digging a small hole in the ground and sow it.

And here is the culmination of the whole process: the repopulation of this beautiful fern in their natural habitat, very near their progenitor.

 

Other cultivated ferns