Pre-seeded biodegradable textiles for landscaping and sustainable agriculture

Lettuce cultivation

Virens is a company that has been developing pre-seeded biodegradable textiles for landscaping, soil protection and renaturalisation, and sustainable agriculture for almost 30 years.

Viresco® Olus pre-seeded biofabric is used in particular in agriculture, with horticultural and aromatic species, as a technical means for “open field” and “greenhouse” horticulture.

Virens applications

Azienda Agricola Sperimentale “M. Marani” from Ravenna conducted field trials on technical means for soil protection in organic farming, with the biofabric Viresco® Olus, sown with lettuce and wild rocket.

As we know, in organic farming, defence tools are very limited and, with respect to lettuce in particular, the crop must be grown on well-drained soils since pests and fungi frequently occur as a result of waterlogging.

Different sowing techniques

Two different innovative seeding techniques were compared, the first direct seeding on soil, preceded by flame weeding, and the second indirect seeding using Virens’ pre-seeded cloths.

At the end of the test, statistical processing was carried out with factorial analysis of variance and RCBD.

Factor processing allowed the following conclusions to be drawn:

– Factor A

The comparison between sowing on soil and sowing with pre-seeded cloth showed that the pre-seeded cloth results in higher field germinability in favour of the latter.

– Factor B

The same consideration applies to commercial production, similarly, non-commercial production was significantly lower in the cloth than in the ground: this is positive and attributable to the total absence of weeds in the cloth and a better overall phytosanitary state of the crop.

– Factor C

The AxBxC interaction is non-significant for all parameters with the exception of non-commercial production, where there is synergy between cloth, species and scattering.

With regard to the soil/scattering lettuce combination, there is a strong negative interaction due not only to the presence of weeds but also to the presence of peronospora on the leaves, which are only present in the lettuce theses sown on soil.

In order to assess the differences between the test theses using a traditional method, a classic block processing was then carried out, which allowed the following conclusions to be drawn.

By examining the best performance, it was found that the combination of scattering and cloth could provide the best yield and the best result in terms of non-commercial waste.

In conclusion, the two techniques considered both present pros and cons, often in opposition, and are influenced by the period in which cultivation takes place (spring or autumn).

From the experiments conducted, the use of the pre-sowing cloth in the autumn period has shown the advantage of allowing shorter cycles, better investment regularity and, above all, excellent weed control, leading to good production in terms of quantity and quality.

On the other hand, in spring cycles, the increase in temperatures causes strong evaporation that can negatively affect seed germination, which, with this technique, is directly exposed to the air. Therefore, it is necessary to implement particularly effective “micro-irrigation” techniques that can keep the right degree of humidity constant until the seeded crop fully emerges (seeds included in the cellulosic cloth).

The spring period favours the emergence of vigorous polyannual weeds which, growing underneath the cloth, can increase it. It is therefore fundamental to implement preventive control of this type of weed.

Essential for the success of a pre-seeded crop is the careful preparation of the soil (refinement and rolling), which is indispensable for the cloth to be accepted. After the cloth has been laid, a second rolling must be carried out in order to make the bio-textile adhere perfectly to the soil. Especially if cultivation is in the spring period, it is essential to constantly monitor the moisture content of the cloth, taking care to compensate for evaporation losses with frequent light irrigation. A possible solution to this problem is to spread a layer of compost on the cloth. This layer will have the effect of retaining more moisture, thus preventing excessive exposure of the seeds to the air.

As for direct sowing preceded by flame weeding, these have the advantage, especially in spring, of not being affected by the evaporation phenomena to which pre-sown cloth is subject.

However, this technique is more prone to the presence of weeds in the middle of the crop, leading to more waste from foreign plants and consequently penalising production.

For both techniques, however, the preliminary soil preparation phase aimed at reducing the potential for weed infestation is fundamental.

A final consideration that is particularly important for application purposes is that lettuce sown in cellulosic cloth was not subject to pest attacks, unlike lettuce sown on soil.

The most plausible hypothesis is that the cellulosic layer provides a real active (mechanical) defence against the spreading organs of the peronospora.

And this form of preventive defence turns out to be a further very important plus offered by the VIRESCO® Olus pre-seeded biofabric.