Hier het complete hoofdstuk uit het boek " Teaming with Fungi ".
Mogelijk biedt dit wat meer handvatten voor mensen die met schimmels en bacto aan de slag willen in hydro.
In een systeem met een pompje dien je wat vaker de myco's mee te geven, omdat de sporen en hyfen erg gevoelig zijn. Om die reden is het ook aan te bevelen om mycorrhiza pas aan het einde van het brouwproces toe te voegen, wanneer je een theetje wilt maken, of deze in een eerder stadium op te kweken.
Er zijn hydro kwekers die zweren bij myco/bacto en ook kwekers die liever alles compleet verschoond zien van schimmels.
"Teaming with Fungi" (2017)
Mycorrhizae in Hydroponics
Almost any plant that can be grown in soil, can be grown in a hydroponic system, from trees to fruits and vegetables. Because no soil is used, a liquid nutrient delivery system supplies all the nutrients the plants need. Why would plants also need mycorrhizal fungi ? Simply put, mycorrhizal fungi offer the same benefits in hydroponic applications as they offer in planting media and soil.
Mycorrhizal fungi are good at what they do, especially in delivery of phosphorus and nitrogen to their plant symbionts. As they do in other growing systems, fungi grown in hydroponic systems expand the effective root area into the surrounding growing substrate, be it coconut fiber, rockwool, oasis cubes, gravel, vermiculite or perlite, clay pellets, or other material. The same hyphal extension that occurs with colonized roots in soil, also occurs with colonized roots in hydroponic systems. Whether plants are growing in soil, a planting mix, or a hydroponic growing substrate, mycorrhizal fungi provide the same basic benefits to host plants:
* Inoculated roots in hydroponic systems are more resistant to pathogens, including Rhizoctonia, Fusarium, Pythium, and Phytophthora.
* Mycorrhizal fungi can create physical barriers around roots to protect them from disease and pathogenic fungi.
* Colonized plant roots branch and form more feeder roots, so more nutrients can be retrieved from the surrounding area.
* Mycorrhizal fungi grown in a hydroponic system can support mycorrhizospheric organisms that provide protective metabolites.
Mycorrhizal considerations for hydroponic systems
As with any other growing system, for mycorrhizal fungi to thrive and benefit plants in a hydroponic system, growers must use the appropiate species of mycorrhizal fungi to colonize the plants being grown. They must also consider several other factors.
A hydroponic system that intends to support colonization of roots by mycorrhizal fungi must be fully aerobic. To ensure that the fungi will survive, growers should maintain oxygen levels at 6 to 8 parts per million (for context, most tap water provides 5 ppm of oxygen). Oxygen can be added to the growing environment via air stones or bubblers. (Although hydrogen peroxide can also oxygenate water, it will kill mycorrhizal fungi and host plant tissue and should not be used).
Most hydroponic systems use some form of media to support plants, such as rockwool or expanded clay pebbles. Many scientists use a modified hydroponic system for their studies, using sand as a growing medium and saturating it with nutrient solution, but mycorrhizal fungi will grow in nearly any substrate, or even in water alone, if it provides enough oxygen.
Hydroponic growers often add phosphorus to nutrient delivery system, but an increase in phosphorus levels can result in decreasing amounts of mycorrhizal colonization. When large amounts of phosphorus are present in the system, at levels of around 70 parts per million, fungal spores go dormant and will not germinate. By monitoring phosphorus levels and avoiding adding too much fertilizer, growers can encourage the formation of mycorrhizae.
The presence of chlorine and chloramines in public water systems can also affect mycorrhizal growth. Chlorine dissipates into the atmosphere in about eight hours, but chloramines take days to evaporate and should be removed from water used in hydroponic applications. Hydroponic suppliers can provide recommendations on how to accomplish this.
The PH of the water in hydroponic systems is also important. Most mycorrhizal fungi require a PH range of 5.5 to 7 to survive. Mycorrhizal mix packaging often lists the required PH levels.
Finally, maintaining proper temperatures will maximize mycorrhizal colonization. Arbuscular mycorrhizal fungi thrive in temperatures of 24-30 °C, which is also the ideal temperature for most plants. Growers should be aware that vesicles, spores, and fungal hyphae will not survive temperatures above 49 °C. Plants would die under such extremely high temperatures as well. When storing mycorrhizal inoculants, growers also consider appropiate temperature conditions.
Hydroponic supply sources offer mycorrhizal mixes specifically designed for hydroponic systems. In these blends, spores and hyphal fragments are mixed with delivery media in liquid or powder form. To establish mycorrhizae, make sure the inoculants are in direct contact with rooted or unrooted cuttings before they are placed into the hydroponic system, or soak starter cubes in liquid formulations or granular formulations mixed with water. As in soil, the spores will germinate when they are signaled by the roots exudates. Many formulations can be added directly to the hydroponic nutrient delivery system; the particles within the mix are small enough to pass through systems without clogging up lines or emitters. Mycorrhizal formulation providers should indicate the proper ways to distribute the inoculants.
Mycorrhizal fungi do not generally reproduce in hydroponic systems, so it is a good practice to add more inoculants to the nutrient delivery system as roots develop to ensure maximum colonization throughout the life of the plant. How much more and how often ? The plants can offer the answers. Fast root and plant growth require more frequent addition of inoculants. Because it takes about two weeks for mycorrhizae to become established, application should be discontinued a few weeks before flowering for flowering crops and a few weeks before harvest for others, such as lettuces. Why waste propagules ?
Mycorrhizal Hydroponic Plant Studies
Studies show that mycorrhizal inoculation can provide many benefits to plants growing in a hydroponic system.
Cannabis (Cannabis Sativa) Claroideoglomus claroideum, C. etunicatum, Funneliformis geosporum, F. mosseae, Glomus microaggregatum, Rhizophagus clarus, and R. intraradices are succesful inoculants for cannabis growing in rockwool. Using mixes of several inoculants results in healthy plants, but studies indicate that inoculating with R. intraradices alone produces similar results.
Carrot (Daucus carota) Carrots thrive when inoculated with mycorrhizal fungi in hydroponic systems. Nutrient sprays are best. A 3-to-1 mixture of perlite to vermiculite makes an ideal substrate, as long as it is deep enough to support the particular carrot cultivar. Studies showed that inoculation with Rhizophagus intraradices BEG 141 increased the carrots' fresh weight better than use of Funneliformis mosseae BEG 167.
Cucumber (Cucumis sativus) Cucumbers perform well when inoculated with arbuscular fungi and planted in individual cell pots with a perlite and vermiculite mix. Claroideoglomus etunicatum, Funneliformis caledonium, F. mosseae, and Rhizophagus clarus can be used as inoculants.
Garlic (Allium sativum) With roots that are readily colonized, garlic grows in baskets using perlite or a perlite and vermiculte mix. Cloves can be restarted in water until sprouts and roots appear and then transferred to the hydroponic system. After inoculation with Rhizophagus fasciculatus in field studies, garlic showed increased yields and larger bulbs.
Pepper (Capsicum annuum) Using netted pots and a media mixture of perlite, peat and vermiculite, pepper plants showed increased root mass, larger fruit growth, and more accumulated nutrients after inoculation with Rhizophagus intraradices.
Strawberry (Fragaria ananassa) Many strawberry cultivars growing in a vermiculite substrate were inoculated with Claroideoglomus etunicatum, Funneliformis mosseae, and Rhizophagus intraradices. They showed better overall growth and productivity than control plants, but results varied depending on the variety.
Tomato (Lycopersicon esculentum) Inoculation with Funneliformis monosporus, F. mosseae, Rhizophagus intraradices, R. vesiculiferus, and Glomus deserticola increased fruit yield of tomato plants grown in a sawdust substrate. Inoculation with F. monosporus and F. mosseae increased plant height and dry weight significantly.
Trichoderma and Mycorrhizal Fungi
Many growers use Trichoderma species in their hydroponic systems. Like mycorrhizal fungi, Trichoderma fungi protect plants from pathological organisms and help the associated plants increase their nutrient uptake. However, Trichoderma fungi generally cycle nutrients from organic matter, while mycorrhizal fungi actively transport nutrients directly into the plant cells. These two fungi work well together and both benefit hydroponic growing systems.