beneficial microbes in the rhizosphere. (under construction)

  • Author Author SWvoodoo
  • Create date Create date
  • Blog entry read time Blog entry read time 4 min read
This is simply an attempt at compiling some data for my personal use mainly on the subject of maintaining a healthy rhizosphere. This may get messy.

The root zone.
Roots are made up of tough, fibrous tissues containing cellulose, hemicellulose, and lignin which branch into the soil mass (or grow media,) anchoring a plant firmly. Their basic functions are critical for plant survival: they absorb water, oxygen and minerals, and they conduct these to where they are needed.
A healthy root zone includes the natural death of older roots and the production of new ones. This cycle of death and regeneration is often mistaken by growers as a sign of disease, but so long as there are new roots developing, some root death should not be a concern.

A young plant root system should have lots of white furry root tips everywhere. A healthy mature root system will be strong and fibrous and will have a thick root mat with many white root tips underneath at the bottom.

In general the temperature should be between 68 and 72 degrees farenheit. Colder or warmer conditions can cause poor and stunted root growth

Nutrient reservoirs should always be aerated by and air pump and air stone. You can never have too much oxygen, so the more and stronger air pumps used, the better.

Root microbe symbiosis
The root itself makes up part of the rhizosphere (the endorhizosphere), while the root hairs, mucigel, and root cells that have sloughed off constitute the ectorhizosphere.

The plant actually grows its own garden of microbes, along the root surfaces. To do this, the light energy captured from photosynthesis in the leaves is channeled down the stem through the phloem vessels and out through epidermal cells to the external root surface. Incredibly, up to 80% of the total plant energy--but usually 12 to 40%--is exuded as mucigel into the ectorhizosphere as carbohydrates, amino acids, and other energy-rich compounds. As the roots grow, the roots slough off dead cells which form a slimy covering and help the roots to slide easily as they grow. This slime is a food source for many millions of beneficial microbes. This food doesn't stay around long. Billions of bacteria, fungi, algae, actinomycetes, protozoa, and other microbes feed upon this exudate.

Especially important are the mycorrhizal fungi which extend their thread-like hyphae from inside cortex cells out into the soil for several millimeters. They extend the feeding volume of the root by 10 to 1,000 times or more and extract and carry nutrients back to the root. There are two types- ectomycorrhiza and endomycorrhiza. Ectomycorrhiza are found in association with forest trees such as pines, eucalyptus and dipterocarps, while endomycorrhizal associations are formed in horticultural, forest and agronomic crops

In return for the release of nutritional substances from plant roots, microbes themselves produce chemicals that stimulate plant growth or protect the plant from attack. These substances include auxins, enzymes, vitamins, amino acids, indoles and antibiotics. These complex molecules are able to pass from the soil into plant cells and be transported to other parts of the plant, with minimal change to chemical structure, where they can stimulate plant growth and enhance plant reproduction. They may also play a role in enhancing the nutritional composition of the plant. As these molecules are released into the rhizosphere, they serve as food and growth stimulants for a certain mix of microbes.

This characteristic chemical soup stimulates the development of a select, beneficial company of root-dwelling microbes. This microbial population colonizes the root zone, producing certain chemicals that inhibit the growth of pathogenic species. These organisms are also instrumental in supplying the plant’s unique nutritional needs .

The Bennies!!!

Bacillus
Bacillus play a role in the conversion of unavailable forms of phosphates into plant available forms. With increased levels of plant available phosphorous, Bacillus strains become less effective. However, it may continue to provide hungry blooms with phosphorous if it should become otherwise unavailable or “locked out”.
Bacillus subtilis is known to inhibit pythium and is found in Hydroguard.

Mychorhizal Fung
M y•cor•rhi•zal - The symbiotic association of the mycelium of a fungus with the roots of a seed plant. They are especially effective in providing nutrients to plant roots. These are certain types of fungi that actually colonize the outer cells of plant roots, but also extend long fungal threads, or hyphae, far out into the rhizosphere, forming a critical link between the plant roots and the soil. Mycorrhizae produce enzymes that decompose organic matter, solubilize phosphorus and other nutrients from inorganic rock, and convert nitrogen into plant available forms. They also greatly expand the soil area from which the plant can absorb water. In return for this activity, mycorrhizae obtain valuable carbon and other nutrients from the plant roots.
Mycorrhizal plants are often more competitive and better able to tolerate environmental stress.

Nitrosomonas Bacteria
Species of aerobic bacteria which converts ammonia to nitrite. Will acclimate to changes in water quality, but activity is reduced during acclimation which can lead to a build up of ammonia.
Nitrosomonas eat ammonia, they convert plant available ammonium (NH4) to unavailable nitrite (NO2).

Nitrobacteria
These bacteria convert the nitrite (NO2) resulting from the nitrification above into nitrate (NO3-), an important form of Nitrogen that all plants need.

Streptomyces
Bacteria that secrete a variety of compounds including antibiotics that prevent and control root zone pathogens. A closely related species of Streptomyces produces the antibiotic that we use, streptomycin. Many studies demonstrate the bacteria’s effectiveness at controlling root diseases, and select foliar diseases. An interesting consideration noted in one study is that they will also reduce levels of some nitrogen fixing bacteria in the soil.

Trichoderma
Strains of Trichoderma are found naturally occurring in many soils can play a role in the prevention and control of root pathogens, ultimately providing a healthier soil environment which can lead to higher yields. Proteins in Trichoderma can degrade chitin, which is a structural component found in pathogenic fungi such as powdery mildew and in insects.
The trichoderma help to form a protective layer around the root system, helping to fend off invading pathogens, etc. CANNA's Coco Growing Media is innoculated with Trichoderma.

Comments

So If I maintain my air at 75f and currently my water (HYDROPONICS) 72f.

I plan to install a water chiller to maintain the water temperature around 68f?

What do you recommend?
 
Last edited:
A chiller is definitely a wise investment especially for dwc. Over 70f the ability of water to carry oxygen is greatly reduced opening the doorway for all sorts of anaerobic baddies.
I have seen many diy chillers and there are many available on li
What hydro system do you have planned? Systems such as
Topfeed to waste and flood and drain a very good at supplying the nutrients your plants need witout the high risk of disease as they allow the roots plenty of "dry" time to absorb lots of that much needed o2.
 
Last edited:

Blog entry information

Author
SWvoodoo
Read time
4 min read
Views
100
Comments
3
Last update

More entries in Member Blogs

More entries from SWvoodoo

Back
Top Bottom