Smart Farming Solutions

Among the many soil microbes, bacteria and fungi play major roles in providing plants with nutrients, hormones, drought and disease tolerance and other benefits.

Bacteria

The basic function of bacteria is the reduction of complex organic compounds to simpler substances. Bacteria disintegrate plants and animals, returning basic elements to the soil and air which are used again to create new life.

Depending on the depth, moisture and temperature of the soil, bacteria population in one gram of soil can range from several million to over a billion.

Bacteria have a symbiotic relationship with plants at the root zone, a part of the soil called Rhizosphere. Most soils are low in available carbon, while soil microbes consist mostly of carbon. As a result, soil microbes are usually in a state of starvation. However, some species of bacteria at the root surfaces extract needed nutrients from the plant, including sugars, amino acids, vitamins, tannin, to name a few. Sugars provide readily available sources of carbon, while amino acids provide nitrogen.
In return the Rhizobacteria provide numerous benefits to the plant including:
• Mineralization of organic nitrogen, sulfur and phosphorous.
• Fixation of nitrogen
• Increasing root area.
• Causing oxidation-reduction reactions.
• Promoting plant growth
o Producing plant hormones
o Protecting against harmful pathogen
o Enhancing nutrient uptake and use
• Increasing breakdown of synthetic pesticides and other contaminants.
• Enhancing drought resistance.
• Improving soil aggregation/aeration.

Bacteria population numbers and diversity can rapidly increase when calcium is readily available, when soil pH increases towards neutral, and sugars and amino acids are available.

Fungi

Like bacteria, fungi play a major role in the decomposition process and the formation of humus. In fact up to 50% of the substances decomposed by fungi may become fungal tissue, compared to about 20% with bacteria.
Certain fungi have a similar relationship with plant roots as Rhizobacteria. This relationship is called Mycorrhizae. They derive a huge survival advantage by teaming with plants. Instead of competing with other microbes for decaying organic matter, they obtain sugar directly from root cells. Amazingly, they can drain 5% to 30% of the plant photosynthate production. However they provide an enormous benefit in return: their hyphae (tentacles) grow out in the soil 5 to 15 cm from the infected root, reaching into small soil particles pores, which root hairs are unable to do, thereby bringing moisture and nutrients to the plant in far greater quantity. The Mycorrhizal fungi can provide as much as ten times more absorptive surface area to the infected plant.

Unfortunately increased quantities of fertilizers and pesticides, the absence of crop rotation and the frequent tilling of the soil kills or greatly diminishes the beneficial microbe populations. Fumigation also renders a soil sterile. The result is decreased plant vigor, more susceptibility to drought and diseases and lower yield.

One way to rejuvenate the soil is by inoculating it with specific species of bacteria and fungi. Many farmers and gardeners are discovering that they can greatly decrease fertilizer and pesticides rates by incorporating inoculants on a routine basis as part of their normal and sustainable cultural practices.

One word of caution: there are many types of inoculants, be sure to choose the appropriate one for the task. For example, there are products specific for decomposing thatch/grass clippings, which is very desirable if you are a turf grower or you are one of the unlucky ones to mow your yard more than once a week during the summer. On the other hand, there are inoculants specific for plant growth and yield.

Another important point when applying inoculants: there populations grow logarithmic when food is available, which includes fertilizers. It also means that during their rapid multiplication they will compete with plants for nutrients. Therefore it is important to provide them an alternative source of food. Many farmers and gardeners apply molasses overhead or through drip irrigation on a regular basis to alleviate this problem. It is also important to reduce fertilizer rates when implementing an inoculation program.

If you are an organic farmer or gardener, inoculants along with calcium are probably your best weapons to fight off diseases and increase plant vigor and yields. The same applies to turf.

Labels: benefical bacteria, inoculants, organic farming, soil remediation