Full, fragrant blooms bursting from a fantastic harvest is every grower’s dream. After all, it’s time to reap the fruits of your uphill struggle. Once every aspect of your growing system is optimized, bigger outputs are subject to providing balanced soluble salts, maintaining oxygen concentration and stabilizing pH range. But what if all these wonderful ingredients are not reaching the plants or not being precisely absorbed by plant roots and are immediately swept out? This is a very crucial fact but mostly overlooked by most hydroponic growers.
It’s essential to give the roots every advantage they can have to feed your plants and allow them to thrive. The area in the region of the roots undergoes abundant biological and chemical activities. It’s not as much about retaining root health as it is about maintaining the conditions in the rhizosphere, which is the region around the plant roots. So, there is a hidden secret to obtaining bulky root mass and this secret is in the hands of none other than our surrounding environment.
Nature’s most copious harvest stimulators are a group of beneficial microorganisms that can increase root mass by many percents. Billions live in fertile soil, but few to none are found in the untreated hydroponic system. The microorganisms in the rhizosphere feed on the exudate of the roots. Managing the rhizosphere and the conditions in the nutrient solution are critical to maintaining plant health.
Types of Beneficial Microbes
The soil is a natural habitat for a range of flora and fauna. Geologically, around 30,000 taxonomic varieties of microbes have been identified. These tiny creatures are categorized on the basis to their size; among which the microfauna constitute an important class and play a vital role in crop productivity. Microfauna is a term primarily targeted at moieties of size in the range from 1 to 100 micrometers. This group involves various classes among organisms such as bacteria, fungi, protozoa, and rotifers, etc. Their presence is indispensable for decomposing organic matter and increasing essential macronutrients (nitrogen, phosphorus, potassium, sulfur, calcium, and magnesium) and micronutrients (boron, copper, chlorine, iron, manganese, molybdenum, and zinc) availability to crop plants. Some of the commonly used beneficial microbes in agriculture include Rhizobia, Mycorrhizae, Azospirillum, Bacillus, Pseudomonas, Trichoderma, Streptomyces species, etc.
Broadly speaking, these beneficial microbes can be distributed into two classes – bacteria and fungi. Beneficial bacteria is a group of free-living bacteria that colonize the rhizosphere and benefits root growth. It’s a fact that inoculating the plant roots with beneficial microorganisms helps to create healthier growing mediums and more sound root systems. A significant increase in yield of agronomically important crops in response to inoculation with beneficial bacteria has repeatedly been reported.The microbes help fix atmospheric nitrogen to ammonia and further to nitrates, increase root mass considerably, hence, increasing water and nutrient uptake resulting in higher yields. The bacteria enter the plants and release plant growth hormones such as auxins and cytokinins inside the plant sap which promote growth. They also induce a much larger production of chlorophyll which is very useful to maximize hydroponics light condition. Resistance to various diseases is also higher in plants fed with this group of micro-organisms.
- Decomposers – The class of microbes break down the organic matter and maintain viability by producing detritus material through their natural processes. These includes bacteria from genera such as Streptomyces, Bacillus, Arthrobacter, Paenibacillus, and Clostridium.
- Nitrogen fixing bacteria- The microbes help fix atmospheric nitrogen to ammonia and further to nitrates.
- PGPR- Plant growth-promoting rhizobacteria (PGPR) are a group of free-living bacteria that colonize the rhizosphere and benefit root growth. Bacteria of diverse genera were identified as PGPR of which Bacillus and Pseudomonas spp. are predominant. PGPR exert a direct effect on plant growth by the production of phytohormones, Solubilization of inorganic phosphates, increased iron nutrition through iron-chelating siderophores and volatile compounds that affect the plant signaling pathways. Additionally, by antibiosis, competition for space and nutrients, and induction of systemic resistance in plants against a broad-spectrum of root and foliar pathogens, PGPR reduce the populations of root pathogens and other deleterious microorganisms in the rhizosphere, thus benefiting the plant growth
Fungi – Mycorrhizas are a mutually beneficial relationship between the root system of a plant and beneficial fungi that are present in the soil. They can be of two types: Ecto (external) or Endo (internal) mycorrhizas. When the fungi grow around the roots and cover the root surface, they are called ectomycorrhiza. When they grow inside the root, they are called endomycorrhiza
How microbes boost crop productivity?
An assembled microbial community in the solution improves plant performance and productivity in the following ways: exclusion of plant pathogens, resistance to infection, and plant-growth promotion.
A detailed description is as follows:
- Nutrient availability: Aerobic Bacterias release nutrients locked in organic or inorganic form to its more available version. Saprotrophs or beneficial fungi are also known to extract fat-soluble nutrients through solubilization Actinobacteria play a fundamental role in the decomposition of organic matter
- Plant growth promotion: Beneficial microbes such as PGPRs, secrete metabolites that trigger the release of plant hormones. Some PGPRs are known to promote root growth by lowering indigenous ethylene levels in the micro-rhizome environment.
• Beneficial microbes also play a significant role in solid wastes and sewage management.
• Beneficial microbes increase plants tolerance to different environmental stresses (drought, heat, cold, salinity, etc.) and increase plant resistance to insects and diseases attacks.
• Beneficial microbes not only improve crop growth and productivity by increasing photosynthesis and producing hormones and enzymes but also improve crop quality by controlling different insects and various plant diseases.
• Beneficial microbes reduce the use of chemical fertilizers and thereby reduce environmental pollution caused by chemical fertilizers.
• Beneficial microbes reduce the cost of production, and so increase grower’s income and profitability.
• Stabilization of soil aggregates: Arbuscular mycorrhizae, a beneficial fungus produces glomalin, a protein that binds to soil particles and stores carbon and nitrogen. Beneficial microbes are also known to improve soil structure.
Adding microbial supplements to Hydroponics garden
Beneficial microbes are therefore paramount for increasing crop productivity, profitability, and sustainability. Applications of microbial supplement in hydroponics improves plant health and yield. Thus, picking up the right microbial supplement is crucial for bigger harvest, so, look for products that are tailor made and specially designed for your grow room.
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