Plants require a wide range of minerals in order to grow and flourish, and one of these is iron. From the perspective of a micronutrient, iron is required at a relatively high level. This is in part because of a number of plant enzymes require iron to function, however the largest requirement for iron is for the synthesis of chlorophyll, which is essential for photosynthesis – this is the ability of a plant to convert water, carbon dioxide and sunlight into glucose.
Surprisingly, iron is not actually part of the chlorophyll itself; instead chlorophyll requires magnesium, which is another essential micronutrient. The inability to make chlorophyll is why an iron deficiency (otherwise known as chlorosis), shows up as sickly, yellow coloured leaves.
So although plants only need small amounts of iron to be healthy, that small amount is crucial. Although iron is the fourth most abundant molecule in the earth’s crust, its extreme insolubility can often make it a limiting nutrient, however bacteria have a special way to obtain even the smallest available iron, and plants make use of this.
Bacteria secrete small molecules called siderophores, which are iron-chelating compounds that transport iron across cell membranes. Siderophores have an incredibly high affinity for iron, so they can bind even the smallest amount. The production of siderophores is essential for many bacteria, including those that cause disease. In fact, limiting iron is actually a defence mechanism used by the human body to try and reduce pathogens from growing.
So these siderophores bind the iron molecules, and these iron-loaded compounds can then be taken up by the bacteria around the roots of the plants. More importantly, some plants can also take up these siderophores. In this way, the plants actually hijack the bacterial siderophore for their own use.
An additional benefit is that by beneficial bacteria producing these siderophores they can actually deprive pathogens of iron, thereby inhibiting the pathogen’s ability to grow and cause disease. It’s another example of how plants and the microbes have co-evolved to help each other.
It really is fascinating to see the relationship that exists between plants and microbes, and bacterial diversity in the soil is the key for this type of successful interaction. The best way to achieve this is through the use of organic material – whether this is a compost, an organic pellet such as Neutrog’s Seamungus, or even better, using a microbial inoculant such as GOGO Juice. These things all help to unlock the many benefits a diverse and active microbial population can provide for your plants.
About GOGO Juice – GOGO Juice is literally teeming with beneficial micro-biology and is essentially a pro-biotic for your soil and plants. GOGO Juice combines the “catalystic” power of providing a wide diversity of beneficial bacteria and fungi with the well documented benefits of applying kelp and humates. Applications of GOGO Juice provide a huge boost of the living micro-biology necessary for your soil and plants to perform at their optimum level, increasing their ability to resist pest and disease and to withstand &/or recover from, heat stress and frost.
About Seamungus – Seamungus is a soil and plant conditioner, manufactured by combining the very best of composted raw materials – seaweed, fish, humic acid and manure. It is also a health tonic and planting food for all plants including natives, lawns and bare-rooted roses. Seamungus undergoes a unique composting process, specifically developed to stabilise the nutrients, maximise nutrient availability and to ensure the product is free of any parasites, pathogens and weed seeds. Most importantly, the resultant product retains the microbiology necessary for a ‘living’ product. Whilst Seamungus contains a wide range and good levels of plant nutrients, it is perhaps the additional unique properties contained within seaweed that provide the catalyst for providing higher yields of sustained quality. Seamungus will help your plants resist heat, drought and frost, along with pests and disease. It will retain up to 70% of its own weight in moisture – significantly increasing the soils ability to hold onto water and nutrients.
Seamungus and GOGO Juice are available at good garden centres and hardware stores.