All hormones are proteins but not all proteins are hormones. That’s what we learnt from our biochemistry class. We all know the function of proteins in plants and animals. Hormones make things happen. Plant growth hormones are produced by ALL crops at different stages of their growth cycle. You can think plant hormones as the FedEx of the plant world. They are messengers produced in one part of the plant body and affect different regions of the plant. Unlike humans, plants don’t have a heart that pumps fluid around the body, instead plants produce hormones to move throughout the plant body to affect plant growth. There is a myth that plant growth hormones are bad. Its not the hormones that are bad but the inadequate know-how in handling and applying them.
There are 5 main Hormones in any plant. 3 of them are classified as growth hormones (Cytokinin, Auxin & Gibberellic Acid) and 2 as stress hormones (Ethylene & Abscisic Acid).
The function of hormones includes but are not limited to the following:
- Cytokinin :
This is known as ‘the dispatcher hormone’. It is known to control cell division and differentiation. It is primarily produced in the root tip meristematic tissue and acts to reduce senescence (aging) of the plant.
- Auxin:
This hormone activates and directs new cell division and food movement within the plant. It is produced in the new apical meristem tissue in the leaves. As auxin levels increases in the plant, increased levels of auxin transported to the roots tends to hinder cell division in the roots causing loss of root vigor which causes senescence to start.
- Gibberellic Acid:
A crop produces GA to encourage cells to size and elongate. It is normally stored in the nodes of a crop where it increases cell sizing & the reproduction of the buds that occur from the nodes. it reduces ripening and keeps plant tissue more youthful and vigorous as well as promotes germination of the seed.
- Ethylene :
Normal Ethylene: Helps with the movement of auxin from various cells within the crop. This is the hormone that signals reproductive maturity and initiates flowering and fruiting. It encourages an increase in ABA to drive plant tissue (seed, fruit, & storage tissue) into dormancy, which results in better storage shelf life of the harvested plants.
Stress Ethylene This plant growth hormone is secreted under stress conditions as a signal for plants to synthesise protective proteins to help overcome moderate stress. If the levels are not controlled under stress conditions, it will cause premature ripening and death.
- Abscisic Acid:
This hormone promotes ripening & seed dormancy. It is responsible for cell maturity and the termination of cell growth. It is made primarily in the roots and moves rapidly up to the shoots under any kind of stress
This brief description of the five major plant hormones shows just how important plant hormones are to plant health and growth. As growers work to maximise their crops yield potential, understanding the role of plant hormones is crucial.
Managing plant hormones along with the right customised foliar formulation can have a huge effect on crop yields. Hopefully you found this post helpful. If you want to know more about your crop nutrient needs, contact us – we’d love to chat!
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Macro – does not mean more important. Think of macro and micro nutrients as the ‘food’ and ‘multivitamins’ respectively that the plant needs to grow. As humans, we need adequate amount of food to help with our metabolic processes. The multivitamins are important as well. Plants are like humans in this regard. Macro nutrients are divided into primary macro-nutrients (nitrogen, phosphorus, and potassium) and secondary macro-nutrients (calcium, magnesium, and sulfur). Primary macro-nutrients are needed in larger quantities than secondary macro-nutrients.
Micro-nutrients such as zinc, iron, manganese, copper, boron, molybdenum, and chlorine are also required by plants but in relatively smaller quantities compared to macro-nutrients. How small is small?
Although plants need more macro-nutrients than they do micro-nutrients, that doesn’t mean that one is more important than the other. The “Law of the Minimum” tells us that the highest yield a grower will get is based on the lowest level of a required nutrient. If the soil is deficient in any macro or micro nutrient, the yield will be limited to the lowest level of that nutrient. Therefore, Balance is key!!!
Imbalance in macro and micro levels doesn’t only lead to the crop not maximising its yield potential but also to soil borne disease and weeds. Sounds familiar? What if that stubborn weeds on your farm can be eradicated by the simplest of methods? Example; did you know that the Canadian thistle thrives better on soils that have low calcium? The importance of nutrient balancing should never be over looked.
More so, it is important to note that Micros can assist with the uptake of macro by activating the plants’ transportation system. Calcium, silicon and Boron play important roles in this regard. Macro and micro nutrients are co-factors that also helps with the plant growth hormone activities. To build bushels, there must be balance in the co-factors and plant hormones at every stage of the crops grow cycle. Nutrient balancing will lead to healthier crops which will be able to withstand pest and disease pressure. Perhaps we should start focusing on improving nutrient uptake efficiency by balancing macro and micro nutrients in our protocols?
Hopefully you found this post helpful. If you want to know more about your crop nutrient needs, contact us – we’d love to chat!
