Hydroponic Trials Feedback
* (NB. Hydrosmart was formerly badged as Calclear technology, the original technology is now only available under the name Hydrosmart.)
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Suntec HYDROPONIC CONSULTANTS Hydroponics, Product Development Information, Contract Research Consultants |
Dr Lynette Morgan PhD Simon Lennard M.Hort.Sc P O Box 41 Tokomaru 5450 Manawatu New Zealand Phone/Fax 0064 6 3298041 NZ Mobile 0254 768 53 Email suntec@voyager.co.nz |
QUESTIONS AND ANSWERS ON THE EFFECTS OF CALCLEAR TREATMENT
Q1: How do the Calclear units work to lower the incidence of tipburn in hydroponically grown lettuce?
A: Tipburn is a browning and drying of the leaf margins, which often occurs as the heads reach harvest. This disorder is a calcium transport problem within the plant and occurs when the foliage is losing water into the air faster than the roots can take it up or, in high humidity and low water loss conditions when the transpiration stream in which the calcium is transported becomes restricted. The Calclear units can lower the severity and incidence of tipburn by having a beneficial effect on xylem conductance. The xylem are the vessels within the plants that carry the water and dissolved calcium to the leaf tips. This also resulted in higher levels of foliar calcium in the heads at the time of harvest in plants treated with the Calclear units compared to the untreated control plants. The Calclear units not only improve the uptake and transport of the calcium, but they also seem to improve its utilisation in plant cell development.
Q2: If tipburn is caused by low levels of calcium in the leaf margins, then why can't I just increase the levels of calcium in the nutrient solution to prevent tipburn?
A: The problem with tipburn is that it is a physiological disorder caused by low levels of calcium in the leaf tips, but this is not a result of a lack of calcium in the nutrient solution. Increasing the calcium, if it is already present in adequate quantities in the nutrient solution will have no effect if tipburn is occurring, as environmental and internal plant conditions are what causes the problem. It is the rate of transport of calcium through the xylem tissue that is important when conditions are conductive to tipburn. An increase in xylem tissue conductance has been found in plants grown with Calclear units, so this is what causes the lower tipburn incidence in crops treated with the conditioner units.
Q3: What plant processes do the Calclear units positively effect?
A: The evidence suggests that the Calclear units act to enhance xylem conductance thus allowing the plants to transpire more effectively and therefore moving more calcium into the leaf tips. There is also some evidence to suggest that the units can positively influence plant metabolism and they have been shown to reduce the bitter flavour component of lettuce leaves. The Calclear conditioner treated solution may work to some extent to reduce the polymerisation of glucose molecules into starch crystals, allowing a higher concentration of free sugars within the plant cells, therefore giving a better taste. Trials are currently under way to test this effect on tomato fruit with both compositional and sensory evaluation.
Q4: Will the Calclear units affect other hydroponic crops in a beneficial manner?
A: Since trials on lettuce have proven that the Calclear units increase conductance through the xylem and have the effect of raising calcium levels in plant tissue with plants under stress, it is quite likely that other crops may benefit in the same way. There are many calcium related disorders such as blossom end rot of tomatoes and peppers and bitter pit of apples that may respond to treatment with a Calclear unit. There may also be colour, yield, shelf life and flavour advantages to having nutrient solutions treated with a Calclear unit and trials are currently under way to quantify the benefits of the water conditioning units, on other plant species.
Q5: Do the units change the composition of the nutrient solution?
A: No. The Calclear unit will not change the amount of nutrient ions in your solution so you don't have to worry about adjusting your nutrient formula. What the conditioner units do is to prevent some of the salts in the solution from clumping together and forming crystals that would normally make them more difficult for the plant roots to take up. The strong flux field that the units generate in the nutrient supply pipe, modifies the calcium carbonate crystal nuclei in particular. Thus when the nutrients are unable to form crystalline salts with other elements, they may also be prevented from forming crystalline structures within the xylem allowing the plant to transpire more effectively.
Q6: Will I need to change the way I monitor and adjust the nutrient solution conductivity and pH?
A: No. The Calclear units will not cause drastic changes in pH and CF and you can carry on your normal monitoring and adjustment as usual.
View a report on the 2 year trials
View a full report on the effects published in Practical Hydroponics and Greenhouses magazine