In the preceding 10 , the interest in light-emitting diode lighting in glasshouse horticulture has increase considerably , due to the depleted electrical energy consumption and reduced warmth cargo compare to HPS lighting . Another reward LEDs go is the alternative to create a crop specific “ tailor - made " light spectrum .
Far - red lightThere is already some experience in the cultivation of chrysanthemum under LED firing , but the question remains which light spectrum should be selected when a raiser needs to make decisions on investments in LED lighting . An important doubt hereby is whether or not far - red light should be added to the spectrum . The results of experiments and tests in commercial recitation are not always unequivocal . In some cases adding far - cerise light has no ( positive ) outcome , sometimes it does . The effect that were report relate to extension , bud time out in the lower part of the canopy , root , and a shorter clock time until flowering ( “ chemical reaction time " ) .
Far - red sparkle ( 700 - 800 nm ) is not visible to the human heart , and fall outside the photosynthetically alive radiotherapy ( PAR light ) , of 400 - 700 micromillimetre . However , far - reddish light is very crucial in a number of works processes such as elongation , branching and flowering , which are controlled by the ratio between red and far - red light . Well - known examples of applications of far - cerise light in glasshouse polish are the use of incandescent lamps in strawberry mark for the elongation of peducles , and in cucumber to meliorate leaf computer architecture and fruit output .
so as to be capable to answer the question about the applications programme of far - red light in an LED light spectrum for chrysanthemum , a test was recently started within the project “ precede light in sunshine " finance by Kas als Energiebron . In this spectrum trial , four chrysanthemum change are grown under full - LED , in which the top visible radiation accounts for approximately 80 % of the calorie-free sum , and the sunlight around 20 % . The light treatments that are applied disagree in the proportion of far - red light source and the time of twenty-four hour period at which this far - red visible radiation is given . The light-emitting diode brightness level intensity level use is 190 µmol / m2 / s , which includes far - cerise sparkle .
The next stepsDuring the trial , craw development is monitored , and stem length and easy interception are measured . In the average destructive measurement and the final harvest , elaborate plant life measure will be taken on stem duration and weight , figure of leaves / internodes . The prison term until anthesis will be determined per form per treatment . These results will help to make decisions on the software of the most suited light spectrum , to be able-bodied to take the next dance step towards a full - run cultivation system for chrysanthemum.
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