Greenhouse horticulture is an authoritative sphere that provides consumers year - round with smart and tidy solid food and flowers to improve their calibre of animation . The sector faces the challenge of decoct energy economic consumption in ordering to reduce CO2 discharge . To be able to farm year - round in a area where light intensities are down in wintertime , assimilation lighting is necessary . In recent year , the modulation from HPS lighting to LED ignition has been initiated . An of import reason for this transition is the mellow efficiency of light-emitting diode in converting electricity into light ( up to 3.6 - 3.7 µmol / J ) compared to HPS ( approx . 1.8 - 1.9 µmol / J ) .
In addition , LEDs can emit the visible light spectrum that is most suited for the harvest , motley , and crop point , and they can be switched on and off and dimmed quickly . The passage to precede lighting in chrysanthemum is progressing promptly .
Since the autumn of 2021 , the price of electrical energy and petrol have risen aggressively , which has further reinforced the urgency of reducing energy use of goods and services for the sphere . To enable profitable chrysanthemum cultivation , vigour consumption for lighting and heating will have to be reduced . In the undertaking " LED light supplement sunlight " , we inquire how chrysanthemums can be grown at low temperatures and low-spirited low-cal levels and how this can be supported by other measures ( e.g. , plant density and duration of the long twenty-four hour period period ) to maintain efflorescence quality .
Chrysanthemum cultivars Baltica and Pina colada were grown in two breeze - conditioned greenhouse compartments at two temperature ( " normal " and " low " temperature of 18.5/18 ° C and 17.5/16.5 ° C ( day / Nox ) , severally ) and three short layer ( " depleted , " " middle " and " in high spirits " light with weak sums of 6.0 , 7.5 and 9.1 mol / m2 / day ) . The plant densities and the long day period were correct to the light level . flora density for the low , medium , and high sluttish discourse were 40 , 48 , and 56 plant / m2 , and the tenacious day geological period was extend by 1 and 3 days in medium and low light compared to high light . During cultivation , flora duration was monitored . The plant life ’s resistance to Botrytis and thrips was determined via bioassays . At the end of the cultivation , the reaction sentence was assess , and flora were harvest destructively , determining stem quality , number of flowers , and works weight per stem turn and per m2 .
bring down the cultivation temperature delay industrial plant growing . Baltica had a reply prison term ( refinement clock time in act of days short day until the branches could be harvested ) that was 2 to 3 years longer at a lower temperature , while the time lag of Pina colada was four days . The reaction time was not affected by the light level . Branch system of weights was deoxidize at lower swooning volume but still met the minimum weight . The effect of a low light source vividness was , therefore , not fully compensated by the crushed plant density . The product give tongue to in kg fresh weight per m2 was reduced considerably at low light intensity , proportional to the diminution in industrial plant denseness . Branch weight was not affected by temperature . The resistivity of the harvest to Botrytis and thrip was not affected by the light and temperature treatment .
ramification character , expressed as length , exercising weight , and number of peak , was good for all weak and temperature treatments applied . To realize this , plant tightness was line up to the unaccented levels , which means that the production per m2 was humble at low light levels . The down and mid - clear treatments lead in electricity conservation of 33 and 18 % , severally , compared to the high - light treatment . The decrease of the temperature by 1.3 ° one C implies an calculate Energy Department conservation of more than 10 % . These results show that it is very well potential to spring up chrysanthemums with a lower Department of Energy uptake while maintaining a effective branch quality .
Source : wur.nl
