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View Full Version : Research on LIGHTINIG .your opinions



cture
11-30-2006, 12:49 AM
Please read carefully before answering.
Started to grow recently (week 1), started to research scientific literature aboout growing. The aim: perfect plant.
Sat in the library and
Resuts of my research are following.
Red light with a maximum of radiation of 640-670 nanometers promotes intensive growth of leaves and axial bodies. On red light we observed the highest growth effect, stimulated by photoreceptor of red light - fitochrome. Blue light slows down growth of a stalk and the area of leaves that leads to formation of plants with low productive efficiency.
In green area of a spectrum (a maximum of radiation of 520-550 nanometers) were formed thin leaves with smaller number of cells of chloroplast and with the lowest rate of photosynthesis per area of the leaf, but with the highest phtosynthesis in account to chloroplast.
Thus, each of three basic areas of PAR (dark blue, green and red), taken separately, is poorly suitable for cultivation of plants and only the radiation taken in a certain parity of energy on all spectrum, can provide cultivation of high-grade plants. Strong infringement of this parity, for example, when plants receive a maximum of radiation only in dark blue area of a spectrum, leads to formation of undersized plants with high photosynthesis, but low productive efficiency. Strong skew on a spectrum in red area of a spectrum, on the contrary, leads to excessive growth of vegetative bodies (leafes) To the detriment of generative( BUUUUDDDS).
Thus, spectral structure of light as well as its intensity, is strong morfogenic factor regulating growth, vegitative and photosynthetic reactions in system of the whole plant. Thus it is desirable to have a following parity of energy on a spectrum of PAR in lamps for many agricultural plants: 25-30 %- blue area (380-490 nanometers), 20 % in green (490-590 nanometers) and 50 % - in red area (600-700 nanometers).
In these conditions photosynthesis was supported within all light day without midday depressions, daily consumption of CO2 was considerably above, than at solar illumination, photosynthesis and growth have been well balanced.

And my main problem: what light should I pick. HPS doesn't seems to meet requrements above, however they write that their par 360w out of 1000w bulb but in fact the parity of color in spectrum stated above isn't reached and is mostly intensive between green and red, the only thing is good in this lamp is lifetime.
Thinking of xenon lghtining.
Your opinions with well stated arguments are welcome.

cture
11-30-2006, 01:11 AM
A little more
1. Low intensity of PAR (minimally admissible) - a range of intensity at which growth of vegetative bodies occurs, but are not formed high-grade generative bodies (bud). Thus photosynthesis has low parameters. For photophilous plants it is intensity in a range 15-30 w/m^2
2. Optimum intensity PAR - a range of intensities at which the maximal accumulation of a biomass in unit of time is observed. Thus The part of a useful part of a crop to sheathe makes 50-70 %. Photosynthesis and growth are well balanced. For photophilous plants it is a range of PAR 150-220 w/m^2
3. Sating intensity of PAR - the maximal intensity of light at which the output of photosynthesis on a plateau of light saturation is reached, ie maximal photosynthesis. Thus, growth inhibition of a stalk and other axial bodies is observed - plants get the undersized form. The part of a useful part of a crop to sheathe is high, but the general biomass collects less, than at optimum intensity as growth is braked (400 PAR w/m^2 and more), requres tripple nutrition feeding

cture
11-30-2006, 01:15 AM
And again.
500 w/m2 PAR = ~100 000 lux
Could be achieved by xenon lightining.
Any alternatives?