Patent Abstract:
a process for photomorphogenically enhancing plants is presented wherein a natural or artificial light source emits light through a transmittive material . the material is optionally borosilicate glass with a steep edge situation at or near 280 nm so as to selectively filter out light in the uvc or low uvb regions . the glass allows high transmissibility such that as much as 98 % of all light at or above the edge situation passes thorough the material . the percent transmission and edge situation may be defined by glass thickness or by combining multiple types of glass . the light is then contacted with a plant whereby a photomorphogenic response is elicited .

Detailed Description:
the instant invention has utility in increasing the economic benefit , output and desirability of plants grown in artificial lighting conditions and to benefit such plants . the instant invention is generally related to a container , a glasshouse , or other system for the growing of plants or other crops . in a preferred embodiment an artificial light source is oriented such that illumination is transmitted through a solid or semi - solid light transmissive material and subsequently contacts plants oriented on the opposite side of the transmissive material as the illumination source . a physical system suitable for use in the instant invention is optionally a wall structure constructed of light transmissive material that allows the passage of light sufficient to promote growth of the biological material stored in a reservoir defined by the wall structure itself . in a preferred embodiment the structure is a glasshouse or other greenhouse type structure . the glasshouse is optionally a small desktop container . it is appreciated that the glasshouse is of any suitable size for the intended use such as large scale crop production in fluid , soil or other solid media , or for a single plant as in a home growing situation . in a preferred embodiment the glasshouse is used for growing ornamental flowers or other home or commercial use plants suitable for a horticulture business . it is desirable that the transmissibility of the wall material at selected light wavelengths is kept at a maximum . in a preferred embodiment borosilicate glass is used as a transmissive material . non - limiting examples of glass include borosilicate or flint glass , soda lime glass , and quartz . preferably the light transmissive material not only allows passage of sunlight but is transparent to promote full passage of all light necessary to support growth including that in the uvb , uva , photosynthetically active region , and infrared regions . translucent materials are optionally used to screen out certain wavelengths or light intensities depending on factors and needs of the biological material or the need to reduce accumulation of heat in the structure . the transmissive material is preferably a borosilicate glass with optical and physical properties including 60 % to 70 % by weight silicon dioxide , 10 % to 15 % by weight b 2 o 3 , 5 % to 15 % by weight na 2 o , 5 % to 10 % by weight k 2 o , 0 . 1 % to 1 % by weight cao , 0 . 5 % to 3 % by weight bao , 0 % to 5 % by weight dilithium oxide , 0 % to 2 % titanium dioxide , 0 % to 25 % by weight zno , and 0 % to 0 . 5 % by weight sb 2 o 3 , and normal refining agents . it is appreciated that the inclusion of oxides of ti , zn , or sb are effective in limiting the amount of uvc transmitted while still passing a limited quantity of uvb needed to promote growth . in a preferred embodiment borosilicate glass with a defined edge situation is used as the wall structure . the edge situation or edge wavelength corresponds to half the pure transmission maximum value between the blocking and the permeable range . an illustrative example of an optical borosilicate glass operable in the instant invention is defined in u . s . patent application publication 2004 / 0132604 a1 . the desired spectral characteristics of the borosilicate glass are defined by a steep uv edge in the uv range corresponding to the application purpose , as shown in fig1 . in a preferred embodiment , the light transmissive material has a transmissivity with a point of inflection between 280 and 305 nm and located in the uvb range so as to transmit the uva and photosynthetically active visible wavelengths while limiting the amount of uvc transmitted to a plant . a point of inflection in the transmission spectrum as used herein is defined as a point where the double derivative spectrum is zero and bounded by non - zero values . the point of inflection is located central to a sigmoid curve of transmissivity as shown for example in fig1 - 3 at 285 nm , 307 nm , and 298 nm , respectively . a preferred range for a spectral point of inflection is 285 and 310 nm . this sharp edge situation uvc cutoff achievable by varying the content of titanium dioxide or zinc oxide in the glass system . borosilicate glass composed simply of normal refining agents contains high levels of transmissibility throughout the ir and visible spectrum with no uva blockage , little uvb blockage , and total uvc blockage . thus , doping of the glass with material such as titanium dioxide creates a desired steep edge situation at a desired wavelength . preferably the borosilicate glass has a point of inflection between 280 and 320 nm . preferably the transmissive material has a steep cutoff at the desired uvb wavelength and the highest possible transmittance of light in the remaining range of the spectrum such as the uva , visible , and infrared spectral regions . a preferred material has high temporal stability of the spectral transmission characteristics such that temporal transmittance is not altered over the course of time . optionally , the glass is tempered . additionally , material suitable in the instant invention optionally has high mechanical stability such that it can define a wall and can resist weathering conditions and the weight of material such as snow or resist damage from projectiles . finally a material suitable in the instant invention is optionally available in large sheets such that construction of large glasshouses is easily obtainable . it is appreciated that large continuous films , liquid sprays or other treatments , are similarly suitable in the instant invention . transmissive filtering materials are preferably able to withstand high intensity uvb radiation . borosilicate glass thickness used in a preferred embodiment optionally regulates the level of transmittance . in a non - limiting example the thinner the glass material the more light is transmitted . preferably the glass material allows transmission of greater than 50 % of light with a wavelength at or above the edge situation . more preferably light transmission at or above the edge situation is between 90 and 95 %. most preferably the light transmission levels are greater than 95 % at or above the edge situation with an optimal level of 98 % or greater light transmission at or above the edge situation . glass materials as thin as 1 to 2 mm thick are the most beneficial in providing light transmissibility . a 1 mm thick borosilicate glass will block all uvb from a 1 watt lamp and virtually none from a 1000 watt lamp . thus , the glass thickness is preferably chosen with relation to the intensity of the chosen light source . preferably the borosilicate glass used is between 1 and 10 mm thick , more preferably between 2 and 5 mm thick . it is appreciated that glass with thickness parameters outside these preferred ranges is optionally employed in the instant invention . optionally multiple glass types , compositions , and thicknesses are combined in a single wall situation . for example , glass with greater thickness is optionally employed in regions of high light availability or where the structural integrity of the glasshouse is of paramount concern such as in geographic regions that receive large amounts of snow . glasshouses suitable for use in the instant invention optionally contain thicker glass on some portions of the ceiling panel and thinner glass structures on other portions of the ceiling or wall . illumination is optionally adjusted such that higher uv emitting lights are used on wall portions with thicker glass and lower energy uv light emitting bulbs are used where thinner of the glass is used . optionally the glass panel is movable to rotate or otherwise alter position with adjusting solar light source position . in maximizing the strength of the structure and simultaneously reducing the amount of energy used , numerous illuminating sources are optionally employed in the instant invention such as sunlight or artificial sources . artificial light sources optionally include high intensity discharge ( hid ) lights selected to emit visible light , ultraviolet radiation , or infrared radiation . preferably , maximum uv radiation emitted from hid lamps is preserved by the chosen glass material . fluorescent bulbs are optionally employed to selectively emit various wavelengths of ultraviolet radiation such as uvb - 313 fluorescent lamps , as well as metal halide ( mh ) lamps or high pressure sodium ( hps ) bulbs . bulbs optionally employed include mh bulbs suitable for emitting wavelengths between 400 and 500 nm and used for increasing vegetative growth or hps bulbs suitable for emission of longer wavelengths such as between 500 and 700 nm which are used for voluminous flower production . lamps are optionally used individually or in combination to provide or supplement ultraviolet light . in a preferred embodiment the light transmissive material totally surrounds the lamp structure such that each lamp structure individually comprises an illuminating unit . more preferably the light source is oriented above or to the side of the biological material . numerous illuminating units or illuminating sources are optionally employed depending on the required light intensity or spectral characteristics of the light to be illuminated on the biological material . different light sources are optionally employed at different locations around the biological material . in a non - limiting example , the light sources are more uv emitting above the plant with less uv emitting light sources to the side of the plants to mimic the movement of the sun . optionally , the light sources are varied at different locations in the glasshouse . in a non - limiting example , more intense uv emitting lights are optionally placed overhead whereas lower emitting light sources are placed lower to the horizon . each of these light sources are optionally illuminated at different times to mimic movement of the sun . the inventive process optionally alters stress responses or photomorphogenic properties of the biological material . the photomorphogenic properties altered by the chosen light spectrum are optionally defense mechanisms against a pathogen attack , increased levels of uv activating genes , modified gene expression , thickening fruit skin , altering fruit flavor characteristics , increased production of flavonoids , increased fungal resistance , enhancing pigmentation , increased pigment production , essential oil output , resin output , decreased stem elongation , increased radial growth of flowers , altering architectural properties , post harvestability , increases or decreases in flower numbers , increases in thricome density , decreases in leaf area , altering production of terpenoid , alkaloid , phenolpropanoid or other economically valuable compounds such as pharmaceutics . secondary metabolites produced by the altered photomorphogenic characteristics in the instant invention optionally include products such as dyes , polymers , fibers , glues , oils , waxes , flavors , perfumes , and drugs . the present invention is further illustrated with respect to the following non - limiting examples . low expansion borosilicate glass suitable in the instant invention is commercially available ( pyrex 7740 borosilicate glass , corning , inc .). this glass has the spectral profile as shown in fig1 . this glass is manufactured in sheets with a low coefficient of expansion providing mechanical stability . this material is suitable for manufacture into sheets for glasshouse or other biological material growth . another material suitable in the instant invention is zinc titania glass ( corning , inc .). the transmission profile of this glass is shown in fig2 . this glass is manufactured in small sheets at 1 mm thickness . this glass or other suitable glasses are optionally stabilized by a transparent or metal mesh to provide mechanical stability to the glass while maintaining the desired optical transmission and full light pass characteristics desired . in this fashion large sheets are produced that can be installed on a glasshouse . alternatively , zinc titania or other glass is used in combination with soda lime glass commonly used for plate glass building purposes . a typical spectral profile of soda lime glass from corning , inc . is shown in fig3 . a transmissive material with soda lime glass placed on top of a borosilicate glass will protect the borosilicate glass from solarization increasing the useful life of the transmissive material . ( dohring , t , 1996 .) borosilicate glass ( pyrex 7740 ) panes of 2 mm thickness used as high transmissibility , steep edge situation filters are placed in an aluminum frame . a combination array of different lamps including metal halide , quartz - halogen , blue fluorescent , and uv - b fluorescent lamps to provide the uvb portion of the spectrum ( seckmeyer , g ., and payer , h ., j photochem photobiol , 1993 ; 21 : 175 - 81 ) are positioned opposite the inventive glass panes from soil containing a mixture of levington compost b2 and perliet ( 3 : 2 ). ocimum basilicum l . is grown in the soil and exposed to illuminating conditions for 14 hours per day and cycled through darkness for the remaining 10 hours per day against a like control receiving no uv irradiation . after growth for 15 days , leaves are analyzed for anatomical characterization and quantitation of essential oil from developing and mature leaves as described by ioannidis et al ., 2002 . uvb treatment leads to photomorphogenically increased essential oil production in the leaves of both developing and mature plants , with a greater increase in the developing leaves . leaf gland numbers are not increased . however , increases in oil gland volume are increased and are 35 % greater in mature leaves and 20 % greater in developing leaves . importantly , the fragrance of the leaves is pleasantly increased . this increase in fragrance is attributable to increases in the number of broken oil sacks in these plants where the rate of breakage is around 40 - 45 %. soybeans are grown from seed under light as in example 2 at 15 kj / m 2 / day uvb radiation and in standard greenhouse environmental conditions of temperature and humidity against a like uv irradiation free control . these photomorphogenic soybeans require much lower soil moisture levels as the root structure is enhanced under these growth conditions relative to controls . the photomorphogenic root to shoot ratio is significantly improved providing greater soil penetration and plant - soil interaction which in turn requires reduced water input to maintain growth parameters . these photomorphogenic plants also show increased dry weight mainly attributable to increase root mass . further , the photomorphogenic relative leaf area ratio decreases in these plants . the lower leaf area is responsible for limiting transpiration loss . however , the photosynthetic quantum efficiency , phytochrome photostationary state , and phytochrome cycling rate remain unchanged in soybeans grown under the inventive conditions . finally , stomatal density is reduced further leading to increased water use efficiency . thus , growing soybeans under the inventive conditions produces plants that possess improved water retention , reduced irrigation requirements and also have similar photosynthetic capacity as plants grown otherwise indicating a greatly improved overall growth profile . wild mint ( mentha spicata ) is grown in soil in a glasshouse constructed of borosilicate glass made from 69 . 98 % ( by weight ) sio 2 , 11 . 19 % b 2 o 3 , 9 . 49 % na 2 o , 7 . 29 % k 2 o , 0 . 2 % cao , 1 . 35 % bao , 0 . 2 % tio 2 , 0 . 3 % sb 2 o 3 , and expected refining agents as described . us 2004 / 0132604 a1 . illumination is as in example 1 . no changes are observed in photosynthetic capacity , total stem length , chlorophyll content , or photochemical efficiency of photosystem ii . however , leaf mass is increased although no change in leaf area is observed . importantly , seed yield is improved with yields as much as 100 % higher . the increased seed production drastically improves replanting procedures and field success . the perennial herb silene vulgaris was analyzed in a glasshouse under light conditions as in example 1 using glass with light transmission down to 290 nm . light intensity is 16 . 2 kj / m 2 uvb radiation levels with full uva and par light illumination . illumination is maintained for 51 days . these herbs produce much higher numbers of seed producing flowers than plants grown in traditional glasshouse lighting conditions . further , the number of infertile flowers is decreased using the inventive grow lighting process . the seeds produced from the plants grown in the inventive conditions show unchanged germination rates . salvia splendens is grown under conditions of example 1 . these plants demonstrate a more compact stature and improved resistance to handling . these properties greatly improve cultivation and storage capacity improving transport capacity . references cited herein are indicative of the level of skill in the art to which the invention pertains . these references are hereby incorporated by reference to the same extent as if each individual reference was explicitly and individually incorporated herein . 1 . allen , d . j ., nogues , s ., baker , n . r . 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( 1992 ) changes in mrna levels and polypeptide subunits of ribulose 1 : 5 - bisphosphate carboxylase in response to supplementary ultraviolet - b radiation . plant cell environ 15 : 91 - 98 . 57 . karabourniotis , g ., k . papadopoulos , m . papamarkou and y . manetas ( 1992 ) ultraviolet - b radiation absorbing capacity of leaf hairs . physiol . plant 86 , 414 - 418 . 58 . karousou , r ., grammatikopoulos , g ., lanaras , t ., manetas , y ., kokkini , s . 1998 . effects of enhanced uv - b radiation on mentha spicata essential oil . phytochemistry 49 : 2273 - 2277 . the foregoing description is illustrative of particular embodiments of the invention , but is not meant to be a limitation upon the practice thereof . the following claims , including all equivalents thereof , are intended to define the scope of the invention .