Abstract:
For indoor mushroom cultivation, a method of irrigating the mushrooms includes drip irrigation pipes in the bed. The drip irrigation pipes can be disposed in a casing layer that overlies a substrate layer, and irrigation can be according to measurements taken in the environment outside of the bed.

Description:
TECHNICAL FIELD 
       [0001]    Embodiments of the invention relate to methods of indoor mushroom cultivation, growing or production. 
       BACKGROUND 
       [0002]    Indoor commercial production of mushrooms allows for tight regulation of growing conditions such as air, temperature and relative humidity while substantially eliminating contaminants and pests. This technique typically employs trays or beds for growing the mushrooms which provides the advantages of scalability and easier harvesting. The trays or beds typically include a substrate such as compost and a casing soil that is disposed above the substrate. 
         [0003]    The casing soil serves as a water reservoir for the mushrooms and a typical watering technique employed includes spraying the beds or trays from above. While using such a spraying technique it is normally required during certain stages of mushroom growth to stop the watering in order to limit the sprayed water from coming into contact with the developing mushrooms. Wet mushrooms may also enhance occurrence of mushroom diseases such as bacterial blotch. At this time, since watering is halted, the water content in the casing and substrate may decrease to below optimal levels. 
         [0004]    PCT Publication No. WO 2006/090965 describes a certain type of drip irrigation tube with scar cuts that are formed on rubber dripping elements. These scars are prevented from direct exposure with the culture medium layer in order to prevent mycelia from being coated in these scar cuts which will clog the exit for water. The ability to effectively add water to the casing layer without wetting the mushrooms may be seen to have the advantages of: adding the needed water to the mushrooms during the entire crop cycle, minimizing the incidence of mushroom diseases, enhancing mushroom quality, and reducing costs of casing and energy. 
       SUMMARY 
       [0005]    The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. 
         [0006]    The present invention is expressed by the features of the independent claims and aspects. The dependent claims and aspects refer to preferred embodiments. 
         [0007]    Embodiments of the present invention relate to methods for irrigation and cultivating mushrooms using drip irrigation pipes in an indoor environment. By irrigating mushroom with drip pipes as opposed to conventional irrigation with sprinklers, damage to mushrooms may be avoided or limited and irrigation may be performed during longer and more regular intervals. 
         [0008]    In one form of the present invention the method may comprise steps of providing a horizontally extending bed in which a substrate layer and a casing layer that is disposed over the substrate layer are provided. And, the drip irrigation pipes are disposed in the bed preferably in the casing layer. 
         [0009]    In one aspect of the present invention irrigation via the drip irrigation pipes is affected by measurements of water evaporation in the indoor environment outside of the bed. These measurements may derive a value M which may be taken periodically. Possibly these measurements can be taken every N hours with N being either a fraction smaller than 1 hour or any value larger than 1 hour. 
         [0010]    In various forms of the present invention from the measurements of water evaporation an amount of liquid to be irrigated can be derived and irrigated preferably in pulses to the bed and/or mushrooms. 
         [0011]    In one aspect of the present invention the irrigated liquid may be used to maintain a generally constant liquid content in the casing layer while gradually decreasing the liquid content in the substrate preferably compost layer. Possibly relative short liquid pulses optionally with long intervals between pulses may result in an irrigation procedure in which liquid is maintained more in the casing layer and seeps less towards the substrate later below the casing layer. Longer irrigation pulses optionally with shorter intervals between pulses may result in more liquid that is irrigated to the bed that then seeps down towards the substrate layer. Since the preferable compost material of the substrate may physically change over time resulting in its reduced liquid holding capacity—it may be preferable as irrigation proceeds to limit the amount of liquid reaching the substrate layer. And this may be achieved by changing pulse length and time intervals between pulses. 
         [0012]    Further aspects of the present invention will be apparent also from the following numbered aspects:
   1. A method of indoor mushroom cultivation comprising the steps of:
       providing a horizontally extending bed comprising a substrate layer and a casing layer that is disposed over the substrate layer, and   providing drip irrigation pipes that are disposed in the casing layer.   
       2. The method according to aspect 1, wherein the disposing of the drip irrigation pipes in the casing layer is performed after the casing layer has been disposed over the substrate layer.   3. The method according to aspect 1 or 2, wherein the disposing of the drip irrigation pipes in the casing layer is by urging the drip irrigation pipes into the casing layer.   4. The method according to aspect 3, and comprising a device for urging the drip irrigation pipes into the casing layer, the device being adapted to move in a horizontal direction above the casing layer.   5. The method according to aspect 4, wherein as the device moves above a given portion of the casing layer it urges at least some of the drip irrigation pipes to be disposed into that given portion. In one form this may be performed by providing the device with a slanted sleeve with one upper end located above the bed and a second lower end located within the bed preferable opening into the casing layer. A drip irrigation pipe threaded though the sleeve with its leading end projecting out beyond the lower end of the sleeve, can then be urged into the bed by moving the device horizontally along the bed towards one end of the bed while keeping the pipe&#39;s leading end fixed in place to and/or adjacent e.g. another end of the bed.   6. The method according to anyone of the preceding aspects, wherein the drip irrigation pipes are disposed in the casing layer such that their apertures for discharging liquid face substantially the same given direction. This may assist in more accurately controlling where irrigation is provided and reduce possibility of over irrigation that may harm the crop.   7. The method according to aspect 6, wherein the given direction is up.   8. The method according to anyone of aspects 1 to 7, and further comprising a step of irrigating liquid using the disposed drip irrigation pipes, and wherein an amount A of liquid irrigated is determined according to parameters monitored in the indoor environment outside of the bed and parameters monitored in the bed.   9. The method according to anyone of aspect 8, wherein the amount A of liquid irrigated is irrigated in pulses.   10. The method according to aspect 8, wherein the parameters monitored in the indoor environment outside of the bed are associated to at least one of: a bellow communicating air to and from the indoor environment, a shutter controlling communication of air to and from the indoor environment, a temperature gauge measuring the temperature within the indoor environment outside of the bed.   11. The method according to aspects 8 or 9, wherein the parameters monitored in the bed are at least one of: a moisture sensor in the casing layer, a moisture sensor in the substrate layer, a tensiometer in the casing layer, a tensiometer in the substrate layer.   12. The method according anyone of aspects 8 to 11, wherein the liquid irrigated comprises water and/or nutrient amendments.   13. The method according anyone of aspects 8 to 12, wherein the drip irrigation pipes comprise at each aperture in a respective pipe a drip emitter through which liquid passes before being discharged out of the pipe.   14. The method according to aspect 13, wherein each one of the drip emitters has a discharge-pressure threshold greater than zero so that only when local liquid pressure at a location of an emitter in the pipe is greater than zero the emitter will discharge liquid from the pipe.   15. The method according to aspect 14, wherein each one of the drip emitters is a regulated drip emitter that has a discharge rate of liquid out of the pipe that is substantially independent of variations in local liquid pressure at the location of the emitter in the pipe.   16. The method according to aspect 15, wherein the discharge rate of liquid out of the each drip emitter is lower than 1 liter/hour.   17. The method according to aspect 16, wherein the discharge rate of liquid out of each drip emitter is substantiality 0.7 liter/hour.   18. The method according to anyone of aspects 1 to 7, and further comprising a step of irrigating liquid using the disposed drip irrigation pipes, and wherein an amount A of liquid irrigated is determined according to a measure M taken of water evaporation in the indoor environment outside of the bed.   19. The method according to aspect 18, wherein the measure of water evaporation in the indoor environment outside of the bed is taken every N hours.   20. The method according to aspect 19, wherein the determination of the amount A of liquid irrigated is according to A=M×N×F, wherein F is a parameter determined according to the value of M.   21. The method according to aspect 20, wherein K is a threshold parameter of water evaporation, Fu is a first value for F and Fd is a second value for F that is smaller than Fu, and if M &gt;K then F =Fu and otherwise F =Fd.   22. The method according to aspect 21, wherein when M and K are measured in gram to square meter of water.   23. The method according to anyone of aspects 18 to 22, wherein the amount A of liquid irrigated is irrigated in pulses.   24. The method according to anyone of the preceding aspects, wherein the substrate layer comprises compost and the casing layer comprises peat moss and limestone.   25. A method of indoor mushroom cultivation comprising the steps of:
       providing a horizontally extending bed comprising a substrate layer and a casing layer that is disposed over the substrate layer,   providing drip irrigation pipes that are disposed in the bed, and   irrigating liquid using the disposed drip irrigation pipes, wherein an amount A of liquid irrigated is determined according to a measure M taken of water evaporation in the indoor environment outside of the bed.   
       26. The method according to aspect 25, wherein the measure of water evaporation in the indoor environment outside of the bed is taken every N hours.   27. The method according to aspect 26, wherein the determination of the amount A of liquid irrigated is according to A=M×N×F, wherein F is a parameter determined according to the value of M.   28. The method according to aspect 27, wherein K is a threshold parameter of water evaporation, Fu is a first value for F and Fd is a second value for F that is smaller than Fu, and if M&gt;K then F=Fu and otherwise F=Fd.   29. The method according to aspect 28, wherein when M and K are measured in gram to square meter of water.   30. The method according to anyone of aspects 25 to 29, wherein the amount A of liquid irrigated is irrigated in pulses. In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the figures and by study of the following detailed descriptions.   
 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0048]    Exemplary embodiments are illustrated in referenced figures. It is intended that the embodiments and figures disclosed herein are to be considered illustrative, rather than restrictive. The invention, however, both as to organization and method of operation, together with objects, features, and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanying figures, in which: 
           [0049]      FIGS. 1 and 2  show side views of a bed for mushroom cultivation during optional steps of disposal of drip irrigation pipes therein in accordance with an embodiment of the present invention; 
           [0050]      FIG. 3  shows a flow diagram of an algorithm for controlling irrigation of the bed in accordance with an embodiment of the present invention; and 
           [0051]      FIG. 4  shows graphs for substrate and casing layers optimal water content during the mushroom growth cycle when irrigation can be provided. 
       
    
    
       [0052]    It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated within the figures to indicate like elements. 
       DETAILED DESCRIPTION 
       [0053]    Attention is first drawn to  FIGS. 1 and 2 . In an embodiment of the present invention, an indoor commercial bed  10  for mushroom cultivation, growth and/or production; may include a tray (not shown) upon which a substrate layer  12  may be laid. Substrate layer  12  optionally consists of compost, and a casing layer  14  optionally consisting of peat moss and/or limestone may be laid upon it. Within the casing layer  14  drip irrigation pipes  16  may be disposed for irrigating mushrooms such as White Button mushrooms/Champignon and Portobello (scientifically named  Agaricus bisporus ),  Agaricus blazei, Lepista nuda,  or the like. 
         [0054]    Typical phases of mushroom cultivation may be defined as: Phase I (composting), Phase II (pasteurization and conditioning), Phase III (Spawning and mycelium growth), Casing, Pinning and harvest. The casing phase is when casing layer  14  is laid upon substrate  12  and after that the irrigation pipes  16  can be disposed into the casing layer  14 . Irrigation from that point can take place during the entire crop cycle, especially during pinning before the first flush (i.e. harvest of mushrooms) and between flushes when spray irrigation is typically avoided. The irrigation can include water and nutrient-amendments. 
         [0055]    For the disposal of the drip irrigation pipes  16  into the casing layer  14  a mechanical device  18  that travels above the bed  10  may be used. Device  18  can be used optionally, by traveling in a horizontal direction H 1 , for spreading the drip pipes  16  upon the bed  10  ( FIG. 1 ), and then in an opposing second horizontal direction H 2 , for disposing the drip pipes  16  into casing later  14 . An optional roller  17  that trails after device  18  as it disposes the drip pipes into the casing layer can be used to slightly compress the casing layer back into place where it was before the insertion of the pipes ( FIG. 2 ). 
         [0056]    In some embodiments of the invention, provision of irrigation to the bed by an irrigation system including the drip irrigation pipes  16  may be controlled in accordance with an algorithm  20  having a flow diagram similar to that shown in  FIG. 3 . The flow diagram delineates an optionally diurnal water provision cycle in which the irrigation system provides pulses of water to the bed. 
         [0057]    In a block  22 , optionally values for parameters that control the liquid provision cycle: Tcal, K, Fu and Fd can be determined by optionally being manually inputted by a grower using the irrigation system or his advisor. Tcal is a time during the diurnal cycle at which the irrigation system acquires a measure M of water evaporation in the indoor environment outside of the bed. K is a threshold value of water evaporation, and Fu is a factor used when M is greater than K and Fd is a factor used when M is not greater than K. 
         [0058]    In step  24  algorithm  20  checks a system clock (not shown) to acquire a reading of the time, “Tclock”. In a decision block  26  the time Tclock is checked to see if it is about equal to Tcal. If it is not, then the algorithm returns to block  24  to acquire a new reading for Tclock. If on the other hand Tclock is about equal to Tcal, algorithm  20  advances to a block  28  and acquires a reading of M of the water evaporation in the indoor environment outside of the bed. The algorithm then proceeds to decision block  30  to check if the acquired reading of M is greater than the threshold value K. If it is not, then the algorithm proceeds to block  32  to determine an amount A of water to be irrigated to the bed according to the equation A=M×Tcal×Fd. If on the other hand reading M is greater than the threshold value K then the algorithm proceeds to block  34  to determine the amount A of water to be irrigated to the bed according to the equation A=M×T cal×Fu. After either block  32  or  34  the algorithm proceeds to a block  36  where T clock is initialized to zero and from there the algorithm returns to decision block  26  to start a consecutive cycle that will lead to a consecutive irrigation cycle. 
         [0059]    The needed water amount A, may be divided into pulses of irrigation, that are provided at optionally given time intervals, until the amount A has been fed to the bed. 
         [0060]    By way of an example, a mushroom production bed may be sized and equipped such that it has: a width of 1.3 meters, a length of 24 meters, 8 drip lines that are disposed in parallel in the casing layer, with about 6 drip emitters per meter length having each a regulated discharge rate of 0.7 liter/hour. In such a setup, Tcal can initially be set to 5 hours, K can be equal to 40 gram/m 2 , Fu can be equal to 2 and Fd can be equal to 1.3. Following this example, If a measure M of the water evaporation in the indoor environment outside of the bed is equal to 50 gram/m̂2 then A=50×5×2=500 gram (i.e. 0.5 liter). This amount can be divided into pulses of 0.25 liter that are provided twice to the bed with a time difference of optionally 2 hours between the pulses. If on the other hand the measure M is equal to 30 gram/m̂2 then A=30×5×1.3=195 gram (i.e. about 0.2 liter), and this amount can optionally be divided into pulses of 0.1 liter that are provided twice to the bed with a time difference of 2 hours between the pulses. 
         [0061]    In experiments conducted by the inventors, it was demonstrated, that while typical casing layer thickness of 5.5 centimeters is used, when conventional spray irrigation is provided, with drip irrigation, it was possible to reduce the thickness of the casing layer to 3.2 centimeters, without harming the yield or the quality of the mushrooms. Attention is now drawn to  FIG. 4  that shows optimal water content graphs, for the substrate and casing layers that are applicable to certain conditions and certain bed configurations that were tested by the inventors. It has been found over a period of time, during which drip irrigation can be provided, that the casing layer&#39;s water content may optimally be kept during the entire crop cycle at the needed level. With respect to the substrate (i.e. compost), on the other hand, it has been found that its water content may optimally be reduced over the same period due to physical degradation that the substrate undergoes which decreases its water holding capacity. Optionally, for conditions in a bed to substantially follow this water content pattern, it has been found that shorter pulses of water tend to affect more the humidity of the casing layer while longer pulses affect also the humidity of the substrate (compost) layer. As a result, as the production of mushrooms progresses and time passes the average length of the pulses may become shorter in order to substantially maintain the same level of humidity in the casing while reducing water content of the compost. 
         [0062]    In the description and claims of the present application, each of the verbs, “comprise” “include” and “have”, and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements or parts of the subject or subjects of the verb. 
         [0063]    Although the present embodiments have been described to a certain degree of particularity, it should be understood that various alterations and modifications could be made without departing from the scope of the invention as hereinafter claimed.