Control of control of metabolite production in Plants By Simultaneous Injection With CO2 and O2

Abstract

As part of the natural biological process, plants produce various metabolites. The amount of certain metabolites produced is important, especially during the growth phase of plants to be harvested in whole or in part. The production of metabolites is affected by the chemical environment within the plant, including the amount of CO.sub.2 and O.sub.2. The production of metabolites of interest can be controlled by measuring the amount of the metabolites being produced by the plant, and then adjusting the amount of CO.sub.2 and O.sub.2 available to the plant. These are adjusted by adjusting the amount of CO.sub.2 in water delivered to the leaves of the plant through foliar spraying and the amount of O.sub.2 in water delivered to the roots of the plant.

Claims

1. A method of controlling metabolite production in a crop of plants of a species, comprising: (a) delivering CO.sub.2-infused water to leaves of all plants within the crop by foliar spraying; (b) delivering O.sub.2-infused water to roots of all plants within the crop by root feeding the plants; (c) measuring an amount of a particular metabolite within a subset of at least one plant of the crop; (d) determining whether the amount of the particular metabolite is within a target range; (e) if the amount of the particular metabolite is not within the target range: adjusting the amount of CO.sub.2 being infused into the CO.sub.2-infused water; and adjusting the amount of O.sub.2 being infused into the O.sub.2-infused water; and (f) repeating steps (a)-(e) intermittently until the crop is harvested or until the plants in the crop reach the end of their life cycle.

2. The method of claim 1 wherein the subset of at least one plant comprises more than one plant, and wherein determining whether the mount of the particular metabolite is within the target range comprises determining whether a statistical measure of all measured amounts of the metabolite is within the target range.

3. The method of claim 1 wherein the particular metabolite is ethylene, and wherein step (e) comprises: (e)(i) if the amount of ethylene is below the target range: increasing the amount of CO.sub.2 being infused into the CO.sub.2-infused water; decreasing the amount of O.sub.2 being infused into the O.sub.2-infused water; and (e)(ii) if the amount of ethylene is above the target range: decreasing the amount of CO.sub.2 being infused into the CO.sub.2-infused water; increasing the amount of O.sub.2 being infused into the O.sub.2-infused water.

4. The method of claim 1 wherein the particular metabolite is vitamin C, and wherein step (e) comprises: (e)(i) if the amount of vitamin C is below the target range: increasing the amount of CO.sub.2 being infused into the CO.sub.2-infused water; decreasing the amount of O.sub.2 being infused into the O.sub.2-infused water.

5. The method claim 1 wherein measuring an amount of a particular metabolite within a subset of at least one plant of the crop comprises measuring the amount of metabolite present directly.

6. The method claim 1 wherein measuring an amount of a particular metabolite within a subset of at least one plant of the crop comprises measuring the amount of metabolite present indirectly.

7. The method of claim 6 wherein measuring the amount of the metabolite indirectly comprises measuring an amount of mRNA associated with production of the metabolite.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The method of the invention is applied to an entire crop of plants, as described below. However, for simplicity the invention will be described with reference to a single plant.

[0011] The amount of a particular metabolite in a plant is measured, either directly or indirectly. For some metabolites the amount of the metabolite may be measured directly by simple extraction of the fluid in a cell and measuring the amount of metabolite. Such direct measurement would be appropriate for vitamin C or oil, for example. Other metabolites, particularly some exotic proteins, do not lend themselves to direct measurement. Instead, an indirect measurement of the amount of the metabolite must be made. Measurement of the amount of mRNA carrying instructions for producing the metabolite is made, for example using real-time polymerase chain reaction to quantify the amount of the particular mRNA present. As mRNA activity is directly correlated with production of the corresponding protein, an indirect measurement of the amount of the metabolite is possible.

[0012] A target range for the metabolite is selected. It is determined whether the measured amount of the metabolite is outside the target range. If the measured amount of the metabolite is not within the target range, then the amount of CO.sub.2 and O.sub.2 made available to the plant is adjusted simultaneously. CO.sub.2 is made available to the plant through foliar spraying of the leaves of the plant with CO.sub.2-infused water. The amount of CO.sub.2 made available to the plant is adjusted by altering the amount of CO.sub.2 being infused into the water. If more CO.sub.2 is desired then the amount of CO.sub.2 being infused into the water is increased, and if less CO.sub.2 is desired then the amount of CO.sub.2 being infused into the water is decreased. O.sub.2 is made available to the plant through root feeding of the plant with O.sub.2-infused water. The amount of O.sub.2 made available to the plant is adjusted by altering the amount of O.sub.2 being infused into the water. If more O.sub.2 is desired then the amount of O.sub.2 being infused into the water is increased, and if less O.sub.2 is desired then the amount of O.sub.2 being infused into the water is decreased.

[0013] The amount of CO.sub.2 and O.sub.2 adjustment will depend on the particular metabolite and may depend on the particular species of the plant. For example, suppose the metabolite of interest was ethylene. If extra CO.sub.2 is delivered to the plant leaves to produce carbohydrates, respiration rates in the roots or shoot must increase to use this surplus carbohydrate. If respiration does not increase, ethylene is produced which slows the metabolism of the plant leaves. By controlling both CO.sub.2 and O.sub.2 supplies in the plant, ethylene production can be regulated. If the measured amount of ethylene is below a target range and more ethylene is desired, the amount of CO.sub.2 made available to the plant is increased and the amount of O.sub.2 made available to the plant is decreased so as to slow respiration. If the measured amount of ethylene is above the target range and less ethylene is desired, the amount of CO.sub.2 made available to the plant is decreased and the amount of O.sub.2 made available to the plant is increased so as to raise the respiratory rate and slow ethylene production. The changes in the amounts of CO.sub.2 and O.sub.2 are accomplished as set out above.

[0014] As another example, suppose the metabolite of interest was vitamin C in oranges. If the amount of vitamin C being produced is below a target range, then the amount of CO.sub.2 being delivered to the plant is increased and the amount of O.sub.2 being delivered to the plant is decreased. This triggers the production of excess vitamin C in oranges. The increase in CO.sub.2 and the decrease in the amount of O.sub.2 is accomplished as set out above. Since more than usual amounts of vitamin C is not usually a concern, the upper limit of the target range can be considered to be effectively infinite, or at least a very high number.

[0015] Measurement of production of the metabolite and possible adjustment of the CO.sub.2 and O.sub.2 levels is carried out throughout the life cycle of the plant or until harvest. The frequency of measurement of metabolite production depends on the plant species, but may be on the order of days or weeks.

[0016] As the invention involves the adjustment of CO.sub.2 and O.sub.2 levels, the metabolite of interest must be within the carbohydrate demand and respiration activity metabolic pathways. Non-limiting examples of such metabolites are ethylene, vitamin C, plant oil, THC, and CBD. However, within this constraint, the method of the invention is the same for all metabolites and all plant species. Specific parameters of the method are dependent on the particular metabolite and the plant species to which the invention is being applied. The plant species is a higher order photosynthetic plant species having leaves or other surfaces capable of receiving foliar sprays, particularly leafy green plants.

[0017] The invention has been described for simplicity with respect to a single plant. More practically, the method of the invention would be applied to a number of plants in a crop in order to produce statistically significant measures of the metabolite production. In such an embodiment, the metabolite levels of a subset of at least one plant within a crop of more than one plant of the same species would be measured intermittently, and for each set of measurements a statistical measure is taken. A very simple example would be to take the average of all measurements of metabolite production. Using the statistical measure, the CO.sub.2 infused into the water used for foliar spraying and the O.sub.2 infused into water used for feeding the roots is adjusted. Foliar spraying and root feeding of the entire crop with the CO.sub.2-infused water and the O.sub.2-infused water, respectively, would be carried out with the new amounts of CO.sub.2 and O.sub.2.

[0018] The embodiments presented are exemplary only and persons skilled in the art would appreciate that variations to the embodiments described above may be made without departing from the spirit of the invention. The scope of the invention is solely defined by the appended claims.