Method for increasing the yield of potato crops

Abstract

The present document is directed to a method for increasing potato harvests by pre-treating the potato tubers with oxytocin for a short time period before the potato tubers are planted The present method may increase the yield of potato crop as regards number of potato tubers produced and / or weight of the produced potato tubers. The present document also discloses a method for increasing the yield of starch from plants, such as from potato tubers by pre-treating a plant, a part of a plant or a seed with an oxytocin solution.

Description

[0001] METHOD FOR INCREASING THE YIELD OF POTATO CROPS

[0002] TECHNICAL FIELD

[0003] The present document is directed to the field of cultivation of potatoes. Specifically, the present document is directed to a method for increasing the yield and / or quality of potato crops by pre-treating the potato tubers before planting.

[0004] BACKGROUND

[0005] Potatoes are an essential crop and a staple food in many countries. Due to its high content of carbohydrates, potatoes are a good source for energy. Also, potatoes are a good source for vitamins, such as vitamin B6, other B vitamins, and vitamin C.

[0006] Crop yield of potato varies largely between different countries and may depend on crop breed, seed age, crop management and environmental factors, such as soil composition, temperature and access to water.

[0007] Increasing the yield of potato harvests may have large impacts on the world-wide food supply and may in particular benefit farmers and populations in developing countries with limited food resources.

[0008] Oxytocin is a human nonapeptide hormone initially linked to e.g. milk ejection and uterine contractions. It was later found to also exert a wide spectrum of effects within the central nervous system as well as cardiovascular functions, to only mention a few effects linked to oxytocin. Oxytocin has also been found to stimulate the germination of plants when seed are germinated in a solution containing oxytocin (W002 / 102160). Further, WO2021 / 256979 discloses the use of oxytocin to stimulate the formation of calluses and roots on cuttings of plants by exposing the cuttings to oxytocin for prolonged time periods

[0009] As explained in the above, there is a need for further methods for improving the yield and quality of potato crops.SUMMARY

[0010] An object of the present invention is to provide means and methods for increasing the yield and quality of potato crops.

[0011] The present document is directed to a method for increasing the yield, i.e. the weight and / or number of potato tubers produced per potato tuber planted, and / or increasing the content of starch in potato tubers, said method comprising pre-treating a potato tuber with an oxytocin solution before planting said potato tuber. The pre-treatment with oxytocin is performed for a short time period for about 30 minutes or less, such as for 5 minutes or less. The oxytocin pre-treatment results in an oxytocin pre-treated potato tuber.

[0012] The oxytocin pre-treatment leads to an increased weight of the grown potato tubers produced per potato tuber planted and / or an increased number of potato tubers produced per potato tuber planted. Further, the content of starch in the potato tubers (i.e. a higher weight percentage of starch may be obtained) and / or the total yield of starch in a crop may be increased due to a higher total crop yield.

[0013] Thus, the present document is directed to a method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers, said method comprising pre-treating a potato with an oxytocin solution before planting said potato, wherein said pre-treatment with an oxytocin solution is performed for about 30 minutes or less, such for about 10 minutes or less, to provide an oxytocin pre-treated potato tuber. The increase in yield may be an increase in the weight and / or number of potato tubers produced per planted potato tuber.

[0014] The method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers may further comprise planting said oxytocin pre-treated potato tuber in a planting medium, such as a plant nutrient medium or soil.

[0015] The concentration of oxytocin in an oxytocin solution may from about 0.5 pM to about 50 pM, such as from about 1 pM to about 50 pM, from about 1 pM to about 30 pM, from about 1pM to about 20 pM, from about 1 pM to about 10 pM, from about 1 pM to about 8 pM, from about 2 pM to about 8 pM, from about 1 pM to about 6 pM, from about 1 pM to about 5 pM, from about 2 pM to about 6 pM, from about 3 pM to about 5 pM or from about 2 pM to about 4 pM.An oxytocin pre-treatment may be performed by spraying the potato tuber with the oxytocin solution or by placing the potato tuber in the oxytocin solution.

[0016] The method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers may further comprise drying the oxytocin pre-treated potato tuber for at least about one day, preferably in the dark, preferably at a temperature from about 2 °C to about 15 °C.

[0017] An oxytocin pre-treated potato tuber may be stored for from about 1 day to about 6 months before planting the potato tuber.

[0018] An oxytocin pre-treated potato tuber may be exposed to light before and / or after the pretreatment in oxytocin solution, such as for from about 1 day to about 35 days, such as from about 7 days to about 28 days, such as for from about 10 to about 25 days, such as for about 14 to about 21 days, preferably at a temperature from about 5 °C to about 20 °C, more preferably from about 10 °C to about 15 °C.

[0019] A pre-treatment with an oxytocin solution may be performed by spraying the oxytocin solution onto the potato tuber for from about 1 second to about 30 seconds, such as from about 5 to about 10 seconds.

[0020] An oxytocin pre-treated potato tuber may be planted immediately after the pre-treating with an oxytocin solution.

[0021] An oxytocin solution may comprise oxytocin according to SEQ ID NO: 1.

[0022] An oxytocin solution may comprise a variant of oxytocin possessing oxytocin activity, wherein the variant has an amino acid sequence according to SEQ ID NO: 2.

[0023] An oxytocin solution may comprise a fragment of oxytocin or a fragment of a variant of oxytocin according to SEQ ID NO: 1 or SEQ ID NO: 2, wherein the fragment possessing oxytocin activity.The present document is also directed to a potato tuber obtained or obtainable by the method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers.

[0024] The present document is also directed to a method for increasing the content of starch in a plant, wherein the method comprises exposing a plant, a part of a plant or a seed for a plant to an oxytocin solution. The plant may be a plant naturally rich in starch. The plant may be selected from the group consisting of potato, sweet potato, carrots, and turnip. The plant or seed for a plant may be treated with an oxytocin solution for from about 1 second to about 72 hours, such as 1 minute to about 72 hours, such as from about 5 minutes to about 72 hours, such as from about 15 minutes to about 72 hours, such as from about 0.5 hours to about 72 hours, such as from about 1 hour to about 48 hours, from about 1 hour to about 24 hours, from about 12 hours to about 48 hours, or from about 12 hours to about 24 hours. The concentration of oxytocin in the oxytocin solution may from about 0.5 μM to about 50 μM, such as from about 1 μM to about 50 μM, from about 1 μM to about 30 μM, from about 1 μM to about 20 μM, from about 1 μM to about 10 μM, from about 1 μM to about 8 μM, from about 2 μM to about 8 μM, from about 1 μM to about 6 μM, from about 1 μM to about 5 μM, from about 2 μM to about 6 μM, from about 3 μM to about 5 μM or from about 2 μM to about 4 μM. The oxytocin solution may comprise oxytocin according to SEQ ID NO: 1, a variant of oxytocin possessing oxytocin activity, wherein said variant has an amino acid sequence according to SEQ ID NO: 2 and / or a fragment of oxytocin or a fragment of a variant of oxytocin according to SEQ ID NO: 2, said fragment possessing oxytocin activity.

[0025] The present document is also directed to a plant, a part of a plant or a seed for a plant obtained or obtainable by the method for increasing the content of starch in a plant.

[0026] Other details regarding how to perform the method for increasing the content of starch in a plant may be as described for the method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers.

[0027] Other features and advantages of the invention will be apparent from the following detailed description, drawings, examples, and from the claims.DEFINITIONS

[0028] The singular forms “a”, “an” and “the” include plural references unless the context clearly dictates otherwise.

[0029] By “potato tuber” and the like is herein intended the enlarged portion of a potato plant growing underground.

[0030] By “oxytocin” is herein intended the human nonapeptide sequence, according to SEQ ID NO: 1, see e.g. W002 / 102160:

[0031] (SEQ ID NO: 1)

[0032] Cys-Tyr-lle-Gln-Asn-Cys-Pro-Leu-Gly-NH2

[0033] Variants of oxytocin having a similar effect on potato tubers as oxytocin as disclosed herein may be used as an alternative to oxytocin as such. Thus, whenever it is referred to “oxytocin” herein, this also includes variants of oxytocin. Accordingly, a “variant” of oxytocin as referred to herein, refers to a peptide which has been varied in its amino acid structure as compared to the oxytocin molecule in that some amino acid positions may have been altered by introducing other amino acids in such positions, such as natural or unnatural amino acids as exemplified herein, it may have been extended by adding one or more natural or unnatural amino acid(s) to either ends of the peptide. In addition, other structural variations may also have been performed to the present peptides as referred to herein, such as synthetic modifications. Said “variant” still maintains a biological activity similar to oxytocin. Thus, as used herein, a variant of oxytocin may have a sequence according to SEQ ID NO:2 possessing oxytocin activity:

[0034] (SEQ ID NO: 2) Xi-X2-X3-X4-Asn-Cys-X5-X6-X7-X8-NH2

[0035] wherein

[0036] X1 is selected from the group consisting of Cys and nothing;

[0037] X2is selected from the group consisting of Tyr, Phe, and nothing;

[0038] X3 is selected from the group consisting of Ile, Val, Hoph, Phe, Cha, and nothing;

[0039] X4 is selected from the group consisting of Gln, Ser, Thr, Cit, Arg, and Daba;

[0040] X5 is selected from the group consisting of Pro and nothing;

[0041] X6is selected from the group consisting of Ile, Leu, nothing, Val, Hos, Daba, Thr, Arg, and Cit;

[0042] X7 is selected from the group consisting of Gly, nothing, and Ala;Xs is selected from the group consisting of Gly and nothing. In SEQ ID NO: 2 there may be a cysteine bridge between Cys in position 1 and Cys in position 6 (counted from the N-terminal).

[0043] Furthermore, a “fragment” of oxytocin, as referred to herein is a peptide which comprises a part of the amino acid sequence of oxytocin according to SEQ ID NO: 1, but wherein one or more amino acids have been removed from one or both of the amino acid terminal end(s). This term also refers to a fragment of an oxytocin variant as defined in SEQ ID NO:2, hence meaning that also encompassed by the present invention is any fragment of a peptide as presented by SEQ ID NO: 2. Such fragments maintain a biological activity similar to oxytocin, thus such variants possess oxytocin activity.

[0044] The term “oxytocin solution” as used herein refers to a solution comprising oxytocin, a variant oxytocin and / or a fragment of oxytocin or a fragment of a variant of oxytocin. Typically, the oxytocin solution is aqueous. For example, the oxytocin solution may comprise or consist of oxytocin according to SEQ ID NO: 1, an oxytocin variant according to SEQ ID NO: 2, and / or a fragment of oxytocin according to SEQ ID NO: 1 or a fragment of a variant of oxytocin according to SEQ ID NO: 2.

[0045] The term “increasing the content of starch in potato tubers” and the like as used herein refers to an increase in the yield of starch obtained from potato tubers. Such an increase in yield of starch may be obtained by an increase in starch content in the individual potato tubers (i.e. an increased starch percentage in the potato tubers) and / or an increase in the crop yield, thus resulting in an increased total amount of starch obtained in a crop.

[0046] BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 shows the effects of pre-treatment of potato tubers with oxytocin solution (2 μm or 4 μm) on the weight of the crop (Fig. 1 a) and the number of potato tubers (buds) (Fig.

[0048] 1 b).

[0049] Figure 2 shows the effects of pre-treatment of potato tubers with oxytocin solution (2 μm or 4 μm) on the weight of the crop (dark grey bar) and starch content (light grey bar).DETAILED DESCRIPTION

[0050] The present document is directed to a method for increasing potato harvests (crops) and / or the yield of starch in potato. More specifically, the present document is directed to a method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers and / or potato crops. The method comprises pre-treating potato tubers with an oxytocin solution before planting the potato tubers wherein the pre-treatment with an oxytocin solution is performed for about 30 minutes or less, such for about 10 minutes or less. The present document is therefore also related to a method for pre-treating potato tubers before planting, said method comprising pre-treating potato tubers with an oxytocin solution before planting the potato tubers, wherein the pre-treatment with an oxytocin solution is performed for about 30 minutes or less, such for about 10 minutes or less. Details for such a method for pre-treating potato tubers before planting are as explained in the present document for the method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers. The oxytocin pre-treatment provides an oxytocin pre-treated potato tuber.

[0051] As is demonstrated in the experimental section, it was found that an unexpectedly short treatment time with the oxytocin solution still provided positive effects on the potato crop yield and / or starch content of the potato tubers. By an increased yield as used herein it is intended that the total weight of the crop and / or number of potato tubers produced from a planted potato tuber is increased relative to when potato tubers have not been pre-treated with the method of the present document. Thus, an increased yield typically means a higher total weight of the crop. Such a higher total weight of the crop may be effected by an increase in the number of potato tubers obtained and / or an increase in the weight of the individual potato tubers. An increased yield of starch using the oxytocin pre-treatment may be obtained by an increased content of starch in the potato tubers (i.e. a higher starch percentage in the potato tubers) and / or a higher total amount of starch in a crop due to a higher crop yield. The total weight of potato tubers and / or total yield of starch obtained from a planted potato tuber may thus be increased by the method of the present document. It has previously been disclosed in WO2021 / 256979 that the number of sprouts of a potato tuber can be increased by treating the potato tuber with an oxytocin solution for 6 or 24 hours. According to WO2021 / 256979, the potato tubers are soaked in an oxytocin solution for six hours or more. In view of this, it is highly surprising that an increased potato crop yield can be obtained by pre-treating potato tubers with an oxytocin solution before planting for the very short times disclosed in the present document, asthese short treatment times will only allow very small amounts of oxytocin to be delivered to the potato tubers. Further, it is highly surprising that pre-treating potato tubers with oxytocin may increase the yield of starch.

[0052] According to the present method, the potato tubers are exposed to oxytocin for only about 30 minutes or less, such for about 15 minutes or less, such as for about 10 minutes or less, such as for about 5 minutes or less, such as for from about 1 second to about 30 minutes, such as for from about 1 second to about 15 minutes, such as for from about 1 second to about 10 minutes, such as for from about 1 second to about 8 minutes, such as for from about 1 second to about 5 minutes, such as for from about 1 second to about 3 minutes, such as for from about 1 second to about 1 minute, such as from about 1 second to about 30 seconds, such as from about 1 second to about 15 seconds, such as from about 1 second to about 10 seconds, or such as from about 1 second to about 5 seconds. The minimum treatment time may be from 1 second, such as 5 seconds, 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds or one minute. Such short treatment times are beneficial as they allow an easy handling of the large amounts of potato tubers that usually need to be handled when growing potato, in particular for commercial potato farming.

[0053] After the pre-treatment with oxytocin, the oxytocin pre-treated potato tubers may be directly planted or may be stored for a shorter or longer period of time, in light or darkness, before planting as described in more detailed herein.

[0054] The oxytocin pre-treated potato tubers are planted according to standard methodology. Typically, the oxytocin pre-treated potato tubers are planted in soil or in a plant nutrient medium. The planting may be performed manually or using regular potato planting equipment.

[0055] The concentration of oxytocin and / or a variant or fragment thereof (i.e. the total concentration of oxytocin, variant(s) and / or fragment(s) in the oxytocin solution is typically from about 0.5 μM to about 50 μM, such as from about 1 μM to about 50 μM, from about 1 μM to about 30 μM, from about 1 μM to about 20 μM, from about 1 μM to about 10 μM, from about 1 μM to about 8 μM, from about 2 μM to about 8 μM, from about 1 μM to about 6 μM, from about 1 μM to about 5 μM, from about 2 μM to about 6 μM, from about 3 μM to about 5 μM or from about 2 μM to about 4 μM. The oxytocin solution may have a pH offrom about 1 to about 9, such as from about 2 to about 8, from about 2 to about 7, from about 2 to about 6, from about 2 to about 5, from about 2 to about 4, from about 3 to about 5, from about 3 to about 4, such as about 1, 2, 3, 4, 5, 6, 7, 8, or 9. The oxytocin solution is typically aqueous. The oxytocin solution may further comprise a liquid(s) and / or solid carrier(s), excipient(s), organic fertilizer(s), pH adjusting agent(s) and / or agricultural agent(s). Preferably, the oxytocin solution consists of oxytocin and water. The oxytocin may be present in both D- and L-form, as well as racemates thereof. By inversion of the peptide sequence thereof, the D-form could be converted to the L-form. The peptides above can be produced by methods known to a person skilled in the art, e.g. according to Merrifield, P. B., " Solid Phase Synthesis", Angew. Chemie, 1985, No. 97, p. 801.

[0056] The oxytocin solution may be applied to the potato tuber in any suitable manner allowing the short treatment times according to the present document. Typically, the oxytocin solution is applied to the potato tuber by covering the potato tuber with the oxytocin solution, such as by placing or dipping the potato tuber in the oxytocin solution or by spraying the oxytocin solution onto the potato tuber. The potatoes may be moved after application of oxytocin to enable that a larger part of the potato surface gets covered with oxytocin solution. When the pre-treatment with an oxytocin solution is performed by spraying, the oxytocin solution may be sprayed on the potato tuber for a very short time period, such as for from about 1 second to about 30 seconds, such as from about 5 to about 10 seconds. As the treatment times with the oxytocin solution are so short, the temperature during the oxytocin pre-treatment is not critical as long as it does not harm the potato tubers or the oxytocin solution. Typically, the temperature during the oxytocin pre-treatment is 40 °C or lower, such as 25 °C or lower, and 1°C or higher, such as 2 °C or higher or 4 °C or higher.

[0057] Typically, the whole potato tuber is provided with oxytocin solution, but it may be sufficient to provide the oxytocin solution to only part of the potato tuber, for example such that at least about 50%, such as about at least 75% of the surface of the potato tuber is provided with oxytocin solution. As is demonstrated in the experimental section, the oxytocin solution may conveniently be applied to the potato tuber in connection with planting the potato tuber by spraying the oxytocin solution onto the potato tuber using regular potato tuber planting equipment adapted to apply a composition (such as a fertilizer, pesticide etc.) to the potato tubers upon planting. The potato tuber may therefore be planted within about 30 minutes from the pre-treatment with oxytocin solution, such as within about 20minutes, within about 10 minutes, within about 5 minutes, within about 1 minute, within about 30 seconds, within about 15 seconds, within about 10 seconds, or within about 5 seconds after applying the oxytocin solution to the potato tuber.

[0058] The potato tuber may be dried before further storage or planting. For example, the oxytocin pre-treated potato tuber may be allowed to dry for at least about one day, preferably in the dark. Typically, the temperature during such drying is from about 2 °C to about 15 °C, such as from about 2 °C to about 10 °C, such as from about 2 °C to about 5 °C, such as about 4°C.

[0059] Instead of planting the potato tuber within a short time period after the oxytocin solution has been applied, it is possible to store the potato tuber before planting. Such storing may be in the dark. Storing the oxytocin pre-treated potato tuber in the dark is beneficial to prevent sprouting of the potato tuber. If the oxytocin pre-treated potato tuber is to be stored before planting, this is typically done at lower temperatures such as from about 2 °C to about 15 °C, such as from about 2 °C to about 10 °C, such as from about 2 °C to about 5 °C, such as about 4°C. Typically, the potato tuber is not stored for more than 6 months before planting and more typically for not more than 3 months, such as for from about 1 day to about 3 months, such as from about 1 day to about 2 months, such as from about 1 day to about 1 months, such as from about 1 day to about 1 week, or such as from about 1 week to about 1 month.

[0060] The potato tuber may be exposed to light before planting. Such a treatment is commonly used in order to prepare the potato tuber for growth and may cause sprouting of the potato tuber. In accordance with the method of the present document, the potato tuber may be exposed to light before and / or after the pre-treatment with oxytocin solution, preferably after the pre-treatment with oxytocin solution. For example, the potato tuber may be exposed to light for from about 1 day to about 35 days, such as for from about 7 days to about 28 days, such as for from about 10 to about 25 days, such as for from about 14 to about 21 days, preferably at a temperature from about 5 °C to about 20 °C, more preferably from about 10 °C to about 15 °C.

[0061] The potato tuber may be treated (before or after planting) with e.g. fertilizers and / or pesticides as regularly used when growing potatoes. However, due to the effects of the oxytocin on potato, the need for such treatments may be decreased. Preferably, oxytocinis only applied to the potato tubers before planting, i.e. no further oxytocin is added once the potato tubers are planted.

[0062] The amount of oxytocin solution used may be from about 10 ml to about 1 litre per kg potato, such as from about 50 ml to about 1 litre per kg, such as from about 100 ml to about 1 litre per kg, such as from about 100 ml to about 500 ml per kg, such as from about 100 ml to about 300 ml, such as from about 200 ml to about 300 ml. These amounts are particularly suitable when applying the oxytocin solution by spraying onto the potato tubers.

[0063] One advantage with the present method is that the oxytocin is applied to the potato tuber before planting, i.e. only the potato tuber and not the soil or plant nutrient medium in which the potato grows is treated with the oxytocin. The potato tuber is therefore removed from the oxytocin solution before being planted. Treating only the potato tuber and not the soil or plant nutrient medium with the oxytocin solution reduced the amount of oxytocin necessary to use. Further, as soil is not treated with oxytocin, the present method allows a reduced spreading of oxytocin to the environment. The present method is therefore useful in precision farming (precision agriculture) strategies. Preferably, the potato tubers are only pre-treated with oxytocin, i.e. no oxytocin treatment is performed once the potato tubers are planted.

[0064] As is demonstrated in the experimental section, despite the short pre-treatment times used, the present method allows for an increased yield of potato crops (see Examples 1-3). The increase in yield may be an increase in the number of potato tubers and / or the weight of the potato tubers produced per potato tuber planted relative to when potato tubers are not pre-treated with oxytocin according to the method disclosed herein. The present method may thus allow for obtaining a higher total weight of potato tubers produced per potato tuber planted. Thus, the present method may allow for increasing the potato crop per cultivation surface area. This increase of potato crop may be obtained without increasing the number of potato tubers planted or the same yield of potato tubers may be obtained while planting fewer potato tubers. Further, the starch content in the potato tubers and / or total amount of starch in the crop may be increased as is demonstrated in Examples 2, 4, and 5. Thus, potato tubers with a higher wt% of starch and / or a higher total amount of starch in the crop (due to a higher crop yield) may be obtained by the present method.When using an oxytocin pre-treatments according to the present document, a regular fertilization schedule may be used, such as with NPK fertilizers. However, it may additionally or alternatively be preferable to treat the potato plants with NPK fertilizer by spraying the potato plants at a time point between the development of the shaw and when the flower buds develop, at a time point between the development of the flower buds and when the potato starts flowering, and / or during the development of the tubers. The methods of the present document may therefore also comprise a step of fertilization with a NPK fertilizer according to such a treatment schedule.

[0065] The potato tuber treated with oxytocin according to the present document may be any potato tuber intended to be planted. Generally, the potato tuber to be treated with oxytocin solution is a so called "seed potato". Seed potatoes are potato tubers specifically grown to be free from diseases etc. in order to be suitable for planting. Such seed potatoes may also be grown only a limited number of times from the same stock to ensure vigour. Being able to treat seed potato according to the present document to increase the crop yield and / or quality of the potato tubers is of large commercial value.

[0066] The present document is also directed to a potato tuber obtained or obtainable by the method disclosed herein.

[0067] The present document is also directed to method for increasing the content of starch in plants said method comprising exposing a plant or seed for a plant to oxytocin. The present document is thus also directed to a method for increasing the content of starch in a plant, said method comprising exposing a plant, a part of a plant or a seed for a plant to an oxytocin solution as defined herein. Examples of plants or seeds for plants that can be treated with such a method include starch-rich plants such as potato, sweet potato, carrots, turnip etc. in particular in plants having tubers, such as potato and sweet potato. Oxytocin in such a method may be provided in a solution as described elsewhere herein. The oxytocin may be applied to the plant or seed of a plant using a method as described herein. The treatment times may be as described herein for the method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers or a treatment time of from about 1 second to about 72 hours, such as from about 1 minute to about 72 hours, such as from about 5 minutes to about 72 hours, such as from about 15 minutes to about 72 hours, such as from about 0.5 hours to about 72 hours, such as fromabout 1 hour to about 48 hours, from about 1 hour to about 24 hours, from about 12 hours to about 48 hours or from about 12 hours to about 24 hours may be used. The oxytocin may be applied directly to the plant, or seed for a plant and / or it may be provided to the growth medium, such as by watering the plant medium with an oxytocin containing solution. The concentration of oxytocin in the oxytocin solution in such a method is as disclosed elsewhere herein, i.e. typically from about 0.5 μM to about 50 μM, such as from about 1 μM to about 50 μM, from about 1 μM to about 30 μM, from about 1 μM to about 20 μM, from about 1 μM to about 10 μM, from about 1 μM to about 8 μM, from about 2 μM to about 8 μM, from about 1 μM to about 6 μM, from about 1 μM to about 5 μM, from about 2 μM to about 6 μM, from about 3 μM to about 5 μM or from about 2 μM to about 4 μM. The oxytocin solution may be applied to the plant, the part of a plant or the seed by spraying or by placing the plant, the part of a plant in oxytocin solution. As disclosed elsewhere herein, the oxytocin solution may comprise oxytocin according to SEQ ID NO: 1 and / or the oxytocin may be a variant of oxytocin possessing oxytocin activity, according to SEQ ID NO: 2, and / or the oxytocin may be a fragment of oxytocin according to SEQ ID NO: 1 or SEQ ID NO: 2, said fragment possessing oxytocin activity. Other details regarding how to perform a method for increasing the content of starch in a plant are as described elsewhere herein. The present document is also directed to a plant, a part of a plant or a seed for a plant obtained or obtainable by the method for increasing the content of starch in a plant.

[0068] The invention will be further described in the following examples, which do not limit the scope of the invention described in the claims.

[0069] EXPERIMENTAL SECTION

[0070] Preparation of oxytocin solution: Oxytocin was dissolved in tap water and mixed thoroughly. Two test concentrations were used, 2 μM and 4 μM of oxytocin. As a control, tap water was used.

[0071] EXAMPLE 1: Pre-treatment with oxytocin by placing potato tubers in an oxytocin solution

[0072] Seed potatoes (variety Gala) were placed in a glass or stainless-steel bucket with open bottom and oxytocin solution (2 μM or 4 μM oxytocin in water) added to cover the potatotubers. Control potato tubers were placed in tap water. After 5-10 min in the oxytocin solution or tap water, the potato tubers were removed therefrom.

[0073] The potato tubers were then allowed to dry for one to two days (in the darkness at about 4 °C) and thereafter activated by light for one day. The potato tubers were thereafter placed on a conveyer table in light for about three weeks and allowed to sprout.

[0074] The potato tubers were then planted in soil and fertilizer was added at the time of planting using standard practices (500 kg / ha NPK 11-5-18 Pro Magna). During the growth period, weed was regularly removed.

[0075] After ca 2.5 months, potato tubers were harvested, and the number of potato tubers and weight of the crops was compared between the different treatments.

[0076] As can be seen in Fig. 1, both the weight of the crop (i.e. the total weight of potato tubers obtained) (Fig. 1 a) and the number of potato tubers (buds) (Fig. 1 b) formed increased when the potato was pre-treated with a 2 μm or 4 μm oxytocin solution before planting.

[0077] EXAMPLE 2: Pre-treatment with oxytocin by spraying potato tubers with an oxytocin solution

[0078] Seed potatoes (of the variety Saprodi) were activated for about 2 weeks by placing the potatoes in light at 10 °C.

[0079] Oxytocin was sprayed onto the potato tubers using a nozzle mounted on the planting equipment.

[0080] 25 litres of oxytocin solution (2 μM or 4 μM oxytocin in water) or tap water (for control) was used per 900 kg seed potatoes.

[0081] The potato tubers were then immediately planted, so that the time from application of oxytocin until the potato tubers were in the soil and covered with it was about 5-10 seconds. Fertilizer was added at the time of planting using standard practices (500 kg / ha NPK 11-5-18 Pro Magna).The potato plants were treated with pesticides against leaf mould three times during the growth period. Potato tubers from the three different treatments were harvested on the same day. The starch content of the potato tubers was analysed three weeks after harvest.

[0082] Table 1. Crop yield and starch content of oxytocin pre-treated potatoes and control Treatment Crop yield kg / ha Wt% starch

[0083] Tap water 56672 20.5

[0084] 2 μm oxytocin 58518 22.6

[0085] 4 μm oxytocin 59072 21.5

[0086]

[0087] As can be seen in Table 1 and Fig. 2, the potatoes obtained from seed potato pre-treated with oxytocin solution had a higher content of starch and a larger crop yield was obtained than for the control. The slightly lower starch content obtained in the potato tubers of the seed potatoes treated with 4 μm oxytocin compared to the seed potatoes treated with 2 μm oxytocin may, without wishing to be bound by theory, be due to the higher weight (yield) of the potato tubers resulting from the seed potatoes treated with 4 μm oxytocin, which may have decreased the wt% starch.

[0088] EXAMPLE 3: Pre-treatment with oxytocin of different varieties of potato

[0089] Potato of the variants Sunshine, Inova, Annabelle, Lady Claire, Santera, Lady Alicia, Trippie 7, and Saprodi were pre-treated with oxytocin before planting.

[0090] The potato tubers were pre-treated with an oxytocin solution (3 μM oxytocin in water). The oxytocin was applied to the potato tubers upon planting, e.g. via a planter. As a control, potato tubers treated with water was used.

[0091] The results of the oxytocin pre-treatment are presented in Table 2 in the below.

[0092] Table 2. Comparison of increase in yield (i.e. total weight of the crops) between different varieties of potato after pre-treatment with oxytocin compared to control.Potato variety Increase in yield using oxytocin pretreatment

[0093] Sunshine 18%

[0094] Inova 14%

[0095] Annabelle 22%

[0096] Lady Claire 20%

[0097] Santera 17.7%

[0098] Lady Alicia 25%

[0099] Trippie 7 15%

[0100] Saprodi 15%

[0101]

[0102] As can be seen in Table 2, the oxytocin pre-treatment substantially increased the yield of the crops of potato for a number of different potato varieties. The positive effect of oxytocin pre-treatment according to the present document is therefore demonstrated to be independent of the potato variety.

[0103] EXAMPLE 4: Effect of oxytocin pre-treatment on starch production

[0104] Potato tubers of the variant Stratos (a potato variant used for starch production) were pretreated with an oxytocin solution (3 μM oxytocin in water) upon planting. The oxytocin solution was applied by using a planter with a round nozzle. The use of a planter for the application of the oxytocin solution means that the treatment time with oxytocin solution was very short. The working pressure was minimum 3 bar. At least 90 litres of oxytocin solution was used per hectare planted with potato. The coverage of oxytocin solution on the potato tubers was good. The potato tubers were also treated with a commercial fungicide, applied to the potato tubers according to the manufacturer’s instructions. As a control, untreated potato and potato treated with two different amounts of the commercial fungicide were used.

[0105] Table 3. Comparison of yield in starch with different treatments of potato tubers Treatment % starch HKg tubers / ha HKg starch Yield increase in DKK / ha* Untreated 22.4 624 139.5 -

[0106]

[0107] 0.75 22.6 622 140.1 300 fungicide / ha

[0108] 0.375 22.6 606 136.1 -1700 fungicide / ha

[0109] 0.75 22.6 648 146.5 3500 fungicide / ha +

[0110] oxytocin

[0111]

[0112] *Based on a starch price of 5.00 DKK / kg

[0113] It was observed that by using a combination of a commercial fungicide and oxytocin pretreatment, a very high yield of potato crops and starch per hectare planted could be obtained. Interestingly, the oxytocin pre-treatment allowed the amount of fungicide to be drastically reduced while still enabling a higher crop and starch yield than if the potato tubers were treated with a higher amount of fungicide.

[0114] EXAMPLE 5: Effect of oxytocin pre-treatment on starch production

[0115] Potato tubers of the variant Nofy were pre-treated with an oxytocin solution (3 μM oxytocin in water) upon planting. The oxytocin solution was applied by using a planter, meaning that the oxytocin solution was applied during a very short time period. The potatoes were treated with a combination of oxytocin, a commercial fungicide and a commercial agent improving the coverage of the fungicide on the treated potatoes (+ oxytocin in Table 4) or only the fungicide and the agent improving coverage (- oxytocin in Table 4). The fungicide and the agent improving coverage were applied to the potato tubers according to the manufacturer’s instructions. The results are shown in Table 4 below.

[0116] Table 4. Comparison of yield in starch with different treatments of potato tubers Treatment Harvest row 1 Harvest row 2 Starch % HKg starch / ha HKg / ha HKg / ha

[0117] - oxytocin 382 358 20.9 67

[0118] + oxytocin 420 401 21.1 74.8

[0119]

[0120] As can be seen in Table 4, oxytocin pre-treatment resulted in an increased yield of starch as a result of both an increase in the percentage of starch in the potato tubers and an increase in crop yield.

[0121] It is to be understood that while the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims.

[0122] Unless expressly described to the contrary, each of the preferred features described herein can be used in combination with any and all of the other herein described preferred features.

Claims

CLAIMS1. A method for increasing the yield of potato tubers and / or increasing the content of starch in potato tubers, said method comprising pre-treating a potato with an oxytocin solution before planting said potato, wherein said pre-treatment with an oxytocin solution is performed for about 30 minutes or less, such for about 10 minutes or less, to provide an oxytocin pre-treated potato tuber.

2. The method according to claim 1, wherein said yield is an increase in the weight and / or number of potato tubers produced per planted potato tuber.

3. The method according to claim 1 or 2, said method further comprising planting said oxytocin pre-treated potato tuber in a planting medium, such as a plant nutrient medium or soil.

4. The method according to any one of the preceding claims, wherein the concentration of oxytocin in said oxytocin solution is from about 0.5 μM to about 50 μM, such as from about 1 μM to about 50 μM, from about 1 μM to about 30 μM, from about 1 μM to about 20 μM, from about 1 μM to about 10 μM, from about 1 μM to about 8 μM, from about 2 μM to about 8 μM, from about 1 μM to about 6 μM, from about 1 μM to about 5 μM, from about 2 μM to about 6 μM, from about 3 μM to about 5 μM or from about 2 μM to about 4 μM.

5. The method according to any one of the preceding claims, wherein said pretreatment is performed by spraying the potato tuber with said oxytocin solution or by placing said potato tuber in said oxytocin solution.

6. The method according to any one of the preceding claims, said method further comprising drying the oxytocin pre-treated potato tuber for at least about one day, preferably in the dark, preferably at a temperature from about 2 °C to about 15 °C.

7. The method according to any one of the preceding claims, wherein said oxytocin pre-treated potato tuber is stored for from about 1 day to about 6 months before planting said potato tuber.

8. The method according to any one of the preceding claims, wherein said oxytocin pre-treated potato tuber is exposed to light before and / or after said pre-treatment in oxytocin solution, such as for from about 1 day to about 35 days, such as from about 7 days to about 28 days, such as for from about 10 to about 25 days, such as for about 14 to about 21 days, preferably at a temperature from about 5 °C to about 20 °C, more preferably from about 10 °C to about 15 °C.

9. The method according to any one of the preceding claims, wherein said pretreatment with an oxytocin solution is performed by spraying said oxytocin solutiononto said potato tuber for from about 1 second to about 30 seconds, such as from about 5 to about 10 seconds.

10. The method according to any one of claims 1-5 and 8-9, wherein the oxytocin pretreated potato tuber is planted immediately after said pre-treating with an oxytocin solution.

11. The method according to any one of the preceding claims, wherein said oxytocin solution comprises oxytocin according to SEQ ID NO: 1.

12. The method according to any one of the preceding claims, wherein said oxytocin solution comprises a variant of oxytocin possessing oxytocin activity, wherein said variant has an amino acid sequence according to SEQ ID NO: 2.

13. The method according to any one of the preceding claims, wherein said oxytocin solution comprises a fragment of oxytocin according to SEQ ID NO: 1 or a fragment of a variant of oxytocin according to SEQ ID NO: 2, said fragment possessing oxytocin activity.

14. A potato tuber obtained or obtainable by the method according to any one of claims 1-13.

15. A method for increasing the starch yield from plants, said method comprising exposing a plant, a part of a plant or a seed for a plant to an oxytocin solution.

16. The method according to claim 15, wherein said plant is selected from the group consisting of potato, sweet potato, carrots, and turnip.

17. The method according claim 15 or 16, wherein said plant, part of a plant or seed for a plant is treated with an oxytocin solution for from about 1 second to about 72 hours, such as 1 minute to about 72 hours, such as from about 5 minutes to about 72 hours, such as from about 15 minutes to about 72 hours, such as from about 0.5 hours to about 72 hours, such as from about 1 hour to about 48 hours, from about 1 hour to about 24 hours, from about 12 hours to about 48 hours, or from about 12 hours to about 24 hours.

18. The method according to any one of claims 15-17, wherein the concentration of oxytocin in said oxytocin solution is from about 0.5 μM to about 50 μM, such as from about 1 μM to about 50 μM, from about 1 μM to about 30 μM, from about 1 μM to about 20 μM, from about 1 μM to about 10 μM, from about 1 μM to about 8 μM, from about 2 μM to about 8 μM, from about 1 μM to about 6 μM, from about 1 μM to about 5 μM, from about 2 μM to about 6 μM, from about 3 μM to about 5 μM or from about 2 μM to about 4 μM.

19. The method according to any one of claims 15-18, wherein said oxytocin solution comprises oxytocin according to SEQ ID NO: 1.

20. The method according to any one of claims 15-19, wherein said oxytocin solution comprises a variant of oxytocin possessing oxytocin activity, wherein said variant has an amino acid sequence according to SEQ ID NO: 2.

21. The method according to any one of claims 15-20, wherein said oxytocin solution comprises a fragment of oxytocin according to SEQ ID NO: 1 or a fragment of a variant of oxytocin according to SEQ ID NO: 2, said fragment possessing oxytocin activity.

22. A plant, a part of a plant or a seed for a plant obtained or obtainable by the method according to any one of claims 15-21.

Images