MX2012013434A

MX2012013434A - Bacterial injection in sugarcane.

Info

Publication number: MX2012013434A
Application number: MX2012013434A
Authority: MX
Inventors: Leandro Martinho; Murlio Moreira; Jose Claudionir
Original assignee: Syngenta Participations Ag
Priority date: 2010-05-21
Filing date: 2011-05-20
Publication date: 2013-01-22
Also published as: AU2011254549A1; WO2011144741A2; WO2011144741A3; CN103025169A; CO6640234A2

Abstract

Methods of treating sugarcane, methods of growing sugarcane, and sugarcane propagation systems are shown and described. In one example, a method of treating includes injecting a mixture including nitrogen-fixing bacteria into a stem section.

Description

BACTERIAL INJECTION IN SUGAR CANE Description of the invention The present invention relates to the treatment of the sugarcane propagation material and, in particular, to the injection of mixtures that include bacteria in stem sections of sugarcane.

Plants need biologically useful forms of nitrogen for several reasons, for example, to synthesize proteins, nucleic acids and chlorophyll. Illustrative biologically useful nitrogen forms include nitrate (N03") and ammonium (NH4 +). However, useful forms of nitrogen are often depleted rapidly in agricultural systems, in which farmers can invest a significant amount of resources to supplement the floor.

Biologically useful forms of nitrogen can come from a variety of sources, including dinitrogen (N2), which is relatively abundant in the atmosphere. Before the dinitrogen is useful for most plants, it must be fixed or converted into another easier to use form such as ammonia (NH3). It is known that nitrogen fixation occurs through symbiotic nitrogen fixation associations between plants and bacteria. The best known is the association between certain species of bacteria, p. ex. , of the genera Rhizobium and Bradyrhizobium (also called REF. : 237296"rhizobia" in the present) and leguminous plants.

In legume plants, the process of nitrogen fixation involves a series of interactions between host and rhizobia that can be summarized as follows: (1) colonization of rhizobia in the rhizosphere and union of rhizobia to epidermal cells and radical hair; (2) curling of the root hair and invasion of the rhizobia to form infection threads; (3) initiation and development of nodules in the cortex of the roots; and (4) release of rhizobia from infection threads and initiation of nitrogen fixation.

It has also been discovered that some non-legume plants may have an association with nitrogen-fixing bacteria. Sugarcane is an example of a non-legume plant that may have associations with nitrogen-fixing bacteria. The term "sugar cane", as used herein, includes, for example, members of the genus Sa.cch.arum, p. ex. , S. arundinaceum, S. bengalense, S. edule, S. munja, 3. officinarum, S. procerum, S. ravennae, S. robustum, S. sinense and S. spontaneum.

The sugarcane plant is important from a commercial point of view for several reasons that include the production of sugar, Falernum, molasses, rum, cachaça (the national liquor of Brazil) and ethanol for fuels. In addition, the remaining biomass after crushing the sugar cane can also be used in furnaces and boilers. Because of its commercial importance, hundreds of acres of sugarcane are grown every year.

Sugar cane can be grown in several ways. For example, sugar cane can be grown from seeds or stem sections (also known as cuttings or parts of a stem or reeds or spools or seedlings). A sugarcane seed is a dry monoseminal fruit or caryopsis that is formed from a single carpel, with the ovarian wall (pericarp) attached to the seminal cover (testa). The seeds are ovate, yellowish brown and very small, with a length of approximately 1 mm. However, in most commercial agriculture, stem sections are used instead of seeds.

Stem sections can be produced manually, p. ex. , cutting larger stem sections with a knife or machine. The resulting stem sections usually include several nodes per stem section. The term "nodule" means the part of the stem of a plant from which a leaf, branch or aerial root grows. After planting the stem sections, buds (or buds) may emerge at the position of each nodule. Then the buds can grow to obtain the crop plant. The speed of emergence or the speed at which the nodules produce buds to obtain crop plants is sometimes low in sugarcane.

To improve the likelihood that each section of planted stem will produce crop plants, the stem sections are usually planted with multiple nodules, eg. ex. , 3, 4 or 5 nodules per stem section. These stem sections with multiple nodes (or long stem sections) may have lengths of about 37, 40, or more. Normally, sections of stem with lengths of 40-50 cm are placed horizontally in furrows, which can be wide at ground level and deep (40-50 cm wide and 30-40 cm deep). Once planted, water, a fertilizer that includes nitrogen, and pesticides, such as herbicides and insecticides, can be sprayed onto the crop.

For various reasons, the Applicant wishes to improve the propagation, cultivation and biological effectiveness of existing sugarcane. For example, the Applicant wishes to provide at least one of the following advances: to improve the rate of nitrogen fixation in stems of sugarcane; reduce the amount of fertilizer that is applied to the stems of sugarcane; improve the emergence speed from mononodular stem sections; improve the emergence speed from multinodular stem sections; improve the growth rate of sugarcane plants; and improve the growth rate of sugarcane plants grown from stem sections.

The present technologies face any number of the previous deficiencies in conventional sugarcane cultivation and treatments. The present technologies can also deal with other deficiencies.

To summarize, in one example, the technology refers to a method for treating sugarcane that comprises injecting a mixture that includes bacteria in a stem section. In another example, the technology refers to a method for growing sugarcane that involves planting a section of treated stem. In another example, the technology refers to a sugarcane propagation system comprising a stem section defining a channel, and including a mixture that includes bacteria located within the channel.

In the previous compendium, it is intended to summarize certain embodiments of the present invention. In the figures and the detailed description that follows, systems, methods and mixtures will be explained in more detail. However, it will be evident that the detailed description is not intended to limit the present invention, the scope of which will be duly determined by the appended claims. The present invention relates to methods for treating sugarcane, methods for growing sugarcane and systems for propagating sugarcane.

Figures la and Ib illustrate a side view and a front view, respectively, of an example of a stem section 2 before a treatment has been applied. Stem section 2 was prepared by cutting a stem of sugar cane to the desired length. The Figure best illustrates the nodule 4 and the epidermis 6. Figure Ib best illustrates the exposed vascular bundles (HVE) 8 in a section of the stem section. The term "HVE", as used herein, may include the cross section of the stem section, including the xylem and phloem of the vascular bundles, as well as the cord and cortex. The opposite end of the cane cut 2 will have similar HVE. In other examples, the stem sections may include more nodules, e.g. eg, 2, 3, 4, 5, 6, etc. Analogously, the length of the treated stem sections may vary. For example, the stem sections may have a length comprised in a range selected from at least one of the following: from 2 to 60 cm, from 2.5 to 50 cm, from 2.5 to 40 cm, from 2.5 to 30 cm, from 2.5 at 20 cm, 2.5 to 15 cm, 2.5 to 10 cm, and 3 to 7 cm.

The treatment involves obtaining a stem section with at least one nodule and HVE, p. ex. , section of stem 2, and inject a mixture that includes nitrogen-fixing bacteria in the stem section. The stem sections will normally be obtained by cutting stems of the sugar cane in the desired stem sections. Obtaining also includes receiving or acquiring stem sections generated by others.

Figure 2 illustrates a plurality of sections of stem 12 with HVE 14, which have received injections in channels 16. In this example, the channeling and injections were performed with a single needle that penetrated and injected into the HVE. However, the injection was performed in several ways and at several points. For example, any number of needles can be used to penetrate a section of stem and inject the mixture into the stem section. In another example, the injection will be done with 2, 3, 4, 5, 6, 7, 8, 9, 10 or more needles in the HVE. In another example, the injection can be carried out through the epidermis with any number of needles, for example, at any of the points 20 in a larger stem section 22. The channels can be axial or not with respect to the length of the stem section. For example, the channels 16 are considered axial with respect to the length of the stem section. The channels formed through the epidermis will normally be considered non-axial.

When needles are used, the size of the needles may vary. For example, when used for penetration and injection, the diameter of the needles may be in a range of about 0.1 to about 5 mm, more usually about 0.1 to about 2 mm. The wall thickness can be in a range of about 0.05 to about 0.4 mm, more usually about 0.05 to about 0.1 mm. The depth of penetration of the needles can vary analogously. In one example, a needle is made to penetrate to a depth of at least 5 mm. In another example, a needle is made to penetrate to a depth of at least 10 mm. In many cases, the needles can be removed slightly, e.g. ex. , 1 mm, 2 mm, 3 mm, 4 mm, 5 mm or more, before the injection to create in this way a larger cavity in the stem section in which the mixture can be received. The volumes of the channels may vary as required, for example, volumes may range from 0.2 to 1.5 mL.

In other examples, there may be a defined channel in the stem section, p. ex. , in the HVE or that extends through the epidermis, in other ways. The channels can be defined with a corer, a drill bit, a reamer, etc. In such examples, injections can be performed in various ways, e.g. ex. , with a syringe, pipette, needle, etc., or any other suitable device to introduce the mixture into the channel. For more viscous mixtures, the injection can be done with other tools, p. ex. , A spatula.

The mixture injected into the stem section includes a concentration of nitrogen-fixing bacteria. The bacteria can be selected from at least one of the genera: Gluconacetobacter, Herbaspirilum, Azospirilum and Burkholderia. In many examples, the mixture will possess nitrogen fixing bacteria selected from at least two, at least three and at least all the genera used as an example. In addition, some examples may include multiple species within one or more of the genera, for example, at least two Herbaspirilum species. Illustrative species include any of the following: Gluconacetobacter diazotrophicus, Herbaspirilum seropedicae, Herbaspirilum rubrisubalbicans, Azospirilum amazonense and Burkholderia tropica.

The concentration of nitrogen-fixing bacteria and application rates may vary. For example, the mixtures can have a concentration in the range of 105 to 109 cfu / mL. In a somewhat similar way, the application rates may vary. The mixtures can be injected to apply the nitrogen-fixing bacteria at rates in the range of 105 to 109 cfu per stem section, in another example, from 2,108 to 4,108 cfu per stem section. Illustrative volume ranges include from 0.2 to 1 mL per stem section, in another example, 0.2 to 0.5 mL per stem section. In other cases, different concentrations, application rates or application volumes may be desired.

The mixtures may also include an organic carbon source for the bacteria, e.g. ex. , yeast extract or mannitol, as well as other micronutrients. In some situations, the mixture may include grass, for example, to provide substrate or micronutrients for the bacteria. In some examples, the mixture will be a minimum nitrogen medium to thereby inhibit the growth of bacteria other than nitrogen fixers in the mixture. Such modalities may be useful, for example, for storing and transporting mixtures or for facilitating the establishment of nitrogen-fixing populations. The minimum nitrogen medium includes media not containing nitrogen, e.g. ex. , Burke and Ashbey media, as well as means with nitrogen levels low enough to reduce the biological effectiveness of bacteria that are not perceptibly nitrogen fixers.

One of the advantages of some examples of current technology is that it allows the injection and absorption of nitrogen-fixing bacteria without the need to dry the stem section before injection. The Applicant believes that reducing drying will improve emergency speeds, in particular, for shorter stem sections, e.g. ex. , those that have 1 nodule. In many examples, the injection will be made when the stem section has a percentage of weight loss, with respect to a section of freshly cut stem, selected from at least one of the following: less than 30%, less than 25% , less than 20%, less than 15%, less than 10% and less than 5%. Appropriate levels can be achieved for the percentage of weight loss by performing the injection in at least one of the following periods: 24 hours, 18 hours, 16 hours, 14 hours, 12 hours, 10 hours, 8 hours, 6 hours, 4 hours , 2 hours and 1 hour. The methods may also include coating the HVE with a moisture sealing barrier, for example, to further reduce water loss. In many examples, the channel within the stem section can also create an environment with more stable moisture conditions, nutrient content and temperature for the bacteria in the mix, and is believed to encourage a more systemic or localized establishment fast and healthy bacterial populations that fix nitrogen.

The present invention also relates to methods for growing sugarcane which may include planting a stem section that has been treated in any of the ways described above. In one example, a method includes obtaining a stem section with at least one node and exposed vascular bundles (HVE). A mixture including a concentration of nitrogen-fixing bacteria in the stem section is injected. Next, the section of treated stem is planted. The methods may also comprise planting additional stem sections that have been treated as described above. When additional stem sections are planted, the number of nodes per linear meter can be in at least one of the following ranges: between 2 and 200, between 2 and 100, between 4 and 75, and between 10 and 40.

The current invention also refers to sugarcane propagation systems. The sugarcane propagation systems include a section of stem treated according to any of the methods described above. In one example, a system includes an undercut section with at least one node and exposed vascular bundles (HVE). The stem section defines a channel created by, for example, a needle. A mixture containing a concentration of nitrogen-fixing bacteria in the channel is introduced.

Using the systems, methods or mixtures described herein, the Applicant believes that any of various benefits in the cultivation of sugarcane will be achieved. For example, the Applicant believes that at least one of the following advances can be achieved: improve the rate of nitrogen fixation in stems of sugarcane; reduce the amount of fertilizer that is applied to the stems of sugarcane; improve the emergence speed from mononodular stem sections; improve the emergence speed from multinodular stem sections; improve the growth rate of sugarcane plants; and improve the growth rate of sugarcane plants grown from stem sections. It is not intended that this list is limiting and other benefits can be obtained, p. ex. , greater resistance to pests, etc.

In the above description numerous features and advantages have been set forth together with structural and functional details. However, the invention is illustrative only and changes in details can be made within the principle of the invention.

Although the ranges and numerical parameters that establish the broad scope of the invention are approximations, the numerical values mentioned in the specific examples are indicated as accurately as possible. However, any numerical value inherently contains certain errors that are necessarily the result of the standard deviation detected in the measurements of the respective tests. Moreover, it should be understood that all the ranges described herein comprise each and every one of the subintervals that they contain, and each number comprised between the limits of the intervals. For example, it should be considered that an indicated interval of "between 1 and 10" contains each and every one of the subintervals comprised (inclusive) between the minimum value 1 and the maximum value 10; that is, all subintervals that start with a minimum value greater than or equal to l, p. eg, from l to 6.1, and end with a maximum value less than or equal to 10, p. ex. , from 5.5 to 10, as well as all the intervals that begin and end between the limits of the interval, p. ex. , between 2 and 9, between 3 and 8, between 3 and 9, between 4 and 7, and finally, to each number 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 contained in the interval. It should be noted that in addition, the singular forms "a", "an", "the" and "the", as used in this description, include the plural referents unless they are expressly and unequivocally limited to a referent.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A method to treat a sugar cane characterized in that it comprises: get a stem section with at least one nodule and vascular exposed beams (HVE); and Inject a mixture into the stem section, where the mixture includes a concentration of nitrogen-fixing bacteria.

2. The method according to claim 1, characterized in that the stem section has not been dried before injection.

3. The method according to claim 1, characterized in that the stem section has a percentage of weight loss, with respect to a section of freshly cut stem, selected from at least one of the following: less than 30%, less than one 25%, less than 20%, less than 15%, less than 10% and less than 5%.

4. The method according to claim 1, characterized in that the sugar cane is a species of Saccharum.

5. The method according to claim 4, characterized in that the Saccharum species is selected from at least one of the following: S. arundinaceu, S. bengalense, S. edule, S. unja, S. officinarum, S. procerum, S. Ravennae, S. robustum, S. sinense and S. spontaneum.

6. The method according to claim 1, characterized in that the stem section has a number of nodes selected from 1, 2, 3, 4, 5 and 6.

7. The method according to claim 1, characterized in that the stem section has only one nodule.

8. The method according to claim 1, characterized in that the stem section has a length comprised in a range selected from at least one of the following: between 2 and 60 cm, between 2.5 and 50 cm, between 2.5 and 40 cm, between 2.5 and 30 cm, between 2.5 and 20 cm, between 2.5 and 15 cm, between 2.5 and 10 cm, and between 3 and 7 cm.

9. The method according to claim 1, characterized in that the mixture is injected into the HVE of the stem section.

10. The method according to claim 1, characterized in that it also includes penetrating the HVE with at least one needle before injection.

11. The method according to claim 10, characterized in that the needle it is penetrated to a depth of at least 5 mm, has a diameter in the range of between about 0.1 and about 5 mm; Y it has a wall thickness in the range of between about 0.05 and about 0.4 mm.

12. The method according to claim 10, characterized in that the needle is made to penetrate to a depth of at least 10 mm and then it is extracted at least 1 mm before the injection to thereby create a cavity in the stem section for the mixture.

13. The method according to claim 9, characterized in that it also includes defining a channel in the HVE before the injection.

14. The method according to claim 1, characterized in that the nitrogen fixing bacteria are selected from at least one of the following genera: Gluconacetobacter, Herbaspirilum, Azospirilum and Burkholderia.

15. The method according to claim 1, characterized in that the nitrogen fixing bacteria are selected from at least two of the following genera: Glucorzacetojbacfcer, Herbaspirilum, Azospirilum and Burkholderia.

16. The method according to claim 1, characterized in that the nitrogen fixing bacteria are selected from at least three of the following genera: Gluconacetobacter, Herbaspirilum, Azospirilum and Burkholderia.

17. The method according to claim 1, characterized in that the nitrogen fixing bacteria are selected from each of the genera: Gluconacetobacter, Herbaspirilum, Azospirilum and Burkholderia.

18. The method according to claim 17, characterized in that the nitrogen-fixing bacteria include at least two Herbaspirilum species.

19. The method according to claim 17, characterized in that the genus Gluconacetobacter includes Gluconacetojbacter diazotrophicus, the genus Herbaspirilum includes at least one of the species Herbaspirilum seropedicae and Herbaspirilum rubrisubalbicans, the genus Azospirilum includes Azospirilum amazonense; and the Burkholderia genus includes Burkholderia tropico.

20. The method according to claim 1, characterized in that the concentration of nitrogen-fixing bacteria is in the range of 105 to 109 cfu / mL.

21. The method according to claim 1, characterized in that the mixture is injected to apply the nitrogen-fixing bacteria at rates in the range of 105 to 109 cfu per stem section.

22. The method according to claim 1, characterized in that the volume of mixture applied to the stem section is in the range of 0.2 to 1 mL.

23. The method according to claim 1, characterized in that the mixture is a minimum means of nitrogen to thereby inhibit the growth of bacteria that are not nitrogen fixers in the mixture.

24. The method according to claim 1, characterized in that the mixture also includes at least one of the following components: a source of organic carbon for bacteria and micronutrients.

25. The method according to claim 1, characterized in that it also includes coating the HVE with a moisture sealing barrier.

26. The method according to claim 1, characterized in that the stem section is obtained by cutting a stem of the sugarcane and where the stem section is injected in at least one term of the following: less than 24 hours, less than 12 hours and less than 6 hours after cutting the stem of the sugarcane.

27. A method for growing sugarcane, characterized in that it comprises the method of: get a stem section with at least one nodule and vascular exposed beams (HVE); injecting a mixture into the stem section, where the mixture includes a concentration of nitrogen-fixing bacteria; Y plant the injected stem section.

28. The method according to claim 27, characterized in that the stem section has not been dried before injection.

29. The method according to claim 27, characterized in that the stem section has a percentage of weight loss, with respect to a cutting of freshly cut sugar cane, selected from at least one of the following: less than 30%, less than 25%, less than 20%, less than 15%, less than 10% and less than 5%.

30. The method according to claim 27, characterized in that the sugar cane is a species of Saccharum.

31. The method according to claim 27, characterized in that the stem section has a number of nodes selected from at least 2, at least 3, at least 4, at least 5 and at least 6.

32. The method according to claim 27, characterized in that the stem section has only one nodule.

33. The method according to claim 27, characterized in that the stem section has a selected length that is comprised between at least one of the following ranges: from 2 to 60 cm, from 2.5 to 50 cm, from 2.5 to 40 cm, from 2.5 to 30 cm, 2.5 to 20 cm, 2.5 to 15 cm, 2.5 to 10 cm, and 3 to 7 cm.

34. The method according to claim 27, characterized in that the mixture is injected into the HVEs of the stem section.

35. The method according to claim 34, characterized in that it also includes penetrating the HVE with at least one needle before injection.

36. The method according to claim 35, characterized in that the needle it is penetrated to a depth of at least 5 mm, has a diameter in the range of between about 0.1 and about 5 mm; Y it has a wall thickness in the range of between about 0.05 and about 0.4 mm.

37. The method according to claim 35, characterized in that the needle is made to penetrate to a depth of at least 10 mm and then it is extracted at least 1 mm before the injection to thereby create a cavity in the stem section for the mixture.

38. The method according to claim 34, characterized in that it also includes defining a channel in the HVE before the injection.

39. The method according to claim 27, characterized in that the nitrogen-fixing bacteria are selected from at least one of the following genera: Gluconacetobacter, Herbaspirilum, Azospirilum and Burkholderia.

40. The method according to claim 27, characterized in that the nitrogen fixing bacteria are selected from at least two of the following genera: Gluconacetobacter, Herbaspirilum, Azospirilum and Burkholderia.

41. The method according to claim 27, characterized in that the nitrogen fixing bacteria are selected from at least three of the following genera: Gluconacetobacter, Herbaspirilum, Azospirilum and Burkholderia.

42. The method according to claim 27, characterized in that the nitrogen fixing bacteria are selected from each of the genera: Gluconacetobacter, Herbaspirilum, Azospirilum and Burkholderia.

43. The method according to claim 27, characterized in that the nitrogen-fixing bacteria include at least two Herbaspirilum species.

44. The method according to claim 42, characterized in that the genus GluconacetOjbac er includes Gluconacetobacter diazotrophicus, the genus Herbaspirilum includes at least one of the species Herbaspirilum seropedicae and Herbaspirilum rubrisubalbicans, the genus Azospirilum includes Azospirilum amazonense; and the Burkholderia genus includes Burkholderia tropico.

45. The method according to claim 27, characterized in that the concentration of nitrogen-fixing bacteria is in the range of between 105 and 109 cfu / mL.

46. The method according to claim 27, characterized in that the mixture is injected to apply the nitrogen-fixing bacteria at rates in the range of 105-109 cfu per stem section.

47. The method according to claim 27, characterized in that the volume of mixture applied to the stem section is in the range of 0.2 to 1 mL.

48. The method according to claim 27, characterized in that the mixture is a minimum means of nitrogen to thereby inhibit the growth of bacteria other than nitrogen fixers in the mixture.

49. The method according to claim 27, characterized in that the mixture also includes at least one of the following components: a source of organic carbon for bacteria and micronutrients.

50. The method according to claim 27, characterized in that it also includes coating the HVE with a moisture sealing barrier before planting them.

51. The method according to claim 27, characterized in that the stem section is obtained by cutting a stem from the sugar cane and where the stem section is injected in at least one of the following periods: less than 24 hours, less than 12 hours and less than 6 hours after cutting the stem of the sugarcane.

52. The method according to claim 27, characterized in that it also includes obtaining, injecting and planting a plurality of additional stem sections.

53. The method according to claim 52, characterized in that the plurality of additional stem sections are planted so that the number of nodes per linear meter is in the selected range between at least one of the following: from 2 to 200, 2 to 100, from 4 to 75, and from 10 to 40.

54. A sugarcane propagation system characterized in that it comprises: a section of stem with at least one node and exposed vascular bundles (HVE), where the stem section defines a channel, and a mixture located inside the channel, where the mixture includes a concentration of nitrogen-fixing bacteria.

55. The system according to claim 54, characterized in that the stem section has a number of nodes selected between 1, 2, 3, 4, 5 and 6.

56. The system according to claim 54, characterized in that the stem section has only one nodule.

57. The system according to claim 54, characterized in that the stem section has a length comprised in a range selected from at least one of the following: from 2 to 60 cm, from 2.5 to 50 cm, from 2.5 to 40 cm, 2.5 to 30 cm, 2.5 to 20 cm, 2.5 to 15 cm, 2.5 to 10 cm, and 3 to 7 cm.

58. The system according to claim 54, characterized in that the channel and the stem section are axial.

59. The system according to claim 54, characterized in that the channel is formed with a needle.

60. The system in accordance with the claim 59, characterized in that the channel includes an entry defined within the HVE.

61. The system according to claim 54, characterized in that the channel has a volume comprised in the range of 0.2 to 1.5 mL.

62. The system according to claim 54, characterized in that the mixture includes from 105 to 109 cfu of nitrogen-fixing bacteria.

63. The system according to claim 54, characterized in that the mixture is a minimum means of nitrogen to inhibit in this way the growth of bacteria that are not nitrogen-fixing in the mixture.

64. The system according to claim 54, characterized in that the mixture also includes at least one of the following components: a source of organic carbon for bacteria and micronutrients.

65. The system according to claim 54, characterized in that it also includes a moisture sealing barrier that covers at least the HVE.