Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, the problem to be solved by the present invention is to provide a method for multi-head tomato seedling raising that improves tomato yield.
A tomato multi-head seedling raising method comprises the following steps:
s1, removing growing points of a main rod: when the tomato seedlings grow to three leaves and one heart, namely three true leaves and one growing point, removing the growing point of the main stem at a position 0.5-1 cm above the axilla of the third true leaf from bottom to top; after the growing points of the main stems are removed, smearing and covering the wound by using a wound healing agent to prevent tomato seedlings from infecting diseases;
s2, controlling the area proportion of the leaves: regulating and controlling the leaf area of the three true leaves, and removing the leaves of the main rod from bottom to top according to a proportion, so that the processes of the growing points at the armpits of the three true leaves are consistent during the field planting of the seedlings;
s3, regulating and controlling technical management: in the process of seedling culture, the environmental temperature in the daytime is controlled to be 21-28 ℃, the temperature at night is controlled to be 15-19 ℃, and the solar radiation degree is 300-400W/m 2 And the relative air humidity interval is 60-80%, and tomato branches germinate and grow to obtain the multi-head tomato seedlings.
Preferably, the removal rate of the blades from the main rod from the bottom to the top in step S2 is 0%, 30%, or 70%, respectively.
Preferably, the solar radiation degree in the step S3 changes along with the seedling growth quantization index; the seedling growth quantization indexes are three leaves, one heart (plant height: 10-15 cm), three growth points (plant height: 15-20 cm) and three-head seedling forms (plant height: 20-30 cm) in sequence, and the corresponding solar radiation degree is 300W/m in sequence 2 、350W/m 2 、400W/m 2 。
When the gardening operation of removing the growing point of the main rod is carried out, tomato seedlings can be wounded and flowed, nutrient substances conveyed from the bottom of the root to the top of the root overflow from the incision, the resistance of the tomato seedlings is reduced, and the tomato seedlings are very easy to infect diseases. In the prior art, a mixture formed by hydrated lime, an additive and water is smeared on a wound to promote healing, or polymers such as paint and the like are used for covering the wound to inhibit the exosmosis of plant tissue fluid and seal the wound to prevent infection of diseases. When the mixture formed by the fillers such as hydrated lime, yellow mud and the like and water is applied to a wound, the defect of poor sealing performance is often caused after the mixture is dried, and the surface structure is loose and porous due to the water loss of the fillers, so that the bonding performance with the wound is reduced, and the probability of disease infection is increased. Polymers such as paint and rosin are adopted to paint the wound, so that poor fitting caused by water loss can be well solved, but volatile substances in the paint and heavy metal elements introduced in the processing process are not beneficial to plant growth, the dried paint is difficult to degrade, and normal ventilation and water exchange of plants are influenced by adhesion to the surfaces of soil and plants. Tomato seedlings are sensitive to the environment and have weak resistance, and the use of the paint can have adverse effects on the tomato seedlings in chemical and physical aspects, and the tomato seedlings can suffer from symptoms such as wilting and withering in severe cases.
Based on the technical problems, the invention optimizes and prepares the degradable wound healing agent which has good adhesion performance and promotes wound polymerization. The wound healing agent takes polyethylene glycol with a flexible chain, methyl propylene glycol and 2, 2-dimethylolpropionic acid as raw materials, and forms a ductile molecular long chain by the reaction of hydroxyl and carboxyl with isocyanic acid radical of dicyclohexylmethane-4, 4' -diisocyanate. The molecular chains are connected by amido bonds or urea bonds, so that the biodegradable polyurethane has biodegradability; the polymer molecular chain end, phenylalanine and histidine are continuously combined through the reaction of isocyanic acid radical and amino group, two amino acids are introduced into the molecule, and the polymer with good wetting and attaching performances is obtained. The polymer is subsequently mixed with degradable porous xanthan gum in an aqueous dispersion to obtain the wound healing agent.
Preferably, the preparation method of the wound healing agent is as follows:
m1, mixing polyethylene glycol and methyl propylene glycol in an oxygen-free environment to obtain a uniform reaction mixture; adding dicyclohexylmethane-4, 4' -diisocyanate and a catalyst into the reaction mixture, and carrying out a first-stage polymerization reaction to obtain a first-stage polymerization product for later use;
m2, continuously adding 2, 2-dimethylolpropionic acid into the first-stage polymerization product in an oxygen-free environment to carry out second-stage polymerization reaction; after the second-stage polymerization reaction is finished, cooling the reaction product to normal temperature, adding dichloromethane, uniformly stirring, and adjusting the pH value of the solution to be neutral to obtain a second-order polymerization product for later use;
m3, continuously adding compound amino acid into the second-order polymerization product in an oxygen-free environment, carrying out a third-stage polymerization reaction, and removing dichloromethane through reduced pressure distillation after the reaction is finished to obtain a polymerization final product for later use;
m4, dissolving xanthan gum in water to obtain a xanthan gum aqueous solution; adding methacrylic anhydride into the xanthan gum aqueous solution, uniformly mixing and starting to react; freeze-drying and crushing the reaction product to obtain porous gel for later use;
and M5, mixing the final polymerization product, the porous gel and water, and stirring to form uniformly dispersed viscous liquid, wherein the viscous liquid is the wound healing agent.
Specifically, the preparation method of the bleeding wound healing agent comprises the following steps of:
m1, mixing 6-10 parts of polyethylene glycol and 0.2-0.5 part of methyl propylene glycol under the condition of heating in an oxygen-free environment to obtain a uniform reaction mixture; adding 2-5.5 parts of dicyclohexylmethane-4, 4' -diisocyanate and 0.1-0.3 part of dibutyltin dilaurate into the reaction mixture, and carrying out first-stage polymerization reaction to obtain a first-stage polymerization product for later use;
m2, continuously adding 1.5-3.5 parts of 2, 2-dimethylolpropionic acid into the first-stage polymerization product in an oxygen-free environment to perform second-stage polymerization reaction; after the second-stage polymerization reaction is finished, cooling the reaction product to normal temperature, adding 20-50 parts of dichloromethane, uniformly stirring, and adjusting the pH value of the solution to be neutral to obtain a second-order polymerization product for later use;
m3, continuously adding 0.6-1.8 parts of compound amino acid into the second-order polymerization product in an oxygen-free environment, cooling, carrying out a third-stage polymerization reaction, and removing dichloromethane through reduced pressure distillation after the reaction is finished to obtain a final polymerization product for later use;
m4, dissolving 0.5-1 part of xanthan gum in 50-100 parts of water to obtain a xanthan gum aqueous solution; adding 1-3.5 parts of methacrylic anhydride into the xanthan gum aqueous solution, uniformly mixing, and heating to start reaction; freeze-drying and crushing the reaction product to obtain porous gel for later use;
m5, mixing 3-6 parts of the final polymerization product, 0.5-1.5 parts of porous gel and 25-100 parts of water, and stirring to form uniformly dispersed viscous liquid, wherein the viscous liquid is the wound healing agent.
Preferably, the polyethylene glycol in step M1 has an average molecular weight of 200 to 600.
Preferably, the temperature of the mixing under heating in the step M1 is 85-95 ℃ and the mixing time is 0.5-2 h.
Preferably, the reaction temperature of the first-stage polymerization reaction in the step M1 is 75-90 ℃, and the reaction time is 2-5 h.
Preferably, the reaction temperature of the second stage polymerization reaction in the step M2 is 65-80 ℃, and the reaction time is 0.5-2 h.
Preferably, in the step M3, the compound amino acid is phenylalanine and histidine at a mass ratio of 1.5-4: 1, and (b) a mixture.
Preferably, the reaction temperature of the third stage polymerization reaction in the step M3 is 0-4 ℃, and the reaction time is 0.5-2 h.
Preferably, the reaction temperature of the reaction in the step M4 is 55-70 ℃, and the reaction time is 1.5-4 h.
Preferably, the stirring treatment rate in the step M5 is 750-1500 rpm, and the treatment time is 0.5-1 h.
The molecular chain of the wound healing agent has good ductility, macroscopically shows good fluidity, and can be spread on the wound to form a protective film. With the drying of the moisture, the wound healing agent is gradually solidified and attached to the wound, so that the wound and the external environment are effectively isolated, and the invasion of diseases is prevented. With the healing of tomato sprout wounds, amido bonds or urea bonds at the molecular chain ends of the wound healing agent are degraded to release phenylalanine and histidine. Phenylalanine can promote the synthesis of phenylalkane compounds such as lignin; histidine can provide a precursor of carbon skeleton hormone, and is also a catalytic enzyme for cytokinin synthesis, and cytokinin is closely related to the formation of vascular tissues and can induce the generated callus. Under the influence of the two amino acids, the healing of the wound surface is accelerated, and the tomato seedlings can survive conveniently. After the wound is completely healed, the wound healing agent gradually falls off from the surface along with degradation, and the urea degradation can provide a nitrogen source for the growth of crops and can promote the growth of the crops to a certain extent.
On the basis of the common general knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.
The introduction and the function of part of raw materials in the formula of the invention are as follows:
phenylalanine: has a chemical formula of C 9 H 11 NO 2 The molecular weight is 165.19, the systematic name is 2-aminophenylpropionic acid which is one of alpha-amino acids, is white crystal or crystalline powder solid at normal temperature, is sublimed under reduced pressure, is soluble in water and is insoluble in methanol, ethanol and ether. Alanine can promote the synthesis of phenylalanines such as lignin.
Histidine: an alpha-amino acid of the formula C 6 H 9 N 3 O 2 And the molecular weight is 155. Histidine provides a precursor for carbon skeleton hormones, and is also a catalytic enzyme for cytokinin synthesis.
Xanthan gum: the microbial extracellular polysaccharide with wide effect is produced by taking carbohydrates as main raw materials of the xanthomonas campestris through fermentation engineering. The polysaccharide has unique rheological property, good water solubility, heat and acid-base stability and good compatibility with various salts, and is the microbial polysaccharide which has the largest production scale and extremely wide application in the world at present.
The invention has the beneficial effects that:
compared with the prior art, the method has the advantages that the growing points of the main rod are removed, the leaf area proportion is controlled, the cultivation environment of the tomato seedlings is accurately controlled, auxin and cytokinin generated by the leaves are transferred to leaf axils corresponding to the leaves, and the germination of tomato branches is promoted; the invention promotes the seedlings to germinate and grow at the axilla of the true leaves, shortens the time of the seedlings in the seedling stage, prolongs the harvesting period of the greenhouse planting end, and promotes the yield of the tomatoes in unit area.
Compared with the prior art, the wound healing agent is used in the step of removing the growing points of the main rod, has good fluidity, can be spread on the surface and solidified to form a protective film when being smeared on the wound, effectively isolates the wound from the external environment, and prevents the invasion of diseases.
Compared with the prior art, the wound healing agent used in the invention has biodegradability, and along with the healing of the tomato sprout wound, the amido bond or urea bond at the molecular chain end of the wound healing agent is degraded to release phenylalanine and histidine, thereby promoting the healing of the wound and forming callus, and being beneficial to the survival of the tomato sprout.
Detailed Description
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.
Some raw material parameters in the comparative examples and examples of the invention are as follows:
dicyclohexylmethane-4, 4' -diisocyanate, CAS No.: 5124-30-1;
polyethylene glycol, PEG-200, available from Jinan Xiangfeng Wei industries chemical Co.
The tomato variety used in the test is medium vegetable No. 4, and the seedbed and seeds need to be disinfected before planting. The number of tomato seedlings in each group is 50, and the tomato seedlings are treated and cultivated according to different seedling raising methods of each embodiment and a control example. In the seedling raising process, recording the number of plants with the wound of the seedling healed after the growth point of the main rod is removed, and obtaining the healing rate; for the healed tomato seedlings, observing and recording the callus formation time every 0.5d, and calculating the average time, wherein the result is accurate to 0.5d; and recording the total time from the beginning of seedling culture to the germination of the tomato branches, calculating the average time, and averaging the results until the time is accurate to 0.5d.
Example 1
A tomato multi-head seedling is obtained by cultivating the following method:
s1, removing growing points of a main rod: when the tomato seedlings grow to three leaves and one heart, namely three true leaves and one growing point, removing the growing point of the main stem at a position 0.5cm above the axilla of the third true leaf from bottom to top;
s2, controlling the area proportion of the leaves: regulating the leaf area of the three true leaves, and removing the leaves counted from bottom to top of the main rod according to the proportion of 0%, 30% and 70% respectively, so that the processes of the growing points at the axilla of the three true leaves are consistent during the field planting of the seedlings;
s3, regulating and controlling technical management: in the process of seedling culture, the daytime environment temperature is controlled to be 28 ℃, the nighttime temperature is controlled to be 15 ℃, and the solar radiation degree is controlled to be 400W/m 2 And the relative air humidity interval is 60%, and the tomato branches germinate and grow to obtain the multi-head tomato seedlings.
In the step S3, the solar radiation degree changes along with the seedling growth quantization index; the seedling growth quantization indexes are three leaves, one heart, three growth points and three seedling shapes are established in sequence, and the corresponding solar radiation degree is 300W/m in sequence 2 、350W/m 2 、400W/m 2 。
In the embodiment, the healing number of the wounds is 37 in total after the main stem growing points of the tomato seedlings are removed, and the healing rate is 74%; the average callus formation time was 9.5d; the average time length in the seedling stage is 26d.
Example 2
A tomato multihead seedling is obtained by cultivating the following method:
s1, removing growing points of a main rod: when the tomato seedlings grow to three leaves and one heart, namely three true leaves and one growing point, removing the growing point of the main stem at the position 0.5cm above the axilla of the third true leaf from bottom to top; after the growing points of the main stems are removed, smearing and covering the wound by using a wound healing agent to prevent tomato seedlings from infecting diseases;
s2, controlling the area ratio of the leaves: regulating and controlling the leaf areas of the three true leaves, and removing the leaves from the bottom to the top of the main rod according to the proportion of 0%, 30% and 70% respectively, so that the growth points of the axilla of the three true leaves are consistent in process during the field planting of the seedlings;
s3, regulating and controlling technical management: in the process of seedling culture, the daytime environment temperature is controlled to be 28 ℃, the nighttime temperature is controlled to be 15 ℃, and the solar radiation degree is controlled to be 400W/m 2 And the relative air humidity interval is 60%, and the tomato branches germinate and grow to obtain the multi-head tomato seedlings.
In the step S3, the solar radiation degree changes along with the seedling growth quantization index; the seedling growth quantization indexes are three leaves, one heart, three growth points and three seedling shapes are established in sequence, and the corresponding solar radiation degree is 300W/m in sequence 2 、350W/m 2 、400W/m 2 。
The preparation method of the wound healing agent comprises the following steps:
m1, under the protection of nitrogen, mixing 6kg of PEG-200 and 0.2kg of methyl propylene glycol at 85 ℃ for 1h to obtain a uniform reaction mixture; adding 2.5kg of dicyclohexylmethane-4, 4' -diisocyanate and 0.1kg of dibutyltin dilaurate into the reaction mixture, carrying out first-stage polymerization reaction, and reacting at 75 ℃ for 3.5h to obtain a first-stage polymerization product for later use;
m2, under the protection of nitrogen, continuously adding 1.5kg of 2, 2-dimethylolpropionic acid into the first-stage polymerization product to perform second-stage polymerization reaction, and reacting for 1.5h at 70 ℃; after the second-stage polymerization reaction is finished, cooling the reaction product to normal temperature, adding 50kg of dichloromethane, uniformly stirring, and adjusting the pH value of the solution to be neutral to obtain a second-order polymerization product for later use;
m3, under the protection of nitrogen, continuously adding 0.9kg of phenylalanine into the second-order polymerization product, cooling to 4 ℃, and carrying out a third-stage polymerization reaction for 0.5h; after the reaction is finished, removing dichloromethane through reduced pressure distillation to obtain a final polymerization product for later use;
m4, dissolving 0.5kg of xanthan gum in 100kg of water to obtain a xanthan gum aqueous solution; adding 1kg of methacrylic anhydride into the xanthan gum aqueous solution, uniformly mixing, heating to 65 ℃ and starting to react for 2.5 hours; freeze drying and crushing the reaction product to obtain porous gel for later use;
m5, 4.5kg of the final polymerization product, 0.5kg of the porous gel and 100kg of water were mixed and stirred at 1250rpm for 0.5h to form a uniformly dispersed viscous liquid, which was the wound healing agent.
In the embodiment, the healing rate of the wounds is 86 percent, wherein the total number of the healed wounds is 43 after the main rod growing points of the tomato seedlings are removed; the average callus formation time was 6d; the average time length in the seedling stage is 24.5d.
Example 3
A tomato multihead seedling is obtained by cultivating the following method:
s1, removing growing points of a main rod: when the tomato seedlings grow to three leaves and one heart, namely three true leaves and one growing point, removing the growing point of the main stem at a position 0.5cm above the axilla of the third true leaf from bottom to top; after the growing points of the main stems are removed, smearing and covering the wound by using a wound healing agent to prevent tomato seedlings from infecting diseases;
s2, controlling the area ratio of the leaves: regulating and controlling the leaf areas of the three true leaves, and removing the leaves from the bottom to the top of the main rod according to the proportion of 0%, 30% and 70% respectively, so that the growth points of the axilla of the three true leaves are consistent in process during the field planting of the seedlings;
s3, regulating and controlling technical management: in the process of seedling culture, the daytime environment temperature is controlled to be 28 ℃, the night temperature is controlled to be 15 ℃, and the solar radiation degree is controlled to be 400W/m 2 And the relative air humidity interval is 60%, and tomato branches germinate and grow to obtain the multi-head tomato seedlings.
In the step S3, the solar radiation degree changes along with the seedling growth quantization index; the seedling growth quantization indexes are three leaves, one heart, three growth points, three seedling forms and corresponding solar radiation degreesAre 300W/m in sequence 2 、350W/m 2 、400W/m 2 。
The preparation method of the wound healing agent comprises the following steps:
m1, under the protection of nitrogen, 6kg of PEG-200 and 0.2kg of methyl propylene glycol are mixed for 1 hour at 85 ℃ to obtain a uniform reaction mixture; adding 2.5kg of dicyclohexylmethane-4, 4' -diisocyanate and 0.1kg of dibutyltin dilaurate into the reaction mixture, carrying out first-stage polymerization reaction, and reacting at 75 ℃ for 3.5h to obtain a first-stage polymerization product for later use;
m2, under the protection of nitrogen, continuously adding 1.5kg of 2, 2-dimethylolpropionic acid into the first-stage polymerization product to perform second-stage polymerization reaction, and reacting for 1.5h at 70 ℃; after the second-stage polymerization reaction is finished, cooling the reaction product to normal temperature, adding 50kg of dichloromethane, uniformly stirring, and adjusting the pH value of the solution to be neutral to obtain a second-order polymerization product for later use;
m3, under the protection of nitrogen, continuously adding 0.9kg of histidine into the second-order polymerization product, cooling to 4 ℃, and carrying out a third-stage polymerization reaction for 0.5h; after the reaction is finished, removing dichloromethane through reduced pressure distillation to obtain a final polymerization product for later use;
m4, dissolving 0.5kg of xanthan gum in 100kg of water to obtain a xanthan gum aqueous solution; adding 1kg of methacrylic anhydride into the xanthan gum aqueous solution, uniformly mixing, heating to 65 ℃ and starting to react for 2.5 hours; freeze-drying and crushing the reaction product to obtain porous gel for later use;
m5, mixing 4.5kg of the final polymerization product, 0.5kg of the porous gel and 100kg of water, and stirring at 1250rpm for 0.5h to form a uniformly dispersed viscous liquid, which is the wound healing agent.
In the embodiment, the number of healed wounds after the main rod growing points of the tomato seedlings are removed is 45 in total, and the healing rate is 90%; the average callus formation time was 5.5d; the average time length in the seedling stage is 24d.
Example 4
A tomato multi-head seedling is obtained by cultivating the following method:
s1, removing growing points of a main rod: when the tomato seedlings grow to three leaves and one heart, namely three true leaves and one growing point, removing the growing point of the main stem at a position 0.5cm above the axilla of the third true leaf from bottom to top; after the growing points of the main stems are removed, smearing and covering the wound by using a wound healing agent to prevent tomato seedlings from infecting diseases;
s2, controlling the area proportion of the leaves: regulating and controlling the leaf areas of the three true leaves, and removing the leaves from the bottom to the top of the main rod according to the proportion of 0%, 30% and 70% respectively, so that the growth points of the axilla of the three true leaves are consistent in process during the field planting of the seedlings;
s3, regulating and controlling technical management: in the process of seedling culture, the daytime environment temperature is controlled to be 28 ℃, the nighttime temperature is controlled to be 15 ℃, and the solar radiation degree is controlled to be 400W/m 2 And the relative air humidity interval is 60%, and tomato branches germinate and grow to obtain the multi-head tomato seedlings.
In the step S3, the solar radiation degree changes along with the seedling growth quantization index; the seedling growth quantization indexes are three leaves, one heart, three growth points and three seedling forms, and the corresponding solar radiation degree is 300W/m 2 、350W/m 2 、400W/m 2 。
The preparation method of the bleeding injury healing agent comprises the following steps:
m1, under the protection of nitrogen, mixing 6kg of PEG-200 and 0.2kg of methyl propylene glycol at 85 ℃ for 1h to obtain a uniform reaction mixture; adding 2.5kg of dicyclohexylmethane-4, 4' -diisocyanate and 0.1kg of dibutyltin dilaurate into the reaction mixture, carrying out first-stage polymerization reaction, and reacting at 75 ℃ for 3.5h to obtain a first-stage polymerization product for later use;
under the protection of M2 and nitrogen, continuously adding 1.5kg of 2, 2-dimethylolpropionic acid into the first-stage polymerization product to perform second-stage polymerization reaction, and reacting at 70 ℃ for 1.5h; after the second-stage polymerization reaction is finished, cooling the reaction product to normal temperature, adding 50kg of dichloromethane, uniformly stirring, and adjusting the pH value of the solution to be neutral to obtain a second-order polymerization product for later use;
and M3, under the protection of nitrogen, continuously adding 0.9kg of compound amino acid into the second-order polymerization product, wherein the compound amino acid is phenylalanine and histidine in a mass ratio of 3.5:1, cooling to 4 ℃, and carrying out a third-stage polymerization reaction for 0.5h; after the reaction is finished, removing dichloromethane through reduced pressure distillation to obtain a final polymerization product for later use;
m4, dissolving 0.5kg of xanthan gum in 100kg of water to obtain a xanthan gum aqueous solution; adding 1kg of methacrylic anhydride into the xanthan gum aqueous solution, uniformly mixing, heating to 65 ℃ and starting reaction, wherein the reaction time is 2.5h; freeze-drying and crushing the reaction product to obtain porous gel for later use;
m5, 4.5kg of the final polymerization product, 0.5kg of the porous gel and 100kg of water were mixed and stirred at 1250rpm for 0.5h to form a uniformly dispersed viscous liquid, which was the wound healing agent.
In the embodiment, the healing number of the wounds is 49 after the main stem growing points of the tomato seedlings are removed, and the healing rate is 98%; the average callus formation time was 4.5d; the average time length in the seedling stage is 23d.
Comparative example 1
The main stems and the true leaves of the tomato seedlings of the comparative example were not treated, and the environment for growing the seedlings was consistent with that of example 1. The average length of the control in the seedling stage was 34.5 days.
Comparative example 2
The processing method and the cultivation environment of the tomato multi-head seedlings in the comparative example are basically the same as those in the example 4, and the differences are only that: the wound healing agent used in this comparative example was a gray salt protectant used in the prior art; the ash salt protective agent is prepared by uniformly mixing 1kg of hydrated lime, 0.05kg of sodium chloride and 1kg of water.
In the comparative example, the number of healed wounds of the tomato seedlings after the main stem growing points are removed is 40 in total, and the healing rate is 80%; the average callus formation time was 7.5d; the average time length in the seedling stage is 25.5d.
Comparative example 3
The treatment method and cultivation environment of the tomato multi-head seedlings in the comparative example are basically the same as those in example 4, and the differences are only that: the bleeding healing agent used in this comparative example was a rosin boiled oil agent used in the prior art; the rosin clear oil mixture is prepared by heating and mixing 1kg of rosin resin and 1kg of novolac.
In the control example, the healing rate of 39 tomato seedlings with main stem growing points removed is 78%; the average callus formation time was 8d; the average time length in the seedling stage is 26d.
Comparative example 4
The processing method and the cultivation environment of the tomato multi-head seedlings in the comparative example are basically the same as those in the example 4, and the differences are only that: the bleeding healing agent used in this comparative example was a bordeaux protectant used in the prior art; the Bordeaux mixture protective agent is prepared by stirring 0.5kg of copper sulfate, 1.5kg of hydrated lime, 7.5kg of water and 0.2kg of lard.
In the comparative example, the healing rate of 41 tomato seedlings with main stem growing points removed and wounds is 82%; the average callus formation time was 7.5d; the average time length in the seedling stage is 25d.
As can be seen from the comparison between the above examples 1 to 4 and comparative examples 2 to 4 and comparative example 1, the removal of the growing points of the main stems and the treatment of the main leaves can shorten the seedling stage duration of the tomato seedlings, which can be shortened by more than one week in comparison with the untreated tomato seedlings; the reason for this phenomenon may be that the growing point of the main stem is removed and the ratio of the area of the leaves is controlled, the cultivation environment of the tomato seedling is precisely controlled, the auxin and cytokinin generated by the leaves are transferred to the leaf axils corresponding to the leaves, the germination of the tomato branches is promoted, the seedling germinates the growing point at the true leaf axils, and the time of the seedling in the seedling stage is shortened.
As can be seen from the comparison between examples 1 to 4 and comparative examples 2 to 3, the healing rate of the tomato seedlings is increased after the bleeding healing agent is used, which is beneficial to the cultivation and development of the tomato seedlings and the prevention of the invasion of diseases and the nutrition loss in the bleeding period. In addition, the wound healing agent provided by the present invention has a better healing promoting effect than the healing agents used in the prior art in comparative examples 2 to 3, and the duration in the seedling stage is also lower than that in comparative examples 2 to 4. The reason for this may be that the molecular chain of the wound healing agent has good ductility, macroscopically shows good fluidity, and can be spread on the surface to form a protective film when being applied to the wound; with the drying of the moisture, the wound healing agent is gradually solidified and attached to the wound, so that the wound and the external environment are effectively isolated, and the invasion of diseases is prevented. Along with the healing of the tomato sprout wound, the amido bond or urea bond at the molecular chain end of the wound healing agent is degraded to release phenylalanine and histidine; phenylalanine can promote the synthesis of phenylalkane compounds such as lignin; histidine can provide a precursor of carbon skeleton hormone and is a catalytic enzyme for synthesizing cytokinin, the cytokinin is closely related to the formation of vascular tissues, and can induce the generated callus, under the influence of two amino acids, the wound healing is accelerated, the loss of nutrient components is less, the tomato germchit survival is facilitated, and the seedling period is also shortened.
Test example 1
The degradation performance test of the wound healing agent prepared by the invention is carried out by referring to a specific method in the national standard GB/T19277.2-2013 'determination of the final aerobic biological decomposition capability of materials under the controlled composting condition'. The compost container was placed in a thermostatted incubator at 58 ℃. The mixture in the compost container should be stirred in the other container at least once a week. Make up for the corresponding mass loss of water and mix well, then reload the mixture into the compost container to continue the biodegradation test. Air saturated with water and free of carbon dioxide is obtained by passing the air through a wash bottle containing soda lime and water, and the flow rate of the gas is controlled by a flow meter to make the air enter a compost container. Ammonia, water and volatile organic acid in the exhaust gas of the compost container are respectively removed by sulfuric acid with the concentration of 1mol/L, silica gel and anhydrous calcium chloride. The carbon dioxide in the gas is absorbed by an absorption device containing soda lime, soda talc and anhydrous calcium chloride in the form of sodium carbonate and water (the carbon dioxide gas reacts with sodium hydroxide). The amount of carbon dioxide released was measured by weighing the absorption apparatus charged with soda lime and soda talc to periodically measure and calculate the biological decomposition rate of the test material under the decomposed composting conditions. The composting period was 45d, the amount of carbon dioxide released was periodically weighed with an electronic balance, the percentage of biodegradation of the material was obtained by comparing the amount of carbon dioxide released with the theoretical amount of carbon dioxide released, and the test was ended when the biodegradation reached a plateau. According to the followingThe formula calculates the biological decomposition percentage D of the test material in each test container according to the accumulated carbon dioxide t (%):
In the formula:
for each test vessel V from the start of the test to time t
T The amount of carbon dioxide released is accumulated and the unit is gram (g);
for each empty container V from the start of the test to time t
B The average value of the accumulated carbon dioxide release is expressed in gram (g);
m(ThCO 2 ) The theoretical amount of carbon dioxide released is in grams (g) for each container of test material.
The results of the biological decomposition performance test of the bleeding wound healing agent are shown in Table 1.
TABLE 1
As can be seen from the results in Table 1, the wound healing agents 45d each showed a decomposition rate of more than 70% and showed a good biological decomposition rate. The reason for this may be that the wound healing agent has a low degree of cross-linking, and amide bonds or urea bonds in the molecular chain are biodegradable and can be decomposed into small molecular substances over time for degradation.