CN110999711A

CN110999711A - Blueberry weak tree rejuvenation method

Info

Publication number: CN110999711A
Application number: CN201911377694.XA
Authority: CN
Inventors: 赵健; 刘婧; 于春燕
Original assignee: Qingdao West Coast Agricultural High Tech Service Co Ltd
Current assignee: Qingdao West Coast Agricultural High Tech Service Co Ltd
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-04-14

Abstract

The invention discloses a method for rejuvenating weak blueberry trees, which belongs to the technical field of agricultural yield increase, and adopts mixed liquid medicine consisting of hymexazol, methyl frost and manganese zinc to prevent and control harmful microorganisms in soil, can thoroughly sterilize the soil, adopts parent soil I to improve the physical state of the soil and increase beneficial microorganisms in the soil, is matched with sawdust to increase the air permeability of the soil, can promote the weak seedling to take root by matching, further achieves the aim of rejuvenating the weak seedling, avoids the condition that the big trees and the replanted seedlings are planted in the same land block and are inconvenient to manage subsequently, can furthest reserve the existing yield, can adopt the measure to remedy when the seedlings just begin to yellow and the growth begins to weaken, effectively reduces the death rate of the seedlings, does not need to perform replante after the seedlings die or lose culture value, greater economic losses are avoided.

Description

Blueberry weak tree rejuvenation method

Technical Field

The invention relates to the technical field of agricultural yield increase, in particular to a blueberry weak tree rejuvenation method.

Background

Blueberries (blueberries) are an emerging small berry type fruit tree that first developed in the united states in the beginning of the 20 th century. The blueberry health food is rich in anthocyanin, arbutin, flavone and other antioxidant substances, has various health care functions of improving eyesight, enhancing memory, softening blood vessels, resisting cancer and the like, is combined with the food and agriculture organization of China to classify blueberries as one of five kinds of human health food, and has wide development prospect at home and abroad.

In the early construction of blueberry parks, due to insufficient experience, no attention is paid to soil improvement or soil improvement is not in place. Most growers only dig planting pits on the ridge surface after ridging, and each planting pit only uses about 0.01-0.02 square of turfy soil for soil improvement. The operation has the advantages that organic matters for soil improvement are less, the organic matters are only concentrated around the planting pits, the condition of uneven stirring of turfy soil often occurs, seedlings in the garden built in the early period often cannot enter the high-yield period for many years, or the seedlings entering the high-yield period are influenced by factors such as incomplete soil improvement, small improvement range and the like, and the conditions of seedling root rot, yellow leaf and even death are easily caused in the original soil areas with heavy viscosity and low-lying areas or years with much rainfall.

The current treatment for the above situation is mostly to remove weak seedlings that have died or have no cultivated value and replant with new seedlings. According to the proportion of dead seedlings and weak seedlings in the total nursery stock in the plot, the method can be divided into local replanting and whole replanting. The local replanting is mainly used for the condition of sporadic dead seedlings in the plot, and because other seedlings exist in the plot, the soil can not be improved again by large machinery, and only the soil can be improved in the original fixed planting holes by manpower, and new seedlings are planted again; the whole block of replanting is mostly used for the condition that dead seedlings and weak seedlings exist in the whole land, all the seedlings can be removed, and the rotary tillage, soil improvement, ridging and planting are carried out again (the strong seedlings which are removed individually can be planted back to the land).

Local replanting can not use large-scale machinery to improve soil again because there are other nursery stocks in the plot, can only use the manual work to change soil in the original planting cave, plant the new seedling again, its shortcoming as follows: 1) the labor cost is high, the time and the labor are wasted, and the method is not suitable for large-area popularization and application; 2) the soil is locally improved, the newly added soil improvement material is not easy to be uniformly mixed with the original soil, the soil environment around roots is not favorably and thoroughly improved by seedlings in the whole garden, the seedlings which are not problematic temporarily can be yellowed or die successively under the conditions of soil water stress and the like caused by various reasons; 3) the big trees and the replanted seedlings are planted in the same land, which is not beneficial to the subsequent management of the seedlings, and the phenomenon that the replanted seedlings die due to longer watering interval often occurs.

The whole block of replanting is to remove all the original seedlings and to perform one planting operation on the land again. Some nursery stocks with still good growth on the land can be dug out for replanting, which can seriously damage the tree vigor, and the operation cost is high, the short-term income is greatly reduced, and the growth is greatly prolonged in the high-yield period.

Meanwhile, the method belongs to a remedial measure, is operated under the condition that the seedlings die or lose the cultivation value, and does not relate to the conditions that the seedlings just begin to yellow and the growth vigor just begins to weaken. At present, for weak seedlings with cultivation value, related researches in China on rejuvenation methods are few.

Disclosure of Invention

The invention provides a blueberry weak tree rejuvenation method aiming at the phenomenon that seedlings cannot grow into high-yield trees for many years or leaves of big trees yellow and even die in the years with much rainwater due to incomplete and short-standing soil improvement in the development of earlier blueberry planting gardens, and the blueberry weak tree rejuvenation is realized by combining measures of soil sterilization, soil aggregate structure increase, beneficial soil microorganism promotion, soil air permeability improvement and the like, so that the high quality and high yield of blueberries are ensured.

The specific technical scheme provided by the invention is as follows:

the method for rejuvenating the weak blueberry trees, provided by the invention, comprises the following steps:

performing first root irrigation treatment on the blueberry weak trees in 3-4 months in the current year by using a mixed liquid medicine consisting of hymexazol and metalaxyl, wherein the mixed liquid medicine completely infiltrates the whole root system range of the blueberry weak trees, the effective component of the hymexazol is not less than 99%, the effective component of mancozeb in the metalaxyl is not less than 48%, and the effective component of the metalaxyl in the metalaxyl is not less than 10%;

after root irrigation is finished for one month, continuously carrying out secondary and third root irrigation treatments by adopting a soil-philic series I liquid soil conditioner, wherein the liquid soil conditioner completely infiltrates the whole root system range of the blueberry weak tree in the secondary root irrigation treatment and the third root irrigation treatment, and the time interval between the secondary root irrigation treatment and the third root irrigation treatment is 8-12 days;

and in the 10 th month of the year, after the new shoots of the weak blueberry trees stop growing, the sawdust is used for hole expanding treatment, and the sawdust and the original soil are uniformly stirred without damaging the whole root systems of the weak blueberry trees.

Optionally, the mixed liquid medicine consisting of hymexazol and methyl frost, manganese and zinc is used for performing first root irrigation treatment on the blueberry weak trees in 3-4 months in the current year, and the method specifically comprises the following steps:

stirring and mixing hymexazol with the dilution multiple of 3000 times and methyl cream with the dilution multiple of 1500 times, manganese and zinc to prepare a mixed liquid medicine, wherein water is used as a diluent for both the hymexazol and the methyl cream;

and (3) performing first root irrigation treatment on the blueberry weak trees by using a mixed liquid medicine consisting of hymexazol, metalaxyl and manganese zinc in 3-4 months in the current year, wherein the effective component ratio of the hymexazol, the mancozeb and the metalaxyl in the mixed liquid medicine is 99:48: 10.

Optionally, after the root irrigation is finished for one month, continuously performing secondary and third root irrigation treatments by using a soil-philic series of liquid soil conditioners, specifically:

diluting a soil-philic series liquid soil conditioner according to the dilution concentration of at least 300 times to form a soil-philic series liquid soil conditioning diluent, wherein water is adopted as the diluent in the process of diluting the soil-philic series liquid soil conditioner;

after the first root irrigation treatment is finished for one month, according to the usage amount of at least 5 liters of the soil-philic first liquid soil conditioner per mu, performing second root irrigation treatment on the blueberry weak trees by using the soil-philic first liquid soil conditioning diluent, and ensuring that the whole root system range of the blueberry weak trees is completely infiltrated by the soil-philic first liquid soil conditioning diluent in the second root irrigation treatment;

and after the second root irrigation treatment is finished for 10 days, according to the usage amount of at least 5 liters of the first soil-philic liquid soil conditioner used per mu, performing third root irrigation treatment on the blueberry weak trees by using the first soil-philic liquid soil conditioning diluent, and ensuring that the whole root system range of the blueberry weak trees is completely infiltrated by the first soil-philic liquid soil conditioning diluent in the third root irrigation treatment.

Optionally, the active ingredients of the soil-philic series I liquid soil conditioner comprise humic acid, nitrogen phosphorus potassium and Saf bioenergy soil loosening factors.

Optionally, after the young shoots of the weak blueberry trees stop growing in the month 10 of the year, sawdust is used for hole expanding treatment, and the sawdust and original soil are uniformly stirred without damaging the whole root systems of the weak blueberry trees, and the method specifically comprises the following steps:

after the new shoots of the weak blueberry trees stop growing in the month 10, ditching along the planting rows, wherein the ditching position is determined according to the tree age and the plant size of the weak blueberry trees, the ditching depth is 30-40 cm, and the ditching width is 15-20 cm;

uniformly scattering sawdust on the bottom and two sides of the ditch according to the dosage of 0.02-0.03 square of sawdust of a single blueberry weak tree;

uniformly stirring and mixing the ditching original soil and the sawdust according to the volume fraction ratio of 3:1 to form mixed soil, backfilling the mixed soil, and watering to ensure that the soil in the whole root system range of the blueberry weak trees is wetted.

Optionally, after the young shoots of the weak blueberry trees stop growing in the month 10 of the year, ditching is carried out along the planting line, specifically:

and after the new shoots of the weak blueberry trees stop growing in 10 months in the same year, ditching along the fixed planting rows, wherein ditching positions are determined according to the tree ages, the plant sizes and the root system conditions of the weak blueberry trees, and the principle that the root can not be cut off in a large amount in ditching and the root systems of the weak blueberry trees are exposed on the inner sides of ditches is taken as a principle.

Optionally, the distance between the ditching position and the blueberry weak tree plant is in a direct proportion relation with the tree age, the plant size and the root system condition of the blueberry weak tree.

The invention has the following beneficial effects:

the embodiment of the invention provides a method for rejuvenating weak blueberry trees, which adopts mixed liquid medicine consisting of hymexazol, methyl frost, manganese and zinc to prevent and control harmful microorganisms in soil, can thoroughly sterilize the soil, adopts the first parent soil to improve the granular structure of the soil and increase beneficial microorganisms in the soil, is matched with sawdust to increase the air permeability of the soil, can promote the weak seedlings to root by matching with each other, further achieves the aim of rejuvenating the weak seedlings, avoids the situation that the large trees and the replanted small seedlings are planted in the same plot and are inconvenient to manage subsequently, can furthest retain the existing yield, can adopt the measure to remedy when the seedlings just start to yellow and the growth begins to weaken, effectively reduces the death rate of the seedlings, does not need to replante after the seedlings die or lose culture value, greater economic losses are avoided.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of a root system structure after rejuvenation treatment by the blueberry weak tree rejuvenation method according to the embodiment of the invention;

fig. 2 is a schematic diagram of the root structure of the same blueberry weak tree after rejuvenation treatment by adopting the prior art.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The method for rejuvenating weak blueberry trees according to the embodiment of the invention is described in detail with reference to fig. 1-2, and not only can kill germs directly causing blueberry root rot, but also can effectively solve the problem of poor rhizosphere environment caused by incomplete soil improvement during blueberry planting through a plurality of measures.

Referring to fig. 1 and fig. 2, a method for rejuvenating a weak blueberry tree provided by the embodiment of the invention comprises the following steps:

the method comprises the following steps: the method comprises the steps of performing first root irrigation treatment on weak blueberry trees in 3-4 months in the current year by using a mixed liquid medicine consisting of hymexazol and metalaxyl, wherein the mixed liquid medicine completely infiltrates the whole root system range of the weak blueberry trees, the effective component of the hymexazol is not less than 99%, the effective component of mancozeb in the metalaxyl is not less than 48%, and the effective component of the metalaxyl in the metalaxyl and the manganin is not less than 10%.

Specifically, in 3-4 months of the year, firstly, stirring and mixing hymexazol with the dilution multiple of 3000 times and first cream with the dilution multiple of 1500 times, manganese and zinc to prepare a mixed liquid medicine, wherein water is used as a diluent for both the hymexazol and the first cream; and then, performing first root irrigation treatment on the blueberry weak trees by using a mixed liquid medicine consisting of hymexazol, metalaxyl and manganese zinc, wherein the effective component ratio of the hymexazol, the mancozeb and the metalaxyl in the mixed liquid medicine is 99:48: 10.

For example, weak seedlings which are obviously shown in the last year but are not rejuvenated in time can be observed and detected, and the weak seedlings of blueberries which are caused by the weak seedlings and have the causes of uneven mixing of soil improvement materials during planting, poor air permeability of soil near root systems, detectable pathogenic microorganisms and rotten root systems can be confirmed, hymexazol (active ingredient 99%) + methyl cream and manganese zinc (active ingredients mancozeb 48% and metalaxyl 10%) can be used for root irrigation for 1 time in last ten days of the current 4 months, the mixed liquid medicine is required to be ensured to completely infiltrate the whole root system range of the blueberry weak trees in the root irrigation process, the dilution multiple of the hymexazol is 3000 times, the dilution multiple of the methyl cream and the dilution multiple of the manganese zinc are 1500 times, and the active ingredients of the mixed liquid medicine comprise the hymexazol, the mancozeb and the metalaxyl.

The hymexazol is systemic efficient pesticide bactericide and soil disinfectant and is also a plant growth regulator. The hymexazol has unique drug effect, high efficiency, low toxicity and no public nuisance, belongs to a green environment-friendly high-tech medicine, can effectively inhibit the normal growth of pathogenic fungi mycelium or directly kill germs, and can promote the growth of plants; the hymexazol also has the effects of promoting the growth and development of crop roots, rooting and strengthening seedlings and improving the survival rate of crops.

The mancozeb in the mixed liquid medicine adopted in the method of the embodiment of the invention is an excellent protective bactericide, and belongs to low-toxicity pesticides. The mancozeb has wide sterilization range and is not easy to generate resistance. Meanwhile, the trace elements of manganese and zinc in mancozeb have obvious effects of promoting the growth of weak blueberry trees and increasing yield. The metalaxyl in the mixed liquid medicine adopted in the method of the embodiment of the invention is a systemic specific bactericide, has the functions of protecting the root system and treating, can be absorbed by the root, stem and leaf of the plant, and is transferred to each organ of the plant along with the transportation of water. In addition, a large number of practices show that the hymexazol, mancozeb and metalaxyl adopted in the embodiment of the invention are matched with each other to use, so that the soil sterilization effect is better.

Step two: and after the root irrigation is finished for one month, continuously carrying out secondary and third root irrigation treatments by adopting a soil-philic series I liquid soil conditioner, wherein the liquid soil conditioner completely infiltrates the whole root system range of the blueberry weak tree in the secondary root irrigation treatment and the third root irrigation treatment, and the time interval between the secondary root irrigation treatment and the third root irrigation treatment is 8-12 days.

Specifically, diluting a soil-philic series liquid soil conditioner according to at least 300 times of dilution concentration to form a soil-philic series liquid soil conditioning diluent, wherein water is adopted as the diluent in the diluting process of the soil-philic series liquid soil conditioner; after the first root irrigation treatment is finished for one month, according to the usage amount of at least 5 liters of the soil-philic first liquid soil conditioner per mu, performing second root irrigation treatment on the blueberry weak trees by using the soil-philic first liquid soil conditioning diluent, and ensuring that the whole root system range of the blueberry weak trees is completely infiltrated by the soil-philic first liquid soil conditioning diluent in the second root irrigation treatment; and after the second root irrigation treatment is finished for 10 days, according to the usage amount of at least 5 liters of the first soil-philic liquid soil conditioner used per mu, performing third root irrigation treatment on the blueberry weak trees by using the first soil-philic liquid soil conditioning diluent, and ensuring that the whole root system range of the blueberry weak trees is completely infiltrated by the first soil-philic liquid soil conditioning diluent in the third root irrigation treatment.

The active ingredients of the soil-philic series of liquid soil conditioners adopted by the embodiment of the invention comprise humic acid, nitrogen phosphorus potassium and Saf bioenergy soil loosening factors. The first soil-philic series liquid soil conditioner can be of a golden brand, contains nutrients such as humic acid, nitrogen, phosphorus and potassium and bioenergy soil loosening factors, and can prevent and break soil hardening, loosen soil and improve the physical state of the soil; the Saf bioenergy soil loosening factor can activate soil microorganisms, and improve the disease resistance and yield of crops.

Step three: and in the month 10, after the new tips of the weak blueberry trees stop growing, saw dust is used for hole expanding treatment, and the saw dust and original soil are uniformly stirred without damaging the whole root systems of the weak blueberry trees, wherein the ditching position is preferably at the inner side of the fertilizing ditch so as to just expose the root systems.

Specifically, after the new shoots of the weak blueberry trees stop growing in the month 10 of the year, ditching is carried out along the planting rows, wherein the ditching position is determined according to the tree age and the plant size of the weak blueberry trees, the ditching depth is 30-40 cm, and the ditching width is 15-20 cm; uniformly scattering sawdust on the bottom and two sides of the ditch according to the dosage of 0.02-0.03 square of sawdust of a single blueberry weak tree; uniformly stirring and mixing the ditching original soil and the sawdust according to the volume fraction ratio of 3:1 to form mixed soil, backfilling the mixed soil, and watering to ensure that the soil in the whole root system range of the blueberry weak trees is wetted. The blueberry root system needs to be loose and breathable, and the ventilation of the soil can be effectively increased after the sawdust and the raw soil are mixed, so that the blueberry weak tree root system can naturally and rapidly grow after a suitable growing environment is provided for the blueberry weak tree root system. In addition, the saw dust is matched with a soil-philic series of liquid soil conditioners remained in the soil, so that the rapid growth of the root system of the weak blueberry tree can be better promoted.

Specifically, after the new shoots of the weak blueberry trees stop growing in 10 months in the year, ditching is carried out along the field planting line, wherein the ditching position is determined according to the tree age, the plant size and the root system condition of the weak blueberry trees, and the principle that the root is not cut off greatly in ditching and the root system of the weak blueberry tree is exposed on the inner side of the ditch is taken as the principle. The distance of ditching position apart from the weak tree plant of blueberry all is direct proportion with the age of the weak tree of blueberry, plant size, root system condition, and the age of the weak tree of blueberry is big more, the plant size is big more, the root cap scope is wide more also, and the distance of the position of ditching that sets up apart from the weak tree plant of blueberry is far away more. In the blueberry weak tree rejuvenation method provided by the embodiment of the invention, when ditching is carried out along the fixed planting rows, the distance between a ditching position and a blueberry weak tree plant cannot be too far or too close, and the effect of increasing the air permeability of soil near the root system of the blueberry weak tree by sawdust cannot be ensured when the ditching position is too far, so that the rejuvenation effect of the blueberry weak tree can be influenced; if the ditching position is too close, the existing root system of the weak blueberry tree can be damaged in the ditching process, and the rejuvenation of the weak blueberry tree in the later period is more favorably realized. Therefore, the method for rejuvenating the weak blueberry trees determines the ditching position according to the tree age, the plant size and the root system condition of the weak blueberry trees, and determines the ditching position on the basis that the ditching does not cause a large number of broken roots and the root system of the weak blueberry trees is exposed on the inner side of the ditch, so that the effects of the liquid soil conditioner of the series of sawdust and parent soil can be exerted to the maximum extent, and the blueberry trees are guaranteed to have ideal rejuvenating effect.

Illustratively, after the weak blueberry tree is stopped growing at a new tip in autumn, sawdust (pine sawdust is the best) is used for expanding cavities and ditching along the fixed planting line, the ditching position needs to be determined according to the seedling root crown range, the inner side of ditching is required to be just suitable for exposing roots, a small amount of roots can be cut, but a large amount of roots cannot be cut or the roots are too far away from the root system, the ditch depth is about 35 cm, the width is between 15 cm and 20cm, the amount of sawdust used by a single plant is about 0.02 cm, the sawdust is uniformly scattered at the ditch bottom and two sides of the ditch after ditching and is uniformly mixed with the original soil, and then the ditch is backfilled by using the mixed soil and is watered in time. As the blueberry root system needs to be loose and breathable, the air permeability of the soil can be effectively increased after the sawdust and the raw soil are mixed, and then after a proper growing environment is provided for the root system, the blueberry weak tree root system can naturally and rapidly grow, and the effect of rejuvenating the blueberry weak trees is rapidly achieved.

According to the method for rejuvenating the weak blueberry trees, provided by the embodiment of the invention, for the condition that particularly heavy soil or soil improvement materials are not uniformly mixed during field planting, the liquid soil conditioners of the parent soil I series are matched with the sawdust for use, so that the condition that the effect of singly using the liquid soil conditioners of the parent soil I series is not enough to provide a sufficiently loose and breathable environment for root systems can be avoided, meanwhile, the condition that singly using the sawdust cannot improve the rhizosphere environment in the range close to the root stems can be avoided, and the quick rejuvenating effect of the weak blueberry trees can be achieved by mutually matching the liquid soil conditioners of the parent soil I series and the sawdust.

It should be noted that, for blueberry plants (mostly in the young fruit development period and rainy season in the middle ten days of 5 months) which have no obvious expression in the early stage but have weak trees due to waterlogging and other factors, observation and detection confirm that the weak seedlings are caused by uneven mixing of soil improvement materials during planting, poor air permeability of soil around roots and weak plant growth caused by root rot, so that young fruits can be properly thinned according to the tree vigor, and after fruit picking, the blueberry weak tree rejuvenation method provided by the embodiment of the invention is adopted for rejuvenation, and the rejuvenation effect is found to be very obvious through practice.

The blueberry weak tree rejuvenation method provided by the embodiment of the invention is applied to a new Dianwang blueberry base on the west coast of Qingdao city in Shandong province in 2017 for experimental analysis. The blueberry variety of the base is 'Xilai', 3 years of seedlings are planted in autumn in 2013, the row spacing of the seedlings is 1 m multiplied by 2.2 m, and during planting, each seedling of the plot uses 0.017 square turfy soil to artificially improve the soil in a hole mode. The field nursery stocks bear a small number of fruits from 2014, the yield of the field nursery stocks exceeding 2.5 kg/plant in 2017 and the yield-free nursery stocks basically account for half of the total number of the nursery stocks, the yield-free nursery stocks are mostly concentrated in the region with lower terrain of the field, and the fruiting trees die after rainy seasons appear in recent years. The observation of the seedling planting environment and the detection of pathogenic bacteria can confirm that the reason for causing the seedling to be weak is that the soil is sticky, the soil improvement material is insufficient during planting, the ridging height is lower, the seedlings in the lower region of the terrain suffer from water stress frequently, the respiration of the roots is limited, similar conditions also occur after a large amount of rainfall in other regions, the roots are rotten, and finally the seedlings die.

In allusion to the situation, in 2017, on 10 days 4 months, 3000 times of hymexazol (with an effective component of 99%) + 1500 times of metalaxyl and manganese zinc (with an effective component of 48% of mancozeb and 10% of metalaxyl) are used for root irrigation, and 10 kg of drip irrigation liquid medicine is applied to each plant; irrigating roots of the plants with a first parent soil series of liquid soil conditioners once in 5 months, 12 days and 22 days in 5 months and the year, wherein the consumption of the first parent soil is 5 liters per mu each time, and each plant is subjected to drip irrigation and is provided with 10 kilograms of fertilizer solution; after the young sprout stops growing in the autumn of 10 and 5 days in the year, the pine tree sawdust is used for hole expanding, furrowing is conducted in the fixed planting row, the distance from the inner side edge of the fertilizing ditch to the nursery stock rhizome is 25-30 cm, the furrow depth is 35 cm, the furrow width is 20cm, the amount of the pine tree sawdust used by a single plant is 0.02 square, after furrowing, the pine tree sawdust is uniformly scattered at the bottom and the two sides of the ditch and is uniformly mixed with the original soil, backfilled and watered in time.

The new root length and the death rate of the plants rejuvenated by the blueberry weak tree rejuvenation method provided by the embodiment of the invention and the control plants (seedlings which do not adopt the rejuvenation method provided by the embodiment of the invention) are counted in 2018 and 10 months. The analysis statistics are shown in table one below:

table one: 2018 analysis and comparison of results

Treatment of	Mortality (%)	New root length (& lt & gtcm & gt)
			The rejuvenation method	2.2	14.5
Control	7.9	＜1

The root system of a plant rejuvenated by the weak blueberry tree rejuvenation method provided by the embodiment of the invention is shown in the attached drawing 1, while the root system of a control plant (a seedling not adopting the rejuvenation method provided by the embodiment of the invention) is shown in the attached drawing 2, and the comparison between the drawings 1 and 2 shows that a large amount of new roots are generated in the seedling root system of the plant rejuvenated by the weak blueberry tree rejuvenation method provided by the embodiment of the invention.

The blueberry weak tree rejuvenation method provided by the embodiment of the invention is applied to a new area of the west coast of Qingdao, Shandong province, Hanjialiu blueberry base in 2017. The blueberry variety is 'Berkeley', 3-year seedlings are planted in 2013 spring, the row spacing of the seedlings is 1 meter multiplied by 2.4 meters, and soil is artificially subjected to hole improvement by using 0.017 square turf soil for each plant during planting. The yield of each seedling reaches 3.5 kg from 2017, and the yield is continuously increased every year in the future, but meanwhile, the seedlings in the region die sporadically after rainy season, abnormal conditions of the seedlings are advanced in the last two years, the phenomena that the leaves of some seedlings are seriously yellow and die in autumn during the young fruit development period are generated, and the quantity of the seedlings with abnormal expression and the quantity of accumulated dead seedlings are increased year by year. The inspection by observing the root environment and pathogenic bacteria can confirm that the reason for causing the seedling to be weak is that the soil improvement material is not enough during planting, the mixing is not uniform, the air permeability of the soil around the root system is poor, and the root system of the seedling is rotten.

In allusion to the situation, in 2018, on 8 months and 10 days, 3000 times of hymexazol (with an effective component of 99%) + 1500 times of metalaxyl and manganese zinc (with an effective component of 48% of mancozeb and 10% of metalaxyl) are used for root irrigation, and each plant is subjected to drip irrigation and is applied with 12 kg of liquid medicine; irrigating roots with a first parent soil in 10 days after 9 months and 20 days after 9 months respectively, wherein the consumption of the first parent soil is 5 liters per mu each time, and each plant is irrigated with 12 kg of fertilizer solution by drip irrigation; after the young sprout stops growing in the autumn of 10 months and 8 days, the pine tree sawdust is used for hole expanding, furrowing is conducted in the fixed planting row, the distance from the inner side edge of the fertilizing ditch to the nursery stock rhizome is 30-35 cm, the furrow depth is 35 cm, the furrow width is 20cm, the amount of the pine tree sawdust used by a single plant is 0.02 square, after furrowing, the pine tree sawdust is uniformly scattered at the bottom of the ditch and on the two sides of the ditch and is uniformly mixed with the original soil, and then the ditch is backfilled by using the mixed soil and is watered in time.

The yellowing rate of the plants rejuvenated by the weak blueberry tree rejuvenation method provided by the embodiment of the invention and the control plants (seedlings which do not adopt the rejuvenation method provided by the embodiment of the invention) is counted in 5 months in 2019, and the length of new roots and the death rate are counted in 10 months in 2019. The analysis statistics are shown in the following table two:

table two: 2019 analysis and comparison results

Treatment of	Yellowing ratio (%)	Mortality (%)	New root length (& lt & gtcm & gt)
				The rejuvenation method	21	0.8	11.4
Control	46	6.2	2.3

According to the comparison results in the table two, compared with a control plant, the yellowing rate and the death rate of the plant rejuvenated by using the weak blueberry tree rejuvenation method provided by the embodiment of the invention are obviously reduced, and the seedling root system of the plant rejuvenated by using the weak blueberry tree rejuvenation method provided by the embodiment of the invention is generated with a large amount of new roots which are almost more than 5 times of those of the control plant.

The embodiment of the invention provides a method for rejuvenating weak blueberry trees, which adopts mixed liquid medicine consisting of hymexazol, methyl frost, manganese and zinc to control harmful microorganisms in soil, can thoroughly sterilize the soil, adopts the first parent soil to improve the granular structure of the soil and increase the beneficial microorganisms in the soil, is matched with sawdust to increase the air permeability of the soil, can promote the weak seedlings to root by matching with each other, further achieves the aim of rejuvenating the weak seedlings, avoids the situation that the subsequent management of planting big trees and small seedlings which are replanted in the same plot is inconvenient due to the fact that local replanted is possible, can furthest reserve the existing yield, can adopt the measure to remedy when the seedlings just start to yellow and the growth just starts to weaken, effectively reduces the death rate of the seedlings, does not need to replante the seedlings after the seedlings die or lose culture value, greater economic losses are avoided.

The method for rejuvenating the weak blueberry trees provided by the embodiment of the invention can take timely and effective measures when the seedlings are yellow and weak, effectively reduces the death rate of the seedlings, does not need to be replanted until the seedlings die or lose the culture value, and avoids greater economic loss. Moreover, the blueberry weak tree rejuvenation method provided by the embodiment of the invention is superior to local replanting in soil improvement degree of seedlings. The embodiment of the invention promotes weak seedling rooting by multiple angles of soil sterilization, granule structure promotion, beneficial microorganism increase, soil permeability increase and the like, so as to achieve the aim of weak seedling rejuvenation, the effect is not as obvious as that of the embodiment of the invention even if soil improvement materials are added again in local replanting, and the condition that large trees and replanting seedlings are planted in the same land and the subsequent management is inconvenient, which may be caused by local replanting, is avoided. Compared with the whole block re-planting, the method avoids moving the nursery stock with the cultivation value, can furthest keep the existing yield, and has the cost greatly lower than that of the whole block re-planting.

It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments of the present invention without departing from the spirit or scope of the embodiments of the invention. Thus, if such modifications and variations of the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to encompass such modifications and variations.

Claims

1. A blueberry weak tree rejuvenation method is characterized by comprising the following steps:

2. The method for rejuvenating weak blueberry trees as defined in claim 1, wherein the first root irrigation treatment is carried out on the weak blueberry trees by using a mixed liquid medicine consisting of hymexazol and methyl frost, manganese and zinc in 3-4 months of the year, and specifically comprises the following steps:

3. The method for rejuvenating weak blueberry trees as defined in claim 1, wherein the second and third root irrigation treatments are carried out successively with a soil-philic series of liquid soil conditioners one month after the root irrigation is completed, specifically:

4. The method for rejuvenating weak blueberry trees as recited in claim 3, wherein the active ingredients of the soil-loving series of liquid soil conditioners comprise humic acid, nitrogen phosphorus potassium, and Saf bioenergy scarification factors.

5. The method for rejuvenating weak blueberry trees as claimed in any one of claims 1 to 4, wherein the hole expanding treatment is performed by using sawdust after the young shoots of the weak blueberry trees stop growing in the month of 10 in the same year, and the sawdust and the original soil are uniformly stirred without damaging the whole root systems of the weak blueberry trees, and specifically comprises the following steps:

according to the volume fraction ratio of 3:1, uniformly stirring and mixing the ditching raw soil and the sawdust to form mixed soil, backfilling the mixed soil, and watering to ensure that the soil in the whole root system range of the blueberry weak tree is wetted.

6. The method for rejuvenating weak blueberry trees as claimed in claim 1 or 5, wherein after the young shoots of the weak blueberry trees stop growing in the month 10 of the year, furrowing is carried out along the planting rows, and specifically:

7. The method for rejuvenating a weak blueberry tree as claimed in claim 6, wherein the distance from the ditching position to the weak blueberry tree plant is in direct proportion to the tree age, the plant size and the root system condition of the weak blueberry tree.