AU2017388833B2

AU2017388833B2 - Method for controlling pests of tea

Info

Publication number: AU2017388833B2
Application number: AU2017388833A
Authority: AU
Inventors: Jieqi Fu; Kouji Ishigami; Hikaru Yoshida
Original assignee: Ito En Ltd
Current assignee: Ito En Ltd
Priority date: 2016-12-28
Filing date: 2017-12-27
Publication date: 2023-01-05
Anticipated expiration: 2037-12-27
Also published as: WO2018124175A1; JP6543006B2; CN109952022A; AU2017388833A1; CN109952022B; JPWO2018124175A1

Abstract

The present invention proposes a novel method which is for controlling pests of tea, which uses heated water, without using any pesticides, and with which it is possible to more effectively control pests of tea. The proposed method for controlling pests is characterized by applying a treatment in which a mist of heated water is brought into contact with tea leaves such that the surface temperature thereof becomes 45-55°C.

Description

Title of Invention: METHOD FOR CONTROLLING PESTS OF TEA

Technical Field

[0001]

The present invention relates to a method for

controlling pests of tea, which is for exterminating or

controlling pests in tea plant.

Background Art

[0002]

Various types of pests grow in fields such as a

tea field, and thus control of pests is essential to

cultivate a healthy tea plant. Tea manufacturers have

been tackled this problem by spraying an appropriate

amount of an appropriate agent at an appropriate time.

[0003]

As for such methods of control of tea by spraying an

agent, Patent Literature 1 (Japanese Patent Laid-Open

No. 7-31350), for example, discloses an apparatus for

spraying an agent on tea plant uniformly and

efficiently in a short time, in which many nozzles are

protruded from the lower surface of a substantially

arcuate substrate having a grip member and the agent is

supplied to the respective nozzles, in the operation of

extermination or control of pests attached to, e.g.,

branches of tea plant, such as scale insects.

[0004]

Furthermore, Patent Literature 2 (Japanese Patent

Laid-Open No. 7-289057) discloses a method for

controlling pest of tea plant using a device for

plucking tea leaves, which integrally has a plucking

mechanism that advances along a tea ridge to pluck tea

leaves and an application mechanism that applies an

agent to the tea plant, wherein the application mechanism applies the agent to cut ends of plucking of the tea plant immediately after the plucking mechanism plucks the tea leaves.

[00051

Meanwhile, the concern with methods of control

using an agent such as chemical fertilizer or pesticide

is their harmful effects on the health of human bodies

and environmental pollution. Thus, methods of

controlling pests using little or no chemical

fertilizer or pesticide have been proposed. Today

about 100 pesticide components are registered

particularly for tea in Japan, but those pesticide

components may not have been approved or standards for

pesticide residues are very low in many foreign

countries. Thus, for the export of tea, there is an

urgent need to consider a method of control without

using pesticide.

[00061

To this end, Patent Literature 3 (Japanese Patent

Laid-Open No. 2016-152794) discloses a method for

controlling pest with hot water by spraying hot water on

a farm field which has been specially maintained and

spraying a solution for organic farming on the surface of

leaves of crops when eggs, larvae or adults of pest are

attached thereon.

[0007]

Patent Literature 4 (Japanese Patent Laid-Open No.

2016-158522) discloses a method for controlling a

moisture-phobic pest, wherein a sensor for detecting the

degree of wetting is installed in a field at a position

close to an environment in which the moisture-phobic pest

lives and water is sprinkled on the field according to

the detection value of the sensor to create a situation

in which the moisture-phobic pest is repelled or is

difficult to live.

[0008]

Furthermore, Patent Literature 5 (Japanese Patent

Laid-Open No. 2011-212012) discloses, as a method of

control without using pesticide, a method for controlling

pests of a plant seedling, wherein saturated steam flow

adjusted to a predetermined temperature is generated in a

treatment space surrounding the plant seedling so that

the saturated steam flow flows horizontally above the

plant seedling and the plant seedling is exposed to the

saturated steam flow for a period of time in which it

does not suffer from heat damage.

[00091

Non-patent literature 1 discloses that if a plant

such as strawberries is placed in a high temperature

condition of 40 to 500C for several ten seconds to

several minutes, the plant acts in various ways and

acquires resistance to diseases, becoming less likely to

suffer from disease such as powdery mildew.

Citation List

Patent Literature

[0010]

Patent Literature 1: Japanese Patent Laid-Open No. 7

31350

Patent Literature 2: Japanese Patent Laid-Open No. 7

289057

Patent Literature 3: Japanese Patent Laid-Open No. 2016

152794

Patent Literature 4: Japanese Patent Laid-Open No. 2016

158522

Patent Literature 5: Japanese Patent Laid-Open No. 2011

212012

Non-patent Literature

[0011]

Non-patent Literature 1: Tatsuo Sato, "Control of Plant

Disease Using Heat Shock Treatment," Vegetable

Information, February, 2013.

Summary of Invention

Technical Problem

[0012]

Tea is a peculiar perennial plant and its

characteristic is that tea leaves are harvested several

times a year. The time of plucking varies depending on

the region. In Shizuoka Prefecture, for example,

usually the first crop tea is plucked in mid-April to

mid-May, then 45 to 50 days after the plucking of the

first crop tea, while waiting next shoots to grow, the

second crop tea is plucked, and then after waiting

about 3 months until autumn, the autumn and winter crop

tea is plucked.

Since control of such tea plant whose leaves are

harvested several times a year needs to be performed a

few times per time of plucking, pesticide which has

been sprayed in the period of earlier tea may remain and the type of pesticides and their concentration in tea leaves may be increased in the later period of plucking the third crop, the fourth crop or the autumn and winter crop tea. Furthermore, increased frequency of use of pesticide may require cost higher than that for usual crops. Thus, a novel and effective method of controlling pests without using pesticide has been needed.

[0013]

Accordingly, an object of the present invention is

to provide a novel method for controlling pests of tea

more effectively using heated water without using

pesticide.

Solution to Problem

[0014]

The present invention proposes a method for

controlling pests of tea, comprising carrying out a treatment to bring a mist of heated water into contact with tea leaves in such a manner that the temperature of the surface of the tea leaves is 450C to 55°C.

Advantageous Effects of Invention

[0015]

The method for controlling pests of tea proposed by

the present invention can control pests of tea

effectively by using heated water without using

pesticides.

Description of Embodiments

[0016]

The present invention will be hereinafter described

with reference to embodiments. However, the present

invention is not limited to the embodiments described

below.

[0017]

The method for controlling pests of tea according to

an embodiment of the present invention (referred to as

the present control method) comprises carrying out a

treatment to bring a mist of heated water (referred to as

"heated mist") into contact with tea leaves in such a

manner that the temperature of the surface of the tea

leaves is 450C to 55°C.

[0018]

(Subject tea)

The tea which is the subject of the present control

method may be tea which is grown for the purpose of

extracting tea leaves plucked or a processed product of

tea leaves into liquid and drinking the liquid. The tea

may be that grown for the purpose of eating tea leaves

plucked.

Specific examples include tea grown as middle-grade

tea, powdered tea, refined tea, oolong tea, black tea and

other teas for beverage.

[0019]

(Subject disease and pest)

Examples of diseases which are the subject of the

present control method include anthrax, gray blight,

brown blight, net blister blight and white rash.

Examples of pests causing damage include Empoasca onukii

(hereinafter referred to as a plant hopper), Tetranychus

kanzawai, Pseudaulacaspis pentagona, Scirtothrips

dorsalis, Adoxophyes honmai and Caloptilia theivora. The

disease and pest are not limited thereto.

[0020]

(Heated mist)

Water for the heated mist may be water such as tap

water or well water.

A chemical may be added if necessary.

[00211

It is preferable that the temperature of the heated

mist is adjusted to 450C to 550C. A heated mist of 45°C

or more is effective for controlling disease and pest. A

heated mist of 550C or less is capable of preventing

occurrence of heat damage.

From the above point of view, the temperature of the

mist of water to be in contact with tea leaves is

adjusted to preferably 450C to 550C, more preferably 470C

or more and 540C or less, and particularly preferably

500C or more and 530C or less.

[0022]

For the method of forming a mist of water, water

which has been heated may be formed into mist, or water

which has been formed into mist may be heated. Specific

examples thereof may include a method in which steam

prepared by using a boiler is cooled or a method in which fine droplets of water are sprayed into hot air. The method is not limited thereto.

[0023]

(Method of bringing heated water into contact with tea

leaves and tea plant)

It is preferable that the heated mist is brought

into contact with, out of at least tea plant and tea

leaves, tea leaves at the surface portion of the leaf

layer. It is also preferable that the heated mist is

brought into contact with tea leaves at the portion of

shoots to be plucked.

Bringing the mist into contact with tea leaves at

the surface portion of the leaf layer enables control of

conidia of disease and pests existing in the vicinity of

shoots and affecting their growth and quality.

Furthermore, bringing the mist into contact with tea

leaves at the portion of shoots to be plucked enables

direct control of shoots.

It is particularly preferable that the mist is also

brought into contact with the cut surface of stems and

young leaves with pubescence. Furthermore, usually it is

preferable that the mist is brought into contact with

leaves called "mother leaves," which have been hardened

and are located below the plucking surface. It is also

preferable that the mist is brought into contact with

branches and stems.

Bringing the heated mist into contact with the cut

surface of the stem enables effective control of gray

blight. Bringing the heated mist into contact with young

leaves with pubescence enables effective control of

anthrax. Furthermore, bringing the heated mist into

contact with mother leaves, branches and stems enables

control of conidia and pests attached to them.

[00241

It is preferable that the heated mist is brought

into contact with tea leaves and tea plant and the temperature of the surface of tea leaves is adjusted to

450C to 550C.

When the temperature of the surface of tea leaves is

450C or more, disease and pest are effectively

controlled. When the temperature of the surface of tea

leaves is 550C or less, occurrence of heat damage can be

prevented.

From the above point of view, the temperature of the

surface of tea leaves when the heated mist is brought

into contact with tea leaves and tea plant is adjusted to

preferably 450C to 550C, more preferably 460C or more and

530C or less, and particularly preferably 500C or more

and 520C or less.

Here, the temperature of the surface of tea leaves

may be adjusted by the temperature of the heated mist and

the time of contact.

[00251

It is preferable that the time of contact of the

heated mist with tea leaves (simply referred to as the

"contact time") is adjusted based on the temperature of

this water.

It is preferable that as a guide, the temperature of

water to be brought into contact with tea leaves and the

contact time of water to be brought into contact with tea

leaves are adjusted such that the product of the

temperature of the heated mist (A) and the contact time

(h), A x h, is 450C x 6 s to 550C x 15 s.

For example, carrying out a treatment to bring the

heated mist of 45°C into contacted with tea leaves for a

contact time of 6 seconds or less can prevent heat damage

while achieving an excellent effect of control.

Meanwhile, a contact time of 15 seconds or less is

equivalent to the contact time in conventional methods of

control.

From the above point of view, the product of the

temperature of the heated mist (A) and the contact time

(h), A x h, is adjusted to preferably 450C x 6 s to 550C

x 15 s, more preferably 460C x 6 s or more and 530C x 12

s or less, and particularly preferably 500C x 3 s or more

and 520C x 10 s or less.

[0026]

Furthermore, by adjusting temperature A (0C) of

water to be brought into contact with tea leaves and time

h (seconds) of bringing the heated mist into contact with

tea leaves such that {temperature A (0C) of heated mist

°C}^ 2 x {time h (seconds) of bringing heated mist into

contact with tea leaves} + 100 is 50 or less, more

preferably 10 or more and 40 or less, and particularly

preferably 12 or more and 30 or less, the effect of

control can be achieved in shorter time.

[0027]

(Timing of control treatment)

From the viewpoint of effective control of diseases

such as anthrax and gray blight, the above treatment,

i.e., the treatment to bring mist of heated water into

contact with tea leaves is carried out within preferably

2 weeks, more preferably a week, and particularly

preferably a day from the time when tea leaves are

plucked or trimmed.

[0028]

The above plucking of tea leaves is not particularly

limited as long as it is for harvesting tea leaves.

Plucking for harvesting the first crop tea or the second

crop tea is particularly preferred.

Furthermore, the above trimming of tea leaves means

work to prune the plucking surface after plucking tea

leaves. Trimming after plucking of the first crop tea or

the second crop tea is particularly preferred.

[0029]

It is particularly preferable that control is

carried out after the plucking of the first crop tea and

before the plucking of the second crop tea. However,

control may also be performed before the plucking of the

first crop tea or after the plucking of the second crop

tea.

Control is performed preferably within 14 days from

the day of the plucking of the first crop tea, more

preferably within 7 days from the day of the plucking,

and further preferably within 3 days from the day of the

plucking.

Since plucking hurts tea plant, conidia of gray

blight, for example, may be incorporated thereinto

through the cut. Thus, it is preferable to carry out

control immediately after plucking tea. This can also

reduce conidia of anthrax and can reduce plant hoppers

before sprouting.

[00301

Furthermore, from the viewpoint of preventing

occurrence of anthrax and plant hoppers, control is

carried out preferably within 10 to 25 days, and

particularly preferably within 15 to 20 days from the day

of plucking of the first crop tea, when the second crop

tea sprouts and the control is most effective.

[0031]

Meanwhile, from the viewpoint of preventing, e.g.,

gray blight, since portions cut by the blade of a

plucker, which is a likely source of infection of gray

blight, are infected, the above treatment, i.e., the

treatment to bring a mist of heated water into contact

with tea leaves is carried out within preferably 24

hours, more preferably 18 hours, and particularly

preferably 12 hours from the time when tea leaves are

plucked or trimmed.

[0032]

Tea plant may be grown using the present control

method and tea leave may be plucked at intervals in 2 to

4 stages out of the stages of the first crop tea (March

to May), the second crop tea (June to July), the third

crop tea (July to August), and the autumn and winter crop

tea (autumn).

In Kagoshima prefecture, for example, usually the

first crop tea is plucked in mid-April to mid-May, then

to 50 days after the plucking of the first crop tea,

waiting next shoots to grow, the second crop tea is

plucked, and then 40 to 45 days after the plucking of the

second crop tea, the third crop tea is plucked, and 50 to

days after the plucking of the third crop tea, the

fourth crop tea is plucked.

[00331

In crude tea factories, tea leaves plucked are

steamed in steam to inactivate oxidase in raw tea leaves

(parching) and then subjected to a series of processes including rough rolling, rolling, middle rolling, fine rolling and drying to be processed into crude tea, and then may be further processed according to the purpose of use.

[0034]

As used herein, the expression "X to Y" (X, Y

representing an arbitrary number) means not only "X or

more and Y or less," but also "preferably more than X"

and "preferably less than Y" unless otherwise specified.

Furthermore, the expressions "X or more" (X

representing an arbitrary number) and "Y or less" (Y

representing an arbitrary number) include the meaning

"preferably more than X" and "preferably less than Y"

Examples

[0035]

Hereinafter the present invention will be described

in more detail with reference to the following Examples

and Comparative Examples.

[00361

A mist of water (heated mist) of different

temperatures was sprayed on tea plant at the stage of

sprouting of the first crop tea, which is the most

vulnerable to the external environment, and conditions in

which no heat damage occurred were investigated.

[0037]

In a field in Shizuoka Prefecture, a heated mist of

to 650C was prepared and sprayed on tea plant and tea

leaves of a tea variety "Yabukita" using a commercially

available nozzle (20 heads) used for controlling tea for

3 seconds to 10 seconds. The temperature of the surface

of tea leaves (leaf temperature) was measured and the

occurrence of heat damage was observed.

[0038]

In this case, the mist of water of 40 to 650C was

prepared by mixing vapor produced by using a commercially

available boiler, SB-110 (made by Marubun Seisakusyo Co.,

Ltd.), and air in a mixer, measuring the temperature of

the mixed gas of vapor and air discharged from the

nozzle, and adjusting the amount of air incorporated into

the mixer based on the temperature measured to obtain a

mist of water, i.e., a heated mist, having the intended

temperature.

For the leaf temperature of tea leaves, the

temperature of the surface of mother leaves at the

surface portion of the leaf layer was measured using an

infrared thermometer (SK-8700II made by Sato Keiryoki

Mfg., Co., Ltd.)

For the determination of the occurrence of heat

damage, the heat damage was determined to be "occurred"

when the leaves were found to fall before they grew, for example, falling as if they were melted or falling while turning dark red; the heat damage was determined to be

"occurred in some portions" when some leaves were found

to be in such a condition, and determined to be "none"

when there were no such conditions.

[00391

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[0040]

While no heat damage occurred when a heated mist of

to 500C was applied even for a long period of time (10

seconds), heat damage occurred in some portions when a

heated mist of 55°C was applied for 10 seconds. When the

temperature of the heated mist was more than 600C, heat

damage occurred in a shorter period of time.

The treatment time of control should be less than 6

seconds from the viewpoint of work efficiency. Since

heat damage occurs when a heated mist of 600C is brought

into contact for 3 seconds, the substantial limit of the

treatment time is considered to be 6 seconds for a heated

mist of 55°C.

[0041]

The appropriate timing for performing the control

treatment to bring a mist of heated water (heated mist)

into contact with tea leaves was investigated.

[0042]

A control treatment was performed in a field in

Shizuoka Prefecture, in which a heated mist of 500C

prepared in the same manner as in Test 1 was sprayed on

tea plant and tea leaves of a tea variety "Yabukita" for

6 seconds in the same manner as in Test 1 to adjust the

leaf temperature to 50°C, within 24 hours (May 7) after

trimming for the purpose of leveling the plucking surface

after plucking of the first crop tea (April 23), in the

one-leaf stage (May 21) and the three-leaf stage (June

13), respectively.

Then, on the day of plucking of the second crop tea

(June 26), the occurrence of "anthrax," which is likely

to develop in the second crop tea of yabukita, and the

occurrence of "gray blight" and "insect pest," which are highly sensitive to yabukita, were observed. Cases in which no disease occurred were determined as "O (none)

" and cases in which the disease occurred were determined

as "X (occurred) , " respectively.

[00431

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[0044]

Effects of control equivalent to those in

conventional control were achieved in test regions 12 to

18, and thus it has been found that control using steam

is effective at any stage.

By contrast, in test region 19 in which no treatment

was performed, damage due to plant hoppers was

significant with 90% of shoots with four to five leaves

and a bud, i.e., the second crop tea, damaged. The

occurrence of anthrax and gray blight was therefore not

directly observed, while the occurrence of anthrax and

gray blight was observed at the end of a ridge in a

neighboring field in which conventional control was

insufficient. Considering that anthrax is spread by

diffusion of conidia through rain drops and gray blight

is spread by diffusion of conidia due to rain and

attachment of conidia to a plucker, the treatment of control of bringing a heated mist into contact with tea leaves has been found to be effective.

[0045]

Next, steps to the onset of disease and stages in

which control using steam is most effective will be

considered.

Anthrax is a disease infected through pubescence on

young shoots. The disease develops after an incubation

period of 14 to 20 days (8 to 15 days at the shortest)

after attachment to pubescence.

It has been found that methods for controlling such

anthrax is most effective at the stage in which shoots

with pubescence open (within 2 weeks after plucking or

trimming of the first crop tea).

Meanwhile, gray blight is a disease infected mainly

through the surface cut in plucking. Its conidia

germinate 2 to 3 hours after attachment and the disease

develops after an incubation period of 5 to 10 days. It has been said that in conventional control, control

(spraying of agent) needs to be performed within a day

after plucking, and the longer the interval, the less

effective the control.

The control of gray blight may be most effectively

performed within a day after plucking or trimming.

Since plant hoppers sucks the sap of only young

shoots, it is most effective to perform control at the

stage in which shoots open (within 2 weeks after plucking

of the first crop tea).

[0046]

The treatment of control of bringing a heated mist

into contact with tea leaves and tea plant has been found

to be effective even at stages other than the above

stages (e.g., test regions 13, 14). This can be

explained as follows.

Spraying of pesticide is roughly classified into

spraying of a "preventive agent" and spraying of a

"therapeutic agent." The above treatments performed

within a day after plucking or within 2 weeks after the

plucking of the first crop tea are all intended for

prevention. This is based on the idea that preventing

development of disease leads to production of tea leaves

with good quality. However, disease may develop even

after performing control and thus therapeutic agents are

used in conventional control. The time of use of

pesticide is clearly defined, and usually a preventive

agent should only be used until 30 days before plucking

of the second crop tea and a therapeutic agent should

only be used until 14 days before plucking of the second

crop tea. Therefore, pesticide cannot be sprayed in a

prescribed period before plucking, and thus disease has

been spread. However, since no pesticide is used in the

treatment of control of bringing a heated mist into

contact with tea leaves and tea plant, the treatment can

be carried out at a required time.

[0047]

The relation between the leaf temperature when a

mist of heated water (heated mist) was brought into

contact with tea leaves and the effect of control was

examined.

[0048]

A control treatment was performed in a field in

Shizuoka Prefecture, in which a heated mist of a

temperature shown in Table 3 prepared in the same manner

as in Test 1 was sprayed on tea plant and tea leaves of a

tea variety "Yabukita" in the same manner as in Test 1

for the treatment time shown in Table 3 to adjust the

leaf temperature to the temperature shown in Table 3,

within 24 hours after plucking of the third crop tea

(August 1).

Then, on the day of plucking of the fourth crop tea

(October 2), the occurrence of "anthrax," "gray blight" and "insect pest" was observed. Cases in which no disease occurred were determined as "0 (good)" and cases in which the disease occurred were determined as "X

(bad)," respectively.

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[0050]

Examples described above and the results of the

tests which have been carried out according to the

present invention show that pests of tea can be

controlled by bringing a heated mist into contact with

tea plant and tea leaves in such a manner that the

temperature of the surface of the tea leaves is 45°C or

more.

Furthermore, the occurrence of heat damage in test

region 32 shows that when the temperature of steam is 50

to 55°C and {temperature A (0C) of heated mist - 30°C}^ 2

x {time h (seconds) of bringing heated mist into contact

with tea leaves} + 100 is 50 or less, the effect of

control can be achieved in a shorter treating time and

heat damage does not occur.

[0051]

The relation among the leaf temperature when a mist

of heated water (heated mist) was brought into contact

with tea leaves, the frequency of treatment, and the

effect of controlling pest was examined.

[0052]

A treatment was performed in a field in Shizuoka

Prefecture, in which a heated mist of a temperature shown

in Table 5 prepared in the same manner as in Test 1 was

sprayed on tea plant and tea leaves of a tea variety

"Yabukita" in the same manner as in Test 1 for the

treatment time shown in Table 4 to adjust the leaf

temperature to the temperature shown in Table 4, every 10

days after plucking of the second crop tea for a total of

11 times (June 13 to October 13).

An insect pest trap (Bug-Scan manufactured by

Biobest, 10 cm x 13 cm) was installed at three places in

the respective test regions on August 22 during the

treatment period and collected on October 13. Then the number of pests attached to the trap was counted, and the effect of controlling pests in tea plant and tea leaves was investigated. The results are shown in Table 4.

For pests, a typical pest of tea leaves and tea

plant, Empoasca onukii, was selected. The effect of

controlling the pest was evaluated based on the average

species population of Empoasca onukii attached to the

insect pest trap installed at three places in the

respective test regions.

[00531

[Table 4]

Test Test Test Test Test

region 33 region 34 region 35 region 36 region 37

Temperature A of heated mist 45 50 55 55

(°C) Conventional Conditions Treatment time h 6 10 3 6 control (seconds)

Leaf temperature 45 50 52 55 (°C)

Trap 1 49 50 48 47 359

Trap 2 44 39 33 34 100 Species 51 44 44 41 281 population Trap 3 Average species 48 44 42 41 247 population

[0054]

The average species population of Empoasca onukii

was smaller in all test regions 33 to 36 in which a

heated mist was brought into contact with tea plant and

tea leaves than that in the test region in which

conventional control was performed. This shows that

bringing a heated mist into contact with tea plant and

tea leaves has an effect of controlling pests.

Claims

Claims

[Claim 1]

A method for controlling pests of tea, comprising a

treatment to bring a mist of heated water into contact

with tea leaves and tea plant in such a manner that the

temperature of the surface of the tea leaves is 45°C to

550C.
[Claim 2]

The method for controlling pests of tea according to

claim 1, wherein a mist of water adjusted to 45 0 C to 550 C

is brought into contact with tea leaves.
[Claim 3]

The method for controlling pests of tea according to

claim 1 or 2, comprising adjusting the temperature (°C)

of a mist of water to be brought into contact with tea

leaves and the time (seconds) of bringing the mist of

water into contact with the tea leaves such that

{temperature (0C) of mist of water to be brought into

contact with tea leaves - 300C}^ 2 x {time (seconds) of

bringing mist of water into contact with tea leaves}

+ 100 is 50 or less.
[Claim 4]

The method for controlling pests of tea according to

any one of claims 1 to 3, wherein the treatment to bring

a mist of heated water into contact with tea leaves is

carried out within 2 weeks from the time when tea leaves

are plucked or trimmed.
[Claim 5]

The method for controlling pests of tea according to

any one of claims 1 to 3, wherein the treatment to bring

a mist of heated water into contact with tea leaves is

carried out within 24 hours from the time when tea leaves

are plucked or trimmed.
[Claim 6]

The method for controlling pests of tea according to

claim 4 or 5, wherein the plucking of tea leaves is for

harvesting a first crop tea or a second crop tea.
[Claim 7]

The method for controlling pests of tea according to

claim 4 or 5, wherein the trimming is performed after

plucking a first crop tea or after plucking a second crop

tea.
[Claim 8]

A method of producing tea, comprising using the

method for controlling pests of tea according to any one

of claims 1 to 7.