ANNEX 2 TREATMENT - IPPC · 4 → No experiment was conducted to determine the most resistant life stage of the nematode. Commodity/regulated article information － commodity type/cultivar(where

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ANNEX 2 INFORMATION REQUIRED FOR SUBMISSION OF A PHYTOSANITARY TREATMENT The following summary information should be provided (see section 3.1). This cover page is designed to assist the evaluation process. The information required in sections 3.2 and 3.3 should be appended to this cover page. Text in brackets is given explanatory purposes. Name of treatment Methyl Iodide fumigation of wood packaging material for Pine Wood Nematode and Longhorn beetles

Name of NPPO or RPPO

MAFF, Japan

Name of person responsible for the submission of the treatment(contact person);

Mitsuaki KINOSHITA

Position and/or title;

Deputy Director

Affiliation;

Plant Protection Division, MAFF

Complete mailing address;

1-2-1 Kasumigaseki,Chiyoda-ku,Tokyo,100-8950 JAPAN

Phone; +81-3-3502-5978

Fax; +81-3-3502-3386

Email;

[email protected]

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Treatment description Treatment type(e.g. chemical, irradiation, heat, cold); Chemical Target commodity(ies)/regulated article(s)(include taxonomic classification, description of commodity, state of preservation/processing or maturity(e.g. fruit, plants for planting, part of plant, wood), cultivar or variety, intended use, description of regulated article(e.g. ship, container, soil, machinery, wood, silo) as appropriate); Wood packaging material Target pest(s); the identity of the target pest(s) (taxonomic information including strains, biotypes and where appropriate, life stage(s)) Pine wood nematode Bursaphelenchus xylophilus Longhorn beetles Monochamus alternatus(larva,pupa), Arhopalus coreanus(larva) Schedule (include description such as active ingredient, dose, duration and temperature);

Minimum gas concentration Commodity temperature

(℃)

Duration (h)

Maximum

load

factor

(%)

Dose (g/m3) 1h

(g/m3)

4h

(g/m3)

24h

(g/m3)

Minimum

CT

product

(g・h/m3)

25 or above 36 24 14 8 300 20 or above 48 30 16 10 350 15 or above 60 36 18 12 400 10 or above

24

50

84 42 20 14 450 Other information(delivery method, pre/post handling conditions, etc.): The treatment is for tarpaulin or chamber fumigation. An air circulation fan is operated for more than 30 minutes during dosing for gas

uniformity. Gas concentration should be monitored at upper and lower air space（average of the two

values ）. Commodity temp. should be measured just before dosing.

Reason for submission; (describe why the treatment is needed; where a treatment is widely used, include the countries where approved. Also, is it relevant to any existing ISPMs?)

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→ No experiment was conducted to determine the most resistant life stage of the nematode.

Commodity/regulated article information － commodity type/cultivar(where varietal differences impact on treatment efficacy,

data should be provided for all varieties under consideration) → Lumber and boards of red pine (Pinus densiflora) were used for the experiment. → see No.1 report p.1--- Material and Methods ----- Wood Materials infected with Pine Wood Nematode

－ conditions of the commodity, for example: ・ whether it was free from disease/non-target pest infestation or pesticide

residue → The lumbers and boards were free from disease/non-target pest infestation. ・ size, shape, weight, stage of maturity, quality, variety, etc. → lumber: 15cm thick × 15cm wide × 30cm or 40cm long Board: 3cm thick × 15cm wide × 45cm long ・ infested at a susceptible growth stage →The lumber used for the experiment were thought to be in a susceptible growth stage, because they had contained more than 10,000 nematodes per 100g. → see No.1 report p.1--- Material and Methods ----- Wood Materials infected with Pine Wood Nematode

－ type of regulated article －

Experimental parameters － level of confidence provided by the laboratory testing, method of statistical analysis

and the data supporting that calculation (e.g. number of subjects treated, number of replicate tests, control) → see No.1 report p.3----Table 2.

－ experimental facilities and equipment → see No.1 report p.2---- Material and Methods ----- Fumigation----

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Measurements of Gas Concentration, Temperature and Moisture Content---Evaluation of Mortality

－ experimental design (e.g. randomized complete block design)

→ see No.1 report p.3----Table 2 Nematode infected pine lumbers and boards were served to each block（treated and control） at random.

－ experimental conditions (e.g. temperature, relative humidity, diurnal cycle) → All the fumigation tests were conducted in the temperature regulated fumitron

(= specially designed air conditioned room for fumigation test). － monitoring of critical parameters(e.g. exposure time, dose, temperature (target

commodity and air), relative humidity) → see No.1 report p.2---Table 1 and p.3---Fig.1

－ methodology to measure the effectiveness of the treatment (e.g. whether mortality

is the proper parameter, whether the end-point mortality was assessed at the correct time, mortality or sterility of treated and control group) → see No.1 report p.2----Material and Methods ---Evaluation of Mortality

－ determination of efficacy over a range of critical parameters, where appropriate,

such as exposure time, dose, temperature, relative humidity and water content. → see No.1 report--- Table 1(p.2), No.1 Report---Table 2(p.3) and No.1 Report---

Fig.2(p.4). also see No.1 report p.4------Results and Discussion---- Mortality of Pine Wood Nematode----Relationship between Mortality and CT products

3.2.2 Efficacy data using operational conditions Pest information － identity of the pest to the appropriate level (e.g. strain, biotype, physiological race

and life stage, laboratory or field strain) →Bursaphelenchus xylophilus, 3rd stage larvae, field strain(from Red pine wood grown in Ibaraki prefecture, Japan) Monochamus alternatus, Alhoalus rusticus, larvae and pupae, field strain(from Red pine wood grown in Ibaraki prefecture, Japan)

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→see No.2 Report p.7-8 --- Material and Methods ----- Test Wood Packing Materials Pine Wood Nematode ----- Japanese Pine Sawyer and Far East Rusty Longicorn Beetle

－ conditions under which the pests are cultured/reared or grown →The pest infested lumber and logs were stored at fumigation temperature for 2 to 4 days. → see No.2 Report p.7-8 --- Material and Methods ----- Test Wood Packing Materials Pine Wood Nematode ----- Japanese Pine Sawyer and Far East Rusty Longicorn Beetle

－ biological traits of the pest relevant to the treatment(e.g. viability, genetic

variability, weight, developmental time, fecundity, freedom from disease or parasites) → No data

－ method of natural/artificial infestation

The pest infested red pine was collected from the field for the experiment. → see see No.2 report p.7-8 --- Material and Methods ----- Test Wood Packing Materials Pine Wood Nematode----- Japanese Pine Sawyer and Far East Rusty Longicorn Beetle)

－ determination of most resistant species/life stage(in the commodity where

appropriate) → No experiment was conducted to determine the most resistant species/life stage of the pests.

Commodity/regulated article information － commodity type/cultivar(where varietal differences impact on treatment efficacy,

data should be provided for all varieties under consideration) → Lumber and logs of red pine (Pinus densiflora) were used for the experiment. It is known that the fumigant sorption ability of red pine wood is greater than that of radiate pine or american pine. → see No.2 report p.7-8 --- Material and Methods ----- Test Wood Packing Materials Pine Wood Nematode---- Japanese Pine Sawyer and Far East Rusty Longicorn Beetles.

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－ conditions of the commodity, for example: ・ whether it was free from disease/non-target pest infestation or pesticide residue → The lumber and logs were free from disease/non-target pest infestation.

・ size, shape, weight, stage of maturity, quality, variety, etc. → lumber: 10 - 15cm thick × 10 - 15cm wide × 50cm long log: 10 - 15cm diameter × 100cm long ・ infested at a susceptible growth stage →The lumber and logs used for the experiment were thought to be in a susceptible growth stage, because they had been naturally infested in the field. → see No.2 report p.7-8 --- Material and Methods ----- Test Wood Packing Materials Pine Wood Nematode

－ type of regulated article －

Experimental parameters － level of confidence provided by the laboratory testing, method of statistical analysis

and the data supporting that calculation (e.g. number of subjects treated, number of replicate tests, control) → see No.2 report p.10---Table 1 and p.11---Table 3

－ experimental facilities and equipment → see No.2 report p.8-9------Material and Methods ----- Fumigation Schedules and Fumigation---Measurements of Temperature, Gas Concentration and Moisture Content-----Evaluation of Mortality

－ experimental design (e.g. randomized complete block design)

→ see No.2 report p.10---Table 1 and p.11---Table 3 Pest infected pine lumber and logs were served to each block（treated and control） at random.

－ experimental conditions (e.g. temperature, relative humidity, diurnal cycle) → The fumigation tests with tarpaulin sheet were conducted in two air

conditioned chambers ( 175m3, 68 m3).

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－ monitoring of critical parameters(e.g. exposure time, dose, temperature (target commodity and air), relative humidity)

→ see No.2 report p.11---Table 2 , p.9---Fig.1 and p.10---Fig.2 － methodology to measure the effectiveness of the treatment (e.g. whether mortality

is the proper parameter, whether the end-point mortality was assessed at the correct time, mortality or sterility of treated and control group) → see No.2 report p.9 ---Material and Methods ---Evaluation of Mortality

－ determination of efficacy over a range of critical parameters, where appropriate,

such as exposure time, dose, temperature, relative humidity and water content. → see No.2 report p.9---Table 1 and p.12---Table 3

Also. see No.2 report p.10-12---Results and Discussion---- Mortality of Pine Wood Nematode, Residual Gas Ratio and CT Product----Mortality of Longhorn Beetles

－ factors that affect the efficacy of the treatment ( packaging, packing method, stacking, timing of treatments, pre/post packaging or processing, in transit, on arrival). The circumstances of the treatment should be stated, for example the efficacy of a treatment may be affected by packaging, and data should be provided to support all the circumstances that are applicable.

→ Load affect the efficacy of the treatment. The experiment was conducted with 51.2%(v/v) loading.

－ monitoring of critical parameters(dose, temperature(commodity and air), relative

humidity). For example: ・ the number and placement of gas sampling lines(fumigation) → Number:3 lines

Placement: Air space (upper), Air space (Lower) and Center of loading ・ the number and placement of temperature/humidity sensors. → Number:1 point (commodity temp.)

Placement: Center of loading In addition, any special procedures that affect the success of the treatment (e.g. to maintain quality of the commodity) should also be included.

3.3 Information on commercial feasibility and applicability － Feasibility of carrying out the phytosanitary treatment (includes ease of use, risks to

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operators, technical complexity, training required, equipment required, cost) → As an application method is as same as methyl bromide, operators who are familiar

with methyl bromide can easily handle Iodomethane for fumigation. It means they can use same equipment and similar leak checkers, detectors and protection materials.

－ Extent to which other NPPOs have approved the treatment as a phytosanitary

measure, if known → Not yet approved. － Availability of expertise needed to apply the phytosanitary treatment internationally → As above mentioned, application method of this treatment is as same as methyl

bromide, of which expertise is well known internationally. － Versatility of the phytosanitary treatment (e.g. application to a wide range of

countries/pests/commodities) → In addition to nemaodes (Bursaphelenchus xylophilus), Iodomethane control all

stage (i.e., egg, larva, pupa and adult) of other insects such as Cerambycidae, Bostrichidae and Curculionidae on domestic and imported logs/timbers.

－ the degree to which the phytosanitary treatment complements other treatments or

procedures (e.g. potential for the treatment to be used as part of a systems approach for one pest or to complement treatments for other pests) → As Iodomethane control 100% of every target pests listed above, no system

approach nor complement treatments is required. － feasibility of having the phytosanitary treatment accepted at the international level → An international pesticide company has been developing Iodomethane to substitute

methyl bromide internationally; including but not limited to NAFTA, central and south America, Australia and Japan.

－ consideration of potential non-target effects (e.g. impacts to environment, to

non-target organisms) → Iodomethane has been reviewed for its potential as a ozone depleting substance and

been found to pose no threat to ozone depletion. In the Risk Assessment recently published by the US EPA / Stratospheric Protection division have concluded the

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ozone depletion potential for iodomethane to be 0.0015 compared to methyl bromide at 0.36 with 0.2 being the minimum amount for inclusion in the Montreal Protocol for substances known to deplete ozone.

－ Applicability of treatment with respect to specific commodity/pest combinations → Iodomethane controls a broad range of soil-borne diseases, nematodes, weeds and

fungi as a soil fumigant. Additionally, as post harvest fumigation, it controls weevil/curculio on chestnuts.

－ commercial relevance → An international pesticide company has been developing Iodomethane globally as a

soil fumigant to substitute methyl bromide. An international pesticide company has been developing Iodomethane to substitute methyl bromide internationally; including but not limited to NAFTA, central and south America, Australia and Japan. An international pesticide company has been developing Iodomethane globally as, including but not limited to, a soil, timber and wood package fumigant. An international pesticide company has secured a volume supply of iodine that we believe is sufficient to meet our demand requirements. Efforts are also underway to generate additional reserves that will allow for greater uses of iodomethane in the future.

－ technical viability → According to NFPA (National Fire Protection Association) hazard codes and HMIS

(Hazardous Materials Information System) hazard codes, Iodomethane is categorized as follows;

Flammability: 1(flash point above 200F) Reactivity: 0 (stable)

－ human and animal health and safety → Acute: Eye Irritation: Severe with corneal effects >21 days Skin Irritation: Moderate at 72 hours

Skin Sensitization: Negative (M/K Maximization test) Dermal Toxicity: LD50 (dermal) rabbit: >2,000mg/kg Oral Toxicity: LD50 (oral) rat = 80 mg/kg (male); 132mg/kg(female)

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LD50 (oral) mouse = 155mg/kg (male); 214mg/kg(female) Inhalation Toxicity: LC50 (inhalation; 4-hr vapor) rat = 691ppm (4mg/L)

Neurotoxicity: The acute neurotoxicity of Iodomethane was evaluated in 12 male and female rats per group exposed to 0, 25, 100, or 400 ppm Iodomethane via inhalation for 6 hours on a single day. Adverse effects were observed in the 100 and 400 ppm exposure group, but not in the 25 ppm exposure group. Effects included: repetitive movement of the mouth and jaws, drooping eyelids, increased salivation, abnormal gait, decreased arousal, uncoordinated air righting reflexes, decreased motor activity, and no startle response (in the 400 ppm group). An increase in incidence and severity of adverse effects was evident with increasing dose between the 100 ppm and 400 ppm exposed rats. NOEL was 25 ppm.

Subchronic: In a study with rats exposed to Iodomethane vapor at concentrations of 5, 20 or 70 ppm for six hours per day, five days per week for thirteen weeks, treatment-related effects occurred only at the high dose level. Treatment-related effects included decreased body weight gain, alterations in the nasal epithelium, and increased serum cholesterol. An increase relative liver weights of females exposed to 70ppm was identified but not considered toxicologically significant. NOAEL for whole-body inhalation exposure to Iodomethane in rats for 13 weeks was 20ppm.

Tolerances: Tolerances are not required for Iodomethane in EPA. Although iodomethane is used as an agricultural pesticide, it is considered a non-food use chemical since it is quickly degraded or metabolized and subsequently incorporated into natural plant constituents.

－ commodity quality. → After treatment of Iodomethane, no phytotoxicity / chemical injury observed on

wood packaging material.

E#ects of Some Fumigants on Mortality of the PineWood Nematode, Bursaphelenchus xylophilus

Infesting Wooden Packages

6. Mortality of Pine Wood Nematode and Longhorn Beetles by

Methyl Iodide Tarpaulin Fumigation

Yukihiro SDB6, Hitoshi KDB6IHJ,� Yutaka A7:,�� Toru II676H=>,��Yasuo M6IHJBDID� and Fusao K6L6@6B>�

Research Division, Yokohama Plant Protection Station, 1�16�10, Shin-yamashita, Naka-ku,

Yokohama 231�0801, Japan, �Research Laboratory, Japan Fumigation Technology

Association, Tokyo and ��MITC Research Group, Tokyo

Abstract: Mortality test was conducted with methyl iodide (MI 50�w/w, carbon dioxide 50�w/w) to

confirm CT products for complete mortality of the pine wood nematode, Bursaphelenchus xylophilus infest-

ing red pine lumber (10�15 cm thick�10�15 cm wide�50 cm long in size) and the Japanese pine

sawyer, Monochamus alternatus, and the Far East rusty longicorn beetle, Arhoalus rusticus infesting red

pine logs (10�20 cm diameter, 1 m long). The test and filler material were fumigated at di#erent temper-

atures and doses for 24 hours with 51.2� loading under a tarpaulin sheet of 1.95 m3. Complete mortali-

ty of the nematode was attained at each of 84 g/m3 at 10�, 60 g/m3 at 15�, 64 g/m3 at 20� and 48

g/m3 at 25�, while some survivors of the pine wood nematode were confirmed at 36 g/m3 at 25� in

one of four replicate tests, because of delayed gas uniformity caused by breakdown of a gas circulation

fan. Complete mortality of larvae and pupae of longhorn beetles was attained at each of 84 g/m3 at

10�, 60 g/m3 at 15�, and 36 g/m3 at 25�. MI fumigation schedules for the tarpaulin sheet fumiga-

tion are at 84 g/m3 at 10�14.9�, 60 g/m3 at 15�19.9�, 48 g/m3 at 20�24.9� and 36 g/m3 at 25� or

above for 24 hours with 50� or below loading.

Key words: quarantine treatment, methyl iodide, fumigation, mortality, CT product, tarpaulin sheet,

Bursaphelenchus xylophilus, Monochamus alternatus, Arhoalus rusticus, wood packing material

Introduction

Methyl bromide fumigation schedules for the pine wood nematode, Bursaphelenchusxylophilus infesting red pine packing material have already been proposed based on test data(SDB6 et al., 2001, 2002, 2003; K6L6@6B> et al., 2004).

Further, SDB6 et al. (2005) conducted susceptibility test on the pine wood nematode, and gassorption test of wood packing material using methyl iodide (MI) as an alternative fumigant ofmethyl bromide in a 29.5-liter fiberglass fumigation box. They proposed MI fumigation sched-ules for warehouse and tarpaulin sheet fumigation based on data that complete mortality of thepest was attained at 60 g/m3 at 10�, 40 g/m3 at 15 and 20�, and 30 g/m3 at 25�, and CT prod-ucts for complete mortality were 450 mg�h/l at 10�, 400 mg�h/l at 15�, 350 mg�h/l at 20�and 300 mg�h/l at 25�, respectively for 24 hours with 25� (v/v) loading.

Here we report the result of mortality confirmatory tests for the pine wood nematode, theJapanese pine sawyer, Monochamus alternatus and the Far East rusty longicorn beetle, Arhoalusrusticus that may be found in wood packing material.

Materials and Methods

Test Wood Packing MaterialPine Wood Nematode

Red pine, Pinus densiflora naturally infested with the pine wood nematode, Bursaphelenchusxylophilus (SI:>C:G and BJ=G:G) N>8@A:> was collected in Ibaraki Prefecture in March to July

R:H. BJAA. PA. PGDI. J6E6C No. 42: 7�13 (2006)

2004 and March to May 2005. A log was sawed into lumber (10�15 cm thick�10�15 cm wide�50 cm long). Lumber infested with more than 10,000 nematodes per 100 g of sample was usedfor the mortality test. The lumber was stored for two to four days at fumigation temperaturesuntil testing.

Japanese Pine Sawyer and Far East Rusty Longicorn BeetleRed pine logs (10�15 cm diameter�100 cm long) naturally infested with larvae and pupae of

the Japanese pine sawyer, Monochamus alternatus HDE: and the Far East rusty longicorn beetle,Arhoalus rusticus (L>CC6:JH) were collected in Ibaraki Prefecture in March to May 2005, and thenthey were stored for two to four days at fumigation temperatures until testing.

Fumigation Schedules and FumigationThe following fumigation schedules (SDB6 et al., 2005) were applied for fumigation.

Fumigation was conducted under a tarpaulin sheet in an air-conditioned fumigation cham-ber. MI (MI 50�, CO2 50�) filled in a high-pressurized gas cylinder was used for fumigation.This type of MI was registered as agricultural chemical for logs infested with forest insect pestsin Japan in 2005.

Filler red pine lumber (15 cm thick�15 cm wide�100 cm long, 21 lumber; and 10 m thick�10 cm wide�100 cm long, 5 lumber) and board (3 cm thick�15 cm wide�100 cm long, 87 boards;and 2 cm thick�10 cm wide�100 cm long, 43 boards) were loaded in the size of 1m3 (1 m�1 m�1 m). Test lumber infested with the nematode was placed in the center of the load. The red pinelog infested with the Japanese pine sawyer and the Far East rusty longicorn beetle was alsoplaced on top of the load. A plastic pipe frame (1.25 m�1.25 m�1.25 m) was placed over theload, and then the frame was covered with an EVOH sheet (Variastar�) of 0.1 mm thickness.Sand snakes were placed on the sheet skirt to prevent gas leakage. The capacity of the tarpaulinsheet was 1.95 m3, and the load factor of wood material was 51.2� (v/v) in the test.

A gas dosing Teflon pipe and temperature sensors were fixed to upper and lower places inair space and between lumber of the load. A small-size air circulation fan was placed under the tar-paulin sheet. MI was introduced to the sheet by connecting a stainless steel pipe fixed to the toplayer of the load. A gas circulation fan was operated for 30 minutes during dosing. Fumigationwas conducted for 24 hours. The air-fumigant mixture was exhausted for one hour after fumiga-tion. Fumigated material was placed in netted bags and was stored at ambient temperature untilthe evaluation of mortality.

Measurements of Temperature, Gas Concentration, and Moisture ContentTemperature was monitored with an automatic temperature recorder (Hybrid recorder AH,

Chino). Gas concentration during fumigation was monitored at time intervals of 1, 2, 4 and 24hours after dosing with gas chromatography (FID, Shimazu). The residual gas ratio was calculat-ed with the following formula;

Residual gas ratio (�)� 100�gas concentration after 24 hour fumigation (mg/l)applied dose (g/m3)

CT product was calculated with the following formula;

Temperature(�)

Exposure time(h)

Load factor(�)

DoseCT product

(mg�h/l)Warehouse(g/m3)

Tarpaulin(g/m3)

10�14.9 24 50 84 112 45015�19.9 24 50 60 80 40020�24.9 24 50 48 64 35025 or above 24 50 36 48 300

R:H. BJAA. PA. PGDI. J6E6C No. 428

CT product (mg�h/l)�1.5C1�1.5C2�11C4�10C24

(where Cx is the gas concentration after x hour fumigation).

Moisture content was measured by the weight di#erence of samples of lumber and boardpieces before and after drying at 115� for 18�24 hours. Moisture content of filler lumber andboard was 13.6�3.4�.

Evaluation of MortalityThe number of nematodes was confirmed using wood sample before fumigation and sample

for evaluation of mortality at six to seven days after fumigation. Small pieces from a few placesper fumigated or non-fumigated lumber and board were cut o# at a still smaller size (3 mm�3mm�5 mm) with a special designed cutting instrument and scissors. The nematode wasdetected by the Bermann funnel method. A 20�40 g of sample was placed in a funnel and thenthe sample was stored for 48 hours at room temperature. The number of surviving nematodeswas counted under a microscope. The longhorn beetle was also evaluated by dissecting infestinglogs at seven days after fumigation.

Results and Discussion

Progressive Gas Concentration of MIFigure 1 shows average progressive MI concentrations, as a typical example, in four replicate

tests fumigated at 80 g/m3 at 15� with 51.2� loading. No di#erence was observed on gas concen-trations between upper and lower places in the air space just after dosing. A 16�22� di#erencein gas concentration was confirmed between air space and the center of the load in the first 15minutes to four hours after dosing, and then the di#erence became small gradually. The smalldi#erence of gas concentration would be caused by two conditions of both operation of a circula-tion fan for 30 minutes during dosing and rapid evaporation and di#usion of particulate MI dis-solved to carbon dioxide.

Fig. 2 shows average progressive MI gas concentrations at the center of the load during fumiga-tion for 24 hours with 51.2� loading. Gas concentrations at one to four hours during dosingdecreased with the same rate at each applied dose at di#erent temperatures. However, gas concen-trations at the end of fumigation of 24 hours were low at lower temperatures. The gas reductionduring fumigation was almost the same result of the test in the 100-liter fiberglass fumigationbox (SDB6 et al., 2005).

Fig. 1. Progressive gas concentrations for red pine packing materialfumigated at 80 g/m3 of methyl iodide at 15� with 51.2� loading(an air circulation fan was operated for 30 minutes during dosing).

March, 2006 SDB6 et al.: Mortality of Pine Wood Nematode by Methyl Iodide Fumigation 9

Mortality of Pine Wood Nematode, Residual Gas Ratio and CT ProductTables 1 and 2 show mortality of the pine wood nematode and gas concentration at the end

of fumigation, residual gas ratio and CT products for the pine wood nematode fumigated at di#er-ent temperatures and doses for 24 hours with 51.2� loading.

Residual gas ratios of MI were 14.8�29.6�, which were lower than the 24.5�45.0� from the

Fig. 2. Progressive gas concentrations for red pine packing materialsfumigated with methyl iodide with 51.2� loading for 24 hoursunder a tarpaulin sheet.

Table 1. Mortality data for the pine wood nematode infesting red pine packing material fumigated with methyliodide for 24 hours with 51.2� (v/v) loading under a tarpaulin sheet.

Temper-ature

(�)

Dose(g/m3)

ReplicateNo. of test

lumber1)

Before fumigation After fumigation

Moisturecontent2)

(�)

Weight ofsample3)

(g)

No. ofnematode4)

per 100 g

Moisturecontent2)

(�)

Weight ofsample3)

(g)

No. ofnematode4)

per 100 g

Survivor(�)

10

84 2 6 29.8 186 23,600 24.4 1,189 0 0

96 1 3 19.4 58 72,100 18.8 602 0 0

112 1 3 19.4 58 72,100 19.6 603 0 0

Cont. � 7 25.3 181 41,300 16.0 134 15,600 37.8

15

60 2 8 28.8 183 23,700 16.5 1,655 0 0

80 4 12 20.3 550 42,200 20.8 2,453 0 0

Cont. � 13 23.7 385 41,100 18.5 288 40,700 99.0

2064 2 6 31.8 122 20,400 23.3 1,001 0 0

Cont. � 4 31.2 81 21,100 21.8 142 21,700 102.8

25

3615) 3 30.4 92 23,400 22.0 587 1.2 0.005

3 9 31.0 276 23,900 22.0 1,793 0 0

48 2 6 18.6 123 168,200 17.1 1,196 0 0

Cont. � 7 26.2 184 86,900 18.6 243 70,300 80.9

1) Size of lumber: 10�15 cm thick�10�15 cm wide�50 cm long.2) Average moisture content in test lumber.3) Weight of wood samples used to detect nematode.4) Number of survivors of the pine wood nematode.5) No circulation fan during fumigation.

R:H. BJAA. PA. PGDI. J6E6C No. 4210

test in a 100-liter box with 25� loading (SDB6 et al., 2005), because of a high load factor of51.2� and low air tightness of the tarpaulin sheet. Residual gas ratios were low at low fumiga-tion temperatures, which tendency was almost the same as the result from a 100-liter box. Ahigher gas sorption ratio would be caused at lower fumigation temperatures.

Complete mortality was attained at each of 112 g/m3 at 10�, 80 g/m3 at 15�, 64 g/m3 at20� and 48 g/m3 at 25� in the schedule for tarpaulin sheet fumigation, and at each of 84 g/m3

at 10� and 60 g/m3 at 15� in the schedule for warehouse fumigation, respectively, while some sur-vivors (0.005�) of the pine wood nematode were confirmed at 36 g/m3 at 25� in one of four repli-cate tests, because of delayed gas uniformity caused by breakdown of a gas circulation fan.

Further, some survivors (0.33�9.0 nematodes per 100 g of wood sample) of free-living nema-tode (Rhabditidae Gen. et sp. and Plectidae Gen. et sp.) were confirmed in all of the fumigation sched-ules that attained complete mortality of the pine wood nematodes. These surviving free-living nem-atodes could be disregarded in the mortality test, as they are non-quarantine pests.

CT products were 846 mg�h/l at 112 g/m3 at 10�, 548 mg�h/l at 80 g/m3 at 15�, 481 mg�h/l at 64 g/m3 at 20� and 444 mg�h/l at 48 g/m3 at 25� by the schedule for tarpaulin sheetfumigation, and 518 mg�h/l at 84 g/m3 at 10� and 467 mg�h/l at 80g/m3 at 15� by the sched-ule for warehouse fumigation, respectively. These CT products were higher than those (450 mg�h/l at 10�, 400 mg�h/l at 15�, 350 at 10�, and 300 mg�h/l at 25�) from the schedule for a tarpau-lin fumigation proposed by SDB6 et al. (2005).

In fumigation at 36 g/m3 at 25�, CT products from two replicates in four replicate testswere lower (265 and 273 mg�h/l) than that (300 mg�h/l) for complete mortality (SDB6 et al.,2005). Some survivors of the pine wood nematode were observed on fumigation with CT prod-uct of 265 mg�h/l (Table 1) and the low CT product was caused by delayed gas uniformity at the be-ginning of fumigation, because of breakdown of a gas circulation fan. Therefore, it would be essen-tial to operate a gas circulation fan for more than 30 minutes at the beginning of fumigation.

Mortality of Longhorn BeetlesTable 3 shows the mortality of the Japanese pine sawyer and the Far East rusty longicorn

beetle fumigated at di#erent temperatures and doses for 24 hours with 51.2� loading. Completemortality of larvae and pupae of the pest in xylem was attained at each of 84 g/m3 at 10�, 60 g/

Table 2. Residual gas concentration, residual gas ratio and CT product for the red pine infested with the pine woodnematode fumigated with methyl iodide at 24 hours with 51.2� (v/v) loading under a tarpaulin sheet1).

Temperature(�)

Dose(g/m3)

Replicate

Residual gasconcentiation2) Ratio of

residualgas3)

CT product4)

Average(mg/l)

Minimum(mg/l)

Average(mg�h/l)

Minimum(mg�h/l)

10

84 2 12.5 12.3 14.8 521 518

96 1 15.6 � 16.3 605 �

112 1 20.5 � 18.3 846 �

1560 2 11.4 11.1 19.0 472 467

80 4 15.9 13.4 19.9 645 548

20 64 2 14.1 13.5 22.0 519 481

2536

15) 7.5 � 20.8 265 �3 8.6 7.2 23.9 322 273

48 2 14.2 13.2 29.6 483 444

1) Wood packing material was loaded in the size of 1 m3.2) Gas concentration at the center of loading.3) 100�gas concentration after 24 hours fumigation (mg/l)/applied dose (g/m3).4) 1.5C1�1.5C2�11C3�10C24 �Cx: gas concentration after x hours).5) No circulation fan during dosing.

March, 2006 SDB6 et al.: Mortality of Pine Wood Nematode by Methyl Iodide Fumigation 11

m3 at 15�, 64 g/m3 at 20� and 36 g/m3 at 25�, respectively.

Proposed MI Fumigation Schedule and Fumigation MethodThe pine wood nematode, the Japanese pine sawyer and the Far East rusty longicorn beetle

were killed completely by a proposed MI fumigation schedule as shown in Table 4, that is, at 84g/m3 at 10�14.9�, 60 g/m3 at 15�19.9�, 48 g/m3 at 20�24.9� and 36 g/m3 at 25� or above for24 hours with 50� or below loading. In tarpaulin sheet fumigation, a gas circulation fan for gas uni-formity should be operated to obtain a minimum gas concentration at 1, 4 and 24 hours, and CTproduct for complete mortality of the target pest.

References Cited

K6L6@6B>, F., Y. SDB6, H. KDB6IHJ and Y. M6IHJBDID (2004) E#ects of Some Fumigants on the Pine WoodNematode, Bursaphelenchus xylophilus Infesting Wooden Packages. 4. Mortality and CT Product in MethylBromide Fumigation with High Loading of Wood Packing Materials. Res. Bull. Pl. Prot. Japan 40: 7�12.

SDB6, Y., H. N6>ID, T. M>HJB>, M. M>OD7J8=>, Y. THJ8=>N6, I. M6IHJD@6 and F. K6L6@6B> (2001) E#ects of SomeFumigants on the Pine Wood Nematode, Bursaphelenchus xylophilus Infesting Wooden Packages.1. Susceptibility of Pine Wood Nematode to Methyl Bromide, Sulfuryl Fluoride and Methyl Isothiocyanate.Res. Bull. Pl. Prot. Japan 37: 19�26.

SDB6, Y., H. N6>ID, T. M>HJB>, Y. THJ8=>N6, M. M>OD7J8=>, I. M6IHJD@6 and F. K6L6@6B> (2002) E#ects of SomeFumigants on the Pine Wood Nematode, Bursaphelenchus xylophilus Infesting Wooden Packages.2. Mortality of Pine Wood Nematode by Methyl Bromide Tent Fumigation. Res. Bull. Pl. Prot. Japan 38:13�19.

SDB6, Y., M. GDID, N. O<6L6, H. N6>ID and F. K6L6@6B> (2003) E#ects of Some Fumigants on the Pine WoodNematode, Bursaphelenchus Xylophilus Infesting Wooden Packages. 3. Mortality and Fumigation Stan-dards for Pine Wood Nematode by Methyl Bromide. Res. Bull. Pl. Prot. Japan 39: 7�14.

SDB6, Y., M. GDID, N. O<6L6, H. N6>ID and K. H>G6I6 (2005) E#ects of Some Fumigants on the Pine Wood Nem-atode, Bursaphelenchus xylophilus Infesting Wooden Packages. 5. Mortality of Pine Wood Nematode andFumigation Standards by Methyl Iodide. Res. Bull. Pl. Prot. Japan 41: 1�7.

Table 3. Mortality data for two species of longhorn beetle infesting red pine packing material fumigated withmethyl iodide at 24 hours with 51.2� (v/v) loading under a tarpaulin sheet.

Temper-ature�

Repli-cate

Dose(g/m3)

No. oftestlog1)

Monochamus alternatus1) Arhoalus rusticus1)

Larva Pupa Larva

n SurvivorMortality

(�)n Survivor

Mortality(�)

n SurvivorMortality

(�)

10 2 84 12 71 0 100 22 0 100 55 0 10015 2 60 12 70 0 100 4 0 100 32 0 10020 2 64 16 106 0 100 1 0 100 � � �25 3 36 14 96 0 100 9 0 100 87 0 100

Cont. 3 � 8 65 59 9 5 5 0 23 23 0

1) Number of survivors of the longhorn beetle was confirmed by dissecting red pine log.

Table 4. Proposed methyl iodide fumigation schedule for wood packing material infested with the pine woodnematode under a tarpaulin sheet.

Temperature(�)

Time(h)

Load factor(�)

Dose(g/m3)

Minimum gas concentration MinimumCT product

(mg�h/l)1 h

(mg/l)4 h

(mg/l)24 h

(mg/l)

10�14.9

24 50 or below

84 42 20 14 45015�19.9 60 36 18 12 40020�24.9 48 30 16 10 35025 or above 36 24 14 8 300

�The longhorn beetle is also killed completely by the fumigation standard.�An air circulation fan is operated for more than 30 minutes for gas uniformity.

R:H. BJAA. PA. PGDI. J6E6C No. 4212

和 文 摘 要

マツノザイセンチュウ Bursaphelenchus xylophilus が寄生した梱包材のくん蒸剤による消毒試験

6. ヨウ化メチルを用いたマツノザイセンチュウ及びカミキリムシの天幕くん蒸試験

相馬幸博�小松 仁��阿部 豊���板橋 享���松本安生��川上房男�横浜植物防疫所調査研究部��社団法人 日本くん蒸技術協会���MITC研究会

ヨウ化メチルくん蒸剤 �ヨウ化メチル 50�� 炭酸ガス 50�; w/w� を用い� マツノザイセンチュウが寄生した赤松梱包材 (10�15 cm�10�15 cm�50 cm) 並びにマツノマダラカミキリ及びサビカミキリが寄生した赤松材 �直径 10�20 cm�1 m� を収容率 51.2� で24時間天幕くん蒸 �内容積 1.95 m3� を行い� くん蒸中のガス濃度 �CT値� 及び殺虫効果を調査した� その結果� マツノザイセンチュウは 10 84 g/m3� 1560 g/m3� 20 64 g/m3 及び 25 48 g/m3 で完全殺虫された� しかし� 25 36 g/m3 では 4反復試験のうち 1反復において生存虫が認められた �生存率

0.005��� 生存虫が認められたのは� くん蒸中にかくはん機が稼働しなかったためガスの拡散が遅れ� ガス濃度の均一化が遅れたのが原因であった� マツノマダラカミキリ及びサビカミキリの幼虫及び蛹は 10 84 g/

m3� 15 60 g/m3 及び 25 36 g/m3 で完全に殺虫された� これらの結果から� 梱包材に寄生するマツノザイセンチュウ� カミキリムシ類は� 10�14.9 で 84

g/m3� 15�19.9 で 60 g/m3� 20�24.9 で 48 g/

m3 及び 25 以上で 36 g/m3� 収容率 50� 以下� 24

時間くん蒸により完全殺虫されるものと考える�

March, 2006 SDB6 et al.: Mortality of Pine Wood Nematode by Methyl Iodide Fumigation 13

RES. BULL. PL. PROT. JAPAN No. 41: 1～7（2005）

Effects of Some Fumigants on Mortality of Pine Wood Nematode,Bursaphelenchus xylophilus Infecting Wooden Packages

5. Mortality of Pine Wood Nematode and Fumigation Standards by Methyl Iodide

Yukihiro SOOMMAA, Mutsuro GOOTTOO*, Noboru OGGAAWWAA, Hiromitsu NAAIITTOO and Kenji HIIRRAATTAA

Research Division, Yokohama Plant Protection Station

1-16-10, Shin-yamashita, Naka-ku, Yokohama 231-0801, Japan

Abstract:Mortality tests were conducted in a large-scale applied test with methyl iodide（MI）to confirm

complete mortality and CT products for the pine wood nematode, Bursaphelenchus xylophilus（STEINER and

BUHRER）NICKLEI. Red pine lumber（15 cm thick×15 cm wide×30 cm long in size）infected with the

pine wood nematode were fumigated at different doses of MI at different temperatures for 24 hours with

25 and 50% loading. No surviving nematode was observed on samples fumigated at 60 g/裙 at 10℃, 40g/裙

at 15 and 20℃ and at 30g/裙 at 25℃, respectively. The CT product for complete mortality was estimated

to be 450 mg・h/褄 at 10℃, 400 mg・h/褄 at 15℃, 350 mg・h/褄 at 20℃ and 300 mg・h/褄 at 25℃,

respectively. Applied doses of MI were required for warehouse and tarpaulin fumigation, that is, at each of

84g/裙 at 10℃, 60g/裙 at 15℃, 48 g/裙 at 20℃and 36g/裙 at 25℃ in warehouse fumigation and 112g/裙

at 10 ℃, 80g/裙 at 15℃, 64g/裙 at 20℃ and 48g/裙 at 25℃ in tarpaulin fumigation, respectively under con-

ditions of 24-hour fumigation with 50% loading of wood packing materials.

Key words: quarantine treatment, fumigation, methyl iodide, Bursaphelenchus xylophilus, CT product, fumi-

gation standards, wood packing material

Introduction

The Chinese plant quarantine authority has accepted hot air treatment as the only control meas-ure against the pine wood nematode, Bursaphelenchus xylophilus（STEINER and BUHRER）NICKLEI, whichhas potential to infect conifer wood packing materials for export to China from Japan（PublicNotice No. 32, Bureaus of Immigration and Quarantine, Republic of China, November 1, 1999）.

SOMA et al.（2001, 2002）and KAWAKAMI et al.（2004）proposed methyl bromide fumigation sched-ules based on mortality testing against the pine wood nematode infecting red pine boards and lum-ber for packing materials. Methyl bromide, however, as an ozone depleting substance may be limit-ed for the use in the future, although use for quarantine treatment has been excepted from restric-tion of the Montreal Protocol.

Here we report the result of the mortality tests against the pine wood nematode by fumigationwith methyl iodide（MI）which is one of halogen compounds as an alternative to methyl bromide.

Materials and Methods

Wood Materials infected with Pine Wood NematodeRed pine, Pinus densiflora naturally infected with the pine wood nematode were collected in

Ibaraki Prefecture in April 2002 and 2003. The red pine was sawed into lumber（15 cm thick×15cm wide×30 cm and 40 cm long in size）and into boards（3 cm thick×15 cm wide×45 cm long insize）. The red pine lumber with more than 10,000 nematodes per 100g of a sample with the 3rdstage larvae was used for the mortality test. The pine lumber and board were also used for gasabsorption test.

* Hiroshima Sub-station Kobe Plant Protection Station

2

Fumigation The test lumber and board were stored at fumigation temperatures for 1 to 3 days and then

they were placed in 29.5-liter fiberglass fumigation box equipped with a circulation fan, ventilationapparatus, and ports for gas application and sampling, a manometer and temperature probes.

Several doses of MI liquid（purity 99% or more）collected by a gas-tight syringe were placed ina petri dish in the fumigation box. Fumigation tests were conducted at 10, 15, 20 and 25℃ for 24hours with 25 and 50%（v/v）loading. Air-fumigant mixture was exhausted for one hour afterfumigation. Fumigated wood materials were placed in netted bags and stored at ambient tempera-ture until detection of the nematode by the Bermann funnel method.

Measurements of Gas Concentration, Temperature and Moisture Content Gas concentrations during fumigation were monitored with gas chromatography（FID, Shimazu）

and temperatures were also monitored with an automatic temperature recorder（Hybrid recorderAH, Chino）. The wood pieces of lumber and boards were used to measure moisture content,which was determined by the difference in weight of a sample before and after drying at 120℃ for24 hours. CT product（mg・h/褄）was calculated by the following formula; CT product ＝C1 + 2C2

+ 2C4 + 10C6 + 9C24（where, Cx is gas concentration after X hours of fumigation）.

Evaluation of MortalityThe number of the nematodes was confirmed on samples before the fumigation mentioned above

and on those for evaluation of mortality in 6-7 days after fumigation. Wood pieces from a few placesof fumigated or untreated control lumber were collected by sawing and then they were cut to sizeof 3 mm×3 mm×5 mm with scissors. A sample of 30-40g per place was detected by the Bermannfunnel method for 48 hours at room temperature, and then the number of surviving nematodes wascounted under a microscopes.

Results and Discussion

Gas Concentrations during Fumigation in Mortality TestsTable 1 shows MI gas concentrations at the end of fumigation, remaining gas ratios and CT

products fumigated with several doses at 10, 15, 20 and 25 ℃for 24 hours with 25% loading.Fig. 1 also shows progressive gas concentrations for attaining complete mortality for the pine

RES. BULL. PL. PROT. JAPAN No. 41

Table １. Residual gas concentrations，ratios of residual gas and CT products for the red pine infected with the pinewood nematode fumigated with methyl iodide at 24 hours with 25%（v/v）loading.

Temperature Dose ReplicateResidual gas

Ratio of residual gas * （%） CT productconcentration

（℃） （g/裙） （mg/褄 ± S.D.） 1 hr 24hrs （mg・h/褄 ± S.D.）

40 3 9.9 ± 3.2 60.5 24.8 314 ± 8410 50 3 12.6 ± 2.8 61.2 25.2 391 ± 79

60 3 14.4 ± 0.3 59.0 24.0 451 ± 19

20 2 7.0 ± 1.0 68.0 35.0 206 －

1530 3 11.5 ± 1.3 68.0 38.3 349 ± 340 3 14.9 ± 1.0 73.3 37.3 476 ± 1950 1 16.0 － 63.0 32.0 490 －

2030 3 9.6 ± 2.5 63.7 32.0 276 ± 7240 3 12.9 ± 3.1 66.0 32.3 379 ± 88

10 2 4.5 ± 0.2 77.0 45.0 129 －25 20 4 8.6 ± 2.2 77.5 43.0 245 ± 59

30 3 11.3 ± 2.5 69.7 37.7 310 ± 67

* 100×gas concentration in 1 or 24hrs fumigation（mg/褄）/applied dose（g/裙）.

3March, 2005 SOMA et al. :Mortality and Fumigation Standards for Pine Wood Nematode by Methyl Iodide

Table ２. Mortality data for the pine wood nematode infesting red pine board 1）fumigated with methyl iodide at 24hours with 25%（v/v）loading .

Before fumigation After fumigation

Temperature Dose ReplicateMoisture Weight No of Moisture Weight No of

Survivorcontent 2） of board 3） nematode content 2） of board 3） nematode（℃） （g/裙） （％） （g） /100g （％） （g） /100g （％）

40 3 33.9 256.1 22,400 15.9 383.7 12.5 0.06

1050 3 33.9 256.1 22,400 15.9 464.5 3.9 0.02 60 3 15.9 162.8 10,800 14.9 541.5 0 0

cont. 3 24.9 290.9 16,600 13.0 133.0 10,700 64.5

20 2 28.1 73.6 22,400 20.4 328.0 0.30 0.001 30 3 32.3 224.6 19,200 19.4 460.8 1.52 0.008

15 40 3 32.3 224.6 19,200 19.7 487.6 0 0 50 1 24.9 36.7 14,300 20.2 157.2 0 0

cont. 2 32.3 224.6 19,200 18.7 93.2 19,200 100.0

30 3 33.9 256.1 22,400 14.7 454.5 1.76 0.008 20 40 3 33.9 256.1 22,400 15.3 448.7 0 0

cont. 3 33.9 256.1 22,400 15.9 162.8 10,800 48.2

10 2 38.8 73.9 23,300 24.7 278.9 9.3 0.04

2520 4 33.5 150.4 15,700 17.3 610.7 139.5 0.89 30 3 29.9 123.5 21,100 21.5 510.8 0 0

cont. 3 31.1 160.2 21,500 14.7 133.8 31,000 144.2

1） 15cm thick×15cm wide×30cm long.2） Average moisture content in test wood board.3） Weight of wood samples used for the detection of nematodes.

Fig. １. Progressive gas concentrations for attaining complete mortality of pine wood nema-tode in methyl iodido fumigation with 25% loading of pine wood packing materials.

wood nematode by different temperatures and doses. The remaining gas ratios（gas concentrationat the end of fumigation /applied dose ×100）ranged from 59.0-77.5% for one-hour fumigation , andfrom 24-45% for 24-hour fumigation. A lower remaining gas ratio was confirmed at low fumigationtemperatures. The remaining gas concentrations at the end of 24-hour fumigation were rangedfrom 12 ～26%, lower compared with those for methyl bromide fumigation（Soma et al., 2003）.

10℃・60裼/裙

15℃・40裼/裙

20℃・40裼/裙

25℃・30裼/裙

0 6

40

30

20

10

012 18 24Exposure time（hr.）

Gas concentration（褂/褄）

5 10 15 20 25 30

600

500

400

300

200

100

0

Temperature（ ℃）

Complete mortality

Areas for complete mortality

Areas for incomplete mortalityIncomplete mortality

CT Product（褂・h/褄）

4

Ratios of Residual Gas and CT Products in Gas Absorption TestsFig. 3 and Table 3 show progressive gas concentrations, ratios of residual gas at the end of fumi-

gation and CT products, when the lumber and the boards were fumigated at 50g/裙 with 50% load-ing at different temperatures. Lower gas concentrations were maintained till the end of fumigationat low fumigation temperatures. Ratios of residual gas were reduced in the range of 4-15% becauseof low moisture contents of 20.9-22.3% and a high load factor of 50%（v/v）. Therefore, a higherdose than that in the mortality test would be required for fumigation with a low moisture contentand with a high load factor of wood materials.

RES. BULL. PL. PROT. JAPAN

Fig. 2. Relationship between mortality efficacy and CT products for pine wood nematode infectingpine wood packing materials fumigated with methyl iodide for 24 hours with 25% loading.

No. 41

Mortality of Pine Wood NematodeTable 2 shows the mortality of the pine wood nematode fumigated at different temperatures and

doses for 24 hours with 25% loading. Complete mortality was attained at each of 60g/裙 at 10℃,40g/裙 and 50g/裙 at 15℃, 40g/裙 at 20℃ and 30g/裙 at 25℃, respectively, although some sur-vivors were confirmed at each of 50g/裙 at 10℃, 30g/裙 at 15℃, 30g/裙 at 20℃ and 20g/裙 at 25℃,respectively. These results showed that minimum doses for complete mortality were at each of60g/裙 at 10℃, 40g/裙 at 15 and 20℃ and 30g/裙 at 25 ℃, respectively. Complete mortality was attained at the same dose of 40g/裙 both at 15 and 20℃. The CT productfrom fumigation at 15℃ was higher compared with that at 20℃（Table 1 and Fig. 1）because ofthe lower absorption rate of MI to wood materials at 15℃.

Relationship between Mortality and CT productsFig. 2 shows the relationship between mortality of the pine wood nematode and the CT product

in fumigation at different doses for 24 hours with 25% loading. Although CT products differed fromapplied doses and the absorption rate of MI to wood materials, complete mortality of the pine woodnematode was attained under certain CT products in all off the tests. The CT product showed atendency to be high at low temperatures. The estimated CT products for complete mortality of thepine wood nematode were 450 mg・h/褄 at 10℃, 400 mg・h/褄 at 15℃, 350 mg・h/褄 at 20℃ and300 mg・h/褄 at 25℃, respectively（Table 1 and Table 2）.

10℃

15℃

20℃

25℃

0 6

50

40

30

20

10

012 18 24Exposure time（hr.）

Gas concentration（褂/褄）

5

MI Fumigation Standards for Wood Packing MaterialsTable 4 shows MI fumigation standard for wood materials infected with the pine wood nematode.

Applied doses were used to estimate minimum CT products in Fig. 2（450 mg・h/褄 at 10℃, 400mg・h/褄 at 15℃, 350 mg・h/褄 at 20℃ and 300 mg・h/褄 at 25℃ for complete mortality of thepine wood nematode fumigated for 24-hour fumigation with 25% loading）and CT productsobtained from the test in Table 3（326 mg・h/褄 at 10℃, 410 mg・h/褄 at 15℃, 477 mg・h/褄 at20℃ and 540g・h/褄 at 25℃ fumigated for 24-hour fumigation with a low moisture content and ahigher load factor of 50% of lumber and boards）.

Table 3. Ratios of residual gas and CT products for the red pine wood materials（lumber 1）

and board 2））fumigated with methyl iodide at 50g/裙 for 24 hours with 50% loading.

TemperatureMoisture Ratio of

CT productcontent 3） residual gas 4）（℃） （％） （％） （mg・h/褄）

10 22.3 18.0 32615 21.8 23.6 41020 20.9 27.8 47725 21.5 34.2 540

1） 10cm thick×10cm wide×40cm long.2） 2cm thick×10cm wide×45cm long.3） Average moisture content in test wood materials.4） 100×gas concentration in 24hr fumigation（mg/褄）/applied dose（g/裙）.

Table 4. Methyl iodide fumigation standards for wood packing materials infected with the pine wood nematode.

Temperature Time Load Dose* Minimum gas concentration Minimum factor Warehouse Tarpaulin １ hr 4 hr 24 hrs CT product

（℃） （hr） （%） （g/裙） （g/裙） （mg/褄） （mg/褄） （mg/褄） （mg・h/褄）

10-14.9 24 50 84 112 48 29 16 45015-19.9 24 50 60 80 40 26 14 40020-24.9 24 50 48 64 34 23 12 350

25 or above 24 50 36 48 28 20 10 300

* Gas circulation fan is operated more than 1 hour after dosing.

Fig. 3. Progressive gas concentrations in methyl iodide fumigation at 50g/裙 at different temperatureswith 50% loading of pine wood lumber and board.

March, 2005 SOMA et al. :Mortality and Fumigation Standards for Pine Wood Nematode by Methyl Iodide

6 RES. BULL. PL. PROT. JAPAN No. 41

The applied doses for warehouse fumigation were supplemented with another 20% of the dose（dose equivalent in the amount of absorption to wood materials）and also another 60% of the dose（dose equivalent in the amount of gas leakage）was added to the above mentioned doses for thetarpaulin fumigation. This is the same calculation method as the methyl bromide fumigation stan-dard for the pine wood nematode（Soma et al., 2003）. The Calculation method for applied doses at10℃ is as follows;

CT product obtained from absorption test with 50g/裙 at 10℃: 326 mg・h/褄CT product for a complete mortality at 10℃（Fig. 2）: 450 mg・h/褄Dose required for complete mortality at 10℃：50 g/裙×450/326 = 69.0 g/裙Applied dose in the warehouse fumigation: 69.0×1.2 = 82.8 g/裙Applied dose in the tarpaulin fumigation: 69.0×1.6 = 110.4 g/裙

The following doses of MI under conditions of 24-hour fumigation with 50% loading of wood pack-ing materials were determined for the warehouse and tarpaulin fumigation, namely, at each of 84g/裙（warehouse）and 112g/裙（tarpaulin）at 10 ℃, 60g/裙（warehouse）and 80g/裙（tarpaulin）at 15℃，48 g/裙（warehouse）and 64g/裙（tarpaulin）at 20℃ and 36g/裙（warehouse）and 48g/裙（tarpaulin）at 25℃, respectively as shown in Table 4.Minimum gas concentrations during fumigation were estimated by both data from progressive gasconcentrations in the test for a complete mortality by different temperatures（Fig. 1）and from theCT product required for complete mortality. In particular, the minimum gas concentration at theend of 24-hour fumigation was indispensable concentrations for attaining adequate efficacy of themortality for the pine wood nematode. The minimum gas concentration in 1 and 4 hours after dos-ing are indicators for the accurate fumigation. If the gas concentrations in 1 and 4 hours are lowerthan the minimum gas concentration, the fumigation would fail because of a shortage of gas con-centration at the end of fumigation. In practical fumigation, a gas-tight fumigation chamber shouldbe used for fumigation and care should be taken against gas leakage from tarpaulin. If minimumgas concentrations in 1 and 4 hours were insufficient suitable action with use of an additional doseor extension of the fumigation time should be taken for fumigation.

References Cited

KAWAKAMI, F., Y.SOMA, H.KOMATSU and Y.MATSUMOTO（2004）Effects of Some Fumigants on Pine Wood

Nematode, Bursaphelenchus xylophilus Infecting Wooden Packages. 4. Mortality and CT product in

Methyl Bromide Fumigation with High Loading of Wood Packing Materials. Res.Bull.Pl.Prot.Japan 40:7-

12.

SOMA, Y., H. NAITO, T. MISUMI, M. MIZOBUCHI, Y. TSUCHIYA, I.MATSUOKA, F.KAWAKAMI and K.HIRATA（2001）

Effects of Some Fumigants on Pine Wood Nematode, Bursaphelenchus xylophilus Infecting Wooden

Packages 1. Susceptibility of Pine Wood Nematode to Methyl Bromide, Sulfuryl Fluoride and Methyl

Isothiocyanate. Res.Bull.Pl.Prot.Japan 37:19-26.

SOMA, Y., H. NAITO, T. MISUMI, M. MIZOBUCHI, Y. TSUCHIYA, I. MATSUOKA, F.KAWAKAMI and K.HIRATA（2002）

Effects of Some Fumigants on Pine Wood Nematode, Bursaphelenchus xylophilus Infecting Wooden Packages

2. Mortality of Pine Wood Nematode to Methyl Bromide Tent Fumigation. Res.Bull.Pl.Prot.Japan 38:13-19.

SOMA, Y., M.GOTO, N.OGAWA, F.KAWAKAMI, K.HIRATA, H.KOMATSU and Y.MATSUMOTO（2003）Effects of Some

Fumigants on Pine Wood Nematode, Bursaphelenchus xylophilus Infecting Wooden Packages 3. Mortality

of Fumigation Standards for Pine Wood Nematode to Methyl Bromide. Res.Bull.Pl.Prot.Japan 39:7-14.

7

和　文　摘　要

マツノザイセンチュウBursaphelenchus xylophilus が寄生した

梱包材のくん蒸剤による消毒試験

５．ヨウ化メチルによる温度別殺線虫効果とくん蒸基準の検討

相馬幸博・後藤睦郎・小川　昇・内藤浩光・平田賢司

横浜植物防疫所調査研究部

マツノザイセンチュウが100g当たり１万頭以上寄生し

たアカマツの梱包材（角材：15cm×15cm×30cm）を用

い、収容率25％、24時間の条件で薬量別、温度別にヨウ

化メチルくん蒸を行い、殺虫効果とＣＴ値を調査した。

その結果、10℃では60g/裙、15℃及び20℃では40g/裙、

25℃では30g/裙の薬量でマツノザイセンチュウは完全殺

虫された。試験で得られたＣＴ値（mg・h/褄）により、

完全殺虫に必要な最低ＣＴ値を温度別に推定した結果、

10℃では450mg・h/褄、15℃では400mg・h/褄、20℃で

は350mg・h/褄、25℃では300mg・h/褄であった。また、

乾燥した梱包材を収容率50％で24時間くん蒸したときの

ＣＴ値に基づき、倉庫及び天幕くん蒸の必要薬量を温度

別に計算した結果、10℃が84g/裙（倉庫）及び112g/裙

（天幕）、15℃が60g/裙（倉庫）及び80g/裙（天幕）、

20℃が48g/裙（倉庫）及び64g/裙（天幕）、25℃が36g/

裙（倉庫）及び48g/裙（天幕）であった。

SOMA et al. :Mortality and Fumigation Standards for Pine Wood Nematode by Methyl IodideMarch, 2005