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2008 Plant Management Network.
Accepted for publication 14 January 2008. Published 17 March 2008.


Efficacy of Chemical and Biological Agents to Suppress Fusarium and Pythium Damping-Off of Container-Grown Douglas-fir Seedlings


Robert G. Linderman, Research Plant Pathologist, and E. Anne Davis, Biological Laboratory Technician, USDA-ARS Horticultural Crops Research Laboratory, Corvallis, OR 97330; and Charles J. Masters, Technology Implementation, Weyerhaeuser Company, Centralia, WA 98531


Corresponding author: R. G. Linderman. lindermr@science.oregonstate.edu


Linderman, R. G., Davis, E. A., and Masters, C. J. 2006. Efficacy of chemical and biological agents to suppress Fusarium and Pythium damping-off of container-grown Douglas-fir seedlings. Online. Plant Health Progress doi:10.1094/PHP-2008-0317-02-RS.


Abstract

Douglas-fir seedlings are susceptible to Fusarium or Pythium damping-off that currently is controlled by pre-plant soil fumigation in bareroot nurseries and steam pasteurization or chemical drenches of soilless media in container nurseries. However, because few chemical or biological agents are registered for use on conifer seedlings, we tested several on greenhouse-grown seedlings and found that over-seed applications of Clearys 3336, Strike, Compass, Compass + Strike, Cygnus, Endura, Medallion, Medallion + Strike, Thiram, and Enzone effectively suppressed pre-emergence damping-off by Fusarium oxysporum, but only Clearys 3336WP and Medallion + Strike also reduced post-emergence damping-off. Compass, Medallion, and Thiram reduced post-emergence damping-off, but not to a statistically significant level. Pre-emergence damping-off by Pythium irregulare was reduced only by Ranman, but post-emergence damping-off was reduced by Thiram, Hurricane, Ranman, and Subdue MAXX. Over-seed drenches of biological control agents Companion, Kodiak, Subtilex, Taegro, Primastop, SoilGard, Actinovate, Mycostop, RootShield, and Green-Releaf were ineffective in suppressing either Fusarium or Pythium diseases, and combining several agents with chemicals did not improve efficacy. These results provide data in support of registration of some of the effective chemicals, but no biological control agents, for the control of conifer seedling damping-off.


Introduction

Seedlings of Douglas-fir [Pseudotsuga menziesii (Mirb.)] and other conifer species are susceptible to damping-off and root rot caused by species of Fusarium or Pythium (2). These diseases can occur on seedlings grown in either containers or in-ground beds of bareroot nurseries, and can be manifested as pre-emergence or post-emergence damping-off, or as stunted seedlings that die due to root rot. Control of these diseases in bareroot nurseries has been primarily by pre-plant fumigation, although Fusarium spp. may also be seedborne (3) and thus would be unaffected by soil fumigation. Seed treatments to remove fusaria on seed (1) have been employed by some nurseries using running water or treating seed with chemicals such as sodium hypochlorite (bleach), hydrogen peroxide, or Thiram. Seed treatment with hydrogen peroxide (4) alone effectively removes surface seedborne fusaria, but following that treatment with a bacterial antagonist failed to provide protection against Fusarium infection and disease in pathogen-infested medium. However, application of other candidate biocontrol agents could prove this practice useful. Hydrogen peroxide can also cause problems with reduced seed germination and/or phytotoxicity to young germinants.

Recently, some new chemicals and biological control agents (BCAs) have been developed commercially on other crops that could be used to reduce losses from Fusarium or Pythium infections on conifer seedlings. Several of these agents were tested comparatively in this study as over-seed drench applications.


Preparation of Inoculum and Inoculation Procedure

Fungal inoculum was prepared for all studies using vermiculite infested with Fusarium oxysporum Schlect. or Pythium irregulare Buisman. Both fungi were shown to be pathogenic on Douglas-fir in preliminary tests. F. oxysporum was first grown on acidified potato dextrose agar (25 ml/liter lactic acid), and P. irregulare was grown on dilute V8 Juice agar (50 ml/liter clarified V8 juice) in Petri dishes for 14 days at 20C. Inoculum was prepared by adding clarified V8 broth (7) to dry vermiculite (70% v:v) contained in a 52.5  20  11.88-cm autoclavable polyethylene bag (12468.75 cm), with a contaminant barrier filter patch (Fungi Perfecti, Olympia, WA). Bags were then autoclaved (120C, 15 psi, 60 min) twice with an overnight cooling period between treatments. Mycelium on agar from two Petri dishes of a desired isolate were cut into approximate 1.5-cm squares and transferred aseptically from 14-day-old culture plates to each autoclaved bag. These were stored in a dark incubator at 20C for 2 months, with periodic redistribution of contents. Prior to incorporation of vermiculite inoculum into the seedling potting mix, the inoculum was placed in cheesecloth and washed with water to remove excess nutrients and culture metabolites, air dried for 48 h to a moisture level suitable for easy mixing, and tested for viability by plating on selective media.

The Douglas-fir soilless seedling mix was a steam-pasteurized, pathogen-free proprietary blend of peatmoss, perlite, and starter fertilizers, supplied by The Weyerhaeuser Company (Rochester, WA). Fusarium and Pythium vermiculite inocula were incorporated into the seedling mix at an average rate of 10% by volume. Douglas-fir seedlings were grown in plastic trays designed specifically for seed germination and seedling growth in Weyerhaeuser nurseries. Two days before treatment, a total volume of 2.95 dm of each flat, containing 64 planting cells, was filled with pathogen-infested soilless mix and moistened by misting until gravitational drainage was apparent. One cold-stratified, untreated seed was sown at 0.32-cm depth in each cell. Chemical or biological products were manually applied as drenches just after seeding, following product label or product specialist's recommendations. Specific treatments and replications are designated within each study. All studies were arranged on greenhouse benches in a randomized block design, with Fusarium and Pythium trays maintained on separate benches to prevent cross-contamination.


 

Fig. 1. Greenhouse-grown Douglas-fir seedlings in plug trays inoculated (right) or not with Fusarium oxysporum, showing pre-emergence damping-off reaction.

 

 

Fig. 2. Greenhouse-grown Douglas-fir seedlings, one in center showing post-emergence mortality from infection by Fusarium oxysporum.

 

Greenhouse temperatures were 23/18C day/night, and after seedlings had germinated lighting was supplemented by high-pressure multi-vapor lamps for 14-h daylengths during November to April. Water was applied as needed, usually thrice-weekly, using a low-pressure sprinkler nozzle. Any control flats without pathogens were removed from the bench set-up and watered apart from the pathogen-infested flats to avoid cross contamination.


Disease Evaluation and Statistical Analysis

Germination was counted three weeks after seeding, and survival was counted weekly for the next six weeks. Then ten seedlings were removed from each treatment replication to assess pathogen recovery from roots. Roots were washed clean of growth medium debris, severed from shoots, and cut into approximate 1-cm segments. Segments were surface-disinfested in 0.03% sodium hypochlorite solution for 3.0 min, followed by immersion in sterile distilled water for 0.5 min. Ten randomly chosen segments were retrieved with forceps, blotted dry on paper towels, and plated on PARP medium (5) for Pythium isolation, or Komada's medium (6) for Fusarium isolation. Plates were incubated in the dark for 5 to 7 days, after which infected root pieces were counted. The percentage of infected segments was calculated separately for each replicate sample.

At the end of six weeks, ten more seedlings were removed for biomass determination. Seedlings were gently washed free of growth medium debris, roots severed from shoots, and roots and shoots dried at 70C for 48 h and weighed.

Data were analyzed separately for each experiment. Arcsine-transformed seedling survival data and log-transformed biomass data were analyzed by analysis of variance using Systat 8.0 (SPSS Inc., Evanston, IL). Where appropriate, Fishers protected least significance test at P ≤ 0.05 (FPLSD0.05) were used to separate treatment means. Untransformed data are presented in all tables.


Chemical and Biological Control Agents, and Method of Application

The chemicals and BCAs we evaluated in 2002-2003, and rates used are shown in Tables 1 and 2, respectively. All were applied as over-seed drenches immediately after sowing seeds in flats, except for Thiram, which was applied as a seed-coat treatment four hours prior to sowing. Reapplication of chemicals followed label or product specialist recommendations, usually at two-week or four-week intervals. All BCAs were reapplied at two-week intervals. Non-chemical control treatments, with and without pathogens, were also included.


Table 1. Chemical products evaluated to determine efficacy in controlling Fusarium or Pythium damping-off of greenhouse-grown Douglas-fir seedlings.x

Treatment
product
Product description Rate of
product
y
3336WP 50% thiophanate-methyl

Cleary Chemical Corp, Dayton, NJ

900 g
Banrot 40%WP 15% etridiozole, 25% thiophanate methyl

Scott-Sierra Crop Protection, Marysville, OH

600 g
BAS 516-04 38WG Proprietary information

BASF Corp., Research Park Triangle, NC

1900 g
Biophos (Lexx-a-phos) 22.7% di-potassium phosphate,

22.4% di-potassium phosphonate

Foliar Nutrients Inc., Cairo, GA

10 l
Compass 50% trifloxystrobin

Bayer Environmental Science, Montvale, NJ

75 g
Cygnus 50WG 50% kresoxim-methyl

BASF Corp., Research Park Triangle, NC

2.4 l
Endura Proprietary information

BASF Corp., Research Park Triangle, NC

600 g
Enzone 31.5% sodium tetrathiocarbonate

Entek Corp., Elkridge, MD

3.7 l
Heritage 50% azoxystrobin

Syngenta Crop Protection, Greensboro, NC

100 l
Hurricane 32% fludioxonil, 16% mefenoxam

Syngenta Crop Protection, Greensboro, NC

300 g
Insignia 20% pyraclostrobin

BASF Corp., Research Park Triangle, NC

2400 g
Medallion 50% fludioxonil

Syngenta Crop Protection, Greensboro, NC

0.2 l
Ranman 40% cyazofamid

ISK Biosciences, Mentor, OH

0.5 l
Strike 25WDG 25% triadimefon

Olympic Horticultural Products, Mainland, PA

300 g
Subdue MAXX 22% mefanoxam

Syngenta Crop Protection, Greensboro, NC

0.16 l
Thiram (42-S) 42% tetramethylthiuram disulfide

Gustafson LLC, Plano TX

0.024 g

 x All products applied as drenches directly after seed-sowing, except Thiram, applied as a seed-coating four hours before sowing. All products applied according to label or product specialist-recommended rates.

 y Rate of product per ml of solution except for Thiram seed coat (= per gm of seed)


Table 2. Biological products evaluated to determine efficacy in controlling Fusarium or Pythium damping-off of greenhouse-grown Douglas-fir seedlings.x

Treatment
product
Product description Rate of producty
Actinovate 1% Streptomyces lydicus WYEC-108

Natural Industries Inc., Houston, TX

450 g
Companion 0.03% Bacillus subtilis GB-03

Growth Products Ltd., White Plains, NY

1.25 l
Kodiak 1.37% Bacillus subtilis GB-03

Gustafson LLC, Plano TX

1.25 l
Green-Releaf 0.14% Bacillis licheniformis SB-3086

Novozymes Biologicals, Salem, VA

2.8 l
MycoStop 30% Streptomyces grisiovirides K-61

Verdera oy, Fin-02201, Espoo, Finland

300 g
PrimaStop 37% Gliocladium catenulatum J-1446

Verdera oy, Fin-02201, Espoo, Finland

5000 g
RootShield Trichoderma harzianum T-22 (KRL-AG2)

BioWorks Inc., Geneva, NY

375 g
Soilgard 12G 12% Gliocladium virens G-L21

Certis USA LLC, Columbia, MD

2400 g
Subtilex 2.75% Bacillus subtilis MBI-600

Becker Underwood Inc., Ames, IA

600 g
Taegro 24.5% Bacillus subtilis FZB-24

Taensa Inc., Fairfield, CT

200 g

 x All products applied as drenches directly after seed-sowing, according to label or product specialist-recommended rates.

 y Rate of product per ml of solution.


Another experiment in 2004, combining selected chemical products and BCAs, was conducted in late 2004. Three commercial BCAs previously tested Actinovate, Taegro, and Subtilex were combined into one treatment (BA1). Chemical products included Endura, BAS 516, Cygnus, Cleary 3336, Heritage (each reapplied every two weeks), Insignia, Hurricane, Ranman (each reapplied every four weeks), and Subdue MAXX (no reapplication). Each of these was tested with and without an application of BA1. The BA1 treatment was prepared by mixing Actinovate, Taegro, and Subtilex into distilled water at label rates, and allowing the mixture to stand 12 h before use.

Since the application of Hurricane had shown some signs of phytotoxicity when both the chemical and pathogen were present, we did another experiment comparing treatments with the chemical alone with the chemical plus Pythium. In both cases, Hurricane was applied at 0, 1, 2, and 4 the recommended label rate, both over the seed at planting or after 4 weeks of seedling growth.


Efficacy of Chemical and Biological Treatments

The results of a series of experiments using chemical and biological agents to control Fusarium or Pythium damping-off are shown in Tables 3, 4, and 5. In 2002 (Table 3), both pre- and post-emergent damping-off by Fusarium were significantly reduced by chemical applications; seedling total biomass after 10 weeks was not significantly improved. Post-emergence Pythium damping-off was effectively controlled by Hurricane, Thiram, Ranman, and Subdue MAXX at 6 weeks. The Pythium-inoculated seedlings were not significantly smaller than non-treated, non-inoculated controls, although the pathogen was recoverable. F. oxysporum was recovered from 100% of the roots of all inoculated treatments at harvest time, while P. irregulare recovery was reduced to near-zero by Hurricane, Ranman, and Subdue MAXX.


Table 3. Effects of chemical application on survival and biomass of Douglas-fir seedlings grown in Fusarium- or Pythium-infested soilless mix (2002).

Treatment/
product
Fusarium Pythium
Total

dry wt
(mg)x

Survival (%) Total

dry wt
(mg)

Survival (%)
3 wks 6 wks 3 wks 6 wks
None minus pathogen 107 ay   89 ab   86 a  108 a    93 a   93 a
None plus pathogen   53 b   48 c   18 g   89 ab    88 ab   74 d
3336WP   94 ab   91 ab   86 a    na -    na -    na -
Strike   76 ab   81 b   38 f    na -    na -    na -
Compass   80 ab   89 ab   77 bc    na -    na -    na -
Compass + Strike   82 ab   88 ab   60 d    na -    na -    na -
Cygnus   94 ab   87 ab   56 d    na -    na -    na -
Endura   87 ab   88 ab   56 d    na -    na -    na -
Medallion   90 ab   92 ab   72 c  115 a    79 bc   79 cd
Medallion + Strike   80 ab   95 a   80 ab    na -    na -    na
Thiram   63 ab   82 b   78 b   72 abc    74 c   85 abc
Enzone   59 b   88 ab   46 e   92 ab    84 bc   79 cd
Heritage    naz -    na -    na -   31 c    32 d   33 e
Hurricane    na -    na -    na -   60 bc    89 ab   91 ab
Ranman    na -    na -    na -  108 a    93 a   84 bc
Subdue MAXX    na -    na -    na -   94 ab    88 ab   86 abc

 x Biomass data given as average mg per plant seedling survival as percent.

 y Mean separation within a column using FPLSD0.05. Treatments sharing the same letters are not significantly different. Each value is the average of four replicate blocks with 10 seedlings in each block.

 z na = product not applied; em-dash indicates inadequate quantity survived for biomass determination no analyses.


Table 4. Effects of biological and chemical agents on survival and biomass of Douglas-fir seedlings grown in Fusarium- or Pythium-infested soilless mix (2003).

Treatment/
product
Fusarium Pythium
Total

dry wt
(mg)x

Survival (%) Total

dry wt
(mg)

Survival (%)
3 wks 6 wks 3 wks 6 wks
None minus pathogen 124 ay   89 a  91 a  129 ab  93 a   90 a
None plus pathogen 103 ab   65 b-e  61 cde  105 ab  81 abc   77 ab
Companion   79 a-d   63 b-e  54 def  110 ab  75 bcd   72 bcd
Kodiak   69 bcd   61 b-e  49 ef  119 ab  80 bc   79 ab
Subtilex   86 a-d   59 cde  64 cde  119 ab  78 bc   72 bcd
Taegro   68 bcd   55 de  50 def  110 ab  81 abc   77 ab
Primastop   90 abc   59 cde  57 def  130 a  70 cd   68 cde
SoilGard   84 a-d   73 a-d  67 bc   92a bc  51 e   48 f
Actinovate   65 bcd   50 e  43 f   85 abc  71 cd   63 cde
Mycostop   95 ab   68 b-e  65 bc  104 ab  71 cd   63 cde
RootShield   75 a-d   66 b-e  60 c-f  109 ab  79 cd   74 bc
Green-Releaf   48 cd   21 f  26 g   50 cd  36 f   34 g
3336WP   97 ab   60 ab  78 ab   na -   na -   na -
Insignia   41 d   49 e  47 ef   36 d  36 g   33 g
Endura 122 a   63 b-e  63 cde   na -   na -   na -
Cygnus   85 a-d   75 abc  75 ab   na -   na -   na -
Biophos   94 ab   63 b-e  63 cde  127 ab  85a b   82 ab
Banrot 100 ab   66 b-e  63 cde  104 ab  80 bc   77 ab
Hurricane   naz-   na -   na -   84 bc  63 de   59 de
Ranman   na -   na -   na -  106 ab  75 bcd   66 cde
Subdue MAXX   na -   na -   na -   90 abc  63 de   58 ef

 x Biomass data given as average mg per plant seedling survival as percent.

 y Mean separation within a column using FPLSD0.05. Treatments sharing the same letters are not significantly different. Each value is the average of four replicate blocks with 10 seedlings in each block.

 z na = product not applied; no analyses.


Table 5. Effects of chemical agents applied alone or in combination with a bacterial antagonist mixture (BA1) on survival and biomass of Douglas-fir seedlings grown in Fusarium- or Pythium-infested soilless mix (2004).

Treatment/
product
Fusarium Pythium
Total
dry wt

(mg)w
Survival
(%)
Total
dry wt

(mg)
Survival
(%)
3 wks 6 wks 3 wks 6 wks
Chemical
only
None minus pathogen   90 ax 88 a 87 a 66 a 86 a 78 a
None plus pathogen 88 a 72 c 71 c 65 a 54 c 43 c
3336WP 90 a  83 ab 79 b na
BAS 516-04F y 53 d 47 d na
Endura 82 a 81 b 79 b na
Insignia  naz na na 46 d 38 d
Hurricane na na na 56 a 53 c 60 b
Ranman na na na 74 a 54 c 60 b
Subdue MAXX na na na 56 a 60 b 60 b
Chemical
plus BA1
None minus pathogen 81 A 92 A 88 A 70 A 78 A 79 A
None plus pathogen 65 A 73 B 69 C 65 A 49 C 39 C
3336WP 89 A 83 E 81 B na na na
BAS 516-04F 48 C 28 D na na na
Endura 75 A 79 B 75 I   na na na
Insignia na na na 36 C 28 D
Hurricane na na na 63 A 41 B 50 B
Ranman na na na 70 A 40 B 52 B
Subdue MAXX na na na 65 A 54 B 51 B

 w Biomass given as average mg per plant; seedling survival as percent.

 x Mean separation within a column using FPLSD0.05. Treatments sharing the same letters are not significantly different. Each value is the average of four replicate blocks with 10 seedlings in each block.

 y "—" indicates too few seedlings survived for biomass determination; no analyses.

 z na = product not applied; no analyses.


In 2003 (Table 4), Fusarium significantly reduced survival of non-treated seedlings, although total biomass was not reduced. Pre-emergent damping off was not effectively controlled by chemical application, but post-emergent attack was reduced by Cleary's 3336WP and Cygnus, while being increased by Actinovate and Green-Releaf. Total seedling biomass was significantly reduced (FPLSD ≤ 0.05) by Green-Releaf and Insignia. Inoculation with P. irregulare did not effectively reduce seedling survival, for which we have no explanation, since the pathogen grew out of all inoculum pieces prior to the test. Within this constraint, however, we found a reduction in seedling survival with several chemical treatments. Again, total biomass was significantly reduced by Green-Releaf and Insignia. F. oxysporum was recovered from 95 to 100% of the roots of all inoculated treatments at harvest time, and P. irregulare was recovered from 13 to 100% of all roots, the lowest being from the Ranman treatment.

Both Fusarium and Pythium induced significant damping-off in our 2004 study, with or without the presence of BCAs (Table 5). Without BCAs, pre- and post-emergent Fusarium damping-off was decreased by Cleary 3336WP, whereas Endura was effective only at pre-emergence. BAS 516 significantly (FPLSD ≤ 0.05) worsened survival, which may have been a phytotoxic effect. Pythium damping-off was effectively reduced by Subdue MAXX. Adding BCAs to chemical and non-chemical treatments had no significant effect (P = 0.05) on reducing damping-off effects for either pathogen, nor on seedling total biomass. In the presence of Fusarium, Cleary 3336WP again improved seedling survival, while BAS 516 worsened it. In the presence of Pythium, Hurricane, Ranman, and Subdue MAXX improved survival. Recovery of the pathogens at harvest was not affected by BCAs, which ranged from 97 to 100% for F. oxysporum and 60 to 100% for P. irregulare.

Hurricane by itself was not phytotoxic in terms of germination and final stand (Table 6), but there was a significant reduction (FPLSD ≤ 0.05) in total growth at harvest at the 4 rate when the chemical was applied over the seed. No toxicity was detected at any rate when it was applied as a drench over 4-week-old seedlings. Main effects of Hurricane rate, time of application, and Pythium inoculation were not significant (P ≤ 0.05) for germination or survival of seedlings. However, all three factors had very highly signficant effects (P ≤ 0.001) on growth at harvest, as did their interactions, except for the insignificance (P ≤ 0.05) of application time  Pythium inoculation. In the presence of Pythium, however, there was significant (FPLSD ≤ 0.05) growth reduction with Hurricane at 2 and 4 rates with seed application only. These data would suggest that some interaction between Hurricane and Pythium occurred, but the nature of that interaction was not explored further.


Table 6. Effects of Hurricane on survival and biomass of Douglas-fir seedlings grown in Pythium-infested soilless mix.

Pythium

treatment

Hurricane

rate

Seed application Seedling application
Total

dry wt
(mg)x

Survival (%) Total

dry wt
(mg)

Survival (%)
3 wks 6 wks 3 wks 6 wks
None None 121ay 84a 87a 118b 83a 86a
1x 112a 77a 77a 126ab 86a 86a
2x 116a 84a 86a 132ab 80a 83a
4x 88b 87a 84a 129a 86a 86a
Plus None 105A 87A 87A 107B 88A 90A
1x 100A 78A 81A 122A 78A 79A
2x 81B 88A 88A 106B 79A 80A
4x 87B 82A 84A 104B 81A 81A

 x Biomass given as average mg per plant; seedling survival as percent.

 y Mean separation within a column using FPLSD0.05. Treatments sharing the same letters are not significantly different. Each value is the average of four replicate blocks with 10 seedlings in each block.


Discussion

A number of chemical agents significantly reduced pre-emergence damping-off (evaluated at 3 weeks after germination) by both pathogens, but were sometimes less effective in reducing post-emergence damping off (evaluated at 6 weeks after germination). The results of over-seed applications of BCAs (Table 4) indicated that none of the agents alone was effective in reducing either Fusarium or Pythium damping-off. Green-Releaf and Insignia significantly reduced germination and survival as well as biomass of resulting seedlings. Combining chemical treatments with selected BCAs (BA1) did not improve efficacy of the chemical treatments (Table 5). We presume that the lack of efficacy from the BCAs was due to low or slow metabolic activity by the agents in relation to the time and extent of pathogen activity. In results from other unpublished experiments, we attempted to stimulate bacterial growth and activity by adding alfalfa meal extract with the agents, but the additional organic matter enhanced disease by both F. oxysporum and P. irregulare and not the activity of the BCAs. Perhaps soaking the seed in the BCAs would have improved their efficacy.


Acknowledgments and Disclaimers

We acknowledge the excellent assistance from Bryan Beck, Amber Wierck, Harvey McDaniel, and Kenneth Rolfe in this project. Mention of a trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product by the U. S. Department of Agriculture and does not imply its approval to the exclusion of other products or vendors that also may be suitable.


Literature Cited

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4. Hoefnagels, M. H., and Linderman, R. G. 1999. Biological suppression of seedborne Fusarium spp. during cold stratification of Douglas fir seeds. Plant Dis. 83:845-852.

5. Kannwischer, M. E., and Mitchell, D. J. 1978. The influence of a fungicide on the epidemiology of black shank of tobacco. Phytopathology 68:1760-1765.

6. Komada, H. 1975. Development of a selective medium for quantitative isolation of Fusarium oxysporum from natural soils. Rev. Plant Prot. Res. 8:114125.

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