Pao-Jen Ann Taiwan Agricultural Research Institute, Taichung, Taiwan

Tun-Tschu Chang Taiwan Forestry Research Institute, Taipei, Taiwan

Wen-Hsiung Ko University of Hawaii at Manoa, Hilo, HI Brown Root Rot of Fruit and Ornamental Trees in Taiwan

In 1985, the third author (W. H. Ko) no- History and Occurrence ceous plants are also susceptible to the ticed unusually high mortality of some of the Disease Worldwide pathogen. P. noxius is widespread among fruit trees in residential areas in southern tropical countries in Southeast Asia, Af- The causing brown root disease Taiwan. Tree death appeared to be very rica, Oceania, Central America, and the of trees was first described in Singapore by sudden, because all the leaves had turned Caribbean (25). It has also been reported Corner in 1932 as Fomes noxius (18) and brown but had remained attached to the from the tropical Hainan Island of China reclassified by Cunningham in 1965 as branches (Fig. 1). In 1987, numerous dying (29). In Japan, the pathogen was found Phellinus noxius (19). Corner speculated longan trees (Dimocarpus longan) were only on the subtropical island of Okinawa that the fungus was the cause of brown found in the mountain areas of central and (1). In Taiwan, it has been found in both root rot of rubber trees and tea bushes. southern Taiwan. Trees in the early stages tropical and subtropical districts (8,17). However, attempts to demonstrate patho- of decline exhibited a brown discoloration genicity of this fungus were not successful of the wood on large roots (Fig. 2). A fast- The Pathogen until the realization that it requires a food growing, basidiomycete-like fungus was P. noxius is a fast-growing organism. base for successful infection of the host. subsequently isolated from diseased roots, The linear growth rate can be 35 mm/day Bolland (11) inoculated hoop pine and inoculation studies verified its patho- on potato dextrose agar (PDA) at 30°C (Araucaria cunninghamii) by inserting a genicity. However, it was not possible to (4,7). The fungus produces a brown colony severed root into a jar containing 250 g of identify the pathogen at the time because on PDA with irregular dark brown lines or enriched sawdust medium colonized by P. fruiting bodies were not initially found on patches permeating the culture (Fig. 5). noxius. The fungus killed the inoculated diseased trees in the field or in laboratory Arthrospores (Fig. 6) and trichocysts (Fig. root and began to girdle the tree within 6 cultures, nor were clamp connections ob- 7), but not clamp connections, are com- months. served on hyphae. monly produced in culture. When grown P. noxius has a wide host range; it has In 1990, Ko found a young, thin, flat, on sawdust medium, P. noxius produces been reported on more than 200 plant spe- brown basidiocarp with a white margin on thin, hard, uneven basidiocarps (Fig. 4) cies representing 59 families. Although an exposed root of a diseased longan tree. similar to those found in nature. They are most hosts are woody plants, some herba- He then realized that what looked like dirty initially yellowish-brown with a white bark on the basal stems of some declining margin and later become brown and then trees was in fact remnants of decomposed dark gray. In addition to basidiospores, fruiting bodies of the pathogen (Fig. 3) and that fungal structures previously thought to be mycelial mats on sawdust medium were actually fruiting bodies (Fig. 4). Subse- quently, the fungus was identified as Phel- linus noxius (Corner) G. H. Cunn. Soon after the report of brown root rot causing serious decline in longan (2), the P. noxius pathogen was found to be wide- spread and destructive on a number of tree species throughout Taiwan. Due to the seriousness of the problem, the Taiwan government created a Phellinus noxius Brown Root Rot Diagnosis and Control Information Center in 2000 to address public concern about the disease.

Dr. Ko’s address is: Department of Plant and Environmental Protection Sciences, Beaumont Agricultural Research Center, University of Ha- waii at Manoa, Hilo, HI 96720; E-mail: [email protected] Fig. 1. Quick decline of a 6-year-old lon- gan tree (Dimocarpus longan) resulting Fig. 2. A large longan root with brown Publication no. D-2002-0524-01F from brown root rot caused by Phellinus discoloration caused by Phellinus nox- © 2002 The American Phytopathological Society noxius. ius.

820 Plant Disease / Vol. 86 No. 8 there are scant hymenial setae and narrow rot on roots. The 18 hosts (Table 1) he ity tests have now been accomplished with setal hyphae inside the basidiocarp, which found were located in northern, central, this method for most of the hosts of P. distinguish P. noxius from the closely re- and southern Taiwan. His report remained noxius reported from Taiwan (4,7,9,13). lated species of Phellinus lamaensis (Fo- essentially unnoticed until 1991, when the In Taiwan, P. noxius causes brown root mes lamaensis) (25). fungus became a serious threat to the culti- rot on a number of popular tropical fruit P. noxius is a high-temperature organism vation of certain fruit trees (2–4). Among crops such as longan, litchi, carambola, with optimal growth near 30°C and none at the approximately 200 plant species listed loquat, avocado, and sugar apple (Table 1). 8°C. This may explain the geographic re- as hosts of P. noxius in the world, about Some persimmon, peach, pear, plum, and striction of this pathogen to tropical and half of them were reported for the first grape cultivars were also attacked by the subtropical regions. The fungus prefers time from Taiwan (Table 1). Most of the pathogen in subtropical areas. The disease acidic conditions and is capable of growth hosts found in Taiwan are woody fruit and causes considerable losses to growers each at a pH as low as 3.5. Growth is com- ornamental trees. Only seven species are year. Due to its wide host range, most of pletely inhibited at a pH of 7.5 (7). herbaceous plants. the tree species used in ornamental land- Not all hosts listed in Table 1 have been scape plantings are susceptible to brown Hosts and Geographic proven experimentally to be susceptible to root rot. P. noxius causes decline and death Distribution in Taiwan P. noxius. Prior to 1992, most species of of ornamental trees planted on campuses, Brown root rot caused by P. noxius was plants were reported as hosts of P. noxius sightseeing places, and parks, and around reported in Taiwan by Sawada as early as without completion of Koch’s postulates. private and public buildings (Figs. 8 and 9). 1928 (26). The fungus was identified as We employed a simple inoculation tech- Fomes lamaensis, which he later consid- nique developed by Ko et al. (22) to ered to be a synonym of Fomes noxius demonstrate pathogenicity. The method (27). Initially, Sawada did not find the consisted of culturing P. noxius in a wheat– fruiting bodies of P. noxius, so the identifi- oat medium and wrapping approximately 5 cation was based on the symptom of brown g of the colonized medium with a sheet of clear plastic around the lightly scraped stem or taproot (4). Successful pathogenic-

Fig. 7. Trichocysts of Phellinus noxius produced on potato dextrose agar.

Fig. 3. Basal stem of a longan tree (Di- mocarpus longan) with remnants of old decomposed fruiting bodies of Phel- Fig. 5. Colony of Phellinus noxius on linus noxius. potato dextrose agar with irregular dark brown lines or patches permeating the culture.

Fig. 8. A 5-year-old golden shower tree (Cassia fistula) killed by Phellinus nox- ius in a park.

Fig. 9. A camphor tree (Cinnamomum Fig. 4. A thin, flat basidiocarp of Phellinus Fig. 6. Arthrospores of Phellinus noxius camphor) killed by Phellinus noxius in noxius produced on sawdust medium. produced on potato dextrose agar. front of a residential house.

Plant Disease / August 2002 821 Brown root rot has been found in every Table 1. List of host records of Phellinus noxius in Taiwan county on the island of Taiwan (Fig. 10) but not in mountainous areas above 1,000- Year first Reported reported (or found) m elevation, even though there are numer- Scientific name (common name) (or found) as new disease Citation ous susceptible hosts in those areas (17). Apparently the cold winter in these areas is Fruit trees a detrimental to disease development (7). 1. Annona montana (mountain soursop) 1996 + 6,8 Annona squamosa P. noxius 2. (custard apple) 1991 + 3,7,23 The distribution of in Taiwan 3. Annona squamosa × A. cherimola (atimoya) (1994) + Ub appears to be limited to areas with human 4. Artocarpus heterophyllus (jack fruit) 1998 + 17 activity. Brown root rot has never been 5. Averrhoa carambola (carambola) 1991 + 3,7 found in undisturbed natural forests, sug- 6. Dimocarpus longan (longan) 1928 + 4,26 gesting that the pathogen is not indigenous 7. Diospyros kaki (persimmon) 1994 + 5,7 to Taiwan. Since the late nineteenth cen- 8. Elaeocarpus serratus (Ceylon olive) 1998 + 17 tury, numerous fruit and ornamental trees 9. Eriobotrya japonica (loquat) 1991 + 3,7 originating from Southeast Asia have been 10. Ficus pumila var. awkeotsang (jellyfig) 1991 + 7,23 11. Litchi chinensis (litchi) 1991 + 3,7 introduced into Taiwan for planting in 12. Muntingia calabura (Indian cherry) (1997) + U residential areas and in the Kentin Tropical 13. Pachira macrocarpa (malabar chestnut) 1991 + 8,23 Botanical Garden in southern Taiwan (24). 14. Persea americana (avocado) (1988) – U It is probable that P. noxius was introduced 15. Prunus mume (Japanese apricot, plum) 1991 + 3,7,12 into Taiwan on diseased roots of these 16. Prunus persica (peach) 1999 + 8 exotic tree species. 17. Pyrus pyrifolia (pear) 1991 + 7,23 18. Syzygium samarangense (wax apple) 1992 + 4,7 Symptoms and Development 19. Sterculia nobilis (ping-pong) 1991 + 8,23 of the Disease 20. Vitis vinifera (grape) 1996 + 6,7 Ornamental trees Brown root rot may occur on trees of all 21. Acacia confusa (Taiwan acacia) 1995 – 14 ages. Disease development in most tree 22. Actinodaphne pedicellata (litsea) 1928 + 26 species is rapid (8). Foliage on a diseased 23. Aleurites fordii (tungoil tree) 1998 + 17 tree may change from normal color to pale 24. Alstonia scholaris (blackboard tree) 1998 + 17 green to brown within 1 or 2 months (Fig. 25. Araucaria cunninghamii (hook pine) 1998 – 17 1). This rapid tree death commonly is re- 26. Araucaria heterophylla (Norfolk Island pine) 1998 + 17 ferred to as quick decline. Some tree spe- 27. Bauhinia × hybrid (butterfly-tree) 1996 + 6,8 cies may bloom luxuriantly the year before 28. Bauhinia purpurea (purple bauhinia) 1996 + 6,8 29. Bauhinia variegata (orchid-tree) 1942 + 17,27 the onset of quick decline symptoms. For 30. Bischofia javanica (autumn maple tree) 1928 + 17,26 example, flame trees (Delonia regia) nor- 31. Bombax ceiba (silk cotton) 1998 + 17 32. Broussonetia kazinoki (small paper (1998) + U

mulberry) 33. Broussonetia papyrifera (paper mulberry) (1998) + U 34. Calocedrus formosana (Taiwan incense (1998) + U cedar) 35. Calophyllum inophyllum (Indian poon beauty 1995 – 17 leaf) 36. Camellia japonica (camellia) 1998 + 17 37. Cassia fistula (yellow golden shower tree) 1998 + 17 38. Casuarina equisetifolia (ironwood tree) 1995 – 17 39. Ceiba pentandra (1998) – U 40. Cerbera manghas (odollam cerberus tree) (1998) + U 41. Chamaecyparis formosensis (Taiwan red (1998) + U cypress) 42. Chorisia speciosa (floss silk tree) 1999 – 8 43. Chrysalidocarpus lutescens (yellow areca (1999) + U palm) 44. Cinnamomum kanehirai (stout camphor) 1998 + 17 45. Codiaeum variegatum (croton) 1928 – 26 46. Cryptocarya concinnai (Konishi crytocarya) (1998) + U 47. Cycas taiwaniana (Taiwan cycas) 1991 + 12,13 48. Dalbergia sissoo (sissoo tree) 1928 + 26 49. Delonix regia (flame tree) 1991 – 12,13 50. Diospyros ferrea var. buxifolia (Philippine (2000) + U ebony persimmon) 51. Diospyros oldhamii (oldham persimmon) (2000) + U 52. Duranta repens (creeping sky flower) 1928 + 8,26 53. Eucalyptus camaldulensis (murray red gum 1991 + 12,13 eucalyptus)

54. Eucalyptus citriodora (lemon gum 1991 + 12,13 Fig. 10. Geographic distribution of eucalyptus) Phellinus noxius in Taiwan. Each point 55. Eucalyptus grandis (maiden eucalyptus) 1991 + 12,13 represents a combination of host and 56. Ficus elastica (rubber plant) 1998 + 17 locality. Each number represents one of 57. Ficus microcarpa (small-leafed banyan) 1995 + 14 the following counties: 1, Taipei; 2, Tao 58. Ficus religiosa (botree fig) 1996 + 6,8 Yuan; 3, Hsin Chu; 4, I Lan; 5, Miao Li; 6, (continued on next page) Taichung; 7, Hua Len; 8, Nan Tow; 9, Chang Hua; 10, Yun Lin; 11, Chia Yi; 12, a +, first reported (or found) worldwide; –, first report was not from Taiwan.

Tainan; 13, Kaohsiung; 14, Taitung; 15, b U, unpublished. Pingtung.

822 Plant Disease / Vol. 86 No. 8 Table 1. (continued from preceding page) mally bloom sparingly in central Taiwan. Year first Reported However, flame trees with incipient infec- reported (or found) tions often flower profusely in the year Scientific name (common name) (or found) as new disease Citation preceding quick decline (Fig. 11A and B). Because infection originates from the roots 59. Firmiana simplex (Chinese parasol) 1998 + 17 near the basal stem, a large portion of the 60. Fraxinus formosana (island ash) 1998 + 17 trunk may have already been invaded by 61. Gardenia jasminoides (cape jasmine) 1928 + 26 62. Grevillea robusta (silver oak) 1996 – 6,8 the pathogen before the appearance of 63. Hibiscus rosa-sinensis (hibiscus) 1996 – 6,8 decline symptoms. This may reduce the 64. Hibiscus schizopetalus (fringed hibiscus) 1928 + 26 amount of water passing through the trunk 65. Hibiscus tiliaceus (linden hibiscus) 1998 – 17 to a level insufficient to support the whole 66. Hydrangea chinensis (Chinese hydrangea) 1928 + 26 tree, thereby triggering the development of 67. Keteleeria davidiana var. formosana 1998 + 17 flower buds and then the onset of quick (Taiwan keteleeria) decline (20). 68. Kigelia pinnata (sausage tree) 1999 + 8 Decline symptoms in other trees may 69. Koelreuteria henryi (flame gold rain tree) 1995 + 14 occur over periods of a year or more (8) 70. Lagerstroemia turbinata (crape myrtle) 1998 + 17 (Fig. 12). This slow decline may be the 71. Lagerstroemia speciosa (queen’s crape 1996 + 6,8 result of root infections originating at myrtle) greater distances from the trunk. This pro- 72. Lantana camara (lantana) 1998 + 17 73. Leucaena leucocephala (white popinac) 1998 – 17 gressive root destruction impairs carbohy- 74. Liquidambar formosana (maple) 1991 + 12,17 drate storage and water uptake and results 75. Litsea glutinosa 1998 + 17 in a more gradual defoliation (21). Host 76. Litsea hypophaea 1928 + 26 resistance and vigor, and pathogen isolates 77. Macaranga tanarius (macaranga) 1998 + 17 that are relatively nonaggressive, may also 78. Machilus zuihoensis (incense machilus) 1928 + 26 contribute to the slow process of disease 79. Maesa tenera (Taiwan maesa) 1928 + 26 development. When greater destruction of 80. Mallotus paniculatus (turn in the wind) (2000) + U the root system by P. noxius occurs on one 81. Melaleuca leucadendron (cajuput tree) 1996 + 6,8 side of the root system, the affected tree 82. Melia azedarach (China berry) 1928 – 26 may display yellowing and defoliation only 83. Melodinus angustifolius (narrow leafed (1999) + U on that side of the crown during the early melodinus) stages of disease development. 84. Michelia compresa (Formosan michelia) 1998 + 17 Roots infected with P. noxius initially 85. Michelia figo (banana magnolia) 1996 + 6,8 86. Muntingia calabura (1998) + U exhibit a brown discoloration of the wood 87. Murraya paniculata (orange jasmine) 1928 + 13,26 just beneath the bark (Fig. 2). In advanced 88. Neolitsea parvigemma (small bud neolitsea) (2000) + U stages of decay, the wood develops a soft,

89. Nerium oleander (oleander) 1998 + 17 stringy white rot with a conspicuous net- 90. Palaquium formosanum (Formosan nato tree) 1998 + 17 work of brown zone lines (Fig. 13). The 91. Pinus thunbergii (black pine) 1998 + 17 outer bark surface appears rough because it 92. Pistacia chinensis (Chinese pistache) 1998 + 17 is covered with a layer of adhering soil 93. Podocarpus macrophyllus 1995 – 14 particles and brown fungal mycelia (Fig. 94. Pongamia pinnata (pongamia) 1998 + 17 14). The inner bark is covered with the 95. Pterocarpus indicus (rose wood) 1998 – 17 white to brownish mycelial mat (Fig. 15). 96. Prunus campanulata (Taiwan cherry) 1999 + 8 Occasionally, thin, hard and flat basidio- 97. Osmanthus fragrans (sweet osmanthus) (1998) + U carps are formed on the basal trunks or 98. Rhododendron obtusum (rhododendron) (1998) + U exposed roots of diseased trees. The conks 99. Roystonea regia (royal palm) 1996 + 6,8 100. Salix babylonica (willow) 1995 + 14 are initially white with the context gradu- 101. Scheffera octophylla (scheffera) (1999) + U ally turning yellow to brown (Fig. 16). The 102. Sterculia foetida (hazel sterculia) 1999 + 8 conks eventually become brownish-gray or 103. Swietenia mahagoni (mahogany) 1995 + 14 dark gray (Fig. 17). 104. Tabebuia chrysantha (yellow golden bell (2000) – U tree) Dissemination and Survival 105. Taiwania cryptomerioides (Taiwania) 1998 + 17 of the Pathogen 106. Terminalia catappa (Indian almond) 1996 + 6,8 The way by which new infection centers 107. Terminalia boivinii (1998) + U of brown root rot are established is still 108. Ulmus parvifolia (Chinese elm) 1998 + 7 undetermined. It is likely that P. noxius is 109. Zelkova serrata var. serrat (zelkova) 1996 + 6,8 introduced into new areas on trees infected Special crops in the nursery and then planted in the land- 110. Camellia sinensis (tea) 1965 – 10 scape. The fungus may then spread to adja- 111. Cinnamomum camphora (camphor) 1928 – 13,26 cent trees through root-to-root contact 112. Cinnamomum zeylanicum (Ceylon cinnamon) 1998 + 17 (7,11) (Fig. 18). A brown root rot infection 113. Coffea arabica (coffee) 1943 + 28 center also may arise following coloniza- 114. Cordia dichotoma (cordia) 1998 + 17 Ã tion of a freshly cut stump by basidio- Herbaceous plants spores (11) (Fig. 18) and then mycelial 115. Artemisia capillaris (wormwood) 1998 + 17 movement from the stump to surrounding 116. Artemisia princeps (mugwort) (1997) + U 117. Ipomoea pescaprae 1998 + 17 healthy roots. However, this probably is 118. Lactuca indica (wild lettuce) 1998 + 17 not a common method by which P. noxius 119. Melicope merrilli (melicope) 1998 + 17 initiates new disease centers in Taiwan 120. Sauranja oldhami 1928 + 26 because the fungus rarely produces 121. Urena lobata (cadillo) 1928 + 26 basidiocarps on diseased trees in the field (8,13,14). Arthrospores produced by P.

Plant Disease / August 2002 823 Fig. 11. A 30-year-old flame tree (Delonia regia) in central Taiwan. A, 3 months before the appearance of quick decline; B, after the appearance of quick decline. (courtesy H. Y. Lu)

Fig. 12. Slow decline of a 20-year-old small-leafed banyan tree (Ficus micro- carpa) resulting from Phellinus noxius brown root rot.

Fig. 14. Outer surface of diseased lon- Fig. 15. Inner surface of bark of dis- gan roots (Dimocarpus longan) covered eased longan root (Dimocarpus longan) with a layer of adhering mixture of soil covered with a white to brown mycelial particles and brownish fungal mycelia mat of Phellinus noxius. of Phellinus noxius. lum. Currently, the most efficient method noxius in culture are probably not an im- of destroying the residual inoculum is by portant source of inoculum in nature be- flooding the field (15), and the most practi- cause they have never been observed in the cal way is to fumigate the infested soil field (11). with ammonia generated from urea After tree removal, P. noxius can survive amended in soil under alkaline conditions in colonized roots remaining in the soil for (5,16). Another approach is to replant the more than 10 years (15). It can also remain infested areas with resistant species (9). viable as mycelium in the rhizosphere for The recommended replacement species for several months. fruit trees are mango and citrus. For orna- mental trees, the locally popular species of Measures for Disease Control Alstonia scholaris is recommended. Al- Replanting of susceptible trees in in- though A. scholaris is listed in Table 1 as a fested soils is not recommended because host, inoculation tests show that it is very they may become infected after contact resistant to P. noxius (9). Fig. 13. A longan root (Dimocarpus lon- with mycelium in the rhizosphere or in gan) showing advanced white rot symp- buried roots (2) (Fig. 18). Many soil treat- Current Status toms caused by Phellinus noxius. Note and Future Outlook the conspicuous network of brown lines ments have been tested and numerous ex- permeating the white and soft wood periments have been performed to find an Besides Taiwan, P. noxius is widespread tissue. effective way of eliminating such inocu- in other parts of Southeast Asia and the

824 Plant Disease / Vol. 86 No. 8 South Pacific (25). Brown root rot may reports concerning the incidence of brown In this regard, seven of 45 fungicides have become a serious problem in these regions root rot may be expected in these regions been found to be strongly inhibitory to the if a large number of susceptible fruit and in the future. growth of P. noxius in vitro (5). These ornamental trees were planted in infested More information regarding the use of fungicides were further evaluated for their areas, or if tree seedlings from infested fungicides is needed to slow down and ability to control the disease in greenhouse nurseries were used for agricultural and hopefully stop disease development in experiments. The systemic fungicides tri- landscape plantings. Since P. noxius at- infected trees next to a dying or dead tree. adimefon, prochloraz, and mepronil were tacks a wide range of plant species, more found to be nonphytotoxic and effective in reducing disease incidence. Recently, each of these fungicides was applied to diseased grapevines in the field as a soil drench once every 3 months in combination with a soil amendment con- taining lime and urea. The treatments ap- pear to be promising, as no further decline or death of grapevines was recorded in the treated plots, while disease progress re- mained unchecked in the control plot. Thus, it appears likely that fungicides can be useful in managing disease develop- ment. Still to be determined is the recurrent rate of brown root rot after the termination of the treatments and the economic feasi- bility of the treatments. There is a wide range of susceptibility to Fig. 17. Mature fruiting bodies of Phel- brown root rot among different species of Fig. 16. Young fruiting bodies of Phel- linus noxius produced on a declining the same , and among different varie- linus noxius produced on a declining flame tree (Delonia regia). (courtesy J. ties of the same species (9). Disease resis- longan tree (Dimocarpus longan). H. Huang) tance needs to be further identified and

Fig. 18. Diagrammatic illustration of the disease cycle of Phellinus noxius brown root rot on susceptible trees.

Plant Disease / August 2002 825 characterized as a basis for development of New host records of Phellinus noxius causing under controlled conditions. Plant Pathol. commercially acceptable resistant fruit and brown root rot of fruit and ornamental trees in 48:337-344. Taiwan and response of horticultural plants to 17. Chang, T. T., and Yang, W. W. 1998. Phellinus ornamental trees through conventional the pathogen via artificial inoculation. noxius in Taiwan: Distribution, host plants and breeding and genetic engineering. (Abstr.) Plant Pathol. Bull. (Taiwan) 5:201. the pH and texture of the rhizosphere soils of 7. Ann, P. J., Lee, H. L., and Huang, T. C. 1999. infected hosts. Mycol. Res. 102:1085-1088. Acknowledgments Brown root rot of 10 species of fruit trees 18. Corner, E. J. H. 1932. The identification of Phellinus noxius We thank H. Y. Lu and J. H. Huang for supply- caused by in Taiwan. Plant the brown root fungus. Gard. Bull. Straits ing pictures used in Figures 11 and 17, respec- Dis. 83:746-750. Settl. 5:317-350. tively, and C. Y. Wong for assistance in checking 8. Ann, P. J., Lee, H. L., and Tsai, J. N. 1999. 19. Cunningham, G. H. 1965. Polyporaceae of the scientific names of host plants. This research Survey of brown root disease of fruit and or- New Zealand. N.Z. Dep. Sci. Indust. Res. Phellinus noxius was supported, in part, by grants from the Agricul- namental trees caused by in Bull. 164:221-222. tural Council of Taiwan, and National Science Taiwan. Plant Pathol. Bull. (Taiwan) 8:51-60. 20. Ko, W. H., and Kunimoto, R. K. 1996. Quick Council grant NSC87-2313-B-054-009 from Tai- 9. Ann, P. J., Tsai, J. N., Wang, I. T., and Hsieh, decline of macadamia trees: Association with wan. This is contribution 2084 from the Taiwan M. J. 1999. Response of fruit trees and orna- . Ann. Phytopathol. Soc. Jpn. Agricultural Research Institute. mental plants to brown root rot disease by ar- 62:37-39. tificial inoculation with Phellinus noxius. 21. Ko, W. H., Kunimoto, R. K., and Maedo, I. Plant Pathol. Bull. (Taiwan) 8:61-66. 1977. Root decay caused by Kretzschmaria Literature Cited 10. Anonymous. 1995. Tea brown root disease clavus: Its relation to macadamia decline. 1. Abe, Y., Kobayashi, T., Onuki, M., Hattori, T., and longan brown root disease. Agric. Rev. Phytopathology 67:18-21. and Tsurumachi, M. 1995. Brown root rot of (Taiwan) 4:141, 255. 22. Ko, W. H., Tomita, J., and Short, R. L. 1986. trees caused by Phellinus noxius in wind- 11. Bolland, L. 1984. Phellinus noxius: Cause of Two natural hosts of Kretzschmaria clavus in breaks on Ishigaki Island, Japan – Incidence a significant root rot in Queensland hoop pine Hawaiian forests. Plant Pathol. 35:254-255. of disease, pathogen and artificial inoculation. plantations. Aust. For. 47:2-10. 23. Lee, H. L., and Huang, T. C. 1991. Prelimi- Ann. Phytopathol. Soc. Jpn. 61:425-433. 12. Chang, T. T. 1991. Phellinus noxius causing nary studies on wilt disease of custard apple. 2. Ann, P. J., and Ko, W. H. 1991. Association of root rot and collar rot of several tree species (Abstr.) Plant Prot. Bull. (Taiwan) 33:433. in Taiwan. (Abstr.) Plant Prot. Bull. (Taiwan) Phellinus noxius with decline of longan 24. Liu, T. R., Wang, J. L., and Liao, R. J. 1967. 33:432. (Euphoria longan) trees. (Abstr.) Phytopa- Exotic plant species in Taiwan. Taiwan For. 13. Chang, T. T. 1992. Decline of some forest thology 81:1232. Bull. 3:114-167. 3. Ann, P. J., and Ko, W. H. 1991. Association of trees associated with brown root rot caused by 25. Pegler, D. N., and Waterston, J. M. 1968. Phellinus noxius with root rot of fruit trees in Phellinus noxius. Plant Pathol. Bull. (Taiwan) Phellinus noxius. No. 195 in: Descriptions of Taiwan. (Abstr.) Plant Prot. Bull. (Taiwan) 1:90-95. Pathogenic Fungi and Bacteria. Commonw. 33:432-433. 14. Chang, T. T. 1995. Decline of nine tree spe- Mycol. Inst., Kew, England. 4. Ann, P. J., and Ko, W. H. 1992. Decline of cies associated with brown root rot caused by 26. Sawada, K. 1928. Camphor tree decline. longan trees: Association with brown root rot Phellinus noxius in Taiwan. Plant Dis. Descript. Catal. Formosan Fungi 4:86-91. caused by Phellinus noxius. Plant Pathol. 79:962-965. Bauhinia Bull. (Taiwan) 1:19-25. 15. Chang, T. T. 1996. Survival of Phellinus 27. Sawada, K. 1942. decline. Descript. 5. Ann, P. J., and Ko, W. H. 1994. Studies on noxius in soil and in the roots of dead host Catal. Formosan Fungi 7:97-98. ecology of brown root rot of fruit trees caused plants. Phytopathology 86:272-276. 28. Sawada, K. 1943. Coffee decline. Descript. by Phellinus noxius and disease control. 16. Chang, T. T., and Chang, R. J. 1999. Genera- Catal. Formosan Fungi 8:149-150. (Abstr.) Plant Pathol. Bull. (Taiwan) 3:69. tion of volatile ammonia from urea fungicidal 29. Tai, F. L. 1979. Sylloge Fungorum Sinicorum. 6. Ann, P. J., Lee, H. L., and Huang, T. C. 1996. to Phellinus noxius in infested wood in soil Science Press, Academia Sinica, Peking, China.

Pao-Jen Ann Tun-Tschu Chang Wen-Hsiung Ko Dr. Ann is a senior researcher of the Dr. Chang is a principal scientist and Dr. Ko is professor of plant pathology at Department of Plant Pathology, Taiwan head of the Forest Protection Division of Beaumont Agricultural Research Center Agricultural Research Institute, Tai- Taiwan Forestry Research Institute, of the University of Hawaii. He received chung, Taiwan. She received her B.S. Taipei, Taiwan. He received B.S. and his B.S. degree from National Taiwan and M.S. degrees from National Taiwan M.S. degrees from National Taiwan University and his Ph.D. degree from University at Taipei, Taiwan, and her University at Taipei, Taiwan, and his Michigan State University. His research Ph.D. degree from the University of Ph.D. degree from the University of interests include ecology and biological Hawaii. Her current research interests Hawaii. His current research focuses on control of soilborne diseases of tropical include fungal diseases of fruit trees root diseases of woody trees caused by fruit crops and biology of Phytophthora. and etiology and control of diseases Basidiomycetes and of wood- He received the Ruth Allen Award in caused by species of Phytophthora. inhabiting Aphyllophorales. He received 1984 from the American Phytopatho- She received the Agricultural Research the Outstanding Research Award from logical Society for his contribution in hor- and Development Award from the the National Science Council of Taiwan monal regulation of sexual reproduction Department of Agriculture and Forestry in 1996. in Phytophthora and is a Fellow of the of Taiwan in 1997. American Phytopathological Society.

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