Current status of Panama disease in Thailand RC PLOETZ Current status État de la maladie Estado de la enfermedad A VAZQUEZ of Panama disease de Panama en Thaïlande. de Panama en Tailandia. J NAGEL in Thailand. D BENSCHER University of Florida, IFAS ABSTRACT RÉSUMÉ RESUMEN Tropical Research Ouring a survey of banana­ Une enquête menée clans Una encuesta llevacla a cabo en and Education Center procluction areas in Thailancl, les régions de production de las regiones de proclucci6n ciel 18905 SW 280th Street Homestead, Florida 33031 -331 4 Kluai nam wa was essentially la banane en Thaïlande a montré banano en Tailanclia mostr6 que USA the only banana cultivar that que le cultivar Kluai nam wa était el cultivar Kluai nam wa era was affectecl by Panama clisease. pratiquement le seul à y être pr{icticamenteel t'111ico sienclo P SIANGLEW Four clifferent vegetative touché par la maladie de Panama. tocaclo por la enfermeclacl de S SRIKUL compatibility groups (VCGs) Quatre groupes de compatibilité Panama. Cuatro grupos de Suratthani Horticultural of the causal fungus, Fusarium végétative différents (VCGs) ont compatibiliclacl vegetativa Research Center oxysporum cubense PO Box 53 Muang f sp (FOC), été déterminés pour l'agent diferentes (VCGs) fueron Suratthani 84000 were recoverecl. VCG 01218 was pathogène impliqué, Fusarium cletenninaclos por el agence Thailand founclmainly in Southern oxysporum f sp cu.bense (FOC). pat6geno implicaclo, Fusarium Thailancl(provinces of Narathiwat Le groupe VCG 01218 a surtout oxy,porum f sp cubense (FOC). S KOOARIYAKUL and Yala), and prior to the survey été observé clans le sud du pays El grupo VCG 01218 fue sobre Chiang Rai Horticultural bac! only been collectecl in Java, (provinces de Narathiwat et de toclo observaclo en el sur ciel paîs Research Centre Muang District Chiang Rai 57000 Sumatra and peninsular Malaysia. Yala), et, avant cette enquête, (provincias de Narathiwat y de Thailand It may have been introclucecl il n'avait été collecté qu'à Java, Yala), y antes de esta encuesta, into Southern Thailancl from Sumatra et clans la péninsule solamente se colect6 en Java, W WATTANACHAIYINGCHAROEN these areas by Yawi-speaking malaysienne. Il aurait pu être Sumatra y en la penînsula Phichit Horticultural Muslim populations which resicle introduit clans le sud de la malasiana. Se poclrîa haber Research Center in these areas. VCG 01221 was Thaïlande à partir de ces régions introduciclo en el sur de Rongchang Muang Phichit 66000 founcl only in the north par les populations Muslim la Tailanclia a partir de estas Thailand (provinces of Chiang Rai and parlant le yawi et installées clans regiones por las poblaciones Nan), and constitutes a new VCG cette zone. VCG 01221 n'a été Muslim que hablan el Yawi e P LERTRAT for FOC. In contrast, VCGs 0123 trouvé que clans le nord instalaclas en esta zona. VCG Chanthaburi Horticultural and 0124-0125 were wiclespreacl, (provinces de Chiang Rai et de 01221 se encontr6 solamente en Research Center and hacl been previously reportecl Nan) et constitue un nouveau el norte (provincias de Chiang Rai Khung, Chanthaburi 221 1 O Thailand in the country. These results groupe de FOC. En revanche, y de Nan) y constituye un nuevo are cliscussecl in reference les groupes 0123 et 0124-0125, grupo de FOC. En cambio, los D WATTANACHAIYINGCHAROEN to the population structure of plus largement distribués, avaient grupos 0123 y 0124-0125, nüs Naresuan University the pathogen in Thailancl. déjà été signalés clans ce pays. abundantemente clistribuidos, Faculty of Agriculture Ces résultats sont discutés estaban ya senalados en este paîs. Natural Resources and par rapport à la structure Estos resultaclos son cliscutidos Environmental Sciences Phitsanulok 65000 des populations du pathogène respecta a la estructura de Thailand en Thaïlande. las poblaciones ciel pat6geno en Tailanclia. Received 5 October 1996 Accepted 9 April 1997 KEYWORDS MOTS CLÉS PALABRAS CLAVES Fruits, 1996, vol 51 , p 387-395 Thailand, Musa, plant Thaïlande, Musa, maladie Thailandia, Musa, © Elsevier, Paris diseases, Fusarium des plantes, Fusarium enfermedades de las oxysporum, vegetative oxysporum, groupe de plantas, Fusarium compatibility groups. compatibilité végétative. oxysp orum, grupo de compatibildad vegetativa. Fruits, vol 51 (6) 387 PLOETZ ET AL populations of the pathogen in Thailand via introduction vegetative compatibility analyses. Vegetative Bananas, Musa spp, are the most important compatibility groups (VCGs) represent clo­ fruit in Thailand (POLPRASID, 1990). During nally derived populations of fungal taxa a 1984-1985 census, the Department of (LESLIE, 1993). For an asexual taxon like Agricultural Extension determined that FOC, VCGs can provide important informa­ 197 000 ha were planted to the crop which, tion on population structure, as well as in turn, yielded an estimated 627 900 tons of insight into the origins of populations in a fruit. Bananas are used mainly for baby food given area and their relationships with popu­ and as dessert items, although many secon­ lations in other geographical locations da1y uses for the crop exist in the count1y. (PLOETZ, 1994). Thailand is located in the prima1y center of diversity for banana (SIMMONDS, 1962), and many different cultivars are grown in the materials and methods count1y; SILAYOI 0990) listed 58. Given this array of germplasm, it is surprising that 74% surveys of the land planted to banana in Thailand is Prior to 1995, tissue samples from banana of a single cultivar, Kluai nam wa ABB plants with symptoms of Panama disease (Pisang awak) (POLPRASID, 1990). Among the were collected in Thailandl. Monoconidial reasons for its popularity are the diverse isolates from LESLIE's samples were identi­ ways in which its fruit can be utilized (they fied as F oxysporum by NELSON2, and can be eaten either cooked or raw), and the fo1warded directly to PLOETZ for VCG deter­ cultivar's drought tolerance, a key asset in a minations. Samples collected by JONES, KooA­ country with a monsoon climate. RIYAKUL and SINGBURAUDOM were fo1ward­ ed to PEGG and MOORE3, in Australia. Unfortunately, Kluai nam wa is susceptible to Panama disease. This lethal, vascular During May and June, 1995, another survey disease, which is also known as fusarium was conducted in Thailand with a prima1y wilt, is caused by a soilborne fungus, Fusa­ objective of collecting FOC from areas that rium oxysporum f sp cubense (FOC). had not been covered during the above sur­ Panama disease is one of the most destruct­ veys. In total, the major banana-producing ive diseases that affects banana (PLOETZ, areas in the count1y had been assessed 1994). Known locally as 'tai-prai' (dies off),it when the 1995 survey was completed. was first reported from Thailand (Siam) by REINKING 0934), and is now recognized as a During the 1995 slllvey, ca 140 locations in major production constraint (VALMAYOR et al, Northern, Southern, Southeastern and Eas­ (1) Thefol/o wing individuals 1990). However, despite its importance, little tern Thailand were examined for Panama took part in the banana tissue disease. Locations were either sites in which sample collections: David is known about the disease and causal agent Jones, lnibap, Montpellier, in the count1y (SINGBURAUDOM, 1991). plants with external symptoms of Panama France; Surachart Kooariyakul, disease were observed, or were those with Chiang Rai Horticultural The present paper is a synopsis of Panama wild M acuminata. At ail locations, plants Research Centre, Chiang Rai, disease surveys conducted in Thailand were examined internally for symptoms of Thailand; John Leslie, Kansas during the 1990s, but focuses primarily on a Panama disease. Tissue pieces were collect­ State University, Department of Plant Pathology, Manhattan, survey conducted in 1995. Objectives of the ed mainly from plants with internai symp­ KS, USA; Narong latter mission were to collect FOC from areas toms, but additional samples were taken Singburaudom, Microbiology in Thailand that had not been previously from some asymptomatic plants to deter­ Division, Kasetsart University, surveyed, and to investigate whether wild mine whether these plants were also infect­ Chatuchak, Bangkok 10900, populations of Musa acuminata were affect­ Th ailand. ed by FOC. Ali tissue samples were partially ed by the disease in these areas. Ancilla1y dried by blotting in newspaper, and shipped (2) Paul Nelson, Pennsylvania State University, USA. objectives of this work were to summarize by airmail to RCP's laborato1y in the USA. (3) Ken Pegg and Natalie the known distribution of the disease and Upon receipt, tissue pieces were processed Moore, ODPI, lndooroopilly, clones that are affected in the count1y, and for recove1y of monoconidial isolates of FOC Australia. to assess diversity and relationships among as described previously (PLOETZ et al, 1994). 388 Fruits, vol 51 (6) CURRENT STATUS OF PANAMA DISEASE IN THAILAND . Seventy-three of the 78 samples were taken VCG determinations from symptomatic plants, and 57 of these Nitrate-nonutilizing (nit) mutants were gene­ (78%) yielclecl isolates chat coule! eventually rated for monoconidial isolates from LESLIE's be placed in one of four different VCGs and the 1995 surveys, and classified for nit (table !). Five isolates were in the VCG 0124- phenotype as described by CORRELL et al 0125 complex (PLOETZ, 1990), based on com­ (1987). NitM and nitl mutants were paired, patibility amongst testers for these VCGs, respectively, with nitl and NitM testers of and six isolates were in VCG 01218, a VCG VCGs 0120-01220 in the FOC collection of that hacl been reported previously from Java, PLOETZ. If complementation between nit Sumatra and peninsular Malaysia, but not mutants of the survey isolates and testers did Thailancl (PEGG et al, 1994) Four other iso­ not occur, additional NitM X nitl pairings lates were neither compatible with testers for were made among the non-complementing VCGs 0120-01220, nor with other isolates mutants. All complementation pairings were from the swvey. However, they were com­ conducted at least twice.