MARKETING POTENTIAL OF TAIWAN BANANA SEEDLINGS IN SOUTHEAST ASIA. Chih-Ping Chao

Transcription

1 MARKETING POTENTIAL OF TAIWAN BANANA SEEDLINGS IN SOUTHEAST ASIA Chih-Ping Chao

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3 MARKETING POTENTIAL OF TAIWAN BANANA SEEDLINGS IN SOUTHEAST ASIA Chih-Ping Chao 1, Su-Ying Lee 1, Chao-Yuan Chen 1 Tsu-Kwang Tzeng 1, and Sheng-Shing Liu 1 Taiwan Banana Research Institute, Chiuju, Pingtung, Taiwan cpchao_tbri@.yahoo.com.tw Abstract Banana is recognized as an important fruit crop and source of staple food worldwide. Establishment of micropropagation system will be essential for production of healthy tissue-cultured plantlets of banana. For stable production of banana, commercially released new cultivars selected by somaclonal variation technology such as Tai- Chiao No.7 is suggested to be planted especially in severely disease infested area. Banana has been listed as one of the potential tropical fruit crops ready to export from Taiwan. To increase competitiveness of Taiwan banana seedling industry for export in Southeast Asia, technologies such as certification of seedling production, virus indexing for different viruses, and development of specific molecular marker, need to be integrated. Keywords: Cavendish banana, Pei-Chiao, fusarium wilt, tissue culture, somaclonal variation Introduction Bananas (Musa spp.), which originated from tropical southeastern Asia, is not only used as a dessert fruit but also as a staple food. Currently, the annual global production is around 105 million MT, valued at 28,210 million US$ (2). They are grown in 150 countries and Asia s production is up to 67%, projected by the high productivity and volumes affordable in India and China. Among the total volume harvested annually, 18% of it is for export. Cavendish banana of AAA genome is the major variety for global trade and the Philippines is the largest export country just after Ecuador. Due to the fact that banana normally could be harvested within a year after planting and net profit could be cycled quickly, it is commonly considered as a cash crop or green gold. Therefore, bananas play very important role on economic, social and political grounds and offer livelihood for many small growers. To date, banana plant is commonly grown by small growers in perennial copping system, featured by its mat composition of a harvested residual mother stalk, a high plant developed from the daughter sucker (a follower), and a small granddaughter sucker just emerged from base of chopped mother stalk. On the contrary, annual cropping system is the dominant planting system in Taiwan, due to great concerns of typhoon damage and adjustment of peak production season to spring or fall season, instead of summer time (1, 12). Banana is a kind of perennial herbaceous crops and planting material is usually a vegetative sucker propagated, a corm, or a bit which is a piece of corm tissue. When traditional planting materials such as sucker is used by growers for replanting, 83

4 dissemination of pest and disease through infected sucker is quite possible if healthiness of planting material is not well checked. This was why banana bunchy top disease, devastated Fusarium wilt, or corm weevil became an epidemic quickly and caused severe loss in the past (8). To assure supply of clean and healthy planting materials to banana growers and sustain banana industry, Taiwan Banana Research Institute (TBRI) first established a micropropagation system for producing healthy Cavendish banana seedlings through tissue culture technology in 1983 (3). Outbreak of Fusarium wilt or so-called Panama disease, caused by Fusarium oxysporum f. sp. cubense race 1 (FOC R1), lead to severe damage of banana industry in Latin America in 1900s and forced the conversion of favorable variety Gros Mitchel there to Cavendish type banana (8). Since the resistance of Cavendish banana was overcome by a new race, race 4 of FOC, back to 1967 in Taiwan, competitiveness of Taiwan banana industry for export to Japan declined drastically. Besides the epidemic of FOC TR4 induced Fusarium wilt continuing to spread out to Australia, Canary island and South Africa in 1970s, severe impact on banana industries, caused by a more virulent strain of FOC R4, a new tropical race 4 (FOC TR4), has been recorded in Southeastern Asia countries such as China, Indonesia, Malaysia and the Philippines (10, 11) during , Jordan and Oman of middle East in 2012, and Mozambique of East Africa in 2013, respectively. How to mitigate the impact of Fusarium wilt on banana industry becomes a great concern globally and find solutions to slow down the disease rate by offering banana growers healthy TC plantlets of an acceptable new commercial cultivar with resistance to FOC TR4 are quite urgent tasks. Establishment of Micropropagation System for Production of Healthy Tissuecultured Plantlets of Banana To supply sufficient amount of high-quality TC seedlings of a specific banana cultivar ordered by banana growers or their associations on time, source of banana sucker for mass propagation should fulfill with criteria of genetic true-to-type, good yield capacity and bunch formation, and be collected one year in advance. Normally, thousand suckers of an ordered Cavendish variety such as Pei-Chiao should be collected in advance to propagate for 2 million plantlets in next year. Four different stages of micropropagating TC plantlets are tissue initiation, bud multiplication, plantlet regeneration, and nursery acclimatization (3). To assure pathogen-free of propagated TC plantlets, only soilless potting medium can be permitted to use and nursery stage should be well maintained in a 32-mesh screen house. To avoid the risk of mother stock material for subsequent subculture being affected by viral diseases such as BBTV and CMV in meristem tissue, enzyme-linked immunosorbent assay (ELISA) is adopted for virus indexing of (6) abovementioned viruses in mother stock materials for propagation at stage of tissue initiation. From 1984 to 2013, a total of 65 million plantlets (Fig 1) of Cavendish banana has been propagated and supplied to banana growers in Taiwan, and 65% of ordered TC plantlets are mainly planted between January and June, followed by 32% from October to December in a year. Advantages of using tissue-cultured plantlets include uniformed growth, high survival rate, synchronization of time to harvest, better fruit improvement, and lower cost. To strengthen sustainability of banana industry in Asia, a three-year project entitled Establishment of National Germplasm Repository, Multiplication and Distribution Center for Improved Varieties of Banana and 84

5 Plantain was conducted in by the Food and Fertilizer Technology Center (FFTC), co-sponsored by International Network for Improvement of Banana and Plantain (INIBAP), which has been renamed as Bioversity International, and technically supported by TBRI and National Taiwan University (7). Number of plantlets propagated by TBRI from Number of plantlets (x 10 6 ) Year Figure 1. Dynamics of tissue culture plantlets supplied by TBRI to banana growers in Taiwan From 1983 to 2013 Application of Somaclonal Variation to Breed New Cavendish Cultivar with Resistance to FOC TR4 Pei-Chiao is one of Cavendish varieties ordered most by banana growers in Taiwan. Good adaptation to different areas and image of an elite variety locally or in Japan make it the most favorable Cavendish variety (1). Presently, more than 60% of total growing acreage of banana, 13,000 ha, in Taiwan is established by Pei-Chiao. However, due to its high susceptibility to FOC TR4, banana plantation with more than 20% disease incidence will not be suitable for growing Pei-Chiao any more. Other alternative available to continue normal banana production in that infested land is the replacement of susceptible Pei-Chiao by planting materials of a resistant variety (4). By the unique recurrent selection of improved somaclonal variants from mother plant Pei-Chiao by TBRI since 1984, more than 10 clones with stable resistance to FOC R4 have been identified through evaluation of 40,000 TC plantlets of Pei-Chiao in a heavily infested plot (5). And all five commercial cultivars subsequently derived from improved somaclones, including Tai-Chiao No.1 in 1992 (Fig 2 ), Tai-Chiao No.3 in 2001, Formosana in 2002, Tai-Chiao No.5 (Table 1, Fig 3) in 2008(9), and Tai-Chiao No.7 (Fig 4) in 2013, which all show quite stable resistant reaction to FOC TR4 and retain acceptable horticultural traits at the same time. Since then, they have been registered as new cultivars and propagated, respectively, for TC seedlings suitable for growing in infested area. Both the first released somaclonal cultivar Tai-Chiao No. 1 and the high-yielding somaclone Formosana had a life span more than 12 years in spite of the fact that they were replaced gradually by somaclone Tai-Chiao No. 5 of which growth pattern and fruit formation is the most similar to Pei-Chiao. The amount of TC plantlets ordered per somaclonal cultivar in a year fluctuated a lot from million and are significantly affected by factors such as market price of banana before seedling order, yield capacity, management input, time needed from planting to harvest, etc. 85

6 Number of plantlets (x 10 6 ) Year Figure 2. Dynamics of Fusarium wilt resistant cultivar tissue culture plantlets supplied by TBRI to banana growers in Taiwan from 2001 to 2013 Table 1. Evaluation of horticultural traits, yield and resistance to FOC race 4 in TC plant derived from plantlet in Girth of No. of hand Bunch Resistance Plant height Clone pseudostem per bunch weight reaction to (cm) (cm) (kg/bunch) FOC race4 a TC b (Tai-Chiao No5) 286 a c 72.9 ab 7.5 b 20.0 b MR Pei-Chiao 262 ab 72.4 ab 8.4 a 26.2 ab HS a Resistance rating is defined as highly resistant (HR): disease incidence<10%; moderately resistant(mr): disease incidence between 10-25%; moderately susceptible (MS): disease incidence between 26-50%; and highly susceptible (HS): disease incidence>50%. b TC was registered as a new cultivar Tai-Chiao Nol.5 in 2008 c Means analyzed by Duncan s multiple range test with same alphabetic letter was not significantly different at p=0.05 level. 86

7 TC Pei-Chiao Fig. 3. Comparison of the resistant reaction of tissue culture plants of TC and Pei-Chiao in a FOC TR4 infested orchard (Left). Fruit bunch of plant of TC and Pei-Chiao (Right) harvested from a same banana orchard. Fig 4. Comparison of bunches of GCTCV-105 (L), Pei-Chiao (M), and GCTCV-2163 ( Tai-Chiao No.7 ) (R) selected from parent GCTCV-105. Ripened banana of Tai-Chiao No.7 (R). Marketing Potential of Newly Developed Somaclonal Cultivar in Southeast Asia Cavendish banana industries are the major income source in some southeastern countries such as China, the third largest country to produce banana, and the Philippines, the second largest exporter of Cavendish banana in the world (11). And Fusarium wilt caused by FOC TR4 has been reported in all Cavendish banana producing provinces of China, such as Fuchien, Guangdong, Guangxi, Hanan and Yunan Provinces. Similarly, Davao areas of Mindanao, the Philippines, where 80,000 ha of Cavendish banana is cultivated, also are threatened by the fast spread of FOC TR4 through using mechanic device in the field, infected planting material, soil and water. Fortunately, from the field surveys of promising banana new clones collected, deposited at International Germplasm Transit Center (ITC) of Bioversity International, and evaluation for those for improving livelihood of small growers worldwide, the Giant Cavendish Tissue Culture Variant-119 ( GCTCV-119 ) developed by TBRI has shown good resistant reaction to FOC TR4 in evaluation trial of Guangdong, China and Davao, the Philippines (Table 2) conducted by Banana Asia Pacific Network (BAPNET) of Bioversity International. Complied with policy-making of export seedling of potential tropical fruit crops in Taiwan to foreign market in the future, banana is also in the list if it could be produced through certified propagation system, virus-free and FOC-TR4 free, and protected by a specific molecular marker. Few multinational companies and local companies in the Philippines also showed high interest in purchasing TC plantlets of newly released somaclone cultivar such as Tai- Chiao No. 7 from TBRI. To protect intellectual property rights of Tai-Chiao No.7, TBRI is in the process of securing its variety registration in import countries of 87

8 Cavendish banana such as Japan and Korea as well as in production countries such as China and the Philippines. Table 2. Fusarium wilt incidence of different Cavendish cultivars in Davao de Norte, Philippines in 2009/2011 Cultivar Fusarium wilt (%) a Plant crop Ratoon crop Grand Naine 97 N/A Williams 94 N/A GCTCV GCTCV-219 b a Data was collected in the year of 2010/2011 by BAPNET b An improved clone selected from GCTCV-119 by Lapanday company in Davao, Philippines Conclusion To achieve good management of a banana plantation, accessibility of clean, healthy, true-to-type seedlings of an interested variety is a prerequisite. Through the initiation and successful development of micropagation system for production of healthy tissuecultured plantlets in Taiwan since 1983, not only banana industry in Taiwan is significantly improved but also greatly beneficial to many countries in southeastern Asia and the world where traditional planting materials for banana are commonly infected by disease or pest. Reason of Asia becomes the largest production center for banana should be closely related to the wide use of healthy TC plantlets. Nevertheless, when clean plantlets of the interested variety succumb to Fusarium wilt especially caused by FOC TR4, risk of crop loss is still inevitable. Once the disease pressure is high, replacement of original susceptible variety by a new commercial one with resistance to FOC TR4 will be the most effective approach. Cavendish banana is a dessert type banana and has been used for global trade for more than half century. To reduce its susceptibility to FOC TR4, many advanced technologies have been tried but without much success (11). Somaclonal variation, the unconventional breeding scheme, has been clearly demonstrated by TBRI and other international research units that it is the most feasible way to get higher frequency of variation through TC, up to 3-10 %, and select improved type from the offtypes (4, 5). Some severely infested field of Pei-Chiao could still keep normal production of banana continuously for 6-23 years after conversion of Pei-Chiao to somaclonal variants such as Tai-Chiao Taiwan. An integrative approach of healthy plantlet certification, virus indexing technology for BBTV, CMV, banana bandastreak virus (BSV), and development of molecular markers for variety protection is in its initiative stage. References Chen.C.H Production and marketing prediction of Taiwan banana. TBRI Annual Rpt. pp Market-UNCTAD.org 88

9 Hwang, S.C., C.L Chen., J.C. Lin and H.L. Lin Cultivation of banana using plantlet from meristem culture. HortScience 19: Hwang, S.C., W.H. Ko and C.P. Chao Control of fusarial wilt of Cavensih banana by planting a resistant clone derived from breeding. Plant Prot. Bull. (Taiwan) Special Pub. pp (In Chinese with English abstract). Hwang, S.C. and W.H. Ko Mutants of Cavendish banana resistant to race 4 of Fusarium oxysporum f. sp. cubense. Plant Prot. Bull. (Taiwan) 30: Hwang, S. C. and H.J. Su Production of virus-free Banana plantlets in Taiwan. Food and Fertilizer Development Center, Taipei, Taiwan. Extension Bull pp. Hwang, S.C Sustainable banana production through the use of tissue-cultured seedlings in Taiwan. TBRI Annual Rpt.: Jones, D.R Diseases of Banana, Abaca and Enset. CABI Publishing. 544pp. Lee, S.Y., Y.U. Su., C.S. Chou., C.C. Liu., C.C. Chen and C.P Chao Selection of a new somaclone cultivar Tai-Chiao No.5 (AAA, Cavendish) with resistance to Fusarium wilt of banana in Taiwan. Acta Hort. 897: Molina, A.B., E.G. Fabregar, V.O. Sinohin., G. Fourie., and A. Viljoen, Recent occurrence of Fusarium oxysporum f.sp. cubense Tropical Race 4 in Asia. Acta Hort. 828: Molina, A. B., C.P. Chao, M. E. R. Fabregar, E. Ramillete, M. Loayan, and V. G Sinohin Field resistance of Cavendish somaclone variants and local cultivars to Fusarium wilt (TR4) in the Philippines (Abst.). In: Symp. Unravelling the Banana s Genomic Potentia. Brisbane, Australia. Su, H.J., S.C Hwang., and W. H. Ko Fusarial wilt of Cavendish banana in Taiwan. Plant Dis. 70:

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