Ming-Fuh Chuang
Assistant Phytopathologist
Department of Plant Protection
Chia-yi Agricultural Experiment Station, TARI
Phone: 886-5-2771341 ext 227
Fax: 886-5-2773630
Education
B.S. (1987) in Department of Plant Pathology, National Chung Hsing University
M. S. (1989) in Department of Plant Pathology, National Chung Hsing University
Area of Research Interest
Application of Vesicular-arbuscular Mycorrhiza on Horticultural crops
Control of Plant Parasitic Nematode
Publication
Journal Papers
Chuang, M. F., Tzeng, K. C., and Hsu, S. T. 1989. Soft rot of radish caused by Erwinia carotovora subsp. carotovora and Erwinia chrysanthemi. Plant Prot. Bull. 31:358-365.
Bacterial soft rot of radish frequently occurs in Taiwan and was reported to be caused by Erwinia carotovora subsp. carotovora (Ecc). In 1988, a total of fifty strains of soft-rotting Erwinia was isolated from diseased radish tissues collected from several fields in the central and southern parts of Taiwan, among them, forty-six strains were identified as Ecc, while the other four strains were Erwinia chrysanthemi (Ech) with phenotypic characteristics similar to the strains in subdivision II according to Dickey's classification. Strains of both Ecc and Ech induced soft rot extensively on a wide variety of vegetable tissues. However, Ech strains were more virulent to bulb scales of onion than most Ecc strains. The rotting ability of Ech on radish taproot tissues was also stronger than that of Ecc especially at higher temperature (32℃). In addition, when radish taproot tissues were inoculated with cell suspensions of both Ecc and Ech in a 1:1 ratio, Ecc was dominant in the rotted tissues at 28℃or below, but Ech became dominant at higher temperature (32℃).
Cheng, Y. H., Chuang, M. F., and Tu, C. C. 1993. An estimate of effects of VA-mycorrhizal fungus Glomus clarum on muskmelon production. J. Agric. Res. China 42:74-84.
The VA mycorrhizal fungus Glomus clarum was proved to have the ability in colonization of root systems of muskmelon in pot culture test. Formation of VA-myocrrhiza in root systems caused by VAM fungus absorption of phosphorus and other soil mineral elements, and enhance the top growth of muskmelon seedlings, significantly. Up today the only method for production of VAM fungus inocula was propagated in the root systems of host plants. Among the five tested plants-corn, intotum, bahia grass, passion fruit, and muskmelon seedlings, corn and muskmelon were the best two host plants for propagation of G. clarum. In this study a procedure system was developed for production of inoculum source of G. clarum, including: 1. Maintaining the pure mycorrhizal fungus in pot culture of bahia grass (Paspalum notatum), 2. Propagation of mycorrhizal fungus in pot culture of corn, 3. Mass production of inoculum source of mycorrhizal fungus in sand bed culture of corn or muskmelon, 4. Collecting, air-drying and bagging the harvested culture soil which contained the segments of infested root systems of host plants and fungal chlamydospores. Application of VA-mycorrhizal fungus to field by transplanting VA-mycorrhizal seedlings were produced by inoculation of G. clarum to cultural medium. When the mycorrhizal seedlings were transplanted to the field, myocrrhizal root systems could show beneficial effects to muskmelon production. Mycorrhizal plants grew faster, and flowered earlier more than 7 days. The quantity as well as quality of fruits on mycorrhizal muskmelon were also increased. To analysis the economic effect of using mycorrhizal seedlings for production of muskmelon in plastic net house and PE sheet tunnel, the net incomes could increase up to about NT 22,700 dollars per 0.1 ha for plastic net house cultivation, while about NT 16,300 dollars per 0.1 ha for PE plastic sheet tunnel cultivation. Because the root systems were more healthy and abundant in mycorrhizal infected muskmelon plants, use of mycorrhizal plants combined with supply of sufficient nutrient and improvement of cultivation technique for ratoon cultivation could be successful in plastic house.
Conference Papers
Cheng, Y. H., and Chuang, M. F. 1991. Pespective of application of vesicular-arbuscular mycorrhizal fungi in seedling production. TARI Special Publication No. 35:227-236.
Healthy seedlings is one of the important factors affecting growth and yield of crops. Providing the best conditions to seedlings for growth and development is also important. Currently, a lot of crop species have been found to form mycorrhizae. This symbiotic structure played an important role to promoting growth of crops including citrus and many other crops. In the past decades, citrus industry in Taiwan was almost destroyed by likubin and soil-borne diseases. Therefore, healthy citrus seedlings via eliminating likubin pathogen and other systematic pathogens growing in sterile soils were used in the nursery. However, sterilization also killed mycorrhizal fungi in soils. Reintroducing mycorrhizal fungi into nursery soils to solve this problem is necessary. Research and development of practical application of VAM fungi for citrus seedlings has been conducted and will be further extended for other ecomonic crops. But inoculum production is still a problem need to be solved today. The results will be beneficial to practical application of VAM fungi and helpful to solve some problems in seedling production.
The vesicular-arbuscular mycorrhizal fungi was proved to have the compatibility with root systems of many crops. Formation of VA mycorrhiza in root systems of crops infected by VAM fungi could arise beneficial effects, i.e. promoted the growth and development of root systems, increased the absorption of soil mineral elements, enhanced the top growth of crops. Up today, the common method for propagation of VA mycorrhizal fungi were pot culture because they were obligate symbionts. Factors affected the propagation of VA mycorrhizal fungi in pot culture included host plants, soil(culture media), and environment. We developed a procedure for propagation of VAM fungal inoculum, including 1. maintaining the pure VA mycorrhizal fungus in pot culture of bahiagrass, 2. propagation of VA mycorrhizal in pot culture of corn, 3. mass production of VA mycorrhizal fungal inoculum in sand bed culture of corn or beggarlice, 4. air-drying and bagging the harvested culture soil containing the segments of infected root systems of host plants and fungal chlamydospores. Method for application of VA mycorrhizal fungi to field was by transplanting mycorrhizal seedlings of muskmelon pre-inoculated with cultural soil in plastic net house. When the mycorrhizal seedlings were transplanted to the field, mycorrhizal root systems could show beneficial effects to muskmelon production.
Cheng, Y. H., Chuang, M. F., and Hsu, S. L. 1995. Growth promotion of citrus inoculated with vesicular-arbuscular mycorrhizal fungi. TARI Special Publication No. 51:153-166.
Soil samples from 8 citrus orchard in Taiwan were collected to investigate the mycorrhizal ratio of citrus in native, results indicated that all root samples formed mycorrhiza in ratio, and high mycorrhizal formation and chlamydospores commonly presenced in the depth of 0-15 cm rhizospheral soil from soil level. Comparison of growth promotion of sunki seedlings inoculated with five VAM fungi Glomus aggregatum, G. geosporum, G. etunicatum, G. fasciculatum and G. mosseae, seedlings inoculated with G. aggregatum grew better than those inoculated with other four VAM fungi, but mycorrhizal colonization was not correlated with growth response of sunki. Difference of growth response of eight varieties of citrus rootstock inoculated with G. aggregatum was tested in greenhouse, results indicated that roots of all varieties of citrus rootstock were colonized by G. aggregatum, but height of inoculated rough lemon seedlings compared to non-inoculated ones increased 25.7 cm, followed by 23.8 cm of Troyer citrange(TC), height of inoculated citrumelo(SPB 4475) seedlings compared to non-inoculated ones increased only 11.5 cm was the lowest. Effects of soil texture on mycorrhizal formation of sunki seedlings were tested, mycorrhizal formation of sunki seedlings planted in sandy soil was the highest, followed by those planted in sandy loam, those planted in loam was the lowest, soil fertility level might be the causal factor, thereby height between inoculated and non-inoculated sunki seedlings planted in loam were not different.
Among the five tested plants-corn, beggarlice, bahiagrass, passionfruit and muskmelon, corn and muskmelon were the best two host plants for propagation of Glomus clarum. In this study, inoculum source of VA mycorrhizal fungi was propagated in pot culture of corn (or muskmelon)， then collected, air-dried and bagged the culture soil which contained the segments of infected root systems of host plants and fungal chlamydospores. In pot tests, growth response of mycorrhizal muskmelon, watermelon,and sponge gourd seedlings was better than non-mycorrhizal ones. The better method for field application was pre-inoculated, then transplanted the VA mycorrhizal seedlings to the field. In plastic net house and PE sheet tunnel tests, mycorrhizal muskmelon grew faster, and flowered earlier more than 7 days than non-mycorrhizal ones. The quantity as well as quality of fruits on mycorrhizal muskmelon were also increased. Because the root systems of mycorrhizal muskmelon grew in plastic net house were more healthy and abundant, combined with supply of sufficient nutrient and improvement of cultivation technique, ratoon cultivation of muskmelon could be successful.
Cheng, Y. H., and Chuang, M. F. 1997. Application of VA mycorrhizal fungi on fruit vegetable production. Sustainable Agriculture 6:28-31.