Monday August 12 cipal environmental stimuli for flowering in myoga was required to aid in se- Symposium 11 (S11): Asian Plants with Unique lection of suitable production locations. Initial crop evaluation trials have es- Horticulture Potential: Genetic Resources, Cultural tablished that there are two apparently different cultivars, one of which pro- duced few flower buds at 420S latitude, deeming it unsuitable for further com- Practices and Utilization mercial production. Photoperiod was therefore considered to be a potentially important factor regulating flowering in the commercial production of myoga. Monday · August 12 Both cultivars were used in this trial. Plants grown under long day conditions (16 h) and short day conditions (8 h) with a night break produced flower buds, Location: Metro Toronto Convention Centre, Room 205CD while those under short day conditions (8 h) did not. The failure of plants un- der short day conditions to produce flower buds was due to abortion of devel- 1100–1140 oping floral primordia rather than a failure to initiate inflorescences. It was S11–O–1 concluded that for flower development in myoga a qualitative long day require- ORIENTAL VEGETABLES—HISTORY AND STATUS OF VEGETABLE ment must be satisfied however flower initiation is day-neutral. Short day con- INDUSTRY IN CHINA ditions resulted in abortion of flower primordia, premature senescence of foli- Dongyu Qu* age and reduced foliage dry weight in both cultivars. Early senescence and low Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, flower bud yield of the Inferior cultivar but not the Superior cultivar have been Beijing, China 100081 observed in crop evaluation trials in Southern Australia and New Zealand. Dif- ferences in critical photoperiod between the two cultivars may explain this ob- China is largest vegetable production in the world, which accounted for 75% servation and a second trial was designed to confirm this. Both cultivars were vegetable output in Asia. The sharing production per capita in a year reached as grown under three daylength treatments; 10, 12 and 14 hour daylengths and high as 330 kg (net consumption per capita is about 200 kg). The sustainable were destructively harvested on three separate occasions to determine if initia- increase is due to economical reform, expanding growing area, popularization of tion had occurred. From this data the critical daylength for each cultivar was F hybrids and improvement of production condition. The establishment of veg- 1 established and may be used as an important consideration in site and planting etable seed industry helped to speed up this process. The institute based enter- date selection for specific cultivars. prises played key role in the marketing new technology and their efforts brought the booming of vegetable industry. The future priority for vegetable technology 1220–1240 development should focus on the quality enhancement, applied research for cre- ation of desirable breeding materials and post harvest technology. Breeding en- S11–O–4 vironment friendly vegetables is important topic in the future. China has tremen- NEW LETTUCE PRODUCTION SYSTEM USING AUTOMATIC dous potential for vegetable industry not only supplying for Chinese market but REAPING HARVESTER AND RAIL SYSTEM also other countries, which can contribute the food security for this planet. Let us Toru Maruo*, Shigehiko Akimoto*, Noriko Wada*, Michiko Takagaki*, Yutaka share the Chinese history and share horticultural diversity to improve the veg- Shinohara* etable basket in other part of world. Faculty of Horticulture, Chiba Univ., 648, Matsudo, Chiba, Japan, 271-8510 New production system using rail system and automatic reaping harvester 1140–1200 was developed for lettuce. With this system labor–saving and better efficiency S11–O–2 of harvest works should be achieved in lettuce production. In the meantime, the EFFECTS OF CHITOSAN OF DIFFERENT MOLECULAR WEIGHT harvested leaves could be distributed directly as cut vegetables and packing ON RESPIRATION, GROWTH, AND NUTRITIONAL QUALITY OF process might also be simplified. Leaf lettuce (Lactuca sativa L.) was cultivated SOYBEAN SPROUTS under protected conditions. A rail system developed for tea plantation was in- Sung-Bae Kim, Young-Sang Lee*, Young-Sook An, Soon-Ryang Park, Seung- troduced in the plastic house and set up along the cultivation bed. This rail Hun Lee system was used not only for harvest but also for soil and planting bed prepa- Div. of Life Sciences, Soonchunhyang Univ., Shinchang-Myon Eupnae-Ri, Asan, ration. The harvesting system we used was automatic reaping harvester devel- oped from the tea harvester moving on the rail system. With this system, upper Chung-Nam, South Korea, 336-745 leaves were reaped off at a specific height precisely, allowing the plants to To clarify the molecular weight-dependent chitosan effects on production of regenerate new leaves for successive harvest. Lettuce plug seedlings were soybean sprouts, soybean seeds were soaked with 1,000 ppm chitosan of low planted two times (14 Sept. and 19 Nov. 2000) at 3 planting densities. The (LMW: 2,000 < M.W. < 10,000), medium (MMW: 50,000 < M.W < 100,000), and influences of the planting density and reaping height of the lettuce plant on the high (HMW: M.W. > 1,000,000) molecular weight. Sprouts treated with HMW yield and quality of the products were examined. The efficiency of this harvest exhibited significant increment in respiration rate by 5% within 1 day after soak- system was also evaluated by the time used for harvest. As far as planting ing. Chitosan effectively increased soybean sprout growth in that harvested sprouts density, higher yield was obtained with higher density planting. About reaping treated with HMW resulted in 3%, 1%, 3%, 1%, and 12% increase in total length, height, raping at 13 cm from the soil surface resulted in higher yield than at 8 hypocotyl length, root length, hypocotyl thickness and fresh weight, respectively. cm. With this system, total yield was higher in comparison with conventional These growth enhancing effects of chitosan were proportional to its molecular system and about 15 reaping could be executed. The time required for harvest- weight. Chitosan treatment caused no adverse or promotive effects on vitamin C ing 1 m2 area of lettuce with this system was only 15 seconds and this means contents, and chlorophyll formation in sprout cotyledons, an important factor on almost 1/100 harvesting time reduction as compared with conventional cul- quality of soybean sprouts, was slightly reduced by chitosan soaking. In conclu- ture. We concluded this production system should be feasible for leaf veg- sion, soaking soybean seeds with chitosan, especially high molecular weight, etables with high harvest efficiency. More advanced research should be con- seems to be an effective way to enhance productivity of soybean sprouts. ducted for this system about application to other vegetables for the process of washing, sterilization, packing. 1200–1220 S11–O–3 1340–1440 THE IMPORTANCE OF PHOTOPERIOD IN CULTIVAR AND SITE S11–P–5 SELECTION FOR PRODUCTION OF MYOGA (ZINGIBER MIOGA GENETIC DIVERSITY OF AN EUROPEAN COLLECTION OF LOQUAT ROSCOE) [ERIOBOTRYA JAPONICA (THUMB) LINDL.] K. Stirling*, R. Clark, S. Wilson, P. Brown Maria L. Badenes*, Teresa Canyamas, Carlos Romero, G. Llácer TIAR, School of Agricultural Science, Univ. of Tasmania, Hobart, Tasmania, Aus- Instituto Valenciano de, Investigaciones Agrarias, Apartado Oficial, Moncada, tralia, 7001 Valencia, Spain, 46113 Myoga (Zingiber mioga Roscoe) is a potential new crop in Australia. Flower Loquat [Eriobotrya japonica (Thumb) Lindl.] was introduced in Europe in 18th buds are harvested for fresh market sales. Consequently, identification of prin- century. It was first introduced as an ornamental tree. Later, when types with 298 XXVIth International Horticultural Congress Monday August 12 larger fruits were selected, it was grown for its fruits. In Europe, the plant was cording to our information, this is the first report for this species from Iran. grown in regular orchards at the beginning of the 20th century. At present, this species is an interesting alternative into the European fruit industry. A germplasm 1340–1440 collection from a survey made in Spain and accessions introduced from Japan, S11–P–8 Italy and Portugal was studied by means of RAPD markers. Among 46 acces- BOLTING AND FLOWERING IN LATE-BOLTING RADISH AS sions, 34 highly reproducible markers were selected. The polymorphism de- INFLUENCED BY GA4+7 AND GA3+PDJ TREATMENT tected allowed to distinguish 39 accessions. Two groups of accessions, that 1 2 2 shared the same combination of RAPD markers, could not be distinguished. Chung-Kil Kang* , Seung-Ho Kim , Ki-Hwan Jung One group included five accessions known as budsports from ‘Algeri’, the most 1Bioregulator Lab., Dept. of Crop Protection, NIAST, RDA, Suwon, Kyung-gi important cultivar grown in Spain. A second group included two accessions Do, Korea, 441-707; 2Breeding Research Institute, Seed Div., Dongbu Hannong surveyed in the same local area of Spain. Our results suggested that, although Chemicals, Ansung 456-933, Korea a large number of new accessions were identified, the genetic diversity of lo- This experiment was conducted to evaluate the bolting and flowering re- quat introduced in Europe is very low. It seems that a few forms were intro- sponse in late-bolting radish as influenced by several plant growth regulator duced from Japan. The species was propagated by seeds and developed many treatments from 2000 to 2001. Spray application of bioregulators at different S11 budsport, however the genetic base is narrow. For the future breeding and im- concentrations was made in a greenhouse near Yangsung-myun, Ansung-si, provement of the crop, it is necessary to broaden the collection by means of Korea. First of all, we selected 3 late-bolting radish lines based on the degree introduction of new plant material from Japan or China. of sensitivity to bolting. In addition, we evaluated several plant growth regula- tors to promote the bolting and flowering in the selected late-bolting radish 1340–1440 genotypes.