Studies on Sustainable Agriculture and on Genetic Resources

1.环境保护与可持续农业：对中国地区土壤有益微生物防治土壤病的方法进行了研究，以期开发一种新的害虫防治技术。在此背景下，还研究了中国的本土昆虫种类调查及其与日本本土昆虫的生态轨迹。此外，还走访了绍兴鸭养殖场，研究了该地区常规家畜的饲养制度和管理。这些母鸡被喂以一种特定的饲料混合物，添加在邻近河流中生长的水葫芦(Eichhornia Crassipe)，排泄物被丢弃到河里。这种管理系统非常有效地利用了当地的环境条件，但劳动效率不高：8,000只母鸡由三名员工饲养。虽然这种比较传统的管理是符合区域环境保护的，但如果农场计划进行规模化饲养和生产，就需要改进。2.新遗传资源的开发及其应用：为提高水稻产量和品质，选育了杂交水稻品种。目前，中国种植的水稻中有50%以上是杂交品种，预计糙米产量高达每公顷0.1吨。在种子收集方面，预计需要1/100或1/200编队的繁殖场，以进行充分的种子收集。在浙江和安徽沿江的山地高地地区，水稻种植在河岸的稻田里或山坡上的梯田里。玉米、大豆和红薯生长在山脚下的旱地上。玉米与小麦或大麦轮作，在三年内生产四种作物，这使得农民能够维持他们赖以生存的粮食生产。

1. Environmental protection and sustainable agriculture : Current methods of controlling soilbome diseases using beneficial soil microorganisms in China were investigated to develop a new technology for pest control. Also studied in this context were survey of indigenous insect species in China and their ecological trails in relation to those in Japan. Besides, the poultry farm raising Shaoxing duck, the most common species for egg production, was visited to study their feeding system and management for the conventional livestock in the region. The hens were fed with a specific feed mixture supplemented with water hyacinth (Eichhornia crassipes) growing in an adjacent river, and the excretions were discarded into the river. This management system exploits the local environmental condition very effectively but is not labor-efficient : 8,000 hens are raised by three employees. Although this rather traditional management is in accordance with regional environmental conservation, improvements will be needed if the farm plans to operate mass raising and production. 2. Exploration of new genetic resources and their applications : Hybrid rice cultivars have been bred to improve yield and quality of rice production. Currently, more than 50 % of rice growing in China is hybrid cultivars, and the yield of unhulled grain is expected to be as high as 0.1 tons per hectare. For seed collection it is expected that a breeding field in a 1/100 or 1/200 formation is needed for adequate seed collection. In the region of mountainous highlands along rivers in Zhejiang and Anhui Provinces, rice is grown in paddies in riverbanks or terrace on the hillsides. Maize, soy bean and sweet potato are grown in upland fields in foot areas of mountains. Maize is rotated with wheat or barley to produce four crops in three years, which allows the farmers to sustain food production for their subsistence.