条斑紫菜(Porphyra yezoensis Ueda)自然附苗养殖的初步研究

浙江沿海岛屿很多，在那里紫菜自然附着生长，非常繁茂，为全国盛产紫菜地区之一。冬春季节当地群众开始采收紫菜作业，每隔半个月或二十天把岩石上生长的紫菜打下或拔下来，晒成干品。因此本项生产成为沿海居民的重要副业之一。不过用这种方式所生产的紫菜，因夹杂不少砂粒，加工粗糙，影响了产品的质量。

PRELIMINARY STUDY ON THE NATURAL CULTIVATION OF PORPHYRA YEZOENSIS UEDA

The experiments were carried on the coastal region of Putou Island from December.18.1963 to the middle of May 1964. For every 15 days or one month we put down inthe sea one net or two to which the natural spores would attach, then we observedthe appearance, growth and reproduction of the buds. At the same time, we put thethallus on the glass slide in the vessels to liberate the spores. After two days wesurveyed the germinating condition and form of the liberated spores. The experimental results are as follows: 1. The life history of Porphyra yezoensis Ueda cosists two stages, sexual repro-duction and asexual reproduction. The sexual reproduction begins from December to late March or early April. Theneutral spores begin to appear in the plant which is more than one cm to 10 cm inlength, but not in the plant less than 0.7 cm. The sexual reproduction begins from late December to June are early July. The car-pospores are liberated continuously until the plants disappear. The results correspondwith Kurogis (1961) report. 2. The period which the spores adhere to the nets is long. According to tableI, it is from December to early April in general.But we put down the nets earlier,the plants will grow longer and the products will be richer. Therefore the suitabletime for the spores to adhere to the nets is December or January. 3. At the first crop, according to the table 3, every square metre produced an average of 0.5 catty in dry weight.If we put down the nets in the middle ofDecember, and begin to cut in the early April then we may have 3-4 harvests andthe production will be increased greatly. Therefore this method for cultivating Porphyra yezoensis Ueda has an economic significance in the Chekiang region. 4. The time of the appearance of the neutral spores is comparatively long. Inthe course of our research on the reproduction of Porphyra yezoensis Ueda, it isknown that they play an important role in increasing the young buds in cultivation.This problem is worthy to be considered and must be settled, and thus we shouldutilize the neutral spores in the cultivation of the Porphyra yezoensis Ueda to theutmost.