• Title/Summary/Keyword: Seed industry

Search Result 313, Processing Time 0.019 seconds

Studies on Seed Production of Saddleback Clownfish, Amphiprion polymnus 1) Spawning, Egg Development and Larvae Culture (Saddleback clownfish, Amphiprion polymnus의 종묘생산에 관한 연구 1) 산란과 난 발생 및 자치어 사육)

  • Yoon, Young-Seock;Rho, Sum;Choi, Young-Ung;Kim, Jong-Su;Lee, Young-Don
    • Journal of Aquaculture
    • /
    • v.18 no.2
    • /
    • pp.107-114
    • /
    • 2005
  • Clownfish are important and very popular fish in the ornamental aquarium industry. Demand for the fish is increasing dramatically. The present study was conducted to verify methods of broodstock management, patterns of spawning, rates of egg hatching and estimates of larval growth fur the saddleback clownfish, Amphiprion polymnus. Spawning occurred 8 times between August 2002 to June 2004 with 2 females and 1 male participating. Fertilized eggs were separated by an adhesive matrix and were oval in shape. The eggs were $2.46{\pm}0.13mm$ in size as measured along the longest axis. The percentage of fertilized eggs was 96.7%. Hatching was observed seven days post-spawning and hatching rate was 85.5%. The sizes of the newly-hatched larvae were $4.58{\pm}0.21mm$ TL (total length). Larvae had an open mouth and anus, and an oval yolk sac. At the 1 st day after hatching, the sizes of the larvae were $4.90{\pm}0.35mm$ TL. The larvae began to eat rotifers after complete yolk absorption. On the 5th day post-hatch, larvae were $5.88{\pm}0.31mm$ TL with complete fins and the survival rate was 48.6%. At 8 days after hatching, a band began to appear on head and back of the larvae indicating the beginning of metamorphosis. Metamorphosis was completed at an average TL of $15.00{\pm}2.12mm$ on the 23rd day after hatching. By the 45th day after hatching, juveniles averaged $22.76{\pm}3.22mm$ TL and survival rate was 28.4%.

Cultivation Support System of Ginseng as a Red Ginseng Raw MaterialduringtheKoreanEmpire andJapaneseColonialPeriod (대한제국과 일제강점기의 홍삼 원료삼 경작지원 시스템)

  • Dae-Hui Cho
    • Journal of Ginseng Culture
    • /
    • v.5
    • /
    • pp.32-51
    • /
    • 2023
  • Because red ginseng was exported in large quantities to the Qing Dynasty in the 19th century, a large-scale ginseng cultivation complex was established in Kaesong. Sibyunje (時邊制), a privately led loan system unique to merchants in Kaesong, made it possible for them to raise the enormous capital required for ginseng cultivation. The imperial family of the Korean Empire promulgated the Posamgyuchik (包蔘規則) in 1895, and this signaled the start of the red ginseng monopoly system. In 1899, when the invasion of ginseng farms by the Japanese became severe, the imperial soldiers were sent to guard the ginseng farms to prevent the theft of ginseng by the Japanese. Furthermore, the stateled compensation mission, Baesanggeum Seongyojedo (賠償金 先交制度), provided 50%-90% of the payment for raw ginseng, which was paid in advance of harvest. In 1895, rising seed prices prompted some merchants to import and sell poor quality seeds from China and Japan. The red ginseng trade order was therefore promulgated in 1920 to prohibit the import of foreign seeds without the government's permission. In 1906-1910, namely, the early period of Japanese colonial rule, ginseng cultivation was halted, and the volume of fresh ginseng stocked as a raw material for red ginseng in 1910 was only 2,771 geun (斤). However, it increased significantly to 10,000 geun between 1915 and 1919 and to 150,000 geun between 1920 and 1934. These increases in the production of fresh ginseng as a raw material for red ginseng were the result of various policies implemented in 1908 with the aim of fostering the ginseng industry, such as prior disclosure of the compensation price for fresh ginseng, loans for cultivation expenditure in new areas, and the payment of incentives to excellent cultivators. Nevertheless, the ultimate goal of Japanese imperialism at the time was not to foster the growth of Korean ginseng farming, but to finance the maintenance of its colonial management using profits from the red ginseng business.

Effect of Seed Mixture on Forage Yields and Botanical Composition at an Altitude of 400 m in Jeju island (표고 400m 제주 중산간 지역에서 혼합조합별 초지 생산성 및 식생구성)

  • Chae, Hyun Seok;Kim, Nam Young;Woo, Jae Hoon;Shin, Moon Cheol;Son, Jun Kyu;Seong, Pil Nam;Lee, Wang Shik;Kim, Si Hyun;Hwang, Kyung Jun;Kim, Young Jin;Park, Nam Gun
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.37 no.1
    • /
    • pp.19-27
    • /
    • 2017
  • The objective of this study was to determine the growth characteristics of cool (C1) and warm season grasses (C2) in pastures mixed with C1 and C2 at an altitude of 400 m in Jeju island to establishing pasture suitable for grazing horses and to evaluate the effect of pastures mixed with tall and short type grasses on the intake characteristics of horses. C1 used in this study was Kentucky bluegrass, redtop (short type grass) and tall type grasses were orchardgrass and tall fescue, respectively. Treatments of this study were consisted of four groups and the short type grass used in pastures mixed with C1 and C2 was mainly bermudagrass. Four treatment groups were follow as; Treatment 1 (bermudagrass + Kentucky bluegrass + redtop) 2) Treatment 2 (bermudagrass + tall fescue + orchardgrass) 3) Treatment 3 (Kentucky bluegrass + redtop) 4) Treatment 4 (tall fescue + orchardgrass). Bermudagrass was a little winter killing and inhibition of plant growth at an altitude of 400 m. Plant heights in pastures mixed with C1 and C2 were grown better than that in pastures mixed with C1. Especially, plant height in Treatment 4 was higher than other treatments. Dry matter yield was in the following order: Treatment 4> Treatment 3> Treatment 2> Treatment 1. Dry matter yield in pastures mixed with C1 increased as compared with pastures mixed with C1 and C2. Dry matter yield in Treatment 3 was higher than other treatments. In the first investigation regarding vegetation distribution, bermudagrass ratios among grasses in Treatment 1 and Treatment 2 were 11.7 and 13.3%, respectively. The growth of bermudagrass in winter was low due to the cold damage. However the growth of Kentucky bluegrass, redtop, tall fescue and orchardgrass was good. In the second investigation, bermudagrass ratios among grasses in Treatment 1 and Treatment 2 were 5.0 and 11.7%, respectively. Growth of forage in the second investigation was poor as compared to the first investigation. nutritive values(crude protein content, neutral detergent fiber content, acid detergent fiber content, digestibility) were good in pastures mixed with C1 Especially, nutritive values in pastures mixed with tall was higher than those of pastures mixed short grasses. P content among minerals in Treatment 1 was higher than other groups. However, the content of Ca, Mg and Mn were lower. The contents of Ca, K, Mg, Na, Cu, Zn and Fe in Treatment 2 were higher. However, the contents of K, Mg, Na, Cu, Zn and Fe in Treatment 3 were lower. Therefore, we suggest that cool season grasses with short grasses were sowed to establishing pasture suitable for grazing horses at an altitude of 400 m in Jeju island.