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 ผลงานตีพิมพ์ในวารสารวิชาการResponses to mass selection in a domesticated population of snakeskin gourami, Trichopodus pectoralis, Regan 1910, and confounding effects from stocking densitiesผู้แต่ง: Dr.Satid Chatchaiphan, Assistant Professor , Mr.Chatchai Thaitoongchin , Dr.Skorn Koonawootrittriron, Associate Professor , Dr.Uthairat Na-Nakorn, Professor , วารสาร:   
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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effects of planting times and plant densities of top-shoot cuttings on multiplication of breeder seed potato) ผู้เขียน: Md. Abdullah Al Mamun, Abdullah Al-Mahmud, Mohammad Zakaria, M. Mofazzal Hossain, Md. Tofazzal Hossain สื่อสิ่งพิมพ์:pdf AbstractTop-shoot cuttings were planted with the whole tuber (as a control) at different dates using three spacings at the Horticultural Research Farm of Bangabandhu Sheikh Mujibur Rahman Agricultural University to evaluate the performance of top-shoots as planting material and to determine the optimum time of planting and the optimum spacing for top-shoot cuttings as planting material for breeder seed production. The survival of top shoot cuttings was more than 97.8% irrespective of the planting time and plant spacing. Significant variations were found among the treatment combinations for plant height at 45 and 60 days after planting (DAP), foliage coverage at 45 and 60 DAP, number of branches per plant, number of tubers per plant, individual tuber weight, tuber yields per plant and per hectare yield. The highest mean yield (46.57 t/ha) was produced by whole tubers planted on 10 November with 50 10 cm spacing which was similar to whole tubers planted on 1 November with 50 10 cm spacing. On the other hand, plants from top-shoot cuttings yielded 34.82 t/ha in T3S2 followed by T1S1 (33.34 t/ha), T3S3 (30.70 t/ha). The total yield of potato increased 122.8% from a single, early crop due to taking two repeated cuttings compared with 89.6% from a single late crop. Early planting of top-shoot cuttings with closer spacing (50 10 cm and 50 15 cm) is recommended for the multiplication of breeder seed potato. |
 ที่มา:คณะประมง มหาวิทยาลัยเกษตรศาสตร์หัวเรื่อง:การอนุบาลปลานวลจันทร์ทะเล (Chanous chenos, Forskal) ในถังไฟเบอร์ที่มีความหนาแน่นต่างกัน 3 ระดับ หัวหน้าโครงการ:ดร.วุฒิชัย อ่อนเอี่ยม |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Appropriate Postlarval Age and Stocking Densities of Litopenaeus vannamei Boone for Rearing in Low Salinity Water) ผู้เขียน:แก้วตา ลิ้มเฮง, ดร.ชลอ ลิ้มสุวรรณ, รองศาสตราจารย์ , ดร.นิติ ชูเชิด, รองศาสตราจารย์ , ดร.วราห์ เทพาหุดี, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractThe objective of this study was to evaluate under laboratory conditions the survival and growth rate of postlarvae (PL, where PLx represents the age at day x) at the stages of PL8 and PL10 of Litopenaeus vannamei during 62 d of rearing in water with low salinity levels of 1 and 3 parts per thousand (ppt) with three different stocking densities. The experiment consisted of 12 treatments with three replicate tanks per treatment: treatment 1 (1 ppt, PL8, 60 PL/m2); treatment 2 (1 ppt, PL8, 90 PL/m2); treatment 3 (1 ppt, PL8, 120 PL/m2); treatment 4 (1 ppt, PL10, 60 PL/m2); treatment 5 (1 ppt, PL10, 90 PL/m2); treatment 6 (1 ppt, PL10, 120 PL/m2); treatment 7 (3 ppt, PL8, 60 PL/m2); treatment 8 (3 ppt, PL8, 90 PL/m2); treatment 9 (3 ppt, PL8, 120 PL/m2); treatment 10 (3 ppt, PL10, 60 PL/m2); treatment 11 (3 ppt, PL10, 90 PL/m2); and treatment 12 (3 ppt, PL10, 120 PL/m2). Each 500-L fiberglass tank was equipped with adequate air diffusion and a submersible heater to maintain the temperature at 29+1oC. Shrimp were fed a commercial feed four times daily. Water samples were analyzed for concentrations of Ca2+, Mg2+, Na+, K+ , Cl- and SO4 2- ions every 10 d. After 62 d, shrimp were harvested. There were significant (P<0.05) differences in survival rates of shrimp between postlarvae reared in water with a salinity of 1 ppt and 3 ppt. The survival and growth rates of treatments 7-12 (PL8 and PL10, 60-120 PL/m2) reared in a salinity of 3 ppt were 80.9%, and 0.034 g/d, respectively. However, there were significant (P>0.05) differences in the survival rate and final weights of shrimp with either PL8 or PL10 at the same stocking rate and reared in water with a salinity level of 1 or 3 ppt. The concentrations of six major ions (Mg2+, Ca2+, Na+, K+, Cl- and SO4 2-) in water with a salinity level of 3 ppt (treatments 7-12) were significantly (P<0.05) higher than those in water with a salinity level of 1 ppt (treatments 1-6) throughout the experiment. The results of the present study indicated that in order to achieve good survival and growth of L. vannamei, PL8-PL10 should be stocked with a density of not more than 60 PL/m2 at 1 ppt or at a stocking rate between 60 and 90 PL/m2 at 3 ppt. |