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61.
Effects of salinity, light and temperature on growth rates of two species of Gracilaria (Rhodophyta)
Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32~C, 30 and 240 μmol/(m2·s) for G. lichenoides, and 24℃, 20 and 200 μmol/(m2.s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30℃, 32.10, and 287.23 μmol/(m2·s) for G. lichenoides (16.26%/d), and 25.38℃, 21.10, and 229.07 μmol/(m2·s) for G. tenuistipitata (14.83%/d), respectively. 相似文献
62.
Effects of salinity, light and temperature on growth rates of two species of Gracilaria (Rhodophyta) 总被引:2,自引:0,他引:2
Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G. tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained
under the conditions of 32°C, 30 and 240 μmol/(m2·s) for G. lichenoides, and 24°C, 20 and 200 μmol/(m2·s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions
for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30°C, 32.10, and 287.23 μmol/(m2·s) for G. lichenoides (16.26%/d), and 25.38°C, 21.10, and 229.07 μmol/(m2·s) for G. tenuistipitata (14.83%/d), respectively.
Supported by the 908 Special Program (908-02-04-07), the National Basic Research Program of China (973 Program, No. 2006CB400608),
and K. C. Wong Magna Fund in Ningbo University 相似文献
63.
Synedra ulna var, repanda Q. X. Wang & Q. M. You, a new variety of Synedra (Bacillariophyta) from Xinjiang, China, is described and illustrated, and the characteristic of the variety: includes undulate-linear valves and straight pseudoraphe, differs from other species of Synedra. 相似文献
64.
65.
The finding of shells of toheroa (Amphidesma ventricosum Gray) which had been drilled by gastropods absent from the littoral zone, is presented as evidence for the existence of sub‐littoral populations of toheroa. 相似文献
66.
The otoliths (sagittae) of 1076 tarakihi Cheilodactylus macropterus collected from around the whole of New Zealand during 1968–69 were examined for heavy metal content by atomic absorption spectrometry. Copper, cadmium, nickel, manganese, and zinc did not occur in significant quantities, but iron was present in amounts ranging from 0.5 μg to 7.0 μg per otolith. The iron appears to be largely contained in the nucleus of the otolith. Variations in iron content per otolith indicate three regions where iron content is similar: a northern region (mean 3.39 μg; σ2 = 1.35; n = 260); a central region (mean 1.92 μg; σ2 = 1.32; n = 741); and a southern region (mean 0.96 μg; σ2 = 0.45; n = 75). The significance of this regional variation, in otolith iron to the biology of the fish is not known, but may be linked by either heredity or environment to subpopulations of the fish. 相似文献
67.
建鲤与黄河鲤的RAPD分子标记及其杂交优势的遗传分析 总被引:3,自引:0,他引:3
利用RAPD技术对建鲤、黄河鲤及其杂交子代进行了遗传分析,筛选的33个引物共扩增出155条带,其中多态性片段为105条,片段S18-1600、S472-300具有种的特异性,可作为鉴别建鲤与黄河鲤的分子遗传标记。建鲤、黄河鲤及其正、反交子代群体内的遗传相似系数分别为0.8240、0.7921、0.7920、0.8569,黄河鲤与正交F1具有较高的遗传变异水平,反交F1变异最小。正交F1、反交F1与亲本(建鲤、黄河鲤)的遗传距离分别为0.2233、0.2436、0.1749、0.2026,说明子代均继承了较多的建鲤的遗传物质。分析了子代与亲本的RAPD标记类型以及各类型的条带数。应用PIT标记系统测定了子代的杂种优势并探讨了优势产生的遗传机理。 相似文献
68.
细基江蓠繁枝变型生长适宜环境条件的研究 总被引:12,自引:0,他引:12
于1985年4月-1986年3月对细基江蓠枝变型在广西池塘中的生长率作用年连续测定,研究几种主要环境因子对其生长的影响。结果表明,1.在广西地区池塘水温的年变化范围在15-32℃,藻体能周年生长;水温在20-30℃时生长较快;全年平均生长率为2.4% 2.对生长率和光合作用速率的适宜盐度范围为14-27,以21左右为最好。3.无机氮营养盐的浓度在4μmol/L左右,即可维持较快的生长率。4.栽培深 相似文献
69.
Liu Shicheng 《海洋学报(英文版)》1994,13(4):579-588
Ultrastructurestudyofthediatom──Ⅱ.Synedra,Cyclophora,Plagiogramma,Opephora,FragilariaandPseudostaurosira¥LiuShicheng(Received... 相似文献
70.
Gracilaria tenuistipitata vahang et Xia is cultivated at two different salinites(21,33) in the laboratory for 4 weeks,The daily growth rate is determined.The total agar yield and fractional agar composition are analyzed.Results show that algae grow faster in low salinity.The total agar yield is higher under high salinity conditions than under low salinity conditions.Among the eight fractions extracted,the yields of cold water extract and 40% ethanol extract are about the highest.In low salinities the yields of autoclaved extract and 60% ethanol extract are higher,while the yield of cold water extract is lower relative to high salinities. 相似文献