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....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℃, 30 and 240 μmol/（m^2·s） for G. lichenoides, and 24℃, 20 and 200 μmol/（m^2·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 lamol/（m^2·s） for G. lichenoides （16.26%/d）, and 25.38℃, 21.10, and 229.07 lamol/（m^2·s） for G tenuistipitata （14.83%/d）, respectively.展开更多
Gracilaria tenuistipitata varliui Zhang el Xia is cultivated at two different salinities (21, 33) in the laboratory for 4 weeks. The daily growth rate is determined. The total agar yield and fractional agar compositio...Gracilaria tenuistipitata varliui Zhang el Xia is cultivated at two different salinities (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.展开更多
Gracilaria tenuistipitata var Liui were mono cultivated and co cultivated with Pinctada martensii under high (33) and low (21) salinity conditions in laboratory. The daily growth rate of the alga was determined. Tissu...Gracilaria tenuistipitata var Liui were mono cultivated and co cultivated with Pinctada martensii under high (33) and low (21) salinity conditions in laboratory. The daily growth rate of the alga was determined. Tissue carbon and nitrogen contents, the yield and fractional composition of agar were analyzed. Results showed that: 1. Gracilaria grew better under low salinity conditions, the daily growth rate was twice that under high salinity conditions. Co cultivated algae grew faster than mono cultivated algae under low salinity conditions, the daily growth rate was about 37.6% higher. 2. Compared with mono cultivated algae, tissue nitrogen contents of co cultivated algae were higher, while the C:N ratios were much lower. 3. The agar yields of co cultivated algae were much lower than those of mono cultivated algae. Agar yield was found to be negatively correlated to the tissue nitrogen contents, and positively correlated to the C:N ratios. 4. The highest fractional yields obtained from co cultivated algae were extracted with 40% ethanol, while from mono cultivated algae, the highest fractional yields obtained were extracted with distilled water at room temperature.展开更多
在实验室条件下,对比研究了营养盐浓度变化对菊花江蓠(Gracilaria lichenoides)和细基江蓠繁枝变型(G.te-nuistipitata var. liui)的生长、生化组成和生理的影响。结果表明,不同的营养盐浓度变动对2种江蓠的生长、藻体藻红素、叶绿素a...在实验室条件下,对比研究了营养盐浓度变化对菊花江蓠(Gracilaria lichenoides)和细基江蓠繁枝变型(G.te-nuistipitata var. liui)的生长、生化组成和生理的影响。结果表明,不同的营养盐浓度变动对2种江蓠的生长、藻体藻红素、叶绿素a、总碳、总氮含量、硝酸还原酶以及过氧化氢酶活性影响有所不同。菊花江蓠生长在中等浓度(45μmol/L)的营养盐条件下最佳,而细基江蓠繁枝变型的生长反应则依前期环境中营养盐水平不同而有所差异。总体上看,当营养盐浓度由3μmol/L变动为45和150μmol/L时,2种江蓠藻体藻红素、叶绿素a、总碳和总氮含量以及硝酸还原酶的活性均有所提高;而当营养盐浓度由45和150μmol/L变动为3μmol/L时,2种江蓠藻体的上述指标则有所下降。营养盐浓度45和150μmol/L的相互变动对2种江蓠硝酸还原酶的活性影响不大。随着无机氮浓度的逐渐增加,过氧化氢酶的活性呈现显著下降的趋势。当营养盐浓度由3μmol/L向150μmol/L变动时,2种江蓠过氧化氢酶活性显著下降;而营养盐浓度由150μmol/L向3μmol/L变动时,过氧化氢酶活性则有所增强。综合比较表明,细基江蓠繁枝变型更容易受环境中营养盐浓度变动的影响,对环境中营养盐浓度变动的适应能力可能要低于菊花江蓠。展开更多
基金Supported by the 908 Special Program (908-02-04-07)the National Basic Research Program of China (973 Program, No. 2006CB400608)K. C. Wong Magna Fund in Ningbo University
文摘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℃, 30 and 240 μmol/（m^2·s） for G. lichenoides, and 24℃, 20 and 200 μmol/（m^2·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 lamol/（m^2·s） for G. lichenoides （16.26%/d）, and 25.38℃, 21.10, and 229.07 lamol/（m^2·s） for G tenuistipitata （14.83%/d）, respectively.
文摘Gracilaria tenuistipitata varliui Zhang el Xia is cultivated at two different salinities (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.
文摘Gracilaria tenuistipitata var Liui were mono cultivated and co cultivated with Pinctada martensii under high (33) and low (21) salinity conditions in laboratory. The daily growth rate of the alga was determined. Tissue carbon and nitrogen contents, the yield and fractional composition of agar were analyzed. Results showed that: 1. Gracilaria grew better under low salinity conditions, the daily growth rate was twice that under high salinity conditions. Co cultivated algae grew faster than mono cultivated algae under low salinity conditions, the daily growth rate was about 37.6% higher. 2. Compared with mono cultivated algae, tissue nitrogen contents of co cultivated algae were higher, while the C:N ratios were much lower. 3. The agar yields of co cultivated algae were much lower than those of mono cultivated algae. Agar yield was found to be negatively correlated to the tissue nitrogen contents, and positively correlated to the C:N ratios. 4. The highest fractional yields obtained from co cultivated algae were extracted with 40% ethanol, while from mono cultivated algae, the highest fractional yields obtained were extracted with distilled water at room temperature.
文摘在实验室条件下,对比研究了营养盐浓度变化对菊花江蓠(Gracilaria lichenoides)和细基江蓠繁枝变型(G.te-nuistipitata var. liui)的生长、生化组成和生理的影响。结果表明,不同的营养盐浓度变动对2种江蓠的生长、藻体藻红素、叶绿素a、总碳、总氮含量、硝酸还原酶以及过氧化氢酶活性影响有所不同。菊花江蓠生长在中等浓度(45μmol/L)的营养盐条件下最佳,而细基江蓠繁枝变型的生长反应则依前期环境中营养盐水平不同而有所差异。总体上看,当营养盐浓度由3μmol/L变动为45和150μmol/L时,2种江蓠藻体藻红素、叶绿素a、总碳和总氮含量以及硝酸还原酶的活性均有所提高;而当营养盐浓度由45和150μmol/L变动为3μmol/L时,2种江蓠藻体的上述指标则有所下降。营养盐浓度45和150μmol/L的相互变动对2种江蓠硝酸还原酶的活性影响不大。随着无机氮浓度的逐渐增加,过氧化氢酶的活性呈现显著下降的趋势。当营养盐浓度由3μmol/L向150μmol/L变动时,2种江蓠过氧化氢酶活性显著下降;而营养盐浓度由150μmol/L向3μmol/L变动时,过氧化氢酶活性则有所增强。综合比较表明,细基江蓠繁枝变型更容易受环境中营养盐浓度变动的影响,对环境中营养盐浓度变动的适应能力可能要低于菊花江蓠。
