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131.
麝香百合组培快繁技术初步研究   总被引:13,自引:0,他引:13  
采用随机区组试验方法,以MS为基本培养基,对百合叶片进行了不同浓度的NAA和6-BA处理试验,探讨生长激素对百合成苗和增殖的作用,结果表明,以NAA0.1mg/L处理的成苗率和结鳞率最高,小苗长势最好;以6-BA2.0mg/L NAA0.2mg/L处理的增殖系数最高。  相似文献   
132.
To investigate the effects and mechanisms of the benzimidazole carbamate and benmidine drugs on Cysticerci cellulosae and choose effective drugs on Cysticerci cellulosae, the membrane metabolism of Cysticerci cellulosae in vitro was tested after three kinds of drugs which were used respectively. The indexes included the contents of lipids, the contents of SA and the changes of the membrane fluidity. The results showed that oxfendazole could inhibit the membrane metabolism of immature and mature Cysticerci cellulosae in vitro, and albendazole only inhibited the mature one, while thibendimidine neither acted on the immature nor mature one.  相似文献   
133.
菊花花瓣培养不定芽的形成及植株再生   总被引:2,自引:0,他引:2  
一次培养诱导菊花花瓣形成不定芽,以 MS+IAA10mg/L+6BA10mg/L+KT0.1mg/L 培养基为好。培养45天的芽分化率为68%~80%;平均每个发芽块产生的芽数是4.7~8.6个。用花瓣的基部组织进行培养,芽分化率(95%)显著高于中部(70%)和上部(60%)。不同接种方向对菊花花瓣不定芽形成无显著影响。菊花花瓣组织培养的效果在不同品种间差异极显著,形成不定芽能力的强弱顺序为白色>黄色>红色>粉红色。  相似文献   
134.
This study investigated the growth performance and nutritional composition of scale artificially cultured cuttlefish Sepia pharaonis. Juveniles were cultured in an open‐culturing cement pool system for 120 days. The body weight increased from 10.21 ± 1.44 g to 570.71 ± 126.32 g from 50 days old to 170 days old, and the average growth rate was 4.67%. The proximate, amino acid and fatty acid compositions of S. pharaonis muscles were analysed every 40 days to compare the quality. The cultured S. pharaonis were rich in essential amino acids (EAAs), functional amino acids (FAAs), docosahexaenoic acid (DHA) and polyunsaturated fatty acids (PUFAs), which accounted for 32%, 46%, 28% and 54% (dry weight) respectively. Total amino acids (TAAs) and EAAs exhibited a clear distinction between ages, and significant differences were observed among the levels of individual amino acids, including Pro, Ala, Asp and Lys, which were significantly higher at 130–170 days old than at 50 days old (< 0.05). Although the total saturated fatty acids, monounsaturated fatty acids and PUFAs were statistically similar between ages, C17:0, C22:6 n‐3 and PUFAs were higher at 130–170 days old than at 50 days old (< 0.05). The results indicate that large‐scale artificial culture of S. pharaonis can be achieved under the conditions of a cement pool. This study also provides new information regarding the growth performance and nutritional composition of cultured S. pharaonis, which will contribute to the development of aquaculture practices for this species.  相似文献   
135.
对小型水库的养鱼模式,网箱配置,水库施肥等高产技术进行了综合研究。1992年,试验水库41座,面积351公顷,总产成鱼1283.6t,平均每公顷产3657kg,净产3310.5kg,比开发前提高4.27倍;每公顷纯利8804.25元,投入产出比1:1.92。1993年6月专家鉴定认为,本研究居国内同类技术开发的领先水平。  相似文献   
136.
放养密度和微生态制剂对施氏鲟养殖水质的影响   总被引:1,自引:0,他引:1  
将初始体质量(54.86±10.19)g的施氏鲟Acipenser schrenckii饲养在面积16m~2(4m×4m)、水深1.7~1.9m的陆基围隔中,密度分别为2 000尾/667m~2、3 000尾/667m~2、4 000尾/667m~2和5 000尾/667m~2,每个密度组均设3个平行,常规饲养,混合泼洒光合细菌、枯草芽孢杆菌和乳酸菌,第一次泼洒量为光合细菌50m L、枯草芽孢杆菌50g和乳酸菌50g,之后每5d泼洒第一次量的1/2,研究微生态制剂对静水土养殖池塘水质的影响。结果显示:水体中溶解氧量随养殖密度的增加逐渐降低(P0.05),氨氮、亚硝酸盐浓度随养殖密度的增加逐渐升高(P0.05)。在使用微孔增氧的条件下,泼洒微生态制剂对溶解氧量和氨氮浓度的影响不显著(P0.05),但显著降低了水体亚硝酸盐浓度(P0.05),显著增加了浮游动物生物量(P0.05)。  相似文献   
137.
Soybean molasses was evaluated as a partial replacement for sugarcane molasses as a carbon source for biofloc development in the superintensive culture of Pacific white shrimp (Litopenaeus vannamei). A 50‐day study was conducted with juvenile (3.2 g) shrimp stocked in 16 800 L tanks at a stocking density of 250 shrimp m?3. Control of total ammonia concentration was performed by the addition of combined mixtures of soybean and sugarcane molasses to the culture water. Three different molasses treatments were evaluated using different soybean‐to‐sugarcane molasses ratios: 15–85%, 38–62% and 60–40% respectively. The control group was treated only with sugarcane molasses. Water quality, chlorophyll a concentration, heterotrophic bacterial load, Vibrio spp. concentration and zootechnical indexes were all evaluated. Total ammonia concentration was controlled by heterotrophic and chemotrophic pathways. Biofloc formation, as quantified by measuring the total suspended solids, was not altered. The Vibrio spp. concentration showed a significant reduction in treatments with soybean‐to‐sugarcane molasses ratios of 38–62% and 60–40%. All combined mixtures of soybean and sugarcane molasses could maintain water quality and productivity in the superintensive culture of L. vannamei using the biofloc system. Thus, the potential use of a residue from agroindustry as a carbon source in a biofloc culture is demonstrated.  相似文献   
138.
The aim of this study was to compare two rearing systems for freshwater prawn Macrobrachium rosenbergii: one with use of a recirculating aquaculture system with biofilters (RAS) and another with use of microbial flocs (F). Thirty postlarvae of freshwater prawn with an initial average weight of 0.13 ± 0.05 g were randomly stocked in six experimental units with 0.20 m² and volume of 50 L. The experiment lasted thirty days. Dissolved oxygen, temperature and pH were monitored daily; ammonia concentration was determined three times per week; nitrite concentration, alkalinity and hardness were measured weekly. For the formation of microbial floc, molasses was used to keep the ammonia concentrations within safe levels for prawn farming. The variables of water quality remained within the suitable range for the production of the species, except for ammonia concentrations at the F treatment, which exceeded the safe levels. At the end of the experiment, the following parameters were evaluated: survival, specific growth rate, weight gain and feed conversion rate. Differences were found only in feed conversion rate with better values on RAS treatment. The microorganisms present in the RAS and F treatment were also evaluated. The densities of rotifers, amoebas and total bacteria were higher at the F treatment although the same organisms were found at the RAS treatment. The results of this study showed the possibility of rearing M. rosenbergii in biofloc system technology.  相似文献   
139.
The major objective of this study was to introduce a newly designed recirculating aquaculture system (RAS) for oyster (Crassostrea angulata) larval culture. The system includes a culture tank, a suspended circular inlet‐pipe, an upwelling aeration pipe, combined “banjo” sieves and a bioreactor chamber containing microalgae life keeping installation. The system was designed to resolve three problems: (i) stranding of larvae caused by water level changes and aeration, (ii) physical clogging of the screens and also (iii) deterioration of diet microalgae. The culture tank, “banjo” sieve size, water flow rate and light intensity for maintaining microalgae activity were all designed according to the pattern of larval movement and feeding behaviour. Results of this study showed the best average SGR for larval length was 6.36%/d (9.5 μm/d) and survival rate was 80%, with initial rearing density of 50 larvae/ml, indicating the problems above were fully resolved. Consequently, the system is fit for larval culture in mass production of oysters.  相似文献   
140.
2008年4月初在广东省饶平县对2006年5月人工孵化和培育的2龄条石鲷( Oplegnathus fasciatus)成熟亲鱼进行激素诱导,研究和观察条石鲷亲鱼初次性成熟的繁殖生物学。结果显示,在南海区全人工养殖的条石鲷亲鱼初次性成熟年龄为2龄,成熟亲鱼的最小型为全长245 mm、体质量610 g,最大个体为全长300 mm、体质量1450 g;产卵季节为4月10日~7月15日,产卵盛期为4月中旬至6月下旬;为升温产卵型鱼类,产卵温度为20.0~28.8℃,适宜的产卵温度为20.7~27.6℃;雌、雄亲鱼发育同步,个体大小和成熟年龄差别不大;雌鱼属于一年一次分批产卵类型,产卵期超过3个月;24尾初次性成熟雌性亲鱼的总产卵量为3180.0×104粒,日最高产卵量为341.5×104粒;其产卵量和受精卵质量与水温的变化关系密切,受精卵的浮卵率随温度的变化而变化,在水温相对衡定时,浮卵率相对稳定并维持在80%~95%的较高水平;受精卵平均卵径为(0.860±0.023)mm,油球径为(0.191±0.009)mm。  相似文献   
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