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[目的]探索芦荟的离体快繁技术,为芦荟的组织培养提供试验依据。[方法]以盆栽中华芦荟的嫩茎尖为外植体,MS为基本培养基,不同的增殖阶段添加不同的植物激素进行离体快繁试验。[结果]培养30 d后,3瓶被污染,4瓶不长愈伤组织,13瓶在芽基部产生圆球状浅黄色的愈伤组织。在诱导芽分化约20 d后,2瓶被污染,11瓶开始芽点分化。3.00 mg/L 6-BA的处理效果最佳。诱导生根11 d后,1瓶被污染,2瓶出现叶子干焦的现象,17瓶长势良好。中华芦荟愈伤组织诱导的适宜培养基为MS+6-BA 2.50 mg/L+NAA0.15 mg/L,诱导率为60%;丛生芽分化及继代的适宜培养基为MS+6-BA 3.00 mg/L+NAA 0.10 mg/L,诱导率为85%;生根的适宜培养基为MS+6-BA 0.30~0.50 mg/L+IBA 0.20 mg/L+活性炭0.5%。[结论]该研究为芦荟的快繁提供了初步的理论依据。 相似文献
93.
Apoptosis is proposed to be a major cause of death in shrimp viral infections. From our previous study, an apoptosis-related gene, Pm-Alix, was identified from the black tiger shrimp. Its expression was high in defence-related tissues including haemocytes and the lymphoid organ. To clarify its possible role in shrimp, we used Pm-Alix as bait in a yeast two-hybrid analysis to search for Alix interacting proteins in shrimp. Two cDNA sequences discovered had homology to a predicted ubiquitin C of the purple sea urchin, Strongylocentrotus purpuratus, and to a guanylyl cyclase of the red swamp crayfish, Procambarus clarkii. In vitro pull-down assays confirmed positive interaction between Pm-Alix and both proteins. Tissue distribution analysis revealed that Pm-Alix and the two binding partners were widely expressed in various tissues but more highly expressed in haemocytes. However, no significant positive or negative correlation was found in the expression of these genes as shrimp approached morbidity and death after challenge with white spot syndrome virus. Thus, the results suggested that Alix and its interacting partners did not play a direct role related to shrimp death. 相似文献
94.
通过对凤城市郊区北五味子园杂草种群分布情况的调查和实施不同覆盖措施清除杂草试验,结果表明:凤城市郊区五味子园杂草具有鲜明的季节特性和杂草分布不均匀特性,杂草滋生数量较大,对五味子植株生产影响较大;杂草主要通过草籽和串根繁殖;不同覆盖措施间控制杂草的效果差异极显著,以覆双层黑地膜取得的效果最好,杂草比对照减少99.80%。采取双层黑地膜覆盖技术是有效控制五味子园杂草滋生蔓延的最佳措施,能够达到彻底控制杂草的目的。 相似文献
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96.
采用1.95×10-4mol.L-1的KK-42溶液浸润处理南美白对虾(Penaeus vannamei)幼虾(体长为4.2~5.0cm),从组织细胞学水平对分泌蜕皮激素的Y-器官结构进行初步研究,观察KK-42处理后幼虾Y-器官的形态结构变化。结果表明,伴随动物的生长,Y-器官腺细胞条索变粗,腺细胞核增大。KK-42处理后腺细胞核的结构、大小未见显著变化,腺细胞索的宽度明显高于同一时期对照组。 相似文献
97.
Two kinds of specific chicken egg yolk immunoglobulins (IgYs), IgY‐WSSV and IgY‐VP28, were, respectively, raised against the 2 mM binary ethylenimine (BEI)‐inactivated white spot syndrome virus (WSSV) and a principal envelope protein VP28. The activity of purified specific IgYs was stable under the conditions of 20–70 °C, pH 3.0–10.0 and 0–700 g L?1 sucrose solution. In the neutralization assay, these high‐affinity IgY antibodies can specifically bind with the virus particles to protect shrimp (Fenneropenaeus chinensis) against WSSV infection. After oral delivery for 20 days, the IgY‐WSSV exerted a higher protection effect (RPS: 71.5%) than IgY‐VP28 (RPS: 63.7%). Moreover, an increase in RPS (79.2%) was found on addition of IgY‐WSSV:VP28 (0.1% IgY‐VP28 plus 0.2% IgY‐WSSV). This may indicate that neutralization of WSSV refers to the multiple‐hit model. By time‐course study of the levels of the specific IgYs in vivo, the data showed that the titre was enhanced to a relatively high level (P/N=8.35±0.45) at 3 days post administration, declined slightly (P/N=7.13±1.01) at 7 days post administration and then remained stable for further investigation. The stable antibody level potentially contributes towards blocking a large number of WSSV particles from entering and infecting on the major tissues at the early and late stages after challenge in shrimp. 相似文献
98.
Srinivas Somnath Pai Abdulaziz Anas Natamai Subramaniam Jayaprakash Prabhakaran Priyaja Balachandran Sreelakshmi Radhakrishnan Preetha Rosamma Philip Ambat Mohandas Isaac Sarogeni Bright Singh 《Aquaculture Research》2010,41(6):847-860
This study shows that the disease resistance and survival rate of Penaeus monodon in a larval rearing systems can be enhanced by supplementing with antagonistic or non‐antagonistic probiotics. The antagonistic mode of action of Pseudomonas MCCB 102 and MCCB 103 against vibrios was demonstrated in larval mesocosm with cultures having sufficient concentration of antagonistic compounds in their culture supernatant. Investigations on the antagonistic properties of Bacillus MCCB 101, Pseudomonas MCCB 102 and MCCB 103 and Arthrobacter MCCB 104 against Vibrio harveyi MCCB 111 under in vitro conditions revealed that Pseudomonas MCCB 102 and MCCB 103 were inhibitory to the pathogen. These inhibitory properties were further confirmed in the larval rearing systems of P. monodon. All these four probionts significantly improved larval survival in long‐term treatments as well as when challenged with a pathogenic strain of V. harveyi MCCB 111. We could demonstrate that Pseudomonas MCCB 102 and MCCB 103 accorded disease resistance and a higher survival rate in P. monodon larval rearing systems through active antagonism of vibrios, whereas Bacillus MCCB 101 and Arthrobacter MCCB 104 functioned as probiotics through immunostimulatory and digestive enzyme‐supporting modes of action. 相似文献
99.
100.
该研究通过肉眼观察、镜检,进行干露、饥饿、盐度突降、福尔马林等抗性试验,并采用病毒检测等方法,以期建立评估斑节对虾(Penaeus monodon)虾苗活力和质量标准。结果表明,斑节对虾健康虾苗具有趋光性、集群性,体表光洁,肌肉透亮,肠胃食物充盈等特性。测试虾苗干露时间以15min为宜,健康虾苗干露后能立即恢复活力,而病弱虾苗多出现死亡、昏迷现象;虾苗的成活率随饥饿时间的延长而降低,随福尔马林浓度升高和时间延长而降低,随盐度突降幅度增加而降低。健康虾苗能忍受100~200μL·L^-1福尔马林溶液30min,成活率近100%;在盐度20~30下虾苗的成活情况较好,而其在淡水中仅能存活1h。对虾苗进行病毒检测,可以避免养殖中因虾苗携带病毒而可能导致的病毒性疾病的暴发。 相似文献