共查询到20条相似文献，搜索用时 109 毫秒
1.
芦荟叶片愈伤组织诱导的研究 总被引：1，自引：0，他引：1
以中华芦荟、库拉索芦荟和木立芦荟的叶片为外植体进行组织培养。结果表明：三种芦荟均可以在特定的培养基中形成愈伤组织。中华芦荟愈伤组织的诱导最佳培养基为：MS 6-BA0.2mg／L 2，4-D0．5mg／L；库拉索芦荟愈伤组织的诱导最佳培养基为：MS 6-BA1.0mg／L 2，4-D1．0mg／L；木立芦荟愈伤组织的诱导最佳培养基为：MS 6-BA2．0mg／L 2，4-D1．5mg／L。 相似文献
2.
3.
4.
5.
6.
三种芦荟的区别及其遗传差异 总被引：3，自引：0，他引：3
对上农大叶芦荟、木立芦荟、库拉索芦荟三个具有产业发展前景的芦荟进行观察，比较它们之间的形态和生理差异，用三种芦荟试管苗的根进行根尖细胞染色体检查，发现三种芦荟的根尖细胞染色体2n均等于14，由四对长染色体和三对短染色体组成，属二型性核型。三种芦荟在染色体在相对长度和着丝点类型上存在差异。对三种芦荟的遗传进化作了探讨。 相似文献
7.
8.
9.
10.
11.
Zhao JH Zhang JS Wang Y Wang RG Wu C Fan LJ Ren XL 《Journal of Zhejiang University. Science. B》2011,12(11):935-942
DNA methylation plays an important role in the epigenetic regulation of gene expression during plant growth, development,
and polyploidization. However, there is still no distinct evidence in tobacco regarding the distribution of the methylation
pattern and whether it contributes to qualitative characteristics. We studied the levels and patterns of methylation polymorphism
at CCGG sites in 48 accessions of allotetraploid flue-cured tobacco, Nicotiana tabacum, using a methylation-sensitive amplified polymorphism (MSAP) technique. The results showed that methylation existed at a
high level among tobacco accessions, among which 49.3% sites were methylated and 69.9% allelic sites were polymorphic. A cluster
analysis revealed distinct patterns of geography-specific groups. In addition, three polymorphic sites significantly related
to tobacco mosaic virus (TMV) resistance were explored. This suggests that tobacco breeders should pay more attention to epigenetic
traits. 相似文献
12.
Berman BA Eckhardt EA Kleiger HB Wong G Lipton DS Bastani R Barkin S 《American annals of the deaf》2000,145(3):245-255
Formidable barriers hinder use of standard data collection methods among deaf youth. Culturally and linguistically sensitive data collection strategies are needed to identify the unmet health and programming needs of this population. Unfortunately, researchers often fail to describe the issues involved in developing such targeted methods. The authors describe development of a culturally appropriate data collection instrument for a study of tobacco-related knowledge, attitudes, and practices among deaf youth. The instrument uses interactive multimedia technology to administer a questionnaire translated into the primary languages used by the Deaf. The procedures taken to accommodate this technology to these languages and to Deaf culture are described. This process yielded useful insights with respect to data collection not only among the Deaf, but among other frequently overlooked and underserved populations as well. 相似文献
13.
植物抗虫基因工程是解决农业生产中虫害问题的一种重要手段，利用抗虫基因使植物获得抗虫性已经得到了实际应用，在可经利用的抗虫基因中，植物外源凝集素基因是一个重要方面，植物外源凝集素是一组广泛存在于植组织中的蛋白质成分，现已发现多种植物外源凝集素对同翅目，鞘翅目，鳞翅目害虫有抗杀作用，菊芋外源凝集素是一种新发现的植物外源凝集素，本文将其置于CaMV35S组成型启动子和Tnos终止了的控制下，构建了用于转化烟草的植物表达载体，转化烟草并获得了转基因烟草，以期下一步对菊芋外源凝集素的抗虫性做出评估。 相似文献
14.
15.
利用携带植物表达载体质粒pCambia2301的农杆菌菌株,通过注射渗透法对烟草叶片进行感染转化,组织化学染色检测GUS报告基因瞬时表达的结果表明,在O.D.600值为0.4～0.8范围内的菌液浓度不影响转化效果,感染时间72 h以上可使瞬时表达的阳性检出率达到100%,农杆菌菌株EHA105比LBA4404表现出更强的转化活性. 相似文献
16.
本文介绍了卷烟厂风力送丝系统中影响烟丝造碎率的两个主要因素：输送风速与料气比。基于目前大多数卷烟厂风送系统不具备调速功能或者调速效果欠佳,造成风速过高、烟丝造碎高、烟尘增加、能耗大等问题,提出了风速平衡控制的设计方法与调节手段,有效控制烟丝输送风速在18-22m/s范围内,降低烟丝造碎,系统运行稳定。 相似文献
17.
Garry Trudeau's comic strip Doonesbury launched repeated attacks against the tobacco industry. These messages argued that tobacco was a health hazard and that cigarettes are addictive, they ridiculed the tobacco industry's campaign for smokers’ rights, and they charged that cigarettes are marketed to our nation's youth. This series of attacks culminated in the “Smoke Starters’ Coupon” strip, which promised free cigarettes to those who returned the coupon if they were under‐aged and provided the address of the industry lobby, the Tobacco Institute. The Institute responded with a brochure ("Smoking and Young People: Where the Tobacco Industry Stands") sent to the hundreds of people who mailed in coupons. This essay applies the theory of image restoration discourse to this controversy, concluding that Doonesbury's attack was powerful and the industry's response ill‐conceived. 相似文献
18.
龙岩烟草气象防灾体系的现状及对策 总被引：6，自引：0，他引：6
龙岩市是全国优质烤烟基地之一,烟草行业发展与气象有着密切关系。通过分析研究龙岩烟草气象防灾减灾体系现状以及取得的成效与不足,减少并避免灾害性天气对烟草生产的影响,以确保烟叶生产可持续协调健康发展。 相似文献
19.
洪火奇 《闽西职业技术学院学报》2004,6(3):114-116
通过田间试验探讨不同镁肥对烤烟产量和品质的影响。研究结果表明福建省烟区土壤增施镁肥可提高烤烟产量14.28～19.19%,增加上等烟叶数量8.77～12.75%,每667m2增加经济效益181.88～242.47元。以施用氢氧化镁的增产效果最好,氧化镁和硫酸镁次之。 相似文献
20.
为解决常规控制图在叶丝干燥出口含水率监控中大量虚发警报,造成控制图监控失效的问题,采用时间序列模型对叶丝干燥出口数据进行拟合分析,使用残差控制图对含水率进行监控,降低了控制图的误警报率,提高了控制图在出口含水率控制中的应用效果. 相似文献