植物学技术

Leaf disk transformation of tobacco is a very simple and robust method. It is used with success in many laboratories. The protocol presented here is a simplified version of that of Horsch et al. (1). Basically, it consists of immersing the leaf disks in a liquid culture of Agrobacterium carrying the chos ...

Numerous techniques have been developed to transfer genes into plants to create genetically engineered crops that can tolerate environmental stresses, and to improve productivity and quality. The search for easier, more efficient techniques to transfer genes continues because ...

An important step in the analysis of gene action is to determine the spatial and temporal regulation of gene expression. The patterns of gene expression can provide clues to the function of genes and facilitate the mapping of qualitative changes in steady state mRNA levels. In situ hybridization ...

The regulation of biotechnology within the member states of the European Community has developed very significantly over the last 3 yr, and a comprehensive body of legislation, guidance notes, and codes of practice have appeared in the United Kingdom in particular. The recent incident at Bir ...

Agrobacterium spp. are widely used to transform new genes into plant tissue. Transferring useful genes into bacteria in order to transform them into the target plant is an essential part of the process, which can be achieved by electroporation.

Agrobacteria are soil living Gram-negative rod-shaped bacteria. The genus includes two well-studied phytopathogenic bacteria, Agrobacterium tumefaciens and A. rhizogenes. Their ability to cause disease is associated with the presence of a large (about 200 kb) plasmid. The plasm ...

Directed movement in response to chemical attractants is of crucial importance to Agrobacterium tumefaciens. Motility is a determinant of rhizosphere competence (1), and chemotaxis a conditional requirement for virulence (2,3). A. tumefaciens is attracted toward a variety of sug ...

Expression of the virulence genes of Agrobacterium tumefaciens occurs in acidic media containing sugars and certain phenolics secreted at plant wounds. In some strains of A. tumefaciens, exposure to these inducing conditions leads to inhibition of bacterial growth, which can then be fo ...

Living organisms have been continuously evolving by assimilating new genetic material from the environment. However, this progress is very slow and often limited to transfer of genetic materials among closely related species. Recent developments in molecular biology and gene tra ...

Reliable and efficient methods of transferring cloned genes into plants are essential for engineering crops with desired traits. The Gram-negative soil bacteria, Agrobacterium tumefaciens and A. rhizogenes, are natural genetic engineers, capable of transforming a range of dico ...

Although a number of protocols are available for the regeneration of oilseed rape protoplasts (1–4), there are almost no reports of successful Agrobacterium tumefaciens-mediated transformation of protoplasts resulting in transgenic plants. Plant regeneration from protop ...

The commercial importance of oilseed rape (Brassica nupus L.) makes it desirable to have an efficient transformation protocol for practical applications. With the exception of a few reports, transformation experiments with B. napus using Agrobacterium tumefaciens yielding tra ...

Since the first reports of tobacco transformation experiments in 1983, a number of fundamental processes, such as gene expression, cell metabolism, or plant development, are being studied using gene transfer experiments. The spectrum of plant species amenable to transformation is co ...

The hordeivirus group of RNA viruses contains three members: barley stripe mosaic virus (BSMV), poa semilatent virus (PSLV), and lychnis ringspot virus (LRSV), with anthoxanthum latent bleaching virus (ALBV) considered to be a possible fourth member (1). Hordeiviruses have a diverse host ...

The Rhabdoviridae family consists of a large number of nonsegmented negative-strand RNA viruses. As a group, the rhabdoviruses cause many serious plant and animal diseases that have detrimental effects on agricultural productivity, public health, and wildlife populations. The me ...

Plant reoviruses are classified in three genera in the family Reoviridae: Phytoreovirus, Fijivirus, and Oryzavirus. Fifteen viruses, including possible members, are described (1). With two exceptions, all of them infect plants in gramineae. They possess 10–12 segmented double-str ...

Much has been written on the possible risks arising from the use of virus-resistant transgenic crop plants but little of the benefits that might result. Many of the potential benefits are self-evident and relate to improved disease control, but others are less so and arise from such indirect effec ...

Recent advances in the understanding of the molecular mechanisms of how viruses function and how they interact with plants have led to the development of various nonconventional approaches to protection of plants against viruses. Many of these approaches involve the introduction of v ...

Viral diseases cause significant losses to almost all crops throughout the world. Infections with plant viruses can either cause direct yield losses or lead to unacceptable levels of postharvest damage to the crops. Besides measures to limit the virus incidence, the ultimate way to minimi ...

Members of the caulimovirus group (1) each have a circular double-stranded DNA genome of approx 8 kbp that is encapsidated in a spherical, naked nucleocapsid of approx 50 nm diameter (Fig. 1). Caulimoviruses characteristically produce subcellular inclusion bodies in infected tissues t ...