植物生理

Gossypol is a polyphenolic aldehyde (Fig. 1) that is an antioxidant and polymerization inhibitor. It is toxic to monogastric animals; pigs and rabbits are the most sensitive, whereas poultry are relatively more tolerant. The general symptoms of gossypol toxicity are constipation, depr ...

Tannins are polyphenolic compounds that are broadly categorized into two major groups: (1) hydrolyzable tannins, consisting of a central core of carbohydrate to which phenolic carboxylic acids are bound by ester linkage (Fig. 1); and (2) condensed tannins, or proanthocyanidins, consi ...

Cyanide (hydrogen cyanide, HCN) in trace amounts is widespread in the plant kingdom and occurs mainly in the form of cyanogenic glucosides (also called as cyanogens). Cyanogens are glycosides of sugar and cyanide-containing aglycon. These generally taste bitter. Relatively high conc ...

Glucosinolates, a group of plant thioglucosides, occur naturally in many plant species. These consist of a β-thioglucose moiety, a sulfonated oxime moiety, and a variable side chain derived from an amino acid. More than 120 different side chains have been described, although glucosinolat ...

The nonprotein amino acid, 3,4-dihydroxyphenylalanine (L-DOPA) (Fig. 1) is present in high concentrations (about 3–6%) in Mucuna spp. The in vitro addition of L-DOPA to the red blood cells from individuals deficient in glucose 6-phosphate dehydrogenase decrease the glutathione content ...

The term phorbol is loosely used to describe a family of naturally occurring compounds referred to as tiglian diterpenes. These are widely distributed in the plant species of the families Euphorbiaceae and Thymelaeaceae. This chapter describes a method for determination of phorbol est ...

Saponins comprise a large family of structurally related compounds containing a steroid or triterpenoid aglycone (sapogenin) linked to one or more oligosaccharide moieties by glycosidic linkage (Fig. 1). The carbohydrate moiety consists of pentoses, hexoses, or uronic acids. The p ...

Alkaloids are a diverse group of organic bases containing secondary, tertiary, or cyclic amines. Some 5500 alkaloids are known, comprising the largest single class of secondary plant substances. There is no one definition of the term alkaloid, which is completely satisfactory, but alkal ...

Among the many factors that have been implicated as having an adverse effect on the nutritional value of proteins is a class of proteins, known as protease inhibitors, that has the ability to inhibit the proteolytic activity of proteases of diverse origin. The protease inhibitors that have been i ...

Similar to the trypsin inhibitor, the chymotrypsin inhibitor also decreases protein degradability in the intestine, resulting in lower availability of amino acids and peptides for production purposes. This adversely affects growth and other productive responses. This inhibi ...

α-Amylase inhibitors are heat-labile proteins that are active against salivary, pancreatic, bacterial, or insect α-amylases. Two thirds of the albumin fractions of wheat are composed of multiple protein components capable of inhibiting α-amylases of diverse origin. Three major gr ...

A variety of techniques have been used to examine plant viral genomes, the functions of virus-encoded proteins, plant responses induced by virus infection and plant–virus interactions. This overview considers these technologies and how they have been used to identify novel viral and pl ...

Coat proteins (CPs) of all plant viruses have an early function in disassembly of parental virus and a late function in assembly of progeny virus. Depending on the virus, however, CPs may play a role in many steps of the infection cycle in between these early and late functions. It has been shown that CPs can play a ...

Plant viruses spread from the initially infected cells to the rest of the plant in several distinct stages. First, the virus (in the form of virions or nucleic acid protein complexes) moves intracellularly from the sites of replication to plasmodesmata (PD, plant-specific intercellular m ...

Identification of the roles of replication factors represents one of the major frontiers in current virus research. Among plant viruses, the positive-stranded (+) RNA viruses are the largest group and the most widespread. The central step in the infection cycles of (+) RNA viruses is RNA replica ...

RNA silencing suppressors, developed by plant viruses, are potent arms in the arm race between plant and invading viruses. In higher plants, these proteins efficiently inhibit RNA silencing, which has evolved to defend plants against viral infection in addition to regulation of gene expr ...

The technique described was developed for the separation of begomovirus DNA. DNA products resulting from and during geminiviral replication are characterized by the application of strand-specific separation and identification by strand-specific DNA probing of Southern bl ...

Most phytoviruses rely on vectors for their spread and survival. Although a great variety of virus vectors have been described, there are relatively few different mechanisms mediating virus transmission by vectors: virions can either be internalized into vector cells where replica ...

Viroids, as a consequence of not encoding any protein, are extremely dependent on their hosts. Replication of these minimal genomes, composed exclusively by a circular RNA of 246–401 nt, occurs in the nucleus (family Pospiviroidae) or in the chloroplast (family Avsunviroidae) by an RNA-bas ...

The Begomovirus genus is the largest genus of the Geminiviridae family and comprises the whitefly transmitted geminiviruses that infect dicotyledonous plants. They can be either mono or bipartite. In this chapter, we describe the cloning of begomovirus replication modules and the su ...