Biotic agents

Among biotic agents fungi that produce toxins are an important and widespread threat that can contaminate cereals. 

This paper will consider the basis for the principles of disease control by non-fungicidal compounds, the current research results, and the prospects for their future use. Induction of disease resistance by biotic agents will also be included because non-fungicidal substances might be involved in this process. 

Biotic Agents. It is well-established that treatment of plants with virulent or avirulent forms of a pathogen, or with a non-pathogen, may induce the formation of fungitoxic compounds (phytoalexins) which prevent or retard subsequent infection by a pathogen. The phytoalexins are formed at the site of inoculation and are not transported to other plant parts. 

In addition to this local resistance, biotic agents may induce systemic resistance. Infection of the first true leaf of cucumber plants with Colletotrichum lagenarium immunized other aerial plant parts against infection by lagenarium, Cladosporium cucumerinum and Pseudomonas lachrymans (16). Bean plants appeared systemically protected against Colletotrichum lindemuthlanum when the first leaf had been inoculated with a non-pathogenic race of this fungus or with... 

The study of factors or signals produced upon treatment of a plant part with a biotic agent, and which cause metabolic changes related to disease resistance at other sites, is of particular interest. Elucidation of their nature might provide new clues to manipulate the relationship between plant and parasite. 

The limited ranges of bond types present in the POPs are generally relatively resistant to attack by abiotic or biotic agents in the environment. As a result environmental degradation proceeds at a relatively slow rate. Most compounds in this group persist for long periods in the environment and often exhibit half-lives of many years as illustrated by the data in Table 17.1. 

General Occurrence of Resistance Induced by Biotic Agents... 

When used without preparative procedures, the most commonly used techniques are typically unable to provide quantitation of individual adducts and chemical characterization of a specific adduct. This is because humans are exposed to complex mixtures of chemical carcinogens, and human DNA will contain multiple DNA adducts induced by different xeno-biotic agents. The development of preparative strategies for sample purification that can be applied... 

Why do brown or type III sorghums have more resistance to sprouting, molds, birds, and other biotic agents What is the basis of identification of tannin sorghums using chlorine solution ... 

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