j Uch has been learned about the behaviour of the microbes that cause Section in hospitals and this epidemiological knowledge has helped to reduce Joss-infection by organisms from outside the patient. Thus, for example, ^vances have been made in preventing airborne infection in operating eatres and in excluding extraneous bacteria from surgical wounds, from abies' skin, and from the urinary tra...

For more than 200 years, the plant hormone salicylic acid (SA) has been studied for its medicinal use in humans. However, its extensive signaling role in plants, particularly in defense against pathogens, has only become evident during the past 20 years. This review surveys how SA in plants regulates both local disease resistance mechanisms, including host cell death and defense gene expression...

There is increasing evidence that chronic, subclinical exposure to certain environmental pollutants may upset immune responsiveness and alter susceptibility of animals to infectious agents. Environmental chemicals or drugs may affect diverse aspects of the immune system, leading to immunosuppression, immunopotentiation, hypersensitivity or perturbed innate host resistance. A variety of infectio...

a recently published article describing the draft genome of erwiniamallotivora bt-mardi (1), the causal pathogen of papaya dieback infection in peninsular malaysia, hassignificant potential to overcome and reduce the effect of this vulnerable crop (2). the authors found that the draft genome sequenceis approximately 4824 kbp and the g+c content of the genomewas 52-54%, which is very similarto t...

Plant breeding for disease resistance is crucial to sustain global crop production. For decades, plant breeders and researchers have extensively used host plant resistance genes (R-genes) to develop disease resistant cultivars. However, the general instability of R-genes in crop cultivars when challenged with diverse pathogen populations emphasizes the need for more stable means of resistance. ...

Resistance to a number of nematodes is present in varieties of temperate and tropical cereals. The occurrence, nature, and inheritance of varietal resistance in cereals is reviewed. Evaluation of the practical significance of nematode resistance in a particular host-nematode combination is discussed in relation to host efficiency, host sensitivity, genetic control of resistance, and presence of...

Organisms that can resist parasitic infection often have lower fitness in the absence of parasites. These costs of resistance can mediate host evolution during parasite epidemics. For example, large epidemics will select for increased host resistance. In contrast, small epidemics (or no disease) can select for increased host susceptibility when costly resistance allows more susceptible hosts to...