Fungi are an incredibly diverse and nearly ubiquitous group of eukaryotes. Estimates put their numbers higher than 1.6 million species (1). They have been identified traditionally by morphological differences in their sexual or asexual reproductive structures. However, such stru ...
The sensitivity of the polymerase chain reaction (PCR) (1,2), coupled to the specificity afforded by taxon-specific primers allows the analysis of a variety of samples, like minute amounts of cultured organisms (3, 4), or even endosymbionts like the endomycorrhizal fungi present in the roo ...
Among the different methods devised to detect genetic polymorphisms, the analysis of single-strand conformation is simple and yet exquisitely sensitive (1–5). It has been reported that even single base substitution can be detected between DNA fragments ranging in size from 100–450 bp (3). ...
The basic polymerase chain reaction (PCR) (1), which consists of the exponential amplification of DNA fragments between terminal sequences recognized by specific oligonucleotide primers, is a very powerful method but does not satisfy all wishes. The need for sequence information fr ...
Questions regarding species identification, differentiation, and relationships often emerge in biological investigations. One may need to examine the extent of genetic relationships between closely related species for the purposes of resource management or assessment of ...
Leishmaniasis is a parasitic disease that is difficult to diagnose. This IS owing to the low number of parasites observed in clinical samples and the similarity of parasites that cause different clinical symptoms. Previously, culturing was necessary to identify the parasites with tech ...
Many protozoan organisms can be difficult to identify because of morphological similarities between strains or species. This is particularly true in the case of the African trypanosomes (Trypanosoma spp.). These trypanosomes are important medical and veterinary protozoan para ...
The use of molecular protocols has expanded into virtually all branches of plant science in recent years, and crucial to these protocols is the effective isolation of plant nucleic acids in a purified state. Isolation of DNA from plant tissue must be simple, rapid, inexpensive, reproducible, and ...
Onchocerca volvulus is a filarial parasite that is the causative agent of onchocerciasis, or river blindness. Onchocerciasis is one of the leading causes of infectious blindness worldwide (1), and is believed to be one of the most significant causes of social and economic disruption of the rur ...
The detection and identification of the four Plasmodium species that infect humans in samples obtained from the human or the insect hosts, are central for all the studies aimed at understanding the biology, immunology, pathology, and epidemiology of the malaria parasite. Knowledge of the ...
Mosquitoes of the Anopheles gambiae complex include the major vectors of malaria in tropical Africa. Six different sibling species within the complex have been identified on the basis of mating incompatibility (1–3). None of them can be distinguished using morphological characteris ...
Six morphologically indistinguishable but genetically and behaviorally distinct mosquito species comprise the Anopheles gambiae Giles complex (1,2). All occur in Africa and in some localities three and possibly even four of these species occur in sympatry. The two most widespread s ...
With the discovery of bacterial “restriction endonucleases” (1), it became possible to fractionate the long DNA molecule, so that specific regions could be analyzed. These enzymes cut DNA at specific short sequences, commonly consisting of four to six nucleotides (2). DNA fragments of disc ...
Anopheles farauti complex has been shown to be composed of several species, numbered A. farauti no. 1 through A. farauti no. 6 (1–4). Members of this complex are regarded as potential vectors for malarial parasites (5). These species are morphologically indistinguishable. Three methods based ...
The parasitic Hymenoptera represent a group of insects that is both taxonomically and biologically poorly defined, despite the fact that members of the group are the premier agents in successful programs for the biological control of phytophagous insect pests. The vast majority of Hymen ...
The identification of insects and other invertebrates is often extremely difficult if not impossible to achieve when attempted by traditional methods. There are several reasons why these difficulties are encountered. They may be owing to the presence of species complexes where indiv ...
The isolation of DNA from insects normally does not present any specific problems. Therefore, any one of a multitude of techniques used for isolation of DNA from other organisms will usually work with insect tissue. Our intention in this chapter is to present methods that have worked well in our labo ...
Isolation of DNA from surrounding tissues is a crucial initial step in any molecular biological investigation of organisms. DNA in cells is complexed with numerous proteins and exists in an environment saturated with a whole host of other biomolecules. This chapter presents two alternat ...
The purpose of this chapter is to illustrate some techniques exploiting the properties of viral nucleic acids by which plant viruses can be identified and the diseases they induce diagnosed. These methods are basically the same as those used in other fields of biology and, therefore, some detai ...
Two techniques have been described that use the polymerase chain reaction (PCR) to amplify many arbitrary regions of a genome simultaneously. Regions amplified by these techniques are generally polymorphic among closely related species and are beginning to be used in molecular taxon ...