Glutamine synthetase has been purified to homogeneity from two N,-fixing cyanobacteria, Anabaena cylindrica and a species of Nostoc (the phycobiont of Peltigera canina). The activities of the A . cylindrica enzyme in the biosynthetic and transferase assays were, respectively, 9-4 and 32 pmol product formed min-l (mg protein)-l; the corresponding values for the Nostoc sp. enzyme were 6.5 and 20....

The description of soil microbial community structure by phospholipid fatty acid (PLFA) profiles is based on the relationship between the phylogeny of microorganisms and their PLFA profiles. Based on this relationship, two community based microbiological measurements, namely, potential C source utilization patterns in Biolog microtiter plates and PLFA profiles were used to examine metabolic fin...

Infocrop, a generic crop growth model was used to simulate the effect of Russian wheat aphid, Diuraphis noxia (Mordvilko) damage on winter wheat at Fort Collins and Akron, Colorado state, USA,. Observed and simulated yield reductions in four experiments over a period of two years were found to be closely related (R = 0.85). The aphid damage mechanisms coupled to the crop growth model could thus...

The origin of modern wheats involved alloploidization among related genomes. To determine if Aegilops speltoides was the donor of the B and G genomes in AABB and AAGG tetraploids, we used a 3-tiered approach. Using 70 amplified fragment length polymorphism (AFLP) loci, we sampled molecular diversity among 480 wheat lines from their natural habitats encompassing all S genome Aegilops, the putati...

UNLABELLED Leaf rust, caused by Puccinia triticina, is the most common rust disease of wheat. The fungus is an obligate parasite capable of producing infectious urediniospores as long as infected leaf tissue remains alive. Urediniospores can be wind-disseminated and infect host plants hundreds of kilometres from their source plant, which can result in wheat leaf rust epidemics on a continental ...

Common wheat (Triticum aestivum) has for decades been a textbook example of the evolution of a major crop species by allopolyploidization. Using a sophisticated extension of the PCR technique, we have successfully isolated two single-copy nuclear genes, DMC1 and EF-G, from each of the three genomes found in hexaploid wheat (BA(u)D) and from the two genomes of the tetraploid progenitor Triticum ...

Protein disulphide isomerase (PDI) is an oxidoreductase enzyme abundant in the endoplasmic reticulum (ER). In plants, PDIs have been shown to assist the folding and deposition of seed storage proteins during the biogenesis of protein bodies in the endosperm. Cloning and characterization of the complete set of genes encoding PDI and PDI like proteins in bread wheat (Triticum aestivum cv. Chinese...