The hypersensitive reaction in incompatible wheat-rust interactions is characterized by an increase in lipoxygenase activity detectable as early as 28 h after penetration o f the pathogen. In contrast, lipoxygenase activity in the compatible interaction did not increase until the onset of sporulation. Lipoxygenase activity also increased following treatment o f wheat leaves with an elicitor fra...

Take-all disease of Poaceae is caused by Gaeumannomyces graminis (Magnaporthaceae). Four varieties are recognised in G. graminis based on ascospore size, hyphopodial morphology and host preference. The aim of the present study was to clarify boundaries among species and varieties in Gaeumannomyces by combining morphology and multi-locus phylogenetic analyses based on partial gene sequences of I...

Race Ug99 of the fungus Puccinia graminis tritici that causes stem or black rust disease on wheat was first detected in Uganda in 1998. Seven races belonging to the Ug99 lineage are now known and have spread to various wheat-growing countries in the eastern African highlands, as well as Zimbabwe, South Africa, Sudan, Yemen, and Iran. Because of the susceptibility of 90% of the wheat varieties g...

Five accessions of Aegilops speltoides and 67 European wheat cultivars (winter and spring) originating from the Czech Republic, Germany, Poland, Russia, Slovakia, United Kingdom, and 4 non-European wheat cultivars from Brazil and the USA were examined with molecular Sequence Tagged Site (STS) markers for resistance genes to powdery mildew: Pm 1, Pm 2, Pm 3 and Pm 13. All markers gave clear, rep...

Background Puccinia psidii causes rust disease on many host species in the Myrtaceae [1]. First reported in 1884 on guava in Southern Brazil [2], the rust has since been detected on several myrtaceous in South America, Central America, Caribbean, Mexico, USA: in Florida, California, and Hawaii. More recently, P. psidii was reported in Japan infecting M. polymorpha[3]. Of special note is that a ...

Antigens and antisera from in vitro cultures of Puccinia melanocephala Sydow, uredospores collected from the field and sugar cane varieties were obtained. Cross-reactions were detected between the fungi and plants by counterimmunoelectrophoresis, immunoelectrophoresis and indirect ELISA. The last technique detected more antigenic relationships with the susceptible plants. This result may be use...

Disssion: A New Species of Mono-mucor on Chinese Soybean Cheese: NGANSHOU W.U. Concerning Heterothallism in Puccinia graminis: DR. RUTH F. ALLEN. A Use of Journals by Research Men: DR. J. L. ST. JOHN. Functions of Review Journals: DR. CARL G. HARTMAN. ........ .307 Scientific Apparatus and Laboratory Methods: New Technique for Collecting Intestinal Roundworms: DR. JAIMES E. ACKERT and L. 0. NOL...

A new model for grass functional genomics is described based on Brachypodium distachyon, which in the evolution of the Pooideae diverged just prior to the clade of "core pooid" genera that contain the majority of important temperate cereals and forage grasses. Diploid ecotypes of B. distachyon (2n = 10) have five easily distinguishable chromosomes that display high levels of chiasma formation a...