Stable resistance to infection with Wheat streak mosaic virus (WSMV) can be evolved de novo in selfing bread wheat lines subjected to cycles of WSMV inoculation and selection of best-performing plants or tillers. To learn whether this phenomenon might be applied to evolve resistance de novo to pathogens unrelated to WSMV, we examined the responses to leaf rust of succeeding generations of the r...

Loblolly pines (Pinus taeda L.) thut were 8 to 17 yr old tolerated one to three fus[form rust (Cronartium quercuum [Berk.]Miyabe exShiraij sp. fusiforme) galls in theirstems. Families withfourormore galls in their stems lost 2.5% or more ofthe trees by age 17. In living trees with less thanf<jurstem galls, diameter growth was comparable to that of trees with no galls. Tolerance was indicated by...

Ammonium transporter (AMT) proteins have been reported in many plants, but no comprehensive analysis was performed in wheat. In this study, we identified 23 AMT members (hereafter TaAMTs) using a protein homology search in wheat genome. Tissue-specific expression analysis showed that TaAMT1;1a, TaAMT1;1b, and TaAMT1;3a were relatively more highly expressed in comparison with other TaAMTs. TaAMT...

(McIntosh and Gyarfas 1971, Gill et al. 1983, Tomar et al. 1988, Brown-Guedira et al. 1996). Cultivated T. timopheevii has been used for wheat improvement to a greater extent than has its wild progenitor, T. araraticum. Because T. timopheevii is a cultivated species, the chances of recovering agronomically acceptable derivatives from crosses with wheat are greater. However, T. timopheevii is en...

Puccinia graminis f. sp. tritici is the causal agent of stem rust of wheat. A new race designated TTKSK (also known as Ug99) and its variants (TTKST and TTTSK) are virulent to most of the stem rust resistance genes currently deployed in wheat cultivars worldwide. Therefore, identi! cation, mapping, and deployment of effective resistance genes are critical components of global efforts to mitigat...

Wheat is globally one of the most important crops. With the current human population growth rate, there is an increasing need to raise wheat productivity by means of plant breeding, along with development of more efficient and sustainable agricultural systems. Damage by pathogens and pests, in combination with adverse climate effects, need to be counteracted by incorporating new germplasm that ...

Stem rust of wheat caused by the fungal pathogen Puccinia graminis f. sp. tritici historically caused major yield losses of wheat worldwide. To understand the genetic basis of stem rust resistance in contemporary North American spring wheat, genome-wide association analysis (GWAS) was conducted on an association mapping panel comprised of 250 elite lines. The lines were evaluated in separate nu...

This study reports the identification of a new gene conferring resistance to the Ug99 lineage of races of Puccinia graminis f. sp. tritici in wheat (Triticum aestivum L.). Because the virulent races of stem rust pathogen continue to pose a serious threat in global wheat production, identification and molecular characterization of new resistance genes remains of utmost important to enhance resis...

Wheat stem rust (Puccinia graminis f. sp. tritici Eriks. and E. Henn.) is one of the most destructive diseases world-wide. Races belonging to Ug99 (or TTKSK) continue to cause crop losses in East Africa and threaten global wheat production. Developing and deploying wheat varieties with multiple race-specific genes or complex adult plant resistance is necessary to achieve durability. In the pres...