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Wheat powdery mildew, which is mainly caused by Blumeria graminis f. sp. tritici (Bgt), seriously damages wheat production. The wheat-Thinopyrum intermedium alien addition disomic line germplasm SN6306, being one of the important sources of genes for wheat resistance, is highly resistant to Bgt E09 and to many other powdery mildew physiological races. However, knowledge on the resistance mechanism of SN6306 remains limited. Our study employed high-throughput RNA sequencing based on next-generation sequencing technology (Illumina) to obtain an overview of the transcriptome characteristics of SN6306 and its parent wheat Yannong 15 (YN15) during Bgt infection. The sequencing generated 104,773 unigenes, 9909 of which showed varied expression levels. Among the 9909 unigenes, 1678 unigenes showed 0 reads in YN15. The expression levels in Bgt-inoculated SN6306 and YN15 of exactly 39 unigenes that showed 0 or considerably low reads in YN15 were validated to identify the genes involved in Bgt resistance. Among the 39 unigenes, 12 unigenes were upregulated in SN6306 by 3-45 times. These unigenes mainly encoded kinase, synthase, proteases, and signal transduction proteins, which may play an important role in the resistance against Bgt. To confirm whether the unigenes that showed 0 reads in YN15 are really unique to SN6306, 8 unigenes were cloned and sequenced. Results showed that the selected unigenes are more similar to SN6306 and Th. intermedium than to the wheat cultivar YN15. The sequencing results further confirmed that the unigenes showing 0 reads in YN15 are unique to SN6306 and are most likely derived from Th. intermedium (Host) Nevski. Thus, the genes from Th. intermedium most probably conferred the resistance of SN6306 to Bgt., (Copyright © 2016 Elsevier B.V. All rights reserved.)

YUCCA protein participates in a key rate-limiting step in the tryptophan-dependent pathway for auxin biosynthesis and is involved in numerous processes during plant development. In this study, the genomic and cDNA sequences of three TaYUC10 homoeologous genes were isolated. These sequences showed a very high conservation in coding region and the exon/intron structure, whereas their intron lengths were different. The cDNA and polypeptide chains of the three TaYUC10 genes were highly similar. These genes were most homologous to BdYUC10. Location analysis showed that TaYUC10.1 was present in chromosome 5BL. TaYUC10.3 was expressed in all parts of the wheat, but was predominant in the reproductive organs of mature wheat, such as flowering spikelets or fertilized embryos. In the fertilized embryos 28d post-anthesis, expression of TaYUC10.3 was clearly increased with the development of seeds. This indicates that TaYUC genes may play a vital role in seed development. TaYUC10.3 overexpressed in Arabidopsis had a typical phenotype, excessive auxin accumulation also seen in higher plants, and showed increased spacing of silique and downward curling of the blade margin. Sterility was observed in adult transgenic plants, becoming more severe in late development. The floral structures of sterile plants were not integrated. TaYUC10 may be required for numerous wheat growth processes, including flower and seed development., (Copyright © 2014 Elsevier B.V. All rights reserved.)