BackgroundStripe rust of wheat, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases of wheat worldwide. Due to special features of hexaploid wheat with large and complex genome and difficulties for transformation, and of Pst without sexual reproduction and hard to culture on media, the use of most genetic and molecular techniques in studying genes involved in the wheat-Pst interactions has been largely limited. The objective of this study was to identify transcriptionally regulated genes during an incompatible interaction between wheat and Pst using cDNA-AFLP techniqueResultsA total of 52,992 transcript derived fragments (TDFs) were generated with 64 primer pairs and 2,437 (4.6%) of them displayed altered expression patterns after inoculation with 1,787 up-regulated and 650 down-regulated. We obtained reliable sequences (>100 bp) for 255 selected TDFs, of which 113 (44.3%) had putative functions identified. A large group (17.6%) of these genes shared high homology with genes involved in metabolism and photosynthesis; 13.8% to genes with functions related to disease defense and signal transduction; and those in the remaining groups (12.9%) to genes involved in transcription, transport processes, protein metabolism, and cell structure, respectively. Through comparing TDFs identified in the present study for incompatible interaction and those identified in the previous study for compatible interactions, 161 TDFs were shared by both interactions, 94 were expressed specifically in the incompatible interaction, of which the specificity of 43 selected transcripts were determined using quantitative real-time polymerase chain reaction (qRT-PCR). Based on the analyses of homology to genes known to play a role in defense, signal transduction and protein metabolism, 20 TDFs were chosen and their expression patterns revealed by the cDNA-AFLP technique were confirmed using the qRT-PCR analysis.ConclusionWe uncovered a number of new candidate genes possibly involved in the interactions of wheat and Pst, of which 11 TDFs expressed specifically in the incompatible interaction. Resistance to stripe rust in wheat cv. Suwon11 is executed after penetration has occurred. Moreover, we also found that plant responses in compatible and incompatible interactions are qualitatively similar but quantitatively different soon after stripe rust fungus infection.

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To understand mitogenome characteristics and reveal phylogenetic relationships of the genus Ostrinia, including several notorious pests of great importance for crops, we sequenced the complete mitogenomes of four species: Ostrinia furnacalis (Guenée, 1854), Ostrinia nubilalis (Hübner, 1796), Ostrinia scapulalis (Walker, 1859) and Ostrinia zealis (Guenée, 1854). Results indicate that the four mitogenomes-O. furnacalis, O. nubilalis, O. scapulalis, and O. zealis-are 15,245, 15,248, 15,311, and 15,208 bp in size, respectively. All four mitogenomes are comprised of 37 encoded genes and a control region. All 13 protein-coding genes (PCGs) initiate with ATN and terminate with TAN, with the exception of cox1 that starts with CGA, and cox1, cox2, and nad5 that terminate with an incomplete codon T. All transfer RNA genes (tRNAs) present the typical clover-leaf secondary structure except for the trnS1 (AGN) gene. There are some conserved structural elements in the control region. Our analyses indicate that nad6 and atp6 exhibit higher evolution rates compared to other PCGs. Phylogenetic analyses based on mitogenomes using both maximum likelihood (ML) and Bayesian inference (BI) methods revealed the relationship (O. palustralis + (O. penitalis + (O. zealis + (O. furnacalis + (O. nubilalis + O. scapulalis))))) within Ostrinia. Insects 2020, 11, 232 2 of 15East Asia, and Northwestern Africa. Within this third species group, three subgroups are recognized according to the differences in male mid-tibia. The first subgroup contains four species including O. nubilalis and O. furnacalis with smaller mid-tibia and lacking any groove or scales. The second subgroup includes two species, namely O. kurentzovi (Mutuura and Munroe, 1970) and O. narynensis (Mutuura and Munroe, 1970), with a moderately dilated tibia and a fringe of enlarged curved scales. The third subgroup consists of four species, including O. scapulalis and O. zealis, possessing a strongly dilated tibia and massive scales in the groove. Mutuura and Munroe (1970) stated that the three species groups within the genus Ostrinia are monophyletic and indicated that O. penitalis is the most primitive species. The second group was defined as monophyletic because the members share potential synapomorphies in male genitalia [2]. The third species group has been intensively studied on the basis of their morphology, pheromones, and DNA sequence. Based on the complexity of the male tibia, Mutuura and Munroe (1970) considered that the species with the smallest tibia is the most primitive, then the species with the medium tibia are intermediate, and finally, the species with the large tibia and massive tuft are the most derived.Frolov (1981, 1984) stated that the variation in the male mid-tibia was determined by two alleles. The Mt and Mt + were two alleles located on autosomes and controlled the size of the mid-tibia, while i and i + were two alleles located on Z-sex-linked chromosomes and controlled the groove appearance. Mt/Mt + and i/i + follow a Mendelian inheritance pattern ...