Czech Journal of Genetics and Plant Breeding - In Press
Investigation of male fertility restoration in winter triticale (×Triticosecale Wittmack) with Pampa and Aegilops sharonensis cytoplasmsOriginal Paper
Alicja Matera, Magdalena Simlat
The study aimed to determine the number of restorer-of-fertility (Rf) genes and their mode of inheritance in winter triticale with Pampa and Aegilops sharonensis cytoplasms. The experiment was conducted under field conditions, where cytoplasmic male-sterile lines and lines with restored fertility, as well as the F1, F2, and BC1 generations, were examined. Male fertility/sterility was assessed using a five-step scale of anther appearance during flowering, and the number of grains per spike after harvesting. Additionally, for lines and the F1, pollen viability was examined using 1% aceto-carmine staining. A high value of correlation coefficients between both phenotyping methods (P < 0.001) indicates that CMS plant identification at an early flowering stage is possible. The genetic analysis of the segregating populations suggested that a single Rf gene is responsible for fertility restoration in both cytoplasms; however, further research should clarify whether this is the same gene. Additionally, incomplete male fertility restoration and lower pollen viability in the F1 progeny compared to paternal (restored) lines suggested the action of additional genes with minor effects. Future studies should clarify the chromosomal position of the main Rf gene and its modifiers with regard to Pampa and Ae. sharonensis cytoplasms.
Ultraviolet-B light regulates flavonoid biosynthesis in alfalfa (Medicago sativa L.)Original Paper
Hengwen Zhang, Tianjiang Liao, Hongzhu He, Tengjiao Niu, Yaning Song, Yajun Yan, Yajun Ma
Ultraviolet-B (UV-B) radiation acts as a significant environmental signal that modulates plant growth, development, and secondary metabolism. In this study, we investigated the metabolic and transcriptional responses of alfalfa (Medicago- sativa L.) seedlings exposed to UV-B radiation. Targeted metabolomic analysis revealed that six flavonoid compounds—liquiritigenin, formononetin, apigenin, naringenin, L-epicatechin, and glycitin—exhibited significant accumulation in response to UV-B treatment. Integrated transcriptomic analysis identified four key responsive enzymes involved in flavonoid biosynthesis: CHS (chalcone synthase), CHI1 (chalcone isomerase 1), FLS1 (flavonol synthase 1), and CYP75B1 (cytochrome P450), which catalyze the synthesis of the corresponding flavonoid metabolites. Furthermore, seven transcription factor genes, including MYB1 (Myb-related protein 1), MYB110 (Myb-related protein 110), F14D16.15 (Putative Myb-related transcription activator protein), SRM1 (Salt-Related MYB 1), GT-1 (Trihelix transcription factor GT-1), TT8 (TRANSPARENT TESTA 8), and HYH (ELONGATED HYPOCOTYL 5 homolog), were identified as putatively involved in the UV-B-responsive regulation of flavonoid biosynthesis. Among these, TT8 and MYB1 were selected for three-dimensional structural modeling based on protein-protein interaction predictions. These findings provide a theoretical foundation for understanding the regulatory mechanisms of flavonoid accumulation in alfalfa under UV-B stress and may inform strategies for enhancing stress tolerance in this important forage legume.
First characterisation of Tsn1 and Tsc2 specific sensitivity genes in Tunisian wheat in response to effectors genes of Pyrenophora tritici-repentisOriginal Paper
Salma Tissaoui, Noura Omri-Benyoussef, Marwa Hassine, Haifa BenMoussa, Bouzid Nasraoui, Amira Mougou-Hamdane
In the last decade, tan spot, a wheat foliar disease, has become more prevalent in North Africa and especially in Tunisia. The necrotrophic fungus Pyrenophora tritici-repentis (Ptr) is the causal agent and is characterised by distinct races which exhibit necrotrophic effector genes ToxA, ToxB, and toxb encoding the host specific toxins PtrToxA, and PtrToxB, respectively. The present study aimed to detect in wheat varieties the presence of Tsn1 and Tsc2 the specific sensitivity genes to the ToxA and ToxB necrotrophic effectors genes, using PCR method. Indeed, nineteen varieties of durum and bread wheat were inoculated with three races 5, 7, and an atypical race, under controlled conditions to determine the varieties’ reaction, and the Ptr-variety interaction profile. The race clustering shows two distinct groups, the first was composed of two races (5 and 7), but the second group is characterised by a different infection profile, including the atypical race. In addition, the analysis clusters the varieties into three main groups based on their susceptibility level. The group1 was composed of the variety Razzak and wheat line ‘Glenlea’ showing high susceptibility to race 5 and race 7, and harbouring the sensitivity genes Tsn1 and Tsc2. The second group was composed of seven durum wheat varieties of intermediate susceptibility to races, and it carried the sensitivity gene Tsc2. The group 3 was composed of the resistant varieties and it do not harbour any of the sensitivity genes, e.g. Zanzibar, Sensas, Cosaco, Accor, Haidra, Inrat100, Portodur, Salim, Sculptur, OumRabiaa, and Karim (all the bread wheat varieties and six durum wheat varieties). Therefore, the results would allow to recommend these varieties in high tan spot-incidence regions in Tunisia. This screening for resistance of the commercialised wheat varieties is the first report in Tunisia and North Africa, demonstrating the genetic richness of different varieties, which can be subsequently used in wheat breeding programs for sustainable tan spot management.