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The discovery of induced pluripotent stem cells (iPSCs) has made an invaluable contribution to the field of regenerative medicine, paving way for identifying the true potential of human embryonic stem cells (ESCs). Since the controversy around ethicality of ESCs continue to be debated, iPSCs have been used to circumvent the process around destruction of the human embryo. The use of iPSCs have transformed biological research, wherein increasing number of studies are documenting nuclear reprogramming strategies to make them beneficial models for drug screening as well as disease modelling. The flexibility around the use of iPSCs include compatibility to non-invasive harvesting, and ability to source from patients with rare diseases. iPSCs have been widely used in cardiac disease modelling, studying inherited arrhythmias, neural disorders including Alzheimer’s disease, liver disease, and spinal cord injury. Extensive research around identifying factors that are involved in maintaining the identity of ESCs during induction of pluripotency in somatic cells is undertaken. The focus of the current review is to detail all the clinical translation research around iPSCs and the strength of its ever-growing potential in the clinical space.

Recent technological advances in next-generation sequencing (NGS) technologies have dramatically reduced the cost of DNA sequencing, allowing species with large and complex genomes to be sequenced. Although bread wheat (Triticum aestivum L.) is one of the world’s most important food crops, efficient exploitation of molecular marker-assisted breeding approaches has lagged behind that achieved in other crop species, due to its large polyploid genome. However, an international public–private effort spanning 9 years reported over 65% draft genome of bread wheat in 2014, and finally, after more than a decade culminated in the release of a gold-standard, fully annotated reference wheat-genome assembly in 2018. Shortly thereafter, in 2020, the genome of assemblies of additional 15 global wheat accessions was released. As a result, wheat has now entered into the pan-genomic era, where basic resources can be efficiently exploited. Wheat genotyping with a few hundred markers has been replaced by genotyping arrays, capable of characterizing hundreds of wheat lines, using thousands of markers, providing fast, relatively inexpensive, and reliable data for exploitation in wheat breeding. These advances have opened up new opportunities for marker-assisted selection (MAS) and genomic selection (GS) in wheat. Herein, we review the advances and perspectives in wheat genetics and genomics, with a focus on key traits, including grain yield, yield-related traits, end-use quality, and resistance to biotic and abiotic stresses. We also focus on reported candidate genes cloned and linked to traits of interest. Furthermore, we report on the improvement in the aforementioned quantitative traits, through the use of (i) clustered regularly interspaced short-palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9)-mediated gene-editing and (ii) positional cloning methods, and of genomic selection. Finally, we examine the utilization of genomics for the next-generation wheat breeding, providing a practical example of using in silico bioinformatics tools that are based on the wheat reference-genome sequence.

Fusarium graminearum Schwabe causes Fusarium head blight (FHB), a devastating disease that leads to extensive yield and quality loss of wheat and other cereal crops. Twelve isolates of F. graminearum were collected from naturally infected spikes of wheat from Assiut Egypt. These isolates were compared using SRAP. The results indicated distinct genetic groups exist within F. graminearum, and demonstrated that these groups have different biological properties, especially with respect to their pathogenicity on wheat. There were biologically significant differences between the groups; with group (B) isolates being more aggressive towards wheat than groups (A) and (C). Furthermore, Trichoderma harzianum (Rifai) and Bacillus subtilis (Ehrenberg) which isolated from wheat kernels were screened for antagonistic activity against F. graminearum. They significantly reduced the growth of F. graminearum colonies in culture. In order to gain insight into biological control effect in situ, highly antagonistic isolates of T. harzianum and B. subtilis were selected, based on their in vitro effectiveness, for greenhouse test. It was revealed that T. harzianum and B. subtilis significantly reduced FHB severity. The obtained results indicated that T. harzianum and B. subtilis are very effective biocontrol agents that offer potential benefit in FHB and should be harnessed for further biocontrol applications. The accurate analysis of genetic variation and studies of population structures have significant implications for understanding the genetic traits and disease control programs in wheat. This is the first known report of the distribution and genetic variation of F. graminearum on wheat spikes in Assiut Egypt.

Faba bean (Vicia faba L.) is one of the most important legume crops in Egypt. However, production of faba bean is affected by several diseases including fungal diseases. Fusarium wilt incited by Fusarium oxysporum Schlecht. was shown to be the most common wilt disease of faba bean in Assiut Governorate. Evaluation of 16 faba bean genotypes for the resistance to Fusarium wilt was carried out under greenhouse conditions. Three molecular marker systems (inter-simple sequence repeat [ISSR], sequence related amplified polymorphism [SRAP], and simple sequence repeat [SSR]) and a biochemical marker (protein profiles) were used to study the genetic diversity and detect molecular and biochemical markers associated with Fusarium wilt resistance in the tested genotypes. The results showed that certain genotypes of faba bean were resistant to Fusarium wilt, while most of the genotypes were highly susceptible. The percentage of disease severity ranged from 32.83% in Assiut-215 to 64.17% in Misr-3. The genotypes Assiut-215, Roomy-3, Marut-2, and Giza-2 were the most resistant, and the genotypes Misr-3, Misr-1, Assiut-143, Giza-40, and Roomy-80 performed as highly susceptible. The genotypes Assiut-215 and Roomy-3 were considered as promising sources of the resistance to Fusarium wilt. SRAP markers showed higher polymorphism (82.53%) compared with SSR (76.85%), ISSR markers (62.24%), and protein profile (31.82%). Specific molecular and biochemical markers associated with Fusarium wilt resistance were identified. The dendrogram based on combined data of molecular and biochemical markers grouped the 16 faba bean genotypes into three clusters. Cluster I included resistant genotypes, cluster II comprised all moderate genotypes and cluster III contained highly susceptible genotypes.

Fusarium is one of the most dangerous fungal diseases that cause great loss of the sesame yield worldwide. The present work aimed to improve tolerance and/or resistance to Fusarium through two cycles of pedigree selection on sesame population for eight selection criteria started in the F 3 -generation. Genotypic coefficient of variability in the F 3 varied from 4.34% for days to 50% flowering to 38.15% for seed yield (SY/P). Days to 50% flowering showed negative correlations with all traits except height to first capsule (HFC). Height to first capsule was negatively correlated with length of fruiting zone (LFZ), 1000-SW, oil% and infection%, and positively correlated with capsules/plant (NC/P) and SY/P. Single trait selection was an efficient method to improve selection criterion, but it caused adverse effects on some correlated traits. Selection for days to 50% flowering improved earliness, but it was better in improving yield if the selection was restricted by SY/P. Selection for oil% restricted by yield was better in improving yield than selection for oil% per se. Therefore, the inclusion of a trait as independent culling level improved the efficiency of selection. The best genetic gain in SY/P in percentage from the mid-parent was obtained from selection for days to 50% flowering restricted by SY/P (35.56 ** ), LFZ restricted by HFC (19.53 ** ), days to 50% flowering (19.32 ** ), oil% restricted by SY/P (19.02 ** ), SY/P (17.38 ** ), 1000 SW (14.09 ** ) and LFZ (14.032 ** ). Therefore, selection index incorporating favorable trait is recommended.

Charcoal rot symptoms were observed on 2-month-old oilseed sunflower plants (Helianthus annuus L.) in the Eskişehir Province of Turkey in June 2009. The disease was observed in 70% of the fields surveyed and incidence ranged from 10 to 50%. Symptoms were first observed in plants approaching physiological maturity and consisted of silver-gray lesions girdling the stem at the soil line, reduced head diameter compared with noninfected plants, and premature plant death. Pith in the lower stem was completely absent or compressed into horizontal layers. Black, spherical microsclerotia were observed in the pith area of the lower stem, underneath the epidermis, and on the exterior of the taproot. The internal stem had a shredded appearance. Later, the vascular bundles became covered with small, black flecks or microsclerotia of the fungus. Forty plant samples were collected from 10 fields. After surface sterilization with 2% NaOCl, outer tissues sampled from diseased tissues (2 to 3 mm long) of root and stems were removed and transferred to potato dextrose agar containing 250 mg liter–1 of chloramphenicol. Petri plates were incubated for 7 days at 26 ± 2°C in the dark. Ninety-eight percent of the fungal colonies were identified as Macrophomina phaseolina (Tassi) Goidanich based on gray colony color, colony morphology, and the size of the microsclerotia, which ranged from 80 to 90 μm in diameter, from both infected sunflowers and compared with pure cultures (3). All resulting cultures produced abundant microsclerotia. The only other sunflower pathogen known to form microsclerotia is Verticillium dahliae Kleb., whose microsclerotia are irregular in shape and 15 to 50 μm in diameter. Sequence-related amplified polymorphisms technique was used for diversity of M. phaseolina since it has proven to be more informative than amplified fragment length polymorphism, random amplified polymorphic DNA, and simple sequence repeat (2). Results showed a high level of genetic diversity (60%) among the 26 isolates of M. phaseolina. Sequencing of the internal transcribed spacer region (1) showed high homology (>96%) to M. phaseolina (GenBank Accession No. HQ380051). Pathogenicity tests for 20 isolates of M. phaseolina were carried out on three commercially used cultivars, SANAY, TUNCA, and TR-3080. Groups of 10 seedlings were grown separately in an autoclaved peat/soil mixture in 30-cm-diameter plastic pots in a greenhouse at 30 ± 2°C. Soil infestation was performed 1 day before sowing. Two-week-old cultures on barley medium (4) were blended in distilled sterile water and adjusted to 105 sclerotia ml–1. Each pot received 250 ml of inoculant. Each treatment had three replications. Three pots for each cultivar were left uninoculated. Within 3 weeks, five to seven inoculated plants in each pot died. Identical disease symptoms were observed 30 days after inoculation; on the control plants no symptoms were observed. Microsclerotia were produced after 7 weeks at the stem base on 85% of the surviving plants. To our knowledge, this is the first report of M. phaseolina in sunflower in Turkey. References: (1) B. D. Babu et al. J. Plant Dis. Prot. 96:797, 2007. (2) H. Budak et al. Theor. Appl. Genet. 109:280, 2004. (3) P. Holliday and E. Punithalingam. No. 275 in: Description of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1970. (4) M. R. Omar et al. J. Plant Dis. Prot. 114:196, 2007.

Charcoal rot disease, a root and stem disease caused by the soil-borne fungus Macrophomina phaseolina (Tassi) Goid., is a major biotic stress that limits sorghum productivity worldwide. Charcoal rot resistance-related parameters, e.g., pre-emergence damping-off%, post-emergence damping-off%, charcoal rot disease severity, and plant survival rates, were measured in a structured sorghum population consisting of 107 landraces. Analysis of variance of charcoal rot resistance-related parameters revealed significant variations in the response to M. phaseolina infection within evaluated accessions. Continuous phenotypic variations for resistance-related parameters were observed indicating a quantitative inheritance of resistance. The population was genotyped using 181 simple sequence repeat (SSR) markers. Association analysis identified 13 markers significantly associated with quantitative trait genes (QTLs) conferring resistance to charcoal rot disease with an R value ranging between 9.47 to 18.87%, nine of which are environment-specific loci. Several QTL-linked markers are significantly associated with more than one resistance-related parameter, suggesting that those QTLs might contain genes involved in the plant defense response. In silico analysis of four novel major QTLs identified 11 putative gene homologs that could be considered as candidate genes for resistance against charcoal rot disease. Cluster analysis using the genotypic data of 181 SSR markers from 107 sorghum accessions identified 12 main clusters. The results provide a basis for further functional characterization of charcoal rot disease resistance or defense genes in sorghum and for further dissection of their molecular mechanisms.