With 2 figures and 5 tables
Tef Eragrostis tef (Zucc.) Trotter is an important food staple cereal crop in Ethiopia. Despite its importance in the Ethiopian agriculture, there are constraints that ...need to be addressed through scientific research. The major constraints are low yield of landrace cultivars under widespread cultivation, susceptibility to lodging and a lack of knowledge concerning the genetic control of agronomic traits. Conventional tef breeding efforts started in the late 1950s, and since then a total of 24 varieties have been developed and released. Yield gain from tef breeding has been linear with an average annual increase of 0.8%. Tef genomics has provided much molecular genetic information on important agronomic traits. More than 1500 PCR‐based molecular markers have been developed and several genetic linkage maps based on intra‐ and inter‐specific crosses have been constructed. Results from quantitative trait loci studies have provided information necessary for marker‐assisted selection. Lodging is the number one cause of yield loss in tef. Recently, molecular breeding techniques and biotechnologies are being employed to understand the genetic control of lodging.
•Teff has gained research importance in gluten free food market.•Various teff based gluten free products have been developed.•Various techniques have been tested to improve the quality of teff ...products.•Genetic diversity in agronomic traits of teff have been recorded.•Attractive nutrients are protein, fiber, polyphenols, and minerals (e.g., Fe).
Teff (Eragrostis tef) is a cereal native to Ethiopia and Eritrea. It has an excellent adaptability to harsh environmental conditions and plays an important role in food security. In recent years, teff is becoming globally popular due to the attractive nutritional profile such as gluten free and high dietary fiber content. This review documents the recent advances in the genetic diversity, nutritional composition and food uses of teff grain. The attractive nutrients of teff include protein, dietary fiber, polyphenols, and certain minerals. Whole grain teff flour becomes increasingly important in healthy food market, and has been used to produce various gluten free food items such as pasta and bread. Efforts have been made to enhance the sensory quality of teff based products. There is great potential to adapt teff to the other parts of the world for healthy food and beverage production.
Tef Eragrostis tef (Zucc.) Trotter is a cereal crop resilient to adverse climatic and soil conditions, and possessing desirable storage properties. Although tef provides high quality food and grows ...under marginal conditions unsuitable for other cereals, it is considered to be an orphan crop because it has benefited little from genetic improvement. Hence, unlike other cereals such as maize and wheat, the productivity of tef is extremely low. In spite of the low productivity, tef is widely cultivated by over six million small-scale farmers in Ethiopia where it is annually grown on more than three million hectares of land, accounting for over 30% of the total cereal acreage. Tef, a tetraploid with 40 chromosomes (2n = 4x = 40), belongs to the family Poaceae and, together with finger millet (Eleusine coracana Gaerth.), to the subfamily Chloridoideae. It was originated and domesticated in Ethiopia. There are about 350 Eragrostis species of which E. tef is the only species cultivated for human consumption. At the present time, the gene bank in Ethiopia holds over five thousand tef accessions collected from geographical regions diverse in terms of climate and elevation. These germplasm accessions appear to have huge variability with regard to key agronomic and nutritional traits. In order to properly utilize the variability in developing new tef cultivars, various techniques have been implemented to catalog the extent and unravel the patterns of genetic diversity. In this review, we show some recent initiatives investigating the diversity of tef using genomics, transcriptomics and proteomics and discuss the prospect of these efforts in providing molecular resources that can aid modern tef breeding.
Tef research has little benefited from omics due to neglect of the crop by the global scientific community. However, the few utilized tools showed promising results.Chromosome-scale assembly of the ...genome reveals the evolution of tef. The whole-genome sequencing of drought-resurrecting Eragrostis nindensis and desiccation-sensitive Eragrostis curvula shows genes that play key roles in drought responses.A few studies using omics tools have revealed differentially expressed genes, proteins, and metabolites in tef plants exposed to drought.Molecular markers have deciphered diversity in tef germplasm collected from diverse agroecologies in Ethiopia.The application of targeting induced local lesions in genomes resulted in mutant tef lines with a semidwarf stature, which were later bred to locally adapted and high-yielding varieties.Genome editing using ‘Green Revolution’ genes resulted in a semidwarf and lodging-tolerant tef plant.
Tef or teff Eragrostis tef (Zucc.) Trotter is a cereal crop indigenous to the Horn of Africa, where it is a staple food for a large population. The popularity of tef arises from its resilience to environmental stresses and its nutritional value. For many years, tef has been considered an orphan crop, but recent research initiatives from across the globe are helping to unravel its undisclosed potential. Advanced omics tools and techniques have been directed toward the exploration of tef’s diversity with the aim of increasing its productivity. In this review, we report on the most recent advances in tef omics that brought the crop into the spotlight of international research.
Tef or teff Eragrostis tef (Zucc.) Trotter is a cereal crop indigenous to the Horn of Africa, where it is a staple food for a large population. The popularity of tef arises from its resilience to environmental stresses and its nutritional value. For many years, tef has been considered an orphan crop, but recent research initiatives from across the globe are helping to unravel its undisclosed potential. Advanced omics tools and techniques have been directed toward the exploration of tef’s diversity with the aim of increasing its productivity. In this review, we report on the most recent advances in tef omics that brought the crop into the spotlight of international research.
Effective chemical hybridizing agents (CHAs) or male gametocides enhance cross pollination in plant breeding and genetic analysis of traits. The present study examined the efficacy and optimum ...concentration of four CHAs, namely: 2-chloroethyl phosphonic acid (Ethrel), ethyl 4'-fluorooxanilate (E4FO), 2, 4-dichlorphenoxy acetic acid (2, 4-D) and Promalin super( registered ) (1.8% GA sub(47 )- gibberellins A sub(4)+A sub(7) and 1.8% 6-BA-benzyladenine) on pollen sterility and seeding of a tef line (DZ-01-3186). Seed-derived and individually grown tef plants were treated with foliar applications of the four CHAs (at four levels each) sprayed once at the early booting stage, and bagged to control cross pollination. Female fertility was assessed by recording seed set following controlled pollinations. Although all the CHAs caused some pollen sterility, their efficacy levels varied from 9.77 to 99.50% in treated plants compared to the control (6.68 +/- 1.04%). Pollen sterility increased with increasing CHA concentration. Near-complete pollen sterility (99.50 plus or minus 0.50%) was achieved by the application of E4FO at rates of 1500 to 3000 ppm, and Ethrel at 5000 ppm. All the CHAs significantly reduced seed yield, with E4FO, Ethrel and Promalin super( registered ) at 5000 ppm causing the highest reduction, essentially yielding no seed. In the period following the application of the CHAs, plants treated with E4FO (1000 - 1500 ppm) exhibited stigmas that remained fertile. Hence, it is recommended that E4FO (at 1000 - 1500 ppm) can be used as a chemical emasculation agent for tef, with the least phytotoxicity and the highest female fertility.
Various techniques for tracheoesophageal fistula cannulation have been reported. In this case, we created a loop using a plastic catheter. The loop allowed us to create traction for rapid ...intraoperative localization and to pull a difficult‐to‐reach fistula, superiorly into the neck, to be reached through a cervical approach.
Laryngoscope, 133:2425–2427, 2023
Research background. Teff Eragrostis tef (Zucc.) Trotter is an underutilised cereal crop
grown mainly in Ethiopia and Eritrea. It is an excellent source of dietary fibre, vitamins,
minerals and ...bioactive compounds. However, it also contains a high amount of phytic
acid, which is an antinutrient and reduces the bioavailability of minerals and proteins. To
improve the nutritional quality of teff, the phytic acid content should be reduced by an
effective dephytinisation method.
Experimental approach. In this study, various dephytinisation methods (fermentation,
autoclaving and phytase treatment) were used to dephytinise teff flour. Undephytinised
and dephytinised teff flour was mixed into wheat flour (0−40 %) to improve the functional
properties of cookies. Twenty different cookie formulations were prepared according
to 4x5x2 factorial design. The physical, chemical, nutritional and sensory properties of the cookies were investigated.
Results and conclusions. Among the dephytinisation methods, fermentation produced
the most effective reduction in phytic acid mass fraction (181 mg/100 g), followed by phytase treatment (198 mg/100 g). The protein, fat, Fe and Zn content and antioxidant activity of cookies enriched with dephytinised teff flour were comparable to cookies fortified with undephytinised teff flour. Moreover, the dephytinised teff cookies had lower phytic acid mass fractions. The cookies containing 40 % teff flour had higher antioxidant activity and nutritional quality than the control wheat cookies. The use of dephytinised teff flour reduced the spread ratio and the a* and b* values of cookies compared to undephytinised flour. Cookies containing fermented and phytase-treated teff flour had a harder texture than cookies containing undephytinised flour. In addition, as the amount of teff flour increased, the spread ratio values of cookies gradually incrased while their hardness decreased.
Overall acceptability scores of cookies containing 10–20 % teff flour were similar to the control.
Novelty and scientific contribution. To the best of our knowledge, this is the first study
to determine the quality of cookies containing dephytinised teff flour. The data highlight
the potential of dephytinised (especially autoclaved and phytase-treated) teff flour (up to
20 %) as a functional ingredient to enrich the mineral content and antioxidant capacity of
foods. Furthermore, this study shows that fermentation, autoclaving and phytase treatment can be used to improve the nutritional quality of grains.
Tef
(Zucc.) Trotter is an important crop in the Horn of Africa, particularly in Ethiopia, where it is a staple food for over 60 million people. However, the productivity of tef remains extremely low ...in part due to its susceptibility to lodging. Lodging is the displacement of the plant from the upright position, and it is exacerbated by rain, wind and the application of fertilizer. In order to address the issue of global food security, especially in the Horn of Africa, greater insight into the causes of tef lodging is needed. In this study, we combine modeling and biomechanical measurements to compare the properties relating to lodging tolerance in high yielding, improved tef genotypes, and lower yielding natural landraces. Our results indicate that the angle of the panicle contributes to the likelihood of lodging in tef. Varieties with compact panicles and reduced height had increased lodging resistance compared to the other varieties. By comparing different varieties, we found that overall, the landraces of tef lodged less than improved varieties. We constructed a model of stem bending and found that panicle angle was an important determinant of the amount of lodging. The findings from this study provide key information to those involved in tef improvement, especially those interested in lodging tolerance.
•The study investigates synchronous and asynchronous teacher electronic feedback (TEF) in ESL writing classes.•TEF was extracted from 93 drafts written by 64 students and 93 chats.•Student and ...teacher perceptions about TEF were solicited.•Most TEF was successfully implemented or attempted, focused on content, and was positively perceived.•Synchronous TEF effectively reinforces asynchronous TEF.
We know little about how teacher feedback and student revisions are influenced when feedback is given electronically. This study contributes to a better understanding of teacher electronic feedback (TEF) in second language writing by investigating its effectiveness in face-to-face and online ESL writing classes in which TEF was offered asynchronously, as Word comments and track changes in electronic drafts, as well as in synchronous text chats between teachers and students. TEF was extracted from 93 drafts written by 64 students and 93 chats in which they conferenced with their teachers. Students’ perceptions about TEF were then solicited via a survey. Additionally, the three participating teachers were interviewed about their use of TEF. Findings show that most TEF was successfully implemented or attempted, and that it was focused on content. Important conclusions are that TEF is effective, and synchronous TEF effectively reinforces asynchronous TEF.
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