11 research outputs found

    Regulation of shoot growth, root development and manganese allocation in wheat ( Triticum aestivum ) genotypes by light intensity

    Get PDF
    The objective of this study was to assess effects of different light intensities on shoot growth, root development and allocation of root-borne solutes via the transpiration stream to various shoot parts of young wheat plants (Triticum aestivum L.). Hydroponic culture allowed direct access to the roots and shoots throughout the experiment. Under low light intensity (100μmol photons m−2s−1), shoot growth was restricted, less (but larger) leaves were produced at the main shoot and only a few tillers became visible as compared to plants under high light intensity (380μmol photons m−2s−1). The root system was indirectly also affected by the illumination of the aerial parts. A larger number of shorter roots were produced under high light leading to a denser root system, while only a small number of longer roots were present under low light. The distribution of 54Mn (xylem-mobile, but essentially phloem-immobile in wheat) from the roots to the shoot lead to the conclusion that light regime strongly influences the distribution of root-borne solutes within the shoots. Labels introduced into the roots may allow a deeper insight into the transfer of solutes from the root system to the various shoot parts under different light regime

    Tef (Eragrostis tef) Variety ‘Tesfa’

    Get PDF
     አህፅሮት ጤፍ በኢትዮጵያ ከሚመረቱ የብርዕና አገዳ ሰብሎች ዋናው ሲሆን በየዓመቱ ቁጥር ከ6.5 ሚሊዮን የማያንስ አርሶ አደር ያመርተዋል፡፡ ይህም አጠቃላይ በብርዕና አገዳ ሰብሎች ከሚሸፈነው ማሳ 30% ድርሻ አለው፡፡ ይሁን እንጂ ከሌሎች ሰብሎች ጋር ሲነፃፀር ምርታማነቱ አነስተኛ ነው፡፡ ለዚህም ምክንያቱ በከፊል አርሶ አደሩ ያልተሻሻሉ የአካባቢ ዝርያዎችን በመጠቀሙና፣ የሰብሉ ተፈጥሯዊ የመጋሸብ ባህሪ ናቸው፡፡  የዚህ ጥናት ዓላማ በተለየ ምርምር አሰራር የተገኘን የጤፍ ዝርያን በመፈተሸ የተሻለ ምርት፤ የአገዳ ጥንካሬን አንዲሁም የዘር ቀለም ያለውና በአርሶ አደሩ ተመራጭ ዝርያ ማፍለቅ ነበር፡፡ በጥናቱ በቅርቡ የተለቀቀ አንድ ዝርያና አንድ የአካባቢ ዝርያን ጨምሮ 10 የተለያዩ የጤፍ አይነቴዎችን በማካተት በስድስት ወካይ ጤፍ አብቃይ ቦታዎች ላይ ተፈትሸው ተስፋ (ደዘ-ክሮስ-457) ተብሎ የተሰየመውና የተለያዩ የጤፍ አይነቴዎች ተዳቅለው የተገኘው ዝርያ ከሌሎች ማወዳደሪያ ተፈታሽ ዝርያዎች የተሻለ ውጤት በማስመዝገቡ በብሄራዊ የዝርያ አፅዳቂ ኮሚቴ ተገምግሞ ለምርት እንዲለቀቅ ተወስኗል፡፡ ይህ ዝርያ ከሌሎች ዝርያዎች በንፅፅር መጋሸብን በመቋቋሙ፤ የተሻለ ምርት በመስጠቱ በአርሶአደሩ ተፈላጊ ከመሆኑም በሻገር ከዝርያው ባህሪ የተነሳ ለመስኖ እርሻና በሰብል መድረሻ ጊዜ የማጨጃ የእርሻ መሳሪያ መጠቀም ያስችላል፡፡ Abstract Tef [Eragrostis tef (Zucc.) Trotter] is extensively cultivated cereal crop in Ethiopia where it is annually grown by about 6.5 million smallholder farmers on about 30% of the total area allocated to cereal crops.However, the productivity of tef is very low compared to other cereals mainly due to lack of high yielding and lodging tolerant cultivars. The objective of this study was to evaluate the performance of the recently released tef variety called Tesfaand to provide unique morphological and agronomic descriptions of this new variety. Ten genotypes which were derived from three independent crosses and bred for at least eight generations plus a local and standard check varieties were tested at six tef growing sites in Ethiopia (namely, Adet, Chafe Donsa,DebreZeit black soil, DebreZeit light soil,Ginchiand Holetta) using RandomizedCompleteBlock Design with three replications. The study found that Tesfa(DZ-Cr-457 RIL-181) which was obtained from a cross between kinde (a semi-dwarf mutant line developed at the University of Bern, Switzerland) and Kay Murri(a landrace) outperformed other genotypes and approved for release by the Ethiopian National Variety Release Committee in March 2017.The main advantages of Tesfa over other tested lines were its higher grain yield and higher lodging tolerance. In addition, Tesfa possesses unique properties for which high acceptance by growers is expected. These are its compact panicle, lack of shattering, and thick and strong culm which makes it potentially cultivated under irrigation and also mechanically harvested

    Technology generation to dissemination:lessons learned from the tef improvement project

    Get PDF
    Indigenous crops also known as orphan crops are key contributors to food security, which is becoming increasingly vulnerable with the current trend of population growth and climate change. They have the major advantage that they fit well into the general socio-economic and ecological context of developing world agriculture. However, most indigenous crops did not benefit from the Green Revolution, which dramatically increased the yield of major crops such as wheat and rice. Here, we describe the Tef Improvement Project, which employs both conventional- and molecular-breeding techniques to improve tef\u2014an orphan crop important to the food security in the Horn of Africa, a region of the world with recurring devastating famines. We have established an efficient pipeline to bring improved tef lines from the laboratory to the farmers of Ethiopia. Of critical importance to the long-term success of this project is the cooperation among participants in Ethiopia and Switzerland, including donors, policy makers, research institutions, and farmers. Together, European and African scientists have developed a pipeline using breeding and genomic tools to improve the orphan crop tef and bring new cultivars to the farmers in Ethiopia. We highlight a new variety, Tesfa, developed in this pipeline and possessing a novel and desirable combination of traits. Tesfa\u2019s recent approval for release illustrates the success of the project and marks a milestone as it is the first variety (of many in the pipeline) to be released

    Efficiency of In Vitro Regeneration is Dependent on the Genotype and Size of Explant in Tef [Eragrostis tef (Zucc.) Trotter]

    Get PDF
    Tef [Eragrostis tef (Zucc.) Trotter] is the major cereal crop in the Horn of Africa particularly in Ethiopia where it is staple food for about 50 million people. Its resilience to extreme environmental conditions and high in nutrition makes tef the preferred crop among both farmers and consumers. The efficiency of in vitro regeneration plays significant role in the improvement of crops. We investigated the efficiency of regeneration in 18 tef genotypes (15 landraces and three improved varieties) using three sizes of immature embryos (small, intermediate and large) as an explant. In vitro regeneration was significantly affected by the genotype and the size of the immature embryo used as a donor. Intermediate-size immature embryos which were 101-350 µm long led to the highest percentage of regeneration. Interestingly, the three improved varieties presented very low regeneration efficiencies whereas the landrace Manyi resulted in consistently superior percentage of in vitro regeneration from all three sizes of explants. The findings of this work provide useful insight into the tef germplasm amenable for the regeneration technique which has direct application in techniques such as transformation. It also signifies the importance of using tef landraces instead of improved varieties for in vitro regeneration

    Identification of Drought Tolerant Mutant Lines of Tef [Eragrostis tef (Zucc.) Trotter]

    Get PDF
    Introduction: Tef [Eragrostis tef (Zucc.) Trotter] is the major food crop in Ethiopia where it is annually cultivated on about 30% of the total area allocated to cereals. The productivity of tef is, however, significantly reduced by drought which can occur at either the early or the late developmental stage of the crop. Methodology: A total of 10,000 EMS (ethyl methane sulfonate) mutagenized M2 tef populations were screened first for early and second for terminal drought tolerance. The performance of candidate lines was investigated using diverse agronomical and physiological parameters. Results and discussion: Several promising lines were obtained for both early and terminal drought tolerance. Among these, genotypes with outstanding performance were found for two drought tolerant tef lines targeting early drought tolerance (dtt2 and dtt13) and three terminal drought tolerant lines targeting terminal drought tolerance (tdt9, tdt15 and tdt19). Conclusions: Candidate lines for both early and terminal drought tolerance will play vital roles in deve- loping drought tolerance in tef improvement

    Identification of miRNAs linked with the drought response of tef [Eragrostis tef (Zucc.) Trotter]

    No full text
    Tef [Eragrostis tef (Zucc.) Trotter], a staple food crop in the Horn of Africa and particularly in Ethiopia, has several beneficial agronomical and nutritional properties, including waterlogging and drought tolerance. In this study, we performed microRNA profiling of tef using the Illumina HiSeq 2500 platform, analyzing both shoots and roots of two tef genotypes, one drought-tolerant (Tsedey) and one drought-susceptible (Alba). We obtained more than 10 million filtered reads for each of the 24 sequenced small cDNA libraries. Reads mapping to known miRNAs were more abundant in the root than shoot tissues. Thirteen and 35 miRNAs were significantly modulated in response to drought, in Alba and Tsedey roots, respectively. One miRNA was upregulated under drought conditions in both genotypes. In shoots, nine miRNAs were modulated in common between the two genotypes and all showed similar trends of expression. One-hundred and forty-seven new miRNA mature sequences were identified in silico, 22 of these were detected in all relevant samples and seven were differentially regulated when comparing drought with normal watering. Putative targets of the miRNA regulated under drought in root and shoot tissues were predicted. Among the targets were transcription factors such as CCAAT-HAP2, MADS and NAC. Verification with qRT-PCR revealed that five of six potential targets showed a pattern of expression that was consistent with the correspondent miRNA amount measured by RNA-Seq. In general, candidate miRNAs involved in the post-transcriptional regulation of the tef response to drought could be included in next-generation breeding programs

    Tef (Eragrostis tef) Variety ‘Tesfa’

    No full text
    ጤፍ በኢትዮጵያ ከሚመረቱ የብርዕና አገዳ ሰብልች ዋናው ሲሆን የዓመቱ ቁጥር ከ6.5 ሚሉዮን የማያንስ አርሶ አዯር ያመርተዋሌ፡፡ ይህም አጠቃሊይ በብርዕና አገዳ ሰብልች ከሚሸፈነው ማሳ 30% ድርሻ አሇው፡፡ ይሁን እንጂ ከላልች ሰብልች ጋር ሲነፃፀር ምርታማነቱ አነስተኛ ነው፡፡ ሇዚህም ምክንያቱ በከፊሌ አርሶ አዯሩ ያሌተሻሻለ የአካባቢ ዝርያዎችን በመጠቀሙና፣ የሰብለ ተፈጥሯዊ የመጋሸብ ባህሪ ናቸው፡፡ የዚህ ጥናት ዓሊማ በተሇየ ምርምር አሰራር የተገኘን የጤፍ ዝርያን በመፈተሸ የተሻሇ ምርት፤ የአገዳ ጥንካሬን አንዲሁም የዘር ቀሇም ያሇውና በአርሶ አዯሩ ተመራጭ ዝርያ ማፍሇቅ ነበር፡፡ በጥናቱ በቅርቡ የተሇቀቀ አንድ ዝርያና አንድ የአካባቢ ዝርያን ጨምሮ 10 የተሇያዩ የጤፍ አይነቴዎችን በማካተት በስድስት ወካይ ጤፍ አብቃይ ቦታዎች ሊይ ተፈትሸው ተስፋ (ዯዘ-ክሮስ-457) ተብል የተሰየመውና የተሇያዩ የጤፍ አይነቴዎች ተዳቅሇው የተገኘው ዝርያ ከላልች ማወዳዯሪያ ተፈታሽ ዝርያዎች የተሻሇ ውጤት በማስመዝገቡ በብሄራዊ የዝርያ አፅዳቂ ኮሚቴ ተገምግሞ ሇምርት እንዲሇቀቅ ተወስኗሌ፡፡ ይህ ዝርያ ከላልች ዝርያዎች በንፅፅር መጋሸብን በመቋቋሙ፤ የተሻሇ ምርት በመስጠቱ በአርሶአዯሩ ተፈሊጊ ከመሆኑም በሻገር ከዝርያው ባህሪ የተነሳ ሇመስኖ እርሻና በሰብሌ መድረሻ ጊዜ የማጨጃ የእርሻ መሳሪያ መጠቀም ያስችሊሌ፡፡Tef [Eragrostis tef (Zucc.) Trotter] is extensively cultivated cereal crop in Ethiopia where it is annually grown by about 6.5 million smallholder farmers on about 30% of the total area allocated to cereal crops.However, the productivity of tef is very low compared to other cereals mainly due to lack of high yielding and lodging tolerant cultivars. The objective of this study was to evaluate the performance of the recently released tef variety called Tesfaand to provide unique morphological and agronomic descriptions of this new variety. Ten genotypes which were derived from three independent crosses and bred for at least eight generations plus a local and standard check varieties were tested at six tef growing sites in Ethiopia (namely, Adet, Chafe Donsa,DebreZeit black soil, DebreZeit light soil,Ginchiand Holetta) using RandomizedCompleteBlock Design with three replications. The study found that Tesfa(DZ-Cr-457 RIL-181) which was obtained from a cross between kinde (a semi-dwarf mutant line developed at the University of Bern, Switzerland) and Kay Murri(a landrace) outperformed other genotypes and approved for release by the Ethiopian National Variety Release Committee in March 2017.The main advantages of Tesfa over other tested lines were its higher grain yield and higher lodging tolerance. In addition, Tesfa possesses unique properties for which high acceptance by growers is expected. These are its compact panicle, lack of shattering, and thick and strong cul
    corecore