1,721,006 research outputs found
Enhancing Erucic Acid and Wax Ester Production in Brassica carinata through Metabolic Engineering for Industrial Applications
No full textMetabolic engineering enables oilseed crops to be more competitive by having more attractive properties for oleochemical industrial applications. The aim of this study was to increase the erucic acid level and to produce wax ester (WE) in seed oil by genetic transformation to enhance the industrial applications of B. carinata. Six transgenic lines for high erucic acid and fifteen transgenic lines for wax esters were obtained. The integration of the target genes for high erucic acid (BnFAE1 and LdPLAAT) and for WEs (ScWS and ScFAR) in the genome of B. carinata cv. ‘Derash’ was confirmed by PCR analysis. The qRT-PCR results showed overexpression of BnFAE1 and LdPLAAT and downregulation of RNAi-BcFAD2 in the seeds of the transgenic lines. The fatty acid profile and WE content and profile in the seed oil of the transgenic lines and wild type grown in biotron were analyzed using gas chromatography and nanoelectrospray coupled with tandem mass spectrometry. A significant increase in erucic acid was observed in some transgenic lines ranging from 19% to 29% in relation to the wild type, with a level of erucic acid reaching up to 52.7%. Likewise, the transgenic lines harboring ScFAR and ScWS genes produced up to 25% WE content, and the most abundant WE species were 22:1/20:1 and 22:1/22:1. This study demonstrated that metabolic engineering is an effective biotechnological approach for developing B. carinata into an industrial crop
Micropropagation, transformation and genetic diversity of Hagenia abyssinica (Bruce) J.F. Gmel.
Get PDFThe tree species Hagenia abyssinica belongs to a monotypic genus in the family Rosaceae. It grows on the highlands of tropical Africa, where it is seriously endangered principally due to high timber demands. Therefore, the establishment of fast and efficient biotechnological methods to propagate and improve different traits of interest is much needed. The objectives of this study were to establish micropropagation and in vitro regeneration protocols and to transform this species with the rolB gene to improve the rooting efficiency. In addition, a study of genetic diversity was needed to provide information for in situ and ex situ conservation. A micropropagation protocol has been developed using explants from both juvenile and mature tree sources. These explants were initiated, multiplied and rooted using either WPM or MS medium and different combinations of BAP and IBA. Using leaves from in vitro grown shoots of juvenile or mature tree origin, an in vitro regeneration protocol has been developed based on using TDZ alone or in combination with NAA or 2,4-D. Regeneration efficiency was also studied using TDZ or BAP in combination with IAA. The effects of wounding, kanamycin and cefotaxime on regeneration have been studied. TDZ was found to be the best cytokinin for regeneration of H. abyssinica at low concentrations since it promotes direct shoot regeneration, as well as at high concentrations since it promotes callus induction and shoot regeneration although it inhibits shoot elongation. All auxins appeared to be toxic to H. abyssinica, particularly at higher concentrations. Based on the results of these regeneration experiments, H. abyssinica was transformed with the rolB gene. One clone of the transformants exhibited 77% rooting while no roots were produced by any of the untransformed control shoots. Kanamycin was found to be the main factor inhibiting the recovery of transformants whereas cefotaxime is toxic only at high concentrations. Since somaclonal variation of micropropagated plants is highly undesirable, genetic stability was tested on 80 micropropagated plants, 40 of axillary origin and 40 from adventitious shoots. These plants had been grown in vitro for over two years when they were screened with randomly amplified polymorphic DNA (RAPD) markers. Only one plant, originating from an axillary shoot, deviated by showing two extra bands thus indicating that H. abyssinica is relatively stable in vitro. A genetic diversity study based on inter simple sequence repeats (ISSR) was conducted on a total of 120 samples representing 12 populations from different parts of Ethiopia. This study showed that within- and between-population variability in H. abyssinica is typical of an outcrossed, perennial, late-successional species. Two recently planted populations and one indigenous primary forest-population showed the highest diversity. An autocorrelation analysis between genetic and geographic distances indicated that gene flow takes place over only about 30 km and this is likely to decrease even further because of genetic isolation among populations brought about by the current logging practices
In vitro propagation of Ximenia americana L. from shoot tip explants: a multipurpose medicinal plant
No full textXimenia americana L. is among the most important multipurpose medicinal plants.It is highly vulnerable plant in Ethiopia due to overexploitation for different purposes, especially using the roots and barks for medicinal purposes.Seed germination is very poor and identical clones of superior quality plants cannot be obtained in nature as it is dioecious species. Therefore, the objective of this study was to develop in vitro propagation protocol for X. americana. After seed sterilization and germination, shoot tips from in vitro germinated seeds were cultured on ms (Murashige and Skoog) medium supplemented with different concentrations of benzyl amino purine (bap) or kinetin. For shoot multiplication, the initiated shoots were cultured on ms medium containing different concentrations of kinetin or bap in combination with a-naphthalene acetic acid (naa). Multiplied shoots were cultured on half strength ms medium supplemented with different concentrations of indole butyric acid (iba) or naa for rooting. The highest mean shoot number per explant (4.16 ± 0.17) was obtained on msmedium supplemented with 0.5 mg/l bap. The best rooting was obtained on half strength ms medium supplemented with 0.5 mg/l iba with 3.36 ± 0.69 roots per shoot and 2.21 ± 0.40 cm root length on medium containing 2.0 mg/l iba and established in greenhouse with 100% survival. The results of this study are important for mass propagation of superior genotypes, rehabilitation in natural habitat and conservation of this threatened multipurpose plant
Effect of growth regulators concentrations on in vitro multiplication of three elite sugarcane (Saccharum officinarum L.) Genotypes using shoot tip culture
Get PDFConventional vegetative propagation of sugarcane generally has low multiplication rate and allows distribution of diseases. Micropropagation is the only practical means of achieving rapid, large-scale production of disease-free quality planting material. Experiments on shoot tip culture initiation and shoot multiplication were laid out in completely randomized design with 2x3x3 and 4x5x3 factorial treatment arrangements respectively. Data were subjected to analysis of variance (ANOVA) and significant means were separated using Duncan's multiple range tests. With regard to shoot multiplication, genotype Q200 showed a maximum of 13.59 shoots per explant with 5.83cm shoot length on a medium fortified with 2 mg/l BAP alone, while genotype Q217 produced a maximum of 15.28 shoots per explant with 5.37cm mean shoot length on a medium supplied with 2.0 mg/l BAP and 0.25 mg/l kinetin. Likewise, Co-0238 produced a maximum of 13.56 shoots per explant with a mean shoot length 6.50 cm on medium fortified with 1.5 mg/l BAP + 0.5mg/l kinetin
Phenotypic diversity of enset (Ensete ventricosum (Welw.) Cheesman) landraces used in traditional medicine
Get PDFEnset (Ensete ventricosum (Welw.) Cheesman) is a multipurpose food security crop extensively cultivated in southern and southwestern parts of Ethiopia. In addition to its wide consumption as a source of food and feed, some enset landraces are also used as a traditional medicine in some parts of the country. However, the latter are becoming vulnerable to various human-related activities and environmental constraints. The main objective of this study was, therefore, to investigate the diversity that exist in enset landraces used for traditional medicine. A field study was conducted in four Administrative Zones and one special District in the Southern Nations, Nationalities and Peoples Region in Ethiopia. A total of 14 qualitative traits were employed to investigate the diversity in 40 landraces through field observation, color charts and focus group discussion. The data were analyzed using SAS and MINITAB softwares. Principal component analysis showed that the first four principal components accounted for 77% of the total variations and classified the landraces into four distinct groups. Similarly, cluster analysis grouped the landraces into four major clusters each containing 4–15 landraces. In general, the 14 phenotypic traits used in this study are important in discriminating the landraces indicating the existence of high genetic diversity among the landraces which needs to be conserved for the future
Micropropagation of Glinus Lotoides L.: An Endangered Medicinal Plant
Get PDFGlinus lotoides L., an endangered medicinal herb, is valued for its dietary vegetable and medicinal properties. It is propagated by seed. However, the seeds remain viable for very short period of time resulting in scarce distribution throughout the world. Hence, the objective of this study was to enhance germination of the seeds and to develop a micropropagation protocol for this plant. For seed germination experiment, Plant Growth Regulator (PGR) free MS (Murashige and Skoog) medium, filter paper and potted soil were used. Freshly harvested seeds from green house were sowed in PGR free MS medium to serve as explants. MS media containing different concentrations of 6-Benzyl Amino Purine (BAP) and Kinetin (KIN) were used for culture initiation and multiplication. Root induction was done on half strength MS medium containing different concentrations of Indole-3-Butyric Acid (IBA). Maximum ex vitro germination (73.77%) was obtained from fresh (0- day- old) seeds. The highest germination response (73.55%) was obtained from fresh (0- day- old) seeds sowed on MS medium. Highest shoot initiation (98.11%) was observed on medium containing 0.5 mg/l BAP. Best shoot multiplication (8.82 shoots per explant) was achieved on MS medium containing 0.5 mg/l BAP. Maximum shoot height (2.20 cm) was attained on PGR-free MS medium. Highest root number per shoot (6.86) with 96.67% rooting response was obtained in the presence of 0.5 mg/l IBA. Maximum root length (4.06 cm) was also achieved on this medium. The plantlets were transferred to sand-red soil-compost in 2:1:1 ratio and 87% of the plantlets survived after acclimatization. Thus, this study is useful for micropropagation of this medicinally important species. Keywords: Acclimatization, Rooting, Seed germination, Shoot multiplicatio
Micropropagation of Moringa oleifera Lam. from shoot tip explants
No full textMoringa oleifera Lam. is one of the most important plants that serve as medicinal and functional food. It is found in very limited areas in Ethiopia and traditional propagation is by seeds where it is difficult to get uniform plants of superior genotypes. The objective of this study was to develop efficient in vitro propagation protocol of M. oleifera from shoot tip. Seeds of M. oleifera were sterilized with calcium hypochlorite. The sterilized seeds were germinated on growth regulators free Murashige and Skoog (MS) medium. Shoot tips of M. oleifera were excised from in vitro grown seedlings and cultured on MS medium supplemented with 0.5 mg/l kinetin or 6-benzylaminopurine (BAP). The initiated shoots were transferred to shoot multiplication medium containing different concentrations of BAP in combination with indole butyric acid (IBA) or kinetin. The multiplied shoots were transferred to half strength MS medium containing different concentrations of IBA in combination with α-naphthalene acetic acid (NAA) for rooting. Seeds sterilized with 10% calcium hypochlorite for 30 min showed 100% germination. All cultured shoots were initiated and the highest shoot number per explant (5.66±0.44) was obtained on MS medium supplemented with 1.0 mg/l BAP in combination with 0.5 mg/l IBA and 94% of shoots rooted on half strength MS supplemented with 0.25 mg/l NAA. After acclimatization, 90% of plants survived. This in vitro propagation protocol can be used for clonal propagation of superior genotypes of this tree plant in short period of time contributing to its conservation and genetic improvement
In Vitro Regeneration of Sweet Potato (Ipomoea Batatas (L.) Lam.) Convolvulaceae, From Leaf and Petiole Explants
No full textBiotic stresses are the major constraints that result in total lossof sweet potato (Ipomoea batatas (L.) Lam.) yield. The establishment of invitro regeneration protocol for this plant is essential to improve it throughtissue culture and genetic engineering. The objective of this study was toestablish in vitro regeneration protocol for sweet potato varieties Beletechand Awassa-83 using leaf and petiole explants. MS medium containingdifferent concentrations of 2,4-D and kinetin were used to evaluate theireffect on callus induction whereas different concentrations of BAP were usedto evaluate its effect on shoot regeneration from callus. BAP alone or incombination with GA3 was used to evaluate their effect on shootmultiplication whereas IBA was evaluated for its effect on rooting. Thehighest percentage of callus induction (93%) was obtained from petioleexplants of both varieties on MS medium containing 0.05 mg/l 2,4-D incombination with 0.5 mg/l kinetin. The highest percentage of shootregeneration from leaf explants was obtained on growth regulators-free MSmedium while the best regeneration from petiole explants was obtained onMS medium supplemented with 1.0 mg/l BAP in both varieties. The highestnumber of shoots per node (2.40 ± 0.11) was obtained on MS mediumcontaining 1.0 mg/l BAP from shoots originally obtained from callus of leafexplants of Awassa-83. All shoots cultured on MS media containing differentconcentrations of IBA and the growth regulators-free medium resulted in100% rooting. After one month of acclimatization, more than 90% ofplantlets survive
In vitro regeneration of Moringa Oleifera lam. from leaf explants
No full textMoringa oleifera Lam. is the most important tree because every part of the plant has nutritional and medicinal use. As a tree plant, it is difficult to improve this plant by traditional breeding. Biotechnological approaches are useful for its genetic improvement. Therefore, the objective of this study was to develop in vitro regeneration protocol for Moringa oleifera by using leaf explants. Young leaves from in vitro multiplied shoots were excised, wounded and cultured on ms medium supplemented with different concentrations of bap in combination with naa for callus induction. For shoot regeneration, the calli were cultured on ms medium supplemented with bap (0.0, 0.5, 1.5, 2.0mg/l) in combination with naa (0.0, 0.5, 1.5, 2.0, 2.5, 3.0 mg/l). Multiplication of regenerated shoots was done on MS medium supplemented with bap (0.0, 0.5, 1.0, 1.5, 2.0 mg/l) in combination with IBA (0.0, 0.5, 1.5, 2.5, 3.5 mg/l). For rooting, shoots were cultured on half strength ms medium containing 0.0, 0.5, 1.5, 2.0, 2.5, mg/l naa or 0.0, 0.5, 1.0, 2.0, 3.0 mg/l iba. The highest percentage of callus induction (73.3%) and shoot regeneration from callus (33.3%) were obtained on the ms medium supplemented with 0.5 mg/l bap and 0.5 mg/l naa, respectively. The highest mean shoot (3.13±0.73) and root (9.60±0.86) number per explant were obtained on medium containing1.0 mg/l bap and 0.5 mg/l iba, respectively. After acclimatization, 90% plants survived in greenhouse. This protocol can be used for genetic improvement of this tree species through genetic transformation and somaclonal selection
In vitro Production of Virus-Free Sweet Potato [Ipomoea batatas (L.) Lam] by Meristem Culture and Thermotherapy
Get PDFViral disease is the major factor causing significant yield loss in sweet potato. Production of disease-free clones by tissue culture technique increases yield and income of farmers. Meristems from three varieties of sweet potato were cultured at different combinations of BAP, GA3 and NAA in MS basal medium. Among the combinations, 1 mg/l BAP and 1 mg/l GA3 with 0.01 mg/l NAA resulted in 66.67% shoot induction for Awassa-83 and Guntute while 63.33% shoot induction was obtained using 1 mg/l BAP, 2 mg/l GA3 and 0.01 mg/l NAA for Awassa local. There was 100% sweet potato virus elimination from all the three varieties by meristem culture as observed by using NCM-ELISA technique. Shoot thermotherapy was done for Awassa-83 and Awassa local at 37°C for 31 days and 88.89% and 100% SPFMV and SPCSV virus elimination was achieved for the two varieties, respectively. Best shoot multiplication was obtained in MS medium containing 2 mg/l BAP for Awassa-83 (5.26 ± 0.02 shoots/explant) and Awassa local (5.12 ± 0.02 shoots/explant). For Guntute it was 2.48 ± 0.03 shoots/explant on 3 mg/l BAP. The best root length was 9.5 ± 0.10 cm, 9.68 ± 0.02 cm, and 11.03 ± 0.02 cm for Awassa-83, Awassa local and Guntute, respectively on growth regulators free ½ MS medium. The highest number of roots per shoot (6.34 ± 0.01) was obtained from Awassa-83 on 0.1 mg/l IBA. Acclimatizations were 100%, 91.11% and 90.10% for Guntute, Awassa-83 and Awassa local, respectively. This work indicates the practical applicability of plant tissue culture using meristem culture and thermotherapy to produce virus-free planting materials of sweet potato
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