48 research outputs found
Regeneration of Sudanese maize inbred lines and open pollinated varieties
Eight maize inbred lines and three open pollinated varieties from Sudan were evaluated for their response to tissue culture. Immature embryos obtained 16 days after pollination were used as explants for callus induction. Calli were induced on LS medium supplemented with 2 mg/L 2,4-dichlorophenoxyacetic acid. Callus induction capacity was highest in inbred lines IL3, IL15 and IL1. The Varieties Hudiba-2 and Hudiba-1 were not statistically different (p >0.05) in callus induction. Thecapacity for embryogenic callus formation was highest in inbred line IL3 followed by IL1 and IL38 and in varieties Hudiba-2 and Hudiba-1. Inbred lines IL16, IL42, IL43 and IL28 had the lowest embryogeniccallus formation capacity. Plant regenerating genotypes were IL3, IL38, IL15, IL1, Hudiba-2 and Mojtamaa-45. Inbred line IL3 was the most regenerable genotype with a shoot formation frequency of 76% averaging 6 shoots per callus. The highest regenerating variety was Mojtamaa-45, which averaged 5 shoots per callus
Transformation and Regeneration Protocol for Two Farmer Preferred Open Pollinated Tropical Maize (Zea Mays) Varieties
Article PurchasedAbstract: In vitro regeneration of open pollinated varieties (OPVs) Kakamega Striga Tolerant Population 94 (KSTP’94) and ‘Namba Nane’ alongside a tropical inbred line (CML144) was evaluated using immature zygotic embryos as explants. Four callus induction media (CIM) regimes; Murashige and Skoog (MS), Linsmaier and Skoog (LS), Chu (N6) and N6*(N6
medium fortified with 0.35 gL-1 L-proline and 0.8 mgL-1 AgNO3) were evaluated for their potential to induce callus in the three genotypes. All the media were supplemented with sucrose and five levels of 2, 4-Dichlorophenoxyacetic acid (2, 4-D) (0.5, 1.0, 1.5, 2.0 and 2.5 mgL-1). Resulting calli were matured on MS and N6 basal media supplemented with 60 g/L sucrose and similar concentration levels (0.5, 1.0, 1.5, 2.0 and 2.5 mgL-1) of 2, 4-D while the subsequent embryogenic calli were regenerated on hormone-free media. Transformability of these varieties was assessed via histochemical analysis of β-glucuronidase (GUS) reporter gene following Agrobacterium-mediated transformation. Statistical analyses were done using
Statistical Analysis Software (SAS) and Graphpad Prism softwares with mean separations achieved at 95% confidence intervals. Of the 2 OPVs, KSTP’94 recorded the highest callus induction frequency (84.4%) while Namba Nane (45.6%) had the lowest. Similarly, KSTP, 94 had the highest mean of mature somatic embryos (59.7%) while Namba Nane recorded the
lowest (16.4%). Assessment of regeneration frequencies from embryogenic calli revealed no significant differences among the
3 lines although CML 144 had the highest mean number of juvenile plantlets (36.7%). Analysis of transformation frequency
(upon selection of calli on media with basta) showed that Namba Nane recorded the lowest transformation frequency (average 13.5%) some words missing. Transformation frequency (based on GUS positive calli) of these varieties ranged from 0.8 to 2.1%. This work therefore provides an empirical platform for potential introduction of useful genes into these varieties
Efficient regeneration system for rapid multiplication of clean planting material of Ensete ventricosum (Welw.) Cheesman
Article purchased; Published online: 01 Dec 2017Enset (Ensete ventricosum (Welw.) Cheesman) is an economically important staple food crop in Ethiopia, especially in the southern and southwestern regions. It is called “false banana” due to its resemblance to banana, but inability to produce any edible fruit. The crop is clonally propagated using field-grown suckers. This study reports the development of a robust regeneration technique to propagate large numbers of plantlets using corm discs containing intercalary meristematic tissues. Hundreds of shoot buds were induced from corm discs of enset cultivar ‘Bedadeti’ cultured on Murashige and Skoog (MS) medium supplemented with 1.5 mg L−1 2,4-dichlorophenoxyacetic acid, 0.216 mg L−1 zeatin, and 2 g L−1 activated charcoal. The shoot buds were regenerated into complete plantlets when transferred onto MS medium supplemented with 1 mg L−1 6-benzylaminopurine and 2 g L−1 activated charcoal. More than 100 plantlets were generated in 4 mo from corm discs isolated from a single in vitro mother plantlet. Well-rooted plantlets were acclimatized in soil with 100% success, and did not show any apparent phenotypic abnormalities under glasshouse conditions. This efficient regeneration system could be very useful for the rapid multiplication of clean pathogen-free planting material
A simple and rapid protocol for the genetic transformation of Ensete ventricosum
Open Access Journal; Published online: 08 Nov 2019Enset (Ensete ventricosum), also known as Ethiopian banana, is a food security crop for more than 20 million people in Ethiopia. As conventional breeding of enset is very challenging, genetic engineering is an alternative option to introduce important traits such as enhanced disease resistance and nutritional value. Genetic transformation and subsequent regeneration of transgenic enset has never been reported mainly due to challenges in developing transformation protocols for this tropical species. Agrobacterium-mediated transformation could be a practical tool for the genetic improvement of enset. However, the efficiency of the transformation system depends on several parameters such as plant regeneration, genotype, explant, selection agent and Agrobacterium strains. As a first step towards the development of transgenic enset, a simple and rapid plant regeneration system was developed using multiple buds as explants. Induction and proliferation of multiple buds from shoot tip explants was achieved on Murashige and Skoog (MS) medium supplemented with 5 and 10 mg/l of 6-benzylaminopurine (BAP), respectively. Shoots were regenerated from multiple buds on MS media containing 2 mg/l BAP and 0.2% activated charcoal. Based on the optimized regeneration protocol, an Agrobacterium-mediated transformation method was developed using multiple buds as explants and the binary plasmid pCAMBIA2300-GFP containing the green florescent protein (gfp) reporter gene and neomycin phosphotransferase II (nptII) selection marker gene. Transgenic plantlets were obtained within 4 months at a frequency of about 1.25%. The transgenic lines were validated by PCR analysis using primers specific to the nptII gene. To obtain uniformly transformed plantlets, chimerism was diluted by subculturing and regenerating the transgenic shoots on a selective medium containing kanamycin (150 mg/l) for five cycles. The uniformity of the transgenic plants was confirmed by Southern blot hybridization and RT-PCR analyses on different tissues such as leaf, pseudostem and root of same transgenic plant. In the present study, we report a simple Agrobacterium-mediated transformation system for generating transgenic events of enset. To the best of our knowledge, this is the first report on the stable transformation and regeneration of transgenic events of enset. The transformation system established in this study can be used for the generation of transgenic enset with important traits such as disease resistance
Development of mobile sensors for estimation of grain qualities and contaminants to enhance nutrition and safety of grain-products in developing countries; current status
The governments of several developing countries responded to their population “malnutrition crisis” (P.Webb et al., 2018), among others, by promotion of crops of high nutritional value and their enhanced usage for food products formulations (e.g. “Millet Mission” in India or “Blending Policy” in Kenya). Simultaneously, several CGIAR crop improvement programs-initiated the development of nutritionally enhanced crop cultivars (e.g. ICRISAT, CIAT, IIT). In developing countries, the promotion of novel cultivars is generally a slow and tedious process, especially if the improved grain (quantity or quality) doesn’t ultimately result in the economic incentives (e.g. the market price). Thus far, there is no economic advantage directly linked to the trade of bio-fortified crop cultivars in developing countries which does prevents their accelerated adoption. This may change if/once the necessary information on a crops value is enabled
RECOVERY OF amiRNA3-PARP1 TRANSGENIC MAIZE PLANTS USING A BINARY VECTOR HAVING THE BIOSAFE PMI GENE
Positive plant selectable marker genes are commonly used in plant
transformation because they not only enhance the frequency of
generation transgenic tissues but are considered biosafe, unlike
antibiotic or herbicide resistance genes. In this study, the binary
vector pNOV2819-ubiamiRNA3PARP1, harbouring the phosphomannose
isomerase (pmi) gene was developed and used in recovery of transgenic
maize ( Zea mays L.) plants containing the drought tolerance gene,
amiRNA3-PARP1. The pre-amiRNA3-PARP1 and Tnos transgenes were
sequentially PCR-cloned upstream the ubiquitine promoter in the
Ubi/NC1300 plasmid. The pre-amiRNA3-PARP1 expression cassette was
transferred into the pmi gene-containing pNOV2819 plasmid to produce
the pNOV2819-ubiamiRNA3PARP1 vector. Transgenic IL3 and A188 plants
containing pre-amiRNA3-PARP1 were generated through transformation with
LBA4404 harbouring the pNOV2819-ubiamiRNA3PARP1 vector. The plants were
confirmed transgenic by PCR. It is clear that the developed vectors are
effective in recovery of amiRNA3-PARP1 transgenic tissues and plants
containing the pmi gene, which has been shown to have no negative
environmental or health effects.Les marqueurs g\ue9n\ue9tiques de s\ue9lection positive de
plantes sont commun\ue9ment utilis\ue9s dans la transformation des
plantes parce que, non seulement ils augmentent la fr\ue9quence de la
g\ue9n\ue9ration des tissus transg\ue9niques, mais aussi sont
consid\ue9r\ue9s comme biosains, \ue0 l\u2019inverse des
g\ue8nes de r\ue9sistance aux antibiotiques et herbicides. Dans
cette \ue9tude, le vecteur binaire pNOV2819-ubiamiRNA3PARP1 portant
le g\ue8ne isom\ue9rase phosphomannose (pmi) a \ue9t\ue9
d\ue9velopp\ue9 et utilis\ue9 dans le recouvrement
transg\ue9nique des plantes du ma\uefs ( Zea mays L.) contenant
le g\ue8ne to tol\ue9rance \ue0 la s\ue9cheresse amiRNA3-PARP1.
Les transg\ue8nes pre-amiRNA3-PARP1 et Tnos \ue9taient
s\ue9quentiellement clon\ue9s par PCR dans la partie
sup\ue9rieure du promoteur ubiquitine dans le plasmide Ubi/NC1300.
L\u2019expression de la cassette de la pr\ue9-amiRNA3-PARP1
\ue9tait transf\ue9r\ue9e dans le g\ue8ne pmi contenant le
plasmide pNOV2819 pour produire le vecteur pNOV2819-ubiamiRNA3PARP1.
Les plants transg\ue9niques IL3 et A188 contenant le
pre-amiRNA3-PARP1 \ue9taient g\ue9n\ue9r\ue9s \ue0 travers la
transformation avec LBA4404 portant le vecteur
pNOV2819-ubiamiRNA3PARP1. Les plants \ue9taient confirm\ue9es
transg\ue9niques par PCR. Il est clair que les vecteurs
d\ue9velopp\ue9s sont efficaces dans le recouvrement des tissus
transg\ue9niques amiRNA3-PARP1 et les plants contenant le g\ue8ne
pmi qui ne pr\ue9sentent aucun effet n\ue9gatif sur
l\u2019environnement et la sant\ue9
Cisgenesis and intragenesis as new strategies for crop improvement
Cisgenesis and intragenesis are emerging plant breeding technologies which offer great promise for future acceptance of genetically engineered crops. The techniques employ traditional genetic engineering methods but are confined to transferring of genes and genetic elements between sexually compatible species that can breed naturally. One of the main requirements is the absence of selectable marker genes (such as antibiotic resistance genes) in the genome. Hence the sensitive issues with regard to transfer of foreign genes and antibiotic resistance are overcome. It is a targeted technique involving specific locus; therefore, linkage drag that prolongs the time for crop improvement in traditional breeding does not occur. It has great potential for crop improvement using superior alleles that exist in the untapped germplasm or wild species. Cisgenic and intragenic plants may not face the same stringent regulatory assessment for field release as transgenic plants which is a clear added advantage that would save time. In this chapter, the concepts of cis/intragenesis and the prerequisites for the development of cis/intragenesis plants are elaborated. Strategies for marker gene removal after selection of transformants are discussed based on the few recent reports from various plant species
Globalization and Health: developing the journal to advance the field
Founded in 2005, Globalization and Health was the first open access global health journal. The journal has since expanded the field, and its influence, with the number of downloaded papers rising 17-fold, to over 4 million. Its ground-breaking papers, leading authors -including a Nobel Prize winner- and an impact factor of 2.25 place it among the top global health journals in the world. To mark the ten years since the journal’s founding, we, members of the current editorial board, undertook a review of the journal’s progress over the last decade. Through the application of an inductive thematic analysis, we systematically identified themes of research published in the journal from 2005 to 2014. We identify key areas the journal has promoted and consider these in the context of an existing framework, identify current gaps in global health research and highlight areas we, as a journal, would like to see strengthened
Current Nutrition and Health Situation in Kitui
This presentation provides a brief overview on the subject of malnutrition rates and desertification in Kitui, Kenya
Possible Channels for Distribution of HIV Oral Self-Test Kits in Kenya
The dataset contains the anonymized raw Stata data for the study "Possible Channels for Distribution of HIV Oral Self-Test Kits in Kenya." It also includes supporting documentation such as study questionnaires and interview guides. The unpublished report can be found here: http://www.3ieimpact.org/media/filer_public/2014/08/04/possible_channels_for_distribution-test_study_final_report.pd