634 research outputs found
Genetic Variability, Stability and Inheritance of Grain Iron and Zinc Content in Pearl Millet (Penniserurn glaucum (L.) R. Br.)
The prcscnt study was undcrtakcn to determlnc thc niagnitudc of gcnctic v;~rlahtl~ly
for grain iron (Fe) and zinc (Zn) anlong a divcrsc rangc of hrccding lines, ~niprovc(l
populat~ons( anlong and withln populal~ons)a nd gcrniplasni acccssions; to assess thc
stabll~ty across different envlronnicnts; to cxanilnc thc rclationshlps hctwccn thcm and
with days to 50% flower and 1000-grain mass; and to determine the nalure of inhcr~tancc
and heritab~l~ty.
Over two-fold vanat~on was found for hoth gram Fc (30.1 75 7 mg kg I) and %n
content (24.5-64.8 my k g 1 )w ith medium to h~ghb road-scnsc hcr~tahilityi n diffcrcnt
classes of brccdtng materials and unproved populations (42.0 79.0 rng kg" Fc and
24.2-51.7 mg kg'' Zn), indicating large gcnctlc varlahllity for thc in~provcmcnt of gram Fe and Zn content and the scope for efiietive selection. The highest lcvels of Fc mid Zn
content were observed in well-adapted commercial varieties and in thc p:~rcnt;~lli nes of
released hybrids, which had large rnradr pmiplasrn base in their parentage, suggcstitig
[he possibility of making imrncdlalc impact on the nutritional security. Large u~lhlnpopulauon
variab~lity of ovcr two-fold for gram Fc (40.0 118.9 nip kg") and Zn
(31.8 82.7 mg kg") content was detcc~cdin pmgcntcs derived froni two open-poll~nated
varieties (AIMP 02901 and GU 8735). ttidicating possibility of sclcct~on withinpopulatton
and the prospects of enhancing gram Fe and Zn levels by recurrent sclectio~i.
The d~fference between the sunimer and ralny season for grain Fe and %n contcnt among
the entnes was largely due to thc soil Fe and Zn content of thc liclds ~lscil in Ihc
crpenments.
The pos~tive and highly significant correlation hetwccn Fe and %n contcnt in oll thc
expennicnts, ind~catcd the possibtlity of simultaneous gcnctlc iniprovcmcnt fbr the
elevated levels of both m~cronutricnts. Stgntlicnnt positive correlations of 1000-pr:lin
mass and negative correlation of days to 50% flower with Fc and %n contcnt suggcstcd
good prospects of combining high Fc and Zn w~thf amicrs-preferred tralts such i~sla rgc
seed sire atid carly ma~urity...........
Genetic dissection of grain zinc concentration in spring wheat for mainstreaming biofortification in CIMMYT wheat breeding
Wheat is an important staple that acts as a primary source of dietary energy, protein, and essential micronutrients such as iron (Fe) and zinc (Zn) for the world’s population. Approximately two billion people suffer from micronutrient deficiency, thus breeders have crossed high Zn progenitors such as synthetic hexaploid wheat, T. dicoccum, T. spelta, and landraces to generate wheat varieties with competitive yield and enhanced grain Zn that are being adopted by farmers in South Asia. Here we report a genome-wide association study (GWAS) using the wheat Illumina iSelect 90 K Infinitum SNP array to characterize grain Zn concentrations in 330 bread wheat lines. Grain Zn phenotype of this HarvestPlus Association Mapping (HPAM) panel was evaluated across a range of environments in India and Mexico. GWAS analysis revealed 39 marker-trait associations for grain Zn. Two larger effect QTL regions were found on chromosomes 2 and 7. Candidate genes (among them zinc finger motif of transcription-factors and metal-ion binding genes) were associated with the QTL. The linked markers and associated candidate genes identified in this study are being validated in new biparental mapping populations for marker-assisted breeding
Impact of soil moisture and plant population on yield components and yield of maize (Zea mays)
Experiment was conducted with three water levels such as 100, 75 and 50 % with three spacing, viz. normal, narrow and reduced narrow spacing of maize. Reducing the plant spacing, enhanced the plant population per unit area which increases maize yield even under reduced soil moisture level. Individual treatments of normal irrigation practice, narrow plant spacing and its interaction registered better performance of kernel, stover yield and yield attributes
Ordering of binary colloidal crystals by random potentials
Structural defects are ubiquitous in condensed matter, and not always a nuisance. For example, they underlie phenomena such as Anderson localization and hyperuniformity, and they are now being exploited to engineer novel materials. Here, we show experimentally that the density of structural defects in a 2D binary colloidal crystal can be engineered with a random potential. We generate the random potential using an optical speckle pattern, whose induced forces act strongly on one species of particles (strong particles) and weakly on the other (weak particles). Thus, the strong particles are more attracted to the randomly distributed local minima of the optical potential, leaving a trail of defects in the crystalline structure of the colloidal crystal. While, as expected, the crystalline ordering initially decreases with an increasing fraction of strong particles, the crystalline order is surprisingly recovered for sufficiently large fractions. We confirm our experimental results with particle-based simulations, which permit us to elucidate how this non-monotonic behavior results from the competition between the particle-potential and particle-particle interactions
Micronuclei to detect in vivo chemotherapy damage in a p53 mutated solid tumour
Apoptosis induction and micronuclei formation were compared following cytotoxic treatments in two rat glioma differing in p53 integrity. In vitro, micronuclei emergence but not apoptosis was linked to the p53 mutated status. In vivo, micronuclei assays were more sensitive to evaluate DNA damage induced by chemotherapy in a p53-mutated solid tumour.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe
Genetic dissection of zinc, iron, copper, manganese and phosphorus in wheat (Triticum aestivum L.) grain and rachis at two developmental stages
The development of high-yielding wheat genotypes containing micronutrient-dense grains are the main prio- rities of biofortification programs. At the International Maize and Wheat Improvement Center, breeders have successfully crossed high zinc progenitors including synthetic hexaploid wheat, T. dicoccum, T. spelta and landraces to generate high-zinc varieties. In this study, we report a genome-wide association using a wheat diversity panel to dissect the genetics controlling zinc, iron, copper, manganese and phosphorus concentrations in the grain and rachis during grain development and at physiological maturity. Significant marker-trait associations (MTAs) were identified for each nutrient using multi-locus mixed model methodologies. For mature grain, markers that showed significant pleiotropic effects were found on chromo- somes 1A, 3B and 5B, of which those on chromosome 5B at ∼95.5 cM were consistent over two growing seasons. Co-located MTAs were identified for the nutrient concentrations in developing grain, rachis and mature grain on multiple chromosomes. The identified genomic regions included putative candidate genes involved in metal uptake and transport and storage protein processing. These findings add to our understanding of the genetics of the five important nutrients in wheat grain and provide information on genetic markers for selecting high mi- cronutrient genotypes.Suong T. Cua, Georgia Guilda, Alison Nicolsona, Govindan Velub, Ravi Singhb, James Stangouli
Variability for grain iron and zinc contents in pearl millet hybrids
Dietary deficiency of mineral micronutrients such as iron
(Fe) and zinc (Zn) has been recognized as a worldwide
human health problem, especially in the developing
countries (Welch and Graham 2004). The pearl millet
(Pennisetum glaucum) research program at the International
Crops Research Institute for the Semi-Arid Tropics
(ICRISAT) has undertaken to address this issue through
the development of improved breeding materials with the
elevated levels of these micronutrients for eventual use in
cultivar development. Pearl millet, grown on 26 million
ha in some of the most marginal arid and semi-arid
tropical environments of Asia (11 million ha) and Africa
(15 million ha), is a major source of dietary energy and
nutritional security for a vast population in these regions
PP-116 Profile of occult hepatitis B virus infection in an area with intermediate prevalence of HBV infection
The Virulence in the Guinea-pig of Tubercle Bacilli Isolated before Treatment from South Indian Patients with Pulmonary Tuberculosis 3. Virulence related to Pretreatment Status of Disease and to Response to Chemotherapy
This is the last of a series of three reports from the Tuberculosis Chemotherapy Centre
Madras, on a study undertaken with the object of finding out whether differences in the
virulence in the guinea-pig of tubercle bacilli isolated from South Indian tuberculous patients
before the start of chemotherapy are related to the severity of the patients’ disease on
admission to treatment and to the subsequent response to chemotherapy. The 281 patients in
this study were drawn from the patients admitted to a l-year comparison of four domiciliary
chemotherapeutic regimens : (a) 3.9-5.5 mg/kg isoniazid plus 0.2-0.3 g/kg sodium PAS daily,
divided into two doses (PH series) ; (b) 7.8-9.6 mg/kg isoniazid alone daily in one dose
(HI-I series) ; (c) 7.8-9.6 mg/kg isoniazid alone daily, divided into two doses (HI-2 series) ;
(d) 3.9-5.5 mg/kg isoniazid alone daily, divided into two doses (H series).
No evidence was found of an association between the virulence of the organisms and
any pretreatment condition of known prognostic importance. There was no association
between pretreatment virulence and progress during treatment in the PH series (the most
effective regimen). In the other series, however, the progress was more satisfactory in
patients infected with organisms of low virulence than in those infected with organisms of
high virulence, the association between virulence and progress attaining statistical significance
in the combined HI-2 and H series (the least effective regimens) and only just
failing to do so in the smaller HI-1 series.
Possible explanations are put forward both for the absence of an association between
virulence and severity of disease on admission and for the presence of an association
between virulence and response in the patients treated with isoniazid alone
Adaptation and quality traits of a germplasm-derived commercial seed parent of pearl millet
Iniadi landrace germplasm of pearl millet (Pennisetum glaucum (L.) R. Br.) has typical characteristics of relatively photoperiod-insensitive early maturity and large seed size of dark grey colour. Direct selection within an iniadi landrace population from northern Togo led to the development of an early-maturing and high-yielding open-pollinated variety ICTP 8203, which is highly resistant to downy mildew (Sclerospora graminicola (Sacc.) Schroet). It has been under cultivation in India since 1989. During the course of the development of this variety, an S2 progeny was found to be a maintainer of the A1 cytoplasmic-nuclear male sterility system. Further inbreeding and selection in this progeny concurrent to its backcrossing into the sterility-inducing cytoplasm led to the development of maintainer line 863B and its male-sterile counterpart 863A, which is a seed parent of three commercial hybrids in India. Studies conducted in the past six years have shown this large-seeded line to have a unique combination of several useful traits, including high levels of resistance to multiple pathotypes of downy mildew, tolerance to terminal drought, high stover quality attributes, and high levels of grain iron and zinc contents. Quantitative trait loci (QTLs) with favourable alleles for downy mildew resistance, drought tolerance and various fodder quality attributes in this line have been identified, which further enhance its breeding value
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