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1.
Sci Rep ; 10(1): 7830, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385288

RESUMO

Rice (Oryza sativa L) is a most important staple food crop of the world because more than half of the World's population is dependent on it for their livelihood. Global rice production must be doubled by 2050 to cope up with the situation of population growth. Narrow genetic base in the released varieties has made the improvement in plateaus. Widening the genetic base is necessary to overcome the yield barrier. Hybridization and pre-breeding has been carried out to broaden the genetic base. Heritability and genetic advances were measured in the F5 lines (Tulaipanji × IR64), F3 lines (Tulaipanji × IR64 × PB1460), and F3 lines (Badshabhog × Swarna sub1). Some of the breeding lines were showing promising field performance with high yield potentiality. Wide crosses were performed to widen the genetic base between (Ranjit × O. rufipogon) and (Badshabhog × O. rufipogon) and the heritability pattern of the morphological characteristics in the progeny lines was evaluated. Nutritional quality of the rice grain is totally dependent on the morphology and histological characteristics of the caryopsis which are genetically determined. Caryopses ultrastructural analyses were carried out in seventeen different rice breeding lines through SEM. SEM analysis showed distinguishing ultrastructure in respect to pericarp, testa, aleurone layer, protein bodies and starchy endosperm in the breeding lines with distinctive inheritance pattern. This study provides information about the cross compatibility of the wide hybridization and heritability measures of the morphological traits which may supplement the breeding program to break the yield plateaus.


Assuntos
Cruzamento , Grão Comestível/genética , Oryza/genética , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Grão Comestível/crescimento & desenvolvimento , Humanos , Hibridização Genética/genética , Oryza/crescimento & desenvolvimento , Fenótipo , Proteínas de Plantas/genética
2.
Physiol Mol Biol Plants ; 23(1): 169-183, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28250593

RESUMO

Genetic diversity was assessed in the four orchid species using NGS based ddRAD sequencing data. The assembled nucleotide sequences (fastq) were deposited in the SRA archive of NCBI Database with accession number (SRP063543 for Dendrobium, SRP065790 for Geodorum, SRP072201 for Cymbidium and SRP072378 for Rhynchostylis). Total base pair read was 1.1 Mbp in case of Dendrobium sp., 553.3 Kbp for Geodorum sp., 1.6 Gbp for Cymbidium, and 1.4 Gbp for Rhynchostylis. Average GC% was 43.9 in Geodorum, 43.7% in Dendrobium, 41.2% in Cymbidium and 42.3% in Rhynchostylis. Four partial gene sequences were used in DnaSP5 program for nucleotide diversity and phylogenetic relationship determination (Ycf2 gene of Dendrobium, matK gene of Geodorum, psbD gene of Cymbidium and Ycf2 gene of Ryhnchostylis). Nucleotide diversity (per site) Pi (π) was 0.10560 in Dendrobium, 0.03586 in Geodorum, 0.01364 in Cymbidium and 0.011344 in Rhynchostylis. Neutrality test statistics showed the negative value in all the four orchid species (Tajima's D value -2.17959 in Dendrobium, -2.01655 in Geodorum, -2.12362 in Rhynchostylis and -1.54222 in Cymbidium) indicating the purifying selection. Result for these gene sequences (matK and Ycf2 and psbD) indicate that they were not evolved neutrally, but signifying that selection might have played a role in evolution of these genes in these four groups of orchids. Phylogenetic relationship was analyzed by reconstructing dendrogram based on the matK, psbD and Ycf2 gene sequences using maximum likelihood method in MEGA6 program.

3.
J Genet Eng Biotechnol ; 15(1): 275-286, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30647664

RESUMO

In this present study, we have described the diversity of nine Ocimum genotypes naturally grown in the Dakshin Dinajpur district of West Bengal, India. Their diversity was determined on the basis of morphological, chemical and randomly amplified polymorphic DNA (RAPD) to determine the level of variation present in the genus Ocimum. Among nine Ocimum genotypes six (O. americanum, O. × africanum, O. basilicum, O. gratissimum, O. kilimandscharicum and O. tenuiflorum) are found to be different Ocimum species and the rest are as varieties. A total of 18 qualitative and 17 quantitative morphological traits and chemical compositions were evaluated. Significant variations were observed in the morphological traits except O. × africanum and O. basilicum species. Cluster generated from the morphological data showed two different groups viz. basilicum group and sanctum group. Chemical analysis did not show much variation between morphologically similar species viz. O. × africanum and O. basilicum. However, RAPD analyses clearly showed that O. × africanum and O. basilicum are different species. Thus the combined analyses of morphological traits, chemical and molecular markers represent the best possible approach to confirm taxonomic delineation. Moreover, we are reporting O. × africanum for the first time from this region as well as from West Bengal, India.

4.
Physiol Mol Biol Plants ; 20(2): 209-24, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24757325

RESUMO

Genetic resources of landraces (84 cultivars) were collected from various agro-ecological regions of West Bengal and adjoining areas and characterized based on qualitative and quantitative agro-morphological descriptors along with zinc (Zn) and iron (Fe) content. The DUS protocol was employed to study 16 agro-morphological passport data such as: vegetative data (anthocyanin pigmentation, plant habit), reproductive data (flag leaf attitude, stigma colour, panicle attitude), including eight grain quality traits: grain length, grain width, 1000 grains weight, kernel length, kernel breadth etc. Highest seed weight was found in cultivar Khechri (32.04 g/1000 seeds), collected from Sundarban and least seed weight was 9.6 g/1000seeds in Katharibhog. Maturity duration was found very short (<100 days) in Jumla Marshi (97 days) collected from world's coldest rice growing area, Jumla, Nepal. Penultimate leaves breadth was observed broad (>2 cm) in one cultivar Jungli (2.3 cm). Seeds per panicle were 180 in Chinisakkar (medium range), 177 in Dudheswar, and 151 in Ladua. Flag leaf was found in erect condition in late observation in Dudheswar, Enda and Ghiosh. Seventeen cultivars were grouped in the aromatic rice category out of total 84 local landraces. Twenty-one cultivars were with awn, whose length ranges from 1.6 mm (Anandi) to 22.5 mm (Tulaipanji). Kernel colour varies from red, yellowish, brownish, creamy white to white. Kernel length varies from 4 mm to 8 mm and breadth 1.90 mm to 3 mm. Kernel length/breadth ration varied from 1.6 to 3.9. Highest ratio of L/B was found in Pusa Basmati 1(3.9) and lowest in Dudhey (1.6). Elongation ration was highest in Kalokure (2.07) and lowest in Phoolpakri (0.62). Nutritional values of mineral contents of iron (Fe) and zinc (Zn) were estimated in all cultivars by Atomic Absorption Spectrophotometic method. Iron concentration varies from 0.25 µg/g to 34.8 µg/g and zinc from 0.85 µg/g to 195.3 µg/g in the landraces. Highest iron containing rice was Swetonunia with 34.8 µg/g and highest amount of Zn was found in Nepali Kalam which was 195.3 µg/g. Anaerobic germination (AG) was observed in 18 cultivars among 84 land races (viz. Jungli, Kumrogore, Dudheshwar, Rambhog and Tulsi etc.), the trait is highly desired by the rice breeder for the introgression of this gene (QTL) to the HYV for direct seeding in the field for saving labour cost and reduced maturity time. Dendrogram showed genetic diversity among 84 landraces by grouping them into five major clusters. All the descriptors evaluated in this study have showed that there is enough genetic diversity among landraces and this information can be helpful to the breeders to choose the right parent for crop improvement.

5.
J Org Chem ; 76(17): 7229-34, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21793531

RESUMO

Titanocene(III) chloride (Cp(2)TiCl) mediated radical induced allylation of aldimines for the preparation of homoallyl amines is described. The radical was generated from the allyl bromide using Cp(2)TiCl as the radical source. Formal synthesis of C(4)-C(5')-linked 4'-deoxy aza-disaccharide is demonstrated and a study toward the bicyclic skeleton of alkaloids was also accomplished. The radical initiator Cp(2)TiCl was prepared in situ from commercially available titanocene dichloride (Cp(2)TiCl(2)) and Zn dust in THF under argon.


Assuntos
Aldeídos/química , Compostos Alílicos/química , Aminas/química , Compostos Aza/química , Dissacarídeos/química , Compostos Organometálicos/química , Alcaloides/química , Radicais Livres , Modelos Moleculares , Estrutura Molecular
6.
J Org Chem ; 70(20): 8252-4, 2005 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-16277363

RESUMO

[Chemical reaction: see text] A radical based Wagner-Meerwein-type rearrangement has been observed in camphoric systems. The radical was generated from the epoxide using Cp2TiCl as the radical source. The radical initiator Cp2TiCl was prepared in situ from commercially available Cp2TiCl2 and Zn dust in THF under argon.


Assuntos
Cânfora , Compostos de Epóxi/química , Compostos Organometálicos , Titânio , Radicais Livres , Indicadores e Reagentes , Modelos Moleculares , Conformação Molecular
7.
J Org Chem ; 67(10): 3242-8, 2002 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-12003531

RESUMO

Intramolecular radical cyclization of suitably substituted epoxy ethers 4a-g using bis(cyclopentadienyl)titanium(III) chloride as the radical source resulted in trisubstituted tetrahydrofurano lignans and 2,6-diaryl-3,7-dioxabicyclo[3.3.0]octane lignans depending on the reaction conditions. The titanium(III) species was prepared in situ from commercially available titanocene dichloride and activated zinc dust in THF. Upon radical cyclization followed by acidic workup, epoxy olefinic ethers 4a-g afforded furano lignans dihydrosesamin 1a, lariciresinol dimethyl ether 1b, acuminatin methyl ether 1e, and sanshodiol methyl ether 1g directly and lariciresinol 1h, acuminatin 1i, and lariciresinol monomethyl ether 1j after removal of the benzyl protecting group by controlled hydrogenolysis of the corresponding cyclized products. The furofuran lignans sesamin 2a, eudesmin 2b, and piperitol methyl ether 2e were also prepared directly by using the same precursors 4a-f on radical cyclization followed by treatment with iodine and pinoresinol 2h, piperitol 2i, and pinoresinol monomethyl ether 2j after controlled hydrogenolysis of the benzyl protecting group of the corresponding cyclized products. Two naturally occurring acyclic lignans, secoisolariciresinol 5h and secoisolariciresinol dimethyl ether 5b, have also been prepared by exhaustive hydrogenolysis of 2h and 2b, respectively.


Assuntos
Química Orgânica/métodos , Compostos de Epóxi/síntese química , Éteres Cíclicos/síntese química , Furanos/síntese química , Lignanas/síntese química , Alquilação , Catálise , Ciclização , Dioxóis/síntese química , Flavonoides/síntese química , Glicosídeos/síntese química , Lignina/síntese química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Estereoisomerismo
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