scholarly journals Pre-fertilization Barrier, Crossability and Meiotic Behavior of Interspecific Hybrids Among Brassica Species

2021 ◽  
Author(s):  
Usha Pant ◽  
Shikha Joshi ◽  
Preeti Lohani ◽  
Neha Dahiya
Keyword(s):  
Pollen Tube ◽  
Interspecific Hybrids ◽  
Brassica Species ◽  
Correlation Study ◽  
Plant Evolution ◽  
Pollen Parent ◽  
Phenotypic Characterization ◽  
Meiotic Abnormalities ◽  
Naturally Occurring ◽  
Specific Hybridization

Abstract Inter-specific hybridization is an important driving force in plant evolution, speciation and creation of novel genetic variations those are not available with the naturally occurring species. Present investigation includes study of pre-fertilization barriers, phenotypic characterization and the meiotic abnormalities during microsporogenesis in the interspecific hybrids. Mean pollen tube germination percent in interspecific hybrids was recorded to be highest in case of B. carinata x B. nigra (33.67±11.35) and lowest between B. carinata x B. napus (18.68±6.62) whereas in the reciprocal crosses it was highest for B. napus x B. carinata (33.06±13.41). Siliqua set ranged from 33% in B. carinata x B. napus to 72% in selfedB. carinata. Seed set % ranged from 0% in B. rapa x B. carinata and B.nigra x B.carinatato 25.64 % for B. carinata x B.nigra. Mean pollen tube growth was recorded highest in B. carinata x B. nigra (21.23±5.33) while was lowest in B. carinata x B. napus (10.18±3.17) and among reciprocals it was highest for B. nigra x B. carinata (21.39±7.53). Pollen tube abnormalities viz., coiling and bending of pollen tube, hairpin shaped pollen tube, swelling of tube tip, tube bifurcation, more than one tube emerging from pollen, tubes growing in wrong direction were observed. B. carinata as pollen parent showed highest mean pollen tube abnormality percent with B. napus (36.32±8.62) whereas lowest with B. nigra (18.09±6.73). It was observed highest with B. rapa (49.170 ±13.55) when B. carinata was used as pollen parent. Some of the pre fertilization barriers related to stylar and ovule region can also be observed through fluroscent microscopy. As per the observations B. carinata performed better as a seed parent with B. nigra, B. juncea and B. rapa whereas, with B. napus it performed good as a pollen parent. Correlation study gave the association the above traits with each other. The meiotic abnormalities showed improper alignment at M-I, M-II, A-I, A-II and Telophase.

scholarly journals Glucosinolate Content in Brassica Genetic Resources and Their Distribution Pattern within and between Inner, Middle, and Outer Leaves

Plants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1421
Author(s):  
Ju-Hee Rhee ◽  
Susanna Choi ◽  
Jae-Eun Lee ◽  
On-Sook Hur ◽  
Na-Young Ro ◽  
...  
Keyword(s):  
Genetic Resources ◽  
Defense Mechanism ◽  
Multiple Reaction Monitoring ◽  
Principal Component ◽  
Brassica Species ◽  
Glucosinolate Content ◽  
Proximal Half ◽  
Naturally Occurring ◽  
Low Concentrations ◽  
Entire Dataset

Glucosinolates (GSLs) are sulfur-containing secondary metabolites naturally occurring in Brassica species. The purpose of this study was to identify the GSLs, determine their content, and study their accumulation patterns within and between leaves of kimchi cabbage (Brassica rapa L.) cultivars. GSLs were analyzed using UPLC-MS/MS in negative electron-spray ionization (ESI−) and multiple reaction monitoring (MRM) mode. The total GSL content determined in this study ranged from 621.15 to 42434.21 μmolkg−1 DW. Aliphatic GSLs predominated, representing from 4.44% to 96.20% of the total GSL content among the entire samples. Glucobrassicanapin (GBN) contributed the greatest proportion while other GSLs such as glucoerucin (ERU) and glucotropaeolin (TRO) were found in relatively low concentrations. Principal component analysis (PCA) yielded three principal components (PCs) with eigenvalues ≥ 1, altogether representing 74.83% of the total variation across the entire dataset. Three kimchi cabbage (S/No. 20, 4, and 2), one leaf mustard (S/No. 26), and one turnip (S/No. 8) genetic resources were well distinguished from other samples. The GSL content varied significantly among the different positions (outer, middle, and inner) of the leaves and sections (top, middle, bottom, green/red, and white) within the leaves. In most of the samples, higher GSL content was observed in the proximal half and white sections and the middle layers of the leaves. GSLs are regarded as allelochemicals; hence, the data related to the patterns of GSLs within the leaf and between leaves at a different position could be useful to understand the defense mechanism of Brassica plants. The observed variability could be useful for breeders to develop Brassica cultivars with high GSL content or specific profiles of GSLs.

scholarly journals Development of an Intergenotypic Hepatitis C Virus (HCV) Cell Culture Method To Assess Antiviral Susceptibilities and Resistance Development of HCV NS3 Protease Genes from HCV Genotypes 1 to 6

2010 ◽  
Vol 84 (9) ◽  
pp. 4597-4610 ◽  
Author(s):  
Ingrid Imhof ◽  
Peter Simmonds
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Alternative Therapy ◽  
Culture Method ◽  
Response To Therapy ◽  
Phenotypic Characterization ◽  
Induced Mutations ◽  
Adaptive Mutations ◽  
Naturally Occurring

ABSTRACT Protease inhibitors (PIs) of hepatitis C virus (HCV) provide an additional or alternative therapy for chronic infection. However, assessment of their efficacy and ability to inhibit replication of different genotypes is hampered by the lack of a convenient animal model or a method for in vitro culture of HCV other than the type 1/2-based replicons and the infectious genotype 2a clone JFH1. To address this problem, we constructed a panel of replication-competent chimeric Jc1 (pFK JFH1/J6/C-846) clones containing protease and NS4A coding sequences from all six major genotypes, enabling the determination of replication and the susceptibility to PIs. Chimeras showed substantial variability in replication kinetics, attributable in part to naturally occurring polymorphisms and differing requirements for adaptive mutations in NS3 and NS4A. Through calculation of 50% inhibitory concentrations (IC50s) of BILN 2061, measuring reduction in the number of focus-forming units/ml (FFU/ml) and replication inhibition, consistent genotype-associated differences in antiviral susceptibilities were observed. IC50s for genotype 1b, 4a, and 6a-derived chimeras (1 to 3 nM) were approximately 100-fold lower than those for genotypes 2a, 3a, and 5a (range, 80 to 720 nM), implying major differences in response to therapy. In vitro passage in increasing concentrations of BILN 2061 rapidly induced resistance-associated mutations at position 168 in chimeras of all 6 genotypes and at position 156 in genotypes 1b and 4a, each with substantial variability in the identity of substituted amino acids. The system will allow future comprehensive phenotypic characterization of naturally occurring and treatment-induced mutations for PIs in trial or entering clinical use.

scholarly journals ISOZYME VARIATION IN PACIFIC ISLAND CULTIVARS OF BREADFRUIT

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1153g-1154 ◽  
Author(s):  
Diane Ragone
Keyword(s):  
Interspecific Hybrids ◽  
Pacific Islands ◽  
Enzyme System ◽  
Isozyme Variation ◽  
Pacific Island ◽  
Banding Patterns ◽  
Artocarpus Altilis ◽  
Enzyme Systems ◽  
Naturally Occurring ◽  
The Pacific

150 accessions of breadfruit [Artocarpus altilis (Parkinson) Fosberg and A. mariannensis Trècul] and interspecific hybrids from 18 Pacific island groups were analyzed for isozyme variation. Six enzyme systems (ACO, ADH, IDH, MDH, ME, PGM) produced well-resolved bands Each accession was scored for presence or absence of bands for each enzyme system. Breadfruit is clonally propagated and numerous diploid and triploid cultivars are grown in the Pacific islands. Diploid cultivars of A. altilis from Melanesia and western Polynesia showed the highest variation. Few diploid cultivars were found in eastern Polynesia. Seedless, triploid cultivars showed identical banding patterns for all enzyme systems. The narrow genetic variation in triploid cultivars indicates that they are the result of repeated vegetative propagation of a naturally occurring triploid. In contrast, these cultivars exhibit great morphological variation due to somatic mutation, maintained through human selection. A. mariannensis and hybrid cultivars showed greater variation and were identifiable by unique banding patterns for ADH and MDH.

Comparative shoot regeneration in diploid and amphidiploid Brassica species and their interspecific hybrids

1992 ◽  
Vol 70 (7) ◽  
pp. 1513-1514 ◽  
Author(s):  
S. B. Narasimhulu ◽  
Shyam Prakash ◽  
V. L. Chopra ◽  
V. Arunachalam
Keyword(s):  
Key Words ◽  
Shoot Regeneration ◽  
Interspecific Hybrids ◽  
Brassica Species ◽  
The Other ◽  
Genetic Constitution ◽  
Diploid Pollen ◽  
Regeneration Response

Shoot regeneration response in interspecific hybrids of Brassica species were assessed in relation to the diploid pollen parents and amphidiploid female parents. Superior regeneration responses were observed in interspecific combinations of B. carinata and B. nigra (BBC), B. juncea and B. campestris (AAB), and B. napus and B. campestris (AAC). Though synthetic B. napus regenerated with a frequency less than that of the better regenerating parent (B. oleracea), higher regeneration response was observed in the hybrid between B. napus and B. campestris. Two triploid combinations of the genetic constitution ABC, one obtained by crossing synthetic B. napus with B. nigra and the other by crossing natural B. juncea with B. oleracea, showed low regeneration responses. The response improved substantially in a tetraploid of the constitution ABBC obtained by crossing B. juncea with B. carinata. Key words: Brassica, alloploids, shoot regeneration.

CONTRIBUTION A L'ETUDE CYTOTAXONOMIQUE D'ESPECES MEDITERRANEENNES D'ANEMONE ET DE LEURS HYBRIDES

1976 ◽  
Vol 18 (1) ◽  
pp. 151-168 ◽  
Author(s):  
Nicole Maïa ◽  
P. Venard
Keyword(s):  
Interspecific Hybrids ◽  
Meiotic Abnormalities ◽  
Meiotic Behavior ◽  
Statistical Comparison ◽  
Chromosomal Pair ◽  
Chromosome Alteration ◽  
Cultivated Species ◽  
Alien Cytoplasm ◽  
Tetraploid Level ◽  
Good Agreement

Statistical comparison of the caryotypes of the four Mediterranean Anemone species: A. palmata L., A. coronaria L., A. pavonina Lamk. and A. hortensis L., is based on the dispersion areas of the T/Θ and L/C parameters estimated for each chromosomal pair. Chromosome alteration has been observed in both interspecific hybrids obtained. These alterations are more marked when the genome is transferred into an alien cytoplasm. The F1 hybrid A. pavonina × A. hortensis is fertile with some meiotic abnormalities. Sterility of the A. pavonina × A. coronaria F1 hybrid is caused by the failure of pairing. Chromosomal doubling by colchicine restored fertility. Phylogenic relations as established by morphological, biochemical and caryotypic characters, as well as by meiotic behavior of interspecific hybrids, are in good agreement. The lack of introgression of new characters into the cultivated species A. coronaria is due to interspecific sterility barriers. Nevertheless, the introduction of the coronaria genome into the cytoplasm of pavonina would be a source of male-sterility at the tetraploid level.

scholarly journals A plasmid-cured Chlamydia muridarum strain displays altered plaque morphology and reduced infectivity in cell culture

Microbiology ◽  
2006 ◽  
Vol 152 (6) ◽  
pp. 1601-1607 ◽  
Author(s):  
Catherine M. O'Connell ◽  
Kristy M. Nicks
Keyword(s):  
Phenotypic Characterization ◽  
Plaque Morphology ◽  
Wild Type ◽  
Chlamydia Muridarum ◽  
Isolation And Characterization ◽  
Naturally Occurring ◽  
Intracytoplasmic Inclusions ◽  
Derivatives Of ◽  
Wild Type Parent

A highly conserved cryptic plasmid is present in Chlamydia trachomatis yet naturally occurring plasmid-deficient isolates are very rare. This paper describes the isolation and characterization of a plasmid-deficient strain of C. muridarum, using novobiocin as a curing agent. Plasmid-deficient derivatives of C. muridarum strain Nigg were generated at high efficiencies (4–30 %). Phenotypic characterization revealed that the cured derivative was unable to accumulate glycogen within intracytoplasmic inclusions. In addition, this strain formed small plaques at a reduced efficiency compared to the wild-type parent.

Natural hybridization between Murray cod, Maccullochella peelii peelii (Mitchell) and trout cod, Maccullochella macquariensis (Cuvier) (Percichthyidae) in the Murray River, Australia

1995 ◽  
Vol 46 (4) ◽  
pp. 729 ◽  
Author(s):  
JW Douglas ◽  
GJ Gooley ◽  
BA Ingram ◽  
ND Murray ◽  
LD Brown
Keyword(s):  
Interspecific Hybrids ◽  
First Generation ◽  
First Record ◽  
Natural Hybridization ◽  
Wild Populations ◽  
Sympatric Populations ◽  
Naturally Occurring ◽  
Murray River ◽  
Management Policies ◽  
Murray Cod

Hybridization is confirmed between two wild, naturally sympatric populations of Murray cod, Maccullochella peelii peelii, and trout cod, M. macquariensis, from the Murray River, Australia. Electrophoretic comparisons of proteins in muscle and liver tissues from trout cod, Murray cod, an artificially produced hybrid of Murray cod and trout cod, and putative wild hybrids from the Murray River indicated that the last group were first-generation interspecific hybrids. This is the first record of hybridization between naturally occumng populations of these two species. Naturally occurring wild populations of both trout cod and Murray cod are nonetheless genetically distinct and there is no evidence of introgression between the species. These findings have some implications for management policies and practices in relation to both species, and these are discussed.

scholarly journals PATHWAYS OF BACKCROSSING ZINNIA ANGUSTIFOLIA × Z. ELEGANS INTERSPECIFIC HYBRIDS TO THE PARENTAL SPECIES

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1070a-1070
Author(s):  
Thomas H. Boyle
Keyword(s):  
Powdery Mildew ◽  
Pollen Tube ◽  
Pollen Germination ◽  
Interspecific Hybrids ◽  
Xanthomonas Campestris ◽  
Parental Species ◽  
Developmental Abnormalities ◽  
Erysiphe Cichoracearum ◽  
Zinnia Angustifolia ◽  
Pollen Tube Penetration

Allotetraploid Z. angustifolia × Z. elegans hybrids (2 n =46) were reciprocally backcrossed to Z. angustifolia (2 n = 22 or 44) and Z. elegans (2 n = 24 or 48). Pollen germination and pollen tube penetration of the stigmatic surface were observed for all 8 cross combinations. At 14 days after pollination, the percentage of florets with embryos ranged from 0 to 69%, and some hybrid embryos exhibited developmental abnormalities. Seed-propagated backcross (BC1) populations were generated with Z. angustifolia (2 n =44)as ♀ or ♂, and Z. elegans (2 n =48) as ♀ BC1 progeny from these 3 crosses demonstrated low to high levels of resistance to bacterial leaf and flower spot (incited by Xanthomonas campestris pv. zinniae) and high levels of resistance to powdery mildew (incited by Erysiphe cichoracearum). BC1 hybrids derived from crossing allotetraploid hybrids as ♀ and Z. elegans (2 n =48) lines have commercial potential as disease-resistant, flowering annuals.

Sign in / Sign up

Export Citation Format

Share Document