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1.
R. Alonso Ferro I. Brichette G. Evgenidis Ch. Karamaligkas J. Moreno-González 《Genetic Resources and Crop Evolution》2007,54(2):295-308
An European maize (Zea mays L.) landrace core collection (EMLCC) was formed with samples from several countries. Evaluation of the EMLCC may contribute
to broad the genetic base of maize breeding programs. The objective of this study was to assess the variability of EMLCC under
low nitrogen (N) in relation to high N input. Eighty-five landraces of the EMLCC, grouped in four maturity groups, and three
check hybrids were evaluated for response to low (0 kg ha−1) and high (150 kg ha−1) N in Spain and Greece. Five plant size traits (plant height, ear height, leaf length, leaf width and leaf area index), two
grain traits (1000-kernel weight and grain yield), and two agronomic traits [growing degree units (GDU) and lodging] were
studied. Overall means of plant size and grain traits increased when genotypes were grown at 150-N relative to 0-N input.
The relative increase for grain traits was smaller in landraces than in hybrids. This suggests that landraces had lower grain
yield response to N supply compared to hybrids. Linear regressions of plant size traits on GDU indicated that vegetative development
was primarily associated with flowering lateness. The maturity group was the main source of variation for all traits. Landrace
variability within maturity groups was significant for all traits across environments, despite significant landrace × environment
interactions. Estimates of genetic and genotype × environment variances, and heritabilities at both high and low N inputs
were not significantly different from each other. However estimates were generally larger at high N. Genetic and phenotypic
correlation coefficients between the two N levels were very high for all traits. 相似文献
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Tobias W. Eschholz Roland Peter Peter Stamp Andreas Hund 《Genetic Resources and Crop Evolution》2008,55(7):971-983
About 65 years ago, more than 150 Swiss maize landraces (Zea mays L. ssp. mays) of the flint type were collected and conserved ex situ. Due to the climatically and culturally diverse environment of the Alps, a considerable genetic diversity of this material
was assumed. To prove this, an efficient method was required to carry out genetic profiling of all the accessions in the Swiss
Gene Bank. Simple sequence repeat marker (SSR) profiling in combination with the visualization of the polymerase chain reaction
(PCR) products on agarose gels was chosen. Here a set of 19 different landrace accessions was analyzed to: (i) investigate
their genetic diversity, (ii) investigate and display the population structure and (iii) determine whether DNA bulks rather
than single plants can be used for such analyses. Four repeated samples of one accession were found to be much closer to one
another than to the rest of accessions. Furthermore, specific alleles were identified for several accessions. The PCR products
of the bulked DNA samples represented only a small part of the variation revealed by the analysis of individuals. Loci with
four base repeat motifs performed better in the analysis of bulks than loci with other repeat motifs. The correlation between
genetic distance matrices, based on the analysis of individuals and bulks, respectively, was significant. Thus, the single
plant approach allowed for sufficient differentiation of accessions, and DNA bulks visualized on agarose gels led to correlated
genetic distances although a limited number of alleles were detected. Although the limited resolution of agarose gels likely
causes some bias, profiling of larger sets with the individual plant approach appears feasible and more informative compared
to the bulk analysis we conducted. 相似文献
4.
Marc Moragues Marian Moralejo Mark E. Sorrells Conxita Royo 《Genetic Resources and Crop Evolution》2007,54(5):1133-1144
A comprehensive characterization of crop germplasm is critical to the optimal improvement of the quality and productivity
of crops. Genetic relationships and variability were evaluated among 63 durum wheat landraces from the Mediterranean basin
using amplified fragment length polymorphisms (AFLPs) and microsatellites markers. The genetic diversity indices found were
comparable to those of other crop species, with average polymorphism information content (PIC) values of 0.24 and 0.70 for
AFLP and microsatellites, respectively. The mean number of alleles observed for the microsatellites loci was 9.15. Non-metric
multi-dimensional scaling clustered the accessions according to their geographical origin with the landraces from the South
shore of the Mediterranean Sea closely related. The results support two dispersal patterns of durum wheat in the Mediterranean
basin, one through its north side and a second one through its south side. 相似文献
5.
This study aimed to investigate the effect of inoculation with plant growth-promoting Rhizobium and Pseudomonas species on NaCl-affected maize. Two cultivars of maize (cv. Agaiti 2002 and cv. Av 4001) selected on the basis of their yield
potential were grown in pots outdoors under natural conditions during July. Microorganisms were applied at seedling stage
and salt stress was induced 21 days after sowing and maintained up to 50% flowering after 120 days of stress. The salt treatment
caused a detrimental effect on growth and development of plants. Co-inoculation resulted in some positive adaptative responses
of maize plants under salinity. The salt tolerance from inoculation was generally mediated by decreases in electrolyte leakage
and in osmotic potential, an increase in osmoregulant (proline) production, maintenance of relative water content of leaves,
and selective uptake of K ions. Generally, the microbial strain acted synergistically. However, under unstressed conditions,
Rhizobium was more effective than Pseudomonas but under salt stress the favorable effect was observed even if some exceptions were also observed. The maize cv. Agaiti
2002 appeared to be more responsive to inoculation and was relatively less tolerant to salt compared to that of cv. Av 4001. 相似文献
6.
I. Zein G. Wenzel J. R. Andersen T. Lübberstedt 《Genetic Resources and Crop Evolution》2007,54(1):139-148
During recent decades, the whole plant yield of European maize (Zea mays L.) has increased substantially. However, during the same period of time cell wall digestibility, and consequently fodder
quality, has decreased. Alleles for digestible cell walls have thus been lost, either during breeding for stalk standability
or by genetic drift during breeding for grain yield. The brown-midrib 3 mutant (bm3) in maize (Z. mays L.), controlled by the caffeic acid O-methyl transferase (COMT) locus, has a positive influence on maize fodder quality.
In this study, 42 European maize lines were used to evaluate the nucleotide diversity and linkage disequilibrium (LD) pattern
across 2.3 kb of this locus. In agreement with what has been found for other maize loci, we found high diversity values (π = 0.00834),
rapid LD decay even in an elite line sample, and indication of selection as well as of recombination events for seven site
combinations. The diversity values differed slightly between inbreds of the Flint and Dent pools and most haplotypes were
specific for one of the two heterotic groups. The polymorphisms identified at this single locus enable the construction of
single nucleotide polymorphisms (SNP) and indel markers for haplotype identification and a rough discrimination of inbreds
into Flint and Dent heterotic groups. The results reported here document the degree of allelic diversity in breeding materials
and allow for targeted search of novel alleles in genetic resources. 相似文献
7.
The pink stem borer (Sesamia nonagrioides Lef.) is the main corn (Zea mays L.) pest in the Mediterranean area. Although, screening for resistance to this pest has been successful, the level of resistance
shown by the most resistant varieties is not high. The objectives of the present work were: (i) the evaluation for pink stem
borer resistance of the nontested inbred lines, field and popcorn materials, from the collection maintained at the Misión
Biológica de Galicia and (ii) the study of the performance, under pink stem borer infestation, of inbreds selected for resistance
to pink stem borer in hybrid combination. Forty four inbred lines nontested yet for resistant to pink stem borer along with
five inbred lines previously reported as resistant to stem and ear attack, were evaluated in 2002 and 2003. In adjacent experiments,
hybrids EP79× W552, EP77× B93, and A661× EP42 were tested along with a resistant hybrid, MEB531-Bt, and a susceptible hybrid, INRA 260. New sources of resistance to pink stem borer have been detected among inbred lines improving
the level of resistance presented by previously tested inbreds. Some of these lines were successfully developed by pedigree
selection for resistance to pink stem borer. 相似文献
8.
Jorge Cunha Margarida Baleiras-Couto José P. Cunha Jorgete Banza Adelaide Soveral Luís C. Carneiro José E. Eiras-Dias 《Genetic Resources and Crop Evolution》2007,54(5):981-988
Wild populations of Vitis vinifera L.␣have been located in Portugal. Morphological characterization was carried out in three populations located in Alcácer
do Sal, Castelo Branco, and Montemor-o-Novo, and then compared using multivariate discriminant analysis. These populations
were from three different hydrological basins, therefore cross-pollination was not possible. It was verified that in each
population all plants were different. The data suggest that the frequency of female and male plants is rather variable in
wild populations. The morphology of the adult leaf, from the Alcácer do Sal population, had particular features when compared
with Castelo Branco and Montemor-o-Novo populations, which were more homogeneous. The length of teeth compared with width
at the end of the base, and the density of prostrate hairs between and on main veins (lower side) were the variables which
allowed the best discrimination among populations. 相似文献
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11.
Francisco Perdomo-Roldán Manuel A. Galindo-Reyes Heike Vibrans 《Genetic Resources and Crop Evolution》2009,56(3):353-362
This study explores the morphological variability and resource allocation of weedy, annual teosinte (Zea mays ssp. mexicana (Schrader) Iltis, Chalco race) from the Valley of Toluca, central Mexico, and compares it with data reported for maize. One
hundred mature and fertile teosinte plants were selected for variation in size and measured. The extremes found for fertile
plants were 0.12 and 3.5 m in height and 0.09 vs. 694 g in weight. Fruit were polymorphic, with significant correlation between
color and weight. Small plants invested slightly more biomass in the leaves and tall plants invested more in the stem. The
minimum mass necessary to produce fertile plants was much lower in teosinte than in maize. Very small teosinte plants formed
only female inflorescences, whereas maize produces a tassel. The harvest index was similar to landrace maize, and did not
decrease in taller plants, as teosinte can increase the reproductive sink. Toluca teosinte retains several important characteristics
of weeds: size variability, adaptation of fruit quantity to environmental conditions, and fruit polymorphism. 相似文献
12.
Elizabeth Rice 《Genetic Resources and Crop Evolution》2007,54(4):701-713
Using survey data from Jala, Mexico, this case-study evaluates in situ maize conservation of the variety ‘Jala’ (Zea mays L.). Though historically ‘Jala’ was the dominant variety grown in the valley of Jala, today less than 20% of farmers grow
it on only 5% of the maize area. Younger growers of the ‘Jala’ variety specialize in it, growing relatively large amounts
for niche markets. Older, diversified farmers grow small areas for household use and to compete in a local contest. Conservation
of the ‘Jala’ variety has been heavily influenced by shifting ideal concepts of maize, as determined by market and consumption
demands and by a contest designed to promote in situ conservation. The current move away from nationalized purchasing may
favor ‘Jala’s’ continued conservation. 相似文献
13.
In this study, the effects of growing maize plants on the microbial decomposition of easily degradable plant residues were
investigated in a 90-day pot experiment using a sandy arable soil. Four treatments were carried out: (1) untreated control,
(2) with freshly chopped alfalfa residues (Medicago sativa L.) incorporated into soil, (3) with growing maize plants (Zea mays L.), and (4) with growing maize plants and freshly chopped alfalfa residues incorporated into soil. The amount of alfalfa
residues was equivalent to 1.5 mg C g−1 soil and 120 μg N g−1 soil. At the end of the experiment, only the combination of growing maize plants and alfalfa residues significantly increased
the contents of microbial biomass C, microbial biomass N, and ergosterol in soil compared to the non-amended control. The
dry weight of the maize shoot material was more than doubled in the treatment with alfalfa residues than without. In treatment
(2), 6% of the alfalfa residues could be recovered as plant remains >2 mm. In treatment (4), this fraction contained 14.7%
alfalfa residues and 85.3% maize root remains, calculated on the basis of δ
13C values. This means that 60% more alfalfa-C was recovered than in treatment (2). The reasons for the retardation in the breakdown
of alfalfa residues might be water deficiency of soil microorganisms in the increased presence of maize roots. Assuming that
the addition of alfalfa residues did not affect the decomposition of native soil organic matter, only 23% of the alfalfa residues
were found as CO2 monitored with a portable gas analyzer with a dynamic chamber. The discrepancy is probably due to problems in measuring peak
concentrations of CO2 evolution in the two alfalfa treatments at the beginning of the experiment and in the two maize treatments at the end, especially
in treatment (4). 相似文献
14.
S. D. Segura G. Coppens d’Eeckenbrugge C. H. Ocampo P. Ollitrault 《Genetic Resources and Crop Evolution》2005,52(4):455-463
In a general study of banana passion fruit genetic resources, diversity was analyzed in the two main cultigens, P. tripartita
var. mollissima and P. tarminiana, and their closest wild relative, P. mixta, scoring isozyme bands (IDH,PGM,ACP,PGD,DIA,andPRX)
on288 plants from 31 accessions. Polymorphismandallelic richness, Nei diversity indices, and neighbor joining clustering showed
that variation was poor in the cultigens in northern and central Colombia, while P. mixta appeared much more polymorphic.
The populations of P. tripartita var. mollissima and P. mixta from southern Colombia and Ecuador show higher diversity values
and are clearly differentiated from those of central and northern Colombia. This geographic component of variation is even
stronger than the interspecific one, which suggests a close relation and a regular gene flow between these two species. In
contrast, all the accessions of P. tarminiana constitute a clearly differentiated group, even if some introgression with P.
tripartita var. mollissima is also suspected. The high variation observed in the southern region indicates the proximity of
a center of diversity for banana passion fruit and collecting in Ecuador, Peru and Bolivia is recommended. The high diversity
of P. mixta and the evidence of gene flow with P. tripartita var. mollissima constitute a favorable context for the implementation
of in situ conservation strategies. 相似文献
15.
Bettina Heider Elke Fischer Tanja Berndl Rainer Schultze-Kraft 《Genetic Resources and Crop Evolution》2007,54(3):529-542
Pueraria montana var. lobata and P. phaseoloides originating from tropical Asia and parts of Oceania are ecologically and economically important legumes that are used as
green manure, cover crop or forage plants. Conservation and use of plant genetic resources require an understanding of the
extent and distribution of genetic diversity in any given region. In this study, genetic variation of five P. montana var. lobata and 16 P. phaseoloides accessions was analysed developing a random amplified polymorphic DNA (RAPD) marker methodology for Pueraria species and thereby creating basic data for follow-up research and the development of conservation strategies. Seeds were
collected from native populations in Bac Kan Province, a mountainous region in Northeast Vietnam. P. montana var. lobata presented a high level of variation with 54.3% of the detected markers being polymorphic, whereas P. phaseoloides exhibited an intermediate to high level of variation (45.5%). The P. montana var. lobata accessions clustered in congruence with their eco-geographical origin. For P. phaseoloides no correspondence between sampling sites and genetic differentiation was found. Inter-population differentiation was measured
as Jaccard's similarity coefficient (JSC). Mean JSC amounted to 0.35 in P. montana var. lobata and 0.52 in P. phaseoloides. Results are compared to other genetic studies of herbaceous legumes and conservation strategies are suggested. 相似文献
16.
Adriana Montañez Cecilia Abreu Paul R. Gill Gudni Hardarson Margarita Sicardi 《Biology and Fertility of Soils》2009,45(3):253-263
The nitrogen-fixing capacity of a range of commercial cultivars of maize (Zea mays L.) was evaluated by the 15N isotope-dilution method. Biological nitrogen fixation (BNF) expressed as percent nitrogen derived from air (Ndfa) ranged
from 12 to 33 regardless of nitrogen fertilization. BNF was not affected by mineral nitrogen fertilization except on cultivar
Topacio and PAU-871 cultivars. Subsequently, culturable bacterial diazotrophs were isolated from endophytic tissue of maize:
seed, root, stem, and leaf. All isolates were able to grow on N-free semisolid medium. Eleven bacteria isolates showed nitrogen-fixing
capacity by the reduction of acetylene to ethylene and confirmed by PCR the presence of nifH gene in their genome. Identification of the 11 isolates was performed by bacteriological methods, 16S rRNA gene sequences,
and phylogenetic analysis, which indicated that the bacteria isolated were closely related to Pantoea, Pseudomonas, Rhanella, Herbaspirillum, Azospirillum, Rhizobium (Agrobacterium), and Brevundimonas. This study demonstrated that maize cultivars obtain significant nitrogen from BNF, varying by maize cultivar and nitrogen
fertilization level. The endophytic diazotrophic bacteria isolated from root, stem, and leaf tissues of maize cultivars may
contribute to BNF in these plants. 相似文献
17.
N. P. S. Dhillon R. Ranjana Kuldeep Singh I. Eduardo A. J. Monforte M. Pitrat N. K. Dhillon P. P. Singh 《Genetic Resources and Crop Evolution》2007,54(6):1267-1283
Diversity among 36 snapmelon landraces, collected from 2 agro-ecological regions of India (9 agro-climatic sub-regions), was
assayed using RAPD primers, morphological traits of plant habit and fruit, 2 yield-associated traits, pest and disease resistance
and biochemical composition (TSS, ascorbic acid, titrable acidity). Typical differences among accessions were observed in
plant and fruit characteristics and snapmelon germplasm with high titrable acidity and possessing resistance to downy mildew,
Cucumber mosaic virus, Zucchini yellow mosaic virus, Papaya ringspot virus, Aphis gossypii and Meloidogyne incognita was noticed in the collection. RAPD based grouping analysis revealed that Indian snapmelon was rich in genetic variation
and region and sub-region approach should be followed across India for acquisition of additional melon landraces. Accessions
of var. agrestis and var. momordica clustered together and there was a separate cluster of the accessions of var. reticulatus. Comparative analysis of the genetic variability among Indian snapmelons and an array of previously characterized reference
accessions of melon from Spain, Israel, Korea, Japan, Maldives, Iraq, Pakistan and India using SSRs showed that Indian snapmelon
germplasm contained a high degree of unique genetic variability which was needed to be preserved to broaden the genetic base
of melon germplasm available with the scientific community.
N. P. S. Dhillon and Ranjana contributed equally to this work and are considered the first authors. 相似文献
18.
The study here was conducted on nearly 12,000 apricot seedlings in the Malatya Region in the Eastern part of Turkey. This
region is famous for its horticulture based mainly on apricot production and the Country's highest apricot production originates
from this region. The flower and fruit characteristics of all populations, which include apricot seedlings, in the region
were evaluated. Based on their horticultural performances, 13 genotypes were selected, of which seven were considered as apricots
served in dried form and six as in table consumption form. Among the selected genotypes, the fruit weight ranged between 28.5
and 71.19 g, soluble solids ranged between 12.7 and 26.5%, while the range in total acidity was between 0.35 and 1.80% and
fruit development period was between 87 and 183 days. To determine the selected genotypes performance in a similar environment,
they were grafted on to 4-year-old rootstocks. The results from these combinations showed that there was some decrease, especially
in fruit size and soluble solids, in the genotypes performance when compared to the results of the initial observations. Some
differences were also detected in taste, fruit shape, pit shape, fruit flesh firmness, skin and flesh colors. The dry fruit
yield was determined as 22.50–28.36% for the selected dry apricot genotypes. The dry fruit yield of all seven genotypes considered
for dry consumption were similar to ‘Hacıhaliloğlu’ and higher than ‘Canino’, which were evaluated as control cultivars. 相似文献
19.
Gert Poulsen Claus Holten Roland von Bothmer 《Genetic Resources and Crop Evolution》2007,54(5):1105-1115
Dead seeds of a fodder beet cultivar ‘Elvetham’ stored under ambient conditions since 1880 were compared to a homonymous sample
preserved in an on-farm situation in Denmark. DNA was isolated from single seeds and successfully applied to Amplified Fragment
Length Polymorphism (AFLP) analysis of the accessions. Six primer pairs were used to determine the similarity between the
two accessions based on 112 polymorphic bands. Furthermore, similarity among seven cultivars of fodder beets representing
the main types used in Scandinavia at the end of the 19th century was determined. This analysis was based on 152 polymorphic
bands. Differentiation among the seven cultivars was determined to a mean G
ST value of 0.438, while G
ST between the two ‘Elvetham’ accessions was 0.266. A principal coordinate analysis based on jaccards similarity index illustrates
that the two ‘Elvetham’ accessions are different from each other. The differentiation is higher than the value found between
two separate ‘Eckerndorfer’ accessions. The results indicate that the cultivated accession has changed. Additionally, the
value of applying old dead seed material for documentation in gene banks is demonstrated.
During the analysis it was found that DNA isolated from seeds and leaves behaved differently in the AFLP process, however,
the two fractions assigned to their common accession. 相似文献
20.
The genus Nicotiana is a member of the nightshade (Solanaceae) family, and is comprised of 70 currently recognized, naturally occurring species.
Genetic variability within N. tabacum L., the species of primary economic importance, was likely affected by several genetic bottlenecks. Nicotiana tabacum is a classic amphidiploid that arose after chance interspecific hybridization between N. sylvestris Spegazinni et Comes and a member of section Tomentosae, likely N. tomentosiformis Goodspeed, N. otophora Grisebach, or an introgressive hybrid between the two. Only a fraction of the genetic variability that existed in the diploid
progenitor gene pools probably entered into N. tabacum. Genetic drift, coupled with natural and human selection, subsequently resulted in the formation of narrow genetic pools
corresponding to modern commercial market classes. Genetic variability in Nicotiana has gained increased attention in recent years because of investment in Nicotiana genomics research, interest in development of tobacco products with reduced harm characteristics, and concentration on using
Nicotiana species for plant-based production of commercially useful proteins. A storehouse of genetic diversity for N. tabacum is available in approximately 1,900 accessions maintained by the United States Nicotiana Germplasm Collection. Seeds of 224 accessions representing 59 wild Nicotiana species are also maintained. The collection is currently maintained by North Carolina State University and is part of the
United States National Plant Germplasm System (NPGS). The collection’s curator satisfies hundreds of seed requests made annually
by scientists using Nicotiana germplasm for basic biological investigations and by researchers in the area of applied tobacco science. 相似文献