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1.
M. C. Vaz Patto P. M. Moreira V. Carvalho S. Pego 《Genetic Resources and Crop Evolution》2007,54(7):1555-1563
The Portuguese maize bread (“broa”) manufactured from traditional maize landraces still plays an important economic and social
role on Central and Northern rural communities of the country. However the traditional maize landraces agricultural systems
are changing. Local maize landraces are in risk of disappearing because of the progressive adoption of hybrid varieties not
suitable for bread production. These changes are contributing to a major loss of genetic diversity. An expedition took place
in the Central region of Portugal (Beira Interior and Beira Litoral) with the purpose of collecting enduring maize landraces
with technological ability for bread production and to access the possibility of establishing a participatory plant breeding
and conservation program. A total of 51 different maize landraces and 175 other varieties of associated crops were collected.
Maize landraces showed to maintain high diversity and potential for improvement. The production relayed on small farms with
polycrop, quality oriented, sustainable systems. A participatory plant breeding and conservation program would be possible
on this region with the proviso that local authorities would be involved. This program would allow a higher valuation of these
maize populations, contributing to halt the current loss of these unique Portuguese maize landraces. 相似文献
2.
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
3.
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
4.
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.
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
7.
8.
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
9.
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
10.
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.
T. A. Pshenichnikova I. F. Lapochkina L. V. Shchukina 《Genetic Resources and Crop Evolution》2007,54(2):287-293
The genetic control of morphological characters and gliadin composition was studied in two bread wheat lines with introgressed
segments from Aegilops speltoides Tausch. It was found that the transferred trait of leaf hairiness is controlled by one dominant gene, non-allelic to the
known gene, Hl1. It was localized in 7B chromosome. Whole plant non-glaucousness is under the control of an inhibitor gene, allelic to the
gene W1I of wheat located on chromosome 2B. This gene was found to be epistatic to the gene controlling spike waxlessness. The introgressed
gene for spike glume color was found to be allelic to the Rg1 gene located on 1BS of common wheat, but it was linked with another allele of the gliadin locus Gli-B1. 相似文献
14.
Fernando González-Andrés Pedro A. Casquero Cristina San-Pedro Elías Hernández-Sánchez 《Genetic Resources and Crop Evolution》2007,54(1):27-44
All the accessions (35) of white lupin (Lupinus albus L.) landraces collected from northwest Iberian plateau and maintained at the Spanish germplasm collection (CRF of INIA),
were studied with the general objective of assessing the biodiversity of these landraces and to ascertain their value as genetic
resources for the development of germplasm adapted to the areas where they were collected with long and chilly winters. The
characterization study comprised 51 qualitative and 50 quantitative characters. Quantitative parameters were analyzed by Principal
Components Analysis (PCA). The 2-dimensional plot (49.3% of cumulative variability) formed a main group of accessions and
4 outliers (#1, #9, #27 and #28) separated in the first PC. The characters with a higher contribution to the first PC were
inflorescence length, leaf petiole length and leaf central foliole area. The presence of alkaloids, the percentage of plants
killed by soil borne fungal diseases, the phenology, the yield per plant and yield components were also assessed. Twenty six
accessions (the main group in the PCA plot) showed high homogeneity, with the following highlights: bitterness, indeterminate
growth habit, early ripeness and spring sowing with the exception of #18, in which seeding date is unknown and it had a later
phenology. By contrast accessions #9 and #27 were bitter of autumn sowing with determinate growing habit and they had the
longest values of primary inflorescence length and a later phenology when they were sown in spring. Average values for yield
and yield components showed a broad range of variation between accessions. The main yield component was the number of pods
per plant. Accession #22 had the highest mean seed mass, although this had not significant influence in yield. Accession #17
showed the highest yield and #1 the lowest. This last also had the lowest values of inflorescence length, leaf petiole length
and leaf central foliole area. No significant differences of resistance to soil-borne fungi were found between accessions.
The year had a significant effect in the phenology, yield and yield components except for number of seeds per pod. The studied
material might be of interest for the development of spring sowing germplasm adapted to north Iberian peninsula. 相似文献
15.
Pedro Revilla Pablo Velasco Rosa Ana Malvar María Elena Cartea Amando Ordás 《Genetic Resources and Crop Evolution》2006,53(4):771-777
Genotypes conserved in active collections may suffer genetic erosion and modifications. The objective of this work was to
investigate changes in germination and vigour in maize (Zea mays L.) inbred lines during cold storage in an active collection. Seeds of 16 maize inbreds produced along 16 years were evaluated
for emergence and seedling vigour in a growth chamber. Linear and quadratic regressions of vigour and viability-related traits
over seed age were calculated and tested for homogeneity. The seed of five production years of five inbreds that behaved differently
in the regression analysis was multiplied in 1998, and original and renewed seed were evaluated in a growth chamber in 1999.
Viability and vigour decreased linearly with age for most inbreds, particularly for B84 and EP10, varied at random for a few
inbreds, and remained high for EP56 and A295. Aging caused reduction of vigour and loss of viability in most inbreds. There
was variability for seed longevity among inbred lines; longevity was highest for inbred EP56. During storage, some seeds of
each inbred died, while enduring seeds, when multiplied, produced new seed with enhanced viability and vigour compared to
the average seed of the inbred, suggesting natural selection for viability and vigour during storage within inbred lines. 相似文献
16.
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
17.
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
18.
L. S. Rao P. Usha Rani P. S. Deshmukh P. A. Kumar S. K. Panguluri 《Genetic Resources and Crop Evolution》2007,54(6):1235-1244
Detection of genetic relationships between 19 chickpea cultivars and five accessions of its wild progenitor Cicer reticulatum Ladizinsky were investigated by using RAPD and ISSR markers. On an average, six bands per primer were observed in RAPD analysis
and 11 bands per primer in ISSR analysis. In RAPD, the wild accessions shared 77.8% polymorphic bands with chickpea cultivars,
whereas they shared 79.6% polymorphic bands in ISSR analysis. In RAPD analysis 51.7% and 50.5% polymorphic bands were observed
among wild accessions and chickpea cultivars, respectively. Similarly, 65.63% and 56.25% polymorphic bands were found in ISSR
analysis. The dendrogram developed by pooling the data of RAPD and ISSR analysis revealed that the wild accessions and the
ICCV lines showed similar pattern with the dendrogram of RAPD analysis. The ISSR analysis clearly indicated that even with
six polymorphic primers, reliable estimation of genetic diversity could be obtained, while nearly 30 primers are required
for RAPD. Moreover, RAPD can cause genotyping errors due to competition in the amplification of all RAPD fragments. The markers
generated by ISSR and RAPD assays can provide practical information for the management of genetic resources. For the selection
of good parental material in breeding programs the genetic data produced through ISSR can be used to correlate with the relationship
measures based on pedigree data and morphological traits to minimize the individual inaccuracies in chickpea. 相似文献
19.
Cherimoya (Anonna cherimola Mill.) is a fruit tree which originated in Peru and Ecuador and is now cultivated in several subtropical areas of the world. The characterization of cherimoya cultivars at allozyme level has been previously reported, but the geographic distribution and organization of this variation have not been fully characterized. In this study, we assessed the relationships among 206 cherimoya and four atemoya (A. cherimola ×A. squamosa) cultivars based on allozyme polymorphism. We have confirmed the genetic differences between atemoya and cherimoya cultivars, and showed that cherimoya accessions from Madeira, Bolivia and Spain form homogeneous groups of cultivars. Accessions from Chile and California form heterogeneous groups, probably due to their mixed origins. Cultivars from Peru and Ecuador showed a wide range of allelic variation, as is expected for accessions from the center of origin of this species. 相似文献
20.
Amer Ibrahim Basha Stefano Padulosi Kamel Chabane Adnan Hadj-Hassan Ehsan Dulloo Mario Augusto Pagnotta Enrico Porceddu 《Genetic Resources and Crop Evolution》2007,54(8):1807-1816
Pistachio (Pistacia vera L.) is a strategic nut tree species in the Middle East which holds comparative advantage over other fruit trees in view of
its hardiness, income generation opportunities and benefits for the ecosystem. Yet pistachio cultivation depends on a very
narrow genetic base, in spite of the existence of many varieties still marginally exploited. Syria is an important center
of diversity for pistachio. A country wide ecogeographic survey in this country was carried out to determine the extent of
pistachio genetic diversity and its use. As a whole, 114 accessions were collected from 37 farms to assess diversity at morphological
and molecular level. Molecular evaluation was carried out using Amplified Fragment Length Polymorphism (AFLP) technique and
performed using seven primer pair combinations. Results from the studies allowed the identification of 25 pistachio female
varieties in Syria, some of which unique and described for the first time. Three groups of pistachio diversity were identified
by cluster analysis which provides useful information about the distribution of genetic diversity in Syria for enhanced use
and sustainable conservation. 相似文献