Search Results

You are looking at 1 - 10 of 147 items for :

  • "landraces" x
  • Biology and Life Sciences x
  • Refine by Access: All Content x
Clear All

Due to their good early vigour, Swiss maize landraces have been used extensively to develop the Flint Pool of European hybrid-breeding programmes. However, the basis of good early vigour, especially under cool conditions, has not been elucidated. Of 166 pre-screened Swiss maize landraces, 17 contrasting accessions were tested together with two control accessions, a German landrace and a modern hybrid cultivar with proven good early vigour, at sites in the midlands and the foothills of the Alps in Switzerland. To investigate early vigour, photosynthesis, leaf greenness and plant growth were recorded. Compared to the modern standard hybrid cultivar, northern accessions showed superior early vigour under cold stress in the field for all traits examined in these experiments, whereas these traits were much less pronounced in southern accessions. In particular, some accessions from the Rhine valley seem to be promising sources of early vigour for use in breeding programmes. These findings support the hypothesis that long-term selection resulted in the adaptation of maize landraces to their local environment. Compared to the phylogenetic tree, it is evident that accessions with superior early vigour are related to each other and originated in the Rhine valley.

Restricted access

Durum wheat landraces are still cultivated to take advantage of their excellent grain and straw quality, adaptation to abiotic stresses, and extremely wide variety of uses. The safeguarding and rehabilitation of genetic inheritance requires genetic characterization and evaluation. In this study, forty durum wheat landraces originating from Mediterranean countries were evaluated according to agro-morphological and technological properties. We show that the germplasm was highly variable. The mean yellow pigment and protein content was higher in landraces (15.58%; 7.32 ppm) than in the Moroccan cultivars used as controls (14.6%; 5.48 ppm). In addition, principal component analysis identified five groups showing variable agronomic and qualitative characteristics that might be useful in the rational design of breeding programs.

Restricted access

Genetic variation in the flint maize (Zea mays L. conv. indurata) gene pool has decreased significantly since the introduction of hybrid breeding into Europe in the 1950s, leading to greater genetic vulnerability. Landraces, stored in gene banks, offer a valuable source to broaden the genetic basis again. The objective of this study was the genetic characterization of 166 Swiss landrace accessions originating from 7 Swiss regions (alpine valleys). The material was fingerprinted using a set of ten SSRs (Simple Sequence Repeat Markers). The resulting cladogram showed three main clusters comprising 95, 22 and 49 accessions, respectively. The largest group of accessions, from the Rhine valley of St. Gallen (RT), was present in all three main clusters. However, the majority of RT accessions was found in the first main cluster, together with those from the western neighbouring region (Linthtal) and from the southwestern neighbouring region (Wallis). Those from Tessin (southern Switzerland) were found mainly in one sub-cluster within the third main cluster. This is a very encouraging first step in appraising the genetic differences among accessions from Swiss regions.

Restricted access

Nineteen landrace populations of Turkish cultivated emmer wheat [Triticum turgidum L. ssp. dicoccon (Schrank) Thell.] were characterized in terms of three isoenzyme [Endopeptidase-1, Aminopeptidase-1 and Aminopeptidase-2] systems, by isoelectric focusing gel electrophoresis. For overall loci, the mean number of alleles and effective alleles were observed as 2.00 and 1.37, respectively. The mean value of gene diversity and average gene diversity, in overall loci, were detected as 0.23 and 0.07, respectively. Actual genetic differentiation and gene flow between different populations were calculated as 0.19 and 0.11, respectively. Pearson's correlation and multiple regression analyses indicated that eco-geographical variables have significant effects on isoenzyme genetic diversity. Landraces that have desirable agronomical and immunological resistance traits that makes them adaptable to climate change and different eco-geographical conditions are important genetic resources to utilise for the improvement of future crops of modern wheat varieties. There is a need to assess the genetic structure and genetic composition of important agronomical characters and to determine the magnitude of the genetic diversity currently conserved in the germplasm of landraces, both in farm fields and in ex situ collections and finally, strategies for the effective use of landraces, particularly of emmer wheat, should be planned and implemented in Turkey were discussed.

Restricted access

-adaptive traits derived from wheat wild relatives and landraces. J. Exp. Bot. , 58 , 177–186. Trethowan R. Drought-adaptive traits derived from wheat wild relatives and landraces

Restricted access

. Protein heterogeneity in European wheat landraces and obsolete cultivars. Genet. Resour. Crop Evol. 46 :521–528. Dotlačil L. Protein heterogeneity in European wheat landraces and

Restricted access

(white seeded). Although the two genetically different landraces ( Ceccarelli et al., 1987 ) have been grown by traditional farmers in Syria since the beginning of the 20th century, little is known about them. Indeed, these landraces may represent an

Restricted access

Niwa, K., Suzuki, H., Tominaga, T., Nasim, S., Anwar, R., Ogawa, M., Furuta, Y. 2008. Evaluation of genetic variation in high molecular weight glutenin subunits of seed storage protein using landraces of common wheat from Pakistan. Cereal Res. Commun

Restricted access

. Boggini , G. , Palumbo , M. , Calcagno , F. 1990 . Characterization and utilization of Sicilian landraces of durum wheat in breeding programmes . In: Srivastava , J.P. , Damania , A.B. (eds), Wheat Genetic Resources: Meeting Diverse

Restricted access

the initial development of winter emmer landraces of various origin in gradient growth chamber.) Növénytermelés , 52 , 599--608. Eltérő származasú őszi tönke (Triticum turgidum ssp. dicoccon (Schrank) Thell.) tájfajták

Restricted access