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
The growing interest in emmer cultivation has no doubt been stimulated by the increasing demand for traditional foods with an image of naturalness, especially on the organic market. The new economic situation could stimulate the breeding and production of emmer as the source of an especially valuable foodstuff. It is the task of breeders to produce emmer varieties that can survive even the hardest winter occurring in the targeted cultivation area without serious damage. The best sources to improve the winter hardiness are probably the emmer genetic resources stored in genebanks. Unfortunately no public data are available on the frost tolerance and winter hardiness of the various genebank accessions. In the present research the frost tolerance and winter hardiness of 10 winter emmer genebank accessions were studied under nursery and phytotronic conditions. The results suggest that the majority of the populations studied are frost-sensitive, and only few landraces have an acceptable level of winter hardiness and frost resistance.
Authors:F. Braadbaart, J. van der Horst, J. Boon, and P. van Bergen
Whole grains of emmer wheat were heated in a pre-heated tube oven at temperatures ranging from 130-700C under controlled
anoxic conditions for maximum 280 min. For each temperature a separate experiment was carried out. Physical properties including
mass loss, thermal lag, external and internal morphology and the vitrinite reflectance, C and N content, and DTMS under CI
(NH3) and EI conditions were used to monitor changes as a function of the temperature. The results show remaining starch and protein
rich material up to 250C. From 310-400C a secondary, thermally stable, product is formed and at higher temperatures a strongly
carbon enriched tertiary product.
Authors:Ö. Özbek, B. Göçmen Taşkin, S. Keskin Şan, V. Eser, and O. Arslan
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.
The multiplication and characterisation of genetic stocks originating under very different ecological conditions is a problem constantly encountered in gene bank research. However, the major components of the original environment, such as temperature, light and humidity, can be reproduced under artificial conditions in the phytotron. The gradient, or inhomogeneous, chamber available in the phytotron of the Agricultural Research Institute of the Hungarian Academy of Sciences, Martonvásár, makes it possible to elaborate plant growth programmes optimised for the various developmental phases of each population in a single step. In this chamber gradients of two extremely important environmental factors, temperature and illumination, can be simultaneously programmed, thus allowing the optimum light × heat combinations to be identified. However, the use of complete inhomogeneity (light × heat) makes it extremely difficult to evaluate the experimental results, since biometric methods based on traditional statistics are unable to handle this situation. It is thus essential to find a method suitable for the comparative analysis of continual variables (Okada et al., 2000). The present paper reports on the first phase in the development of a plant growth programme for emmer, based on investigations made on two gene bank accessions of winter Triticum turgidum ssp. dicoccon (Schrank) Thell. (MvGB 301 and MvGB 304). In the gradient chamber study the accumulation of dry biomass in three-week-old plants was investigated as a function of temperature and light intensity. The results suggest that a temperature of 10-12°C combined with low or moderate light intensity is optimum for the germination and initial development (0-4 weeks) of emmer. These conditions also induced good tillering, which is extremely important, especially for gene bank accessions where the possibility of seed multiplication and field cultivation is limited.