| Wild emmer wheat(Triticum dicoccoides, 2n=4x=28, AABB) is the wild tetraploid ancestor of A and B genome of the common wheat(Triticum aestivum, 2n=6x=42,AABBDD), which have many good traits compared to other relatives. Wild emmer wheat is the secondary gene pool of hexaploid common wheat which can be used to improve common wheat. Israel is one of the origin and diversity centrey of wild emmer wheat. Evolution Canyon is a local microcosmic natural laboratory and an optimal natural micro-scale model for unraveling evolution and diversity in different environments. There is the wild emmer wheat widely distributing. A total of 38 accessions of wild emmer were gathered from two stations(Stations 2 and 7) at the “Evolution Canyon” 1(EC 1) in Mount Carmel. Disease resistance, quality parameters, storage protein and SSR markers had been investigated to evaluate the genetic diversity between the wild emmer wheat from the inter-slope.Mechanism of the micro-environment influence on the evaluation of wild emmer wheat had been discussed in this study. The main results are as follows:1. Analysis of genetic diversity of four major agronomic characters(in the aspect of height, spike length, 1000 kernel weight and kernel number) for all tested materials have been done in our research. The average value of plant height on ES and AS were around86.903 cm and 108.926 cm, respectively. Spike length was varied from 6.067 to 9.300 cm and the mean was 8.120 on ES. The variance of the spike length on AS is 7.767 to 10.167 cm and the mean was 8.860. Kernel number was varied from 16.333 to 32.000 and the mean is 25.376 on ES. The variance of the kernel number on AS is 20.667 to 39.000 and the mean was28.815; The variance of 1000 kernel weight on ES and AS were 16.150-30.950 g and 15.350-26.675 g, respectively, and the mean is 24.698 g and 20.918 g, respectively. The mean of genetic diversity index of four characteristics on ES and AS were 2.180 and 0.398 in plant height, 0.305 and 0.372 in spike length, 0.330 and 0.335 in kernel number, 0.361 and 0.381 in1000 kernel weight, respectively.2. In order to fully exploit the wild emmer wheat germplasm resources in genome, the genetic diversity was investigated with 278 SSR markers in 38 accessions. Overall, 148 pairs of SSR primers(53.23%) amplified polymorphic products between the AS and ES. Thefrequency polymorphism of SSR markers between AS and ES were similar on the genomes A and B, which are around 50% and 56.5%. Cluster analysis showed that the 38 tested materials were divided into 3 groups, i.e. the first group including 18 accessions on AS, the second group composing 17 accessions on ES except ES5, ES13, ES14, and ES5, ES13, ES14 were clustered into the third group individually.3. The quality characteristics in 38 accessions were determined by near infrared spectroscopy technology. The protein content, absorption, wgluten and development time showed significance(p<0.01) between AS and ES and they were significantly different(p<0.05) in stability time. Based the above quality characteristics, 38 materials all belong to strong gluten wheat(stability time ≥10min, wgluten ≥ 35%, protein content ≥15%).4. The SDS-PAGE analyse results showed that they have diversity on HMW-GS in the wild emmer wheat on inter-slope. We found 3 alleles on Glu-1 loci, i.e. 1 allele on Glu-A1 which was found on AS, 2 alleles on Glu-B1 which were both found on AS and ES.5. The reaction of the 38 accessions to Bgt E09 is different between AS and ES. All of18 AS genotypes were susceptible to powdery mildew isolates of Bgt E09, while another 20 ES genotypes were highly resistant to Bgt E09 at the seedling stage under the same controlled biological incubator conditions.6. 38 accessions of wild emmer were tested for powdery mildew resistance at seedling stage using 3 physiological races of Blumeria graminis. The results showed that 20 accessions from ES were resistance to more than 2 physiological races and exhibited diversity on reaction to Bgt E21. 5 accessions from AS tested were all susceptible to all of the physiological races of Blumeria graminis.7. Distant hybridization and backcross between common wheat and wild emmer wheat will be made to broaden the genetic background of common wheat in the future study. |
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