Investigation of Diversity of Different Agronomic and Morphological Traits in Wild Wheat Relatives

Wild relatives of wheat are one of the most important genetic resources for use in wheat breeding programs. Therefore, identifying wheat wild relatives and Awareness of the diversity in them, also protecting these species is undeniably effective in expanding the richness of the gene pool and the genetic base of new cultivars and can be a good tool for future breeders.

The present study was conducted to evaluate the genetic diversity and to investigate the relationships between traits in 49 species of wild wheat relatives in augmented design in five blocks in the Genetic Research and National Plant Gene Bank of Iran of Seed and Plant Breeding Research Institute in 2019-2020 crop year.

Based on the results of analysis of variance, there was a significant difference in the probability level of 0.01 between different wild relatives of wheat in terms of height, peduncle extrusion length, peduncle length and grain length and grain width. The values ​​of diversity coefficients also indicated high diversity between different species of wild relatives in terms of morphological traits other than flag leaf length. The highest coefficient of genetic variation and the highest heritability was related to peduncle length trait. Based on the results of estimating the correlation coefficients between traits, there was a positive and significant relationship between yield and yield components. Based on the results of regression analysis, five traits of spike weight, harvest index, height, grain length and number of grains per spike were determined as traits affecting grain yield. Among these traits, spike weight was mainly direct and number of grains per spike was indirectly, affected grain yield. The results of factor analysis led to the identification of three factors that explained 84.39% of the differences between the data. The dendrogram obtained from the cluster analysis divided cultivars and species into three general groups based on all traits. The genotypes in the fourth and fifth groups can be used for breeding and production of new cultivars by improving biological yield and grain yield, due to positive deviation from the total mean for height, flag leaf length and grain length traits, and the first group genotypes can be used to harvest index improvement. 

There was a significant variation in morphological traits among the studied wheat wild relatives, which can be used for breeding programs of genetic resource.