Analysis of agronomic and molecular properties to determine the suitability of bread wheat (Triticum aestivum L.) genotypes for organic agriculture

The goal of this study was to examine the suitability of numerous bread wheat genotypes for organic farming under rainfed settings in terms of morphological, physiological, yield and quality features, as well as their potential to be parents in organic breeding. Furthermore, the genotypes chosen for these goals were analiyzed molecularly level, and gene expression levels relevant to nitrogen use efficiency were assessed. The study was carried out in Dicle University Faculty of Agriculture, Field Crops Research and Experiment Station for two years in the 2019-2020 and 2020-2021 growing seasons. In the first year of the study, a total of 157 bread wheat genotypes, consisting of 68 local varieties collected from some provinces of the Southeastern and Eastern Anatolia Regions, 63 commercial varieties, and 26 advanced lines developed in the Department of Field Crops of the Faculty of Agriculture of Dicle University, were used as material. In the second year of the trial, 30 genotypes chosen based on the first year's results were tested using a randomized complete block design. At the end of the second year of the study, 12 genotypes were determined with good and bad performance under organic farming conditions. In these genotypes, qRT-PCR analysis was performed to evaluate the efficiency of genes related to nitrogen utilization efficiency, which is of great importance in adapting to organic conditions It was determined that the investigated properties were generally lower in organic conditions compared to conventional conditions, whereas low scores were obtained in parameters that cause yield loss such as disease and lodging.. In the second year of the study, the values obtained in organic farming conditions were adversely affected due to the limited nitrogen fertilization and the lack of precipitation. According to the results of qRT-PCR analysis, it was determined that the TANRT2.1 gene, which is one of the nitrate transporter gene family, has the highest expression level in bread wheat genotypes and Alada genotype has been found to be particularly efficient in nitrogen use efficiency in organic conditions. It was also discovered that the Alada, Asure, Karacadag-98, and 6DZT-03-01 genotypes were the most suitable for organic farming by the end of the second year of the research. In the selection of high yielding genotypes for adaptation to organic farming, it was discovered that earliness, a high NDVI value, spikelet numbers, grain number, and grain weight per spike were all important characteristics to consider.