Δ¹²-fatty acid dehydrogenase (FAD2) is the essential enzyme responsible for catalyzing the formation of linoleic acid from oleic acid. CRISPR/Cas9 gene editing technology has been an essential tool for molecular breeding in soybeans. To evaluate the most suitable type of gene editing in soybean fatty acid synthesis metabolism, this study selected five crucial enzyme genes of the soybean FAD2 gene family—GmFAD2-1A, GmFAD2-1B, GmFAD2-2A, GmFAD2-2B, and GmFAD2-2C—and created a CRISPR/Cas9-mediated single gene editing vector system. The results of Sanger sequencing showed that 72 transformed plants positive for T₁ generation were obtained using Agrobacterium-mediated transformation, of which 43 were correctly edited plants, with the highest editing efficiency of 88% for GmFAD2-2A. The phenotypic analysis revealed that the oleic acid content of the progeny of GmFAD2-1A gene-edited plants had a higher increase of 91.49% when compared to the control JN18, and the rest of the gene-edited plants in order were GmFAD2-2A, GmFAD2-1B, GmFAD2-2C, and GmFAD2-2B. The analysis of gene editing type has indicated that base deletions greater than 2bp were the predominant editing type in all editing events. This study provides ideas for the optimization of CRISPR/Cas9 gene editing technology and the development of new tools for precise base editing in the future.

Background: As a coarse grain variety, azuki beans and mung beans were widely grow in Asia. Due to the lack of management in the long-term cultivation process, leading to the mixed phenomenon among azuki bean and mung bean varieties, which seriously affects the cultivation and breeding of azuki beans and mung beans. The current study aims to construct the genetic map using SSR markers for the genetic classification of beans. Methods: In 2019, 46 test materials were raised to extract the young leaves. The DNA fingerprinting of 46 cultivated azuki bean and mung bean resources were constructed using 38 pairs of SSR primers and their genetic diversity were analyzed. Azuki bean and mung bean varieties are divided by hierarchical clustering analysis. Result: Totally 18 primers have shown polymorphism among the 38 primers and 188 polymorphic bands were amplified with average PIC of value 0.8302. According to the K mean cluster analysis method, 23 azuki beans and 23 mung beans resources were grouped into three categories. According to the hierarchical cluster analysis method, azuki beans were divided into four categories and mung beans were divided into six categories. The 46 azuki bean germplasm resources could be distinguished by screening nine pairs of digital fingerprint constructed by core primers.

Background: Soybean is an important oil and cash crop, soybean protein is the main source of protein for human consumption. Soybean oil is also major edible oil that is rich in unsaturated fatty acids and is more conducive to human long-term consumption than animal oil. An important research direction of current soybean breeding is improvement of the protein and fat content using marker assisted selection and many reports of associated quantitative trait locus (QTL) mapping have been documented. Until to now, a total of 241 QTLs associated with protein content and 315 related to fat content have been collected on the SoyBase website. Methods: In this study, 236 F2 generation plants and a derivative group were constructed by using Jiyu50 and Jinong18, obtained from Jilin Province. Combining three years of phenotypic and molecular detection data, using the ICIM method, one-dimensional scanning detected 24 QTLs related to protein and fat content, two-dimensional ICIM analysis of F2:3 families detected 7 pairs of epistatic QTLs associated with fat content. Result: Based on a mixed model for major genes and polygenes, the C model was determined the optimal genetic model for protein and fat content, with genetic rates of multiple genes of 71.15% and 79.15%, respectively. In the detection of high-oil molecular markers, the detection coincidence degree was Sat_238 greater than Satt 100 greater than Satt 150 greater than Satt 636 greater than Sat_287 = Sat_342, while this was Satt150 = Sat_342 greater than Satt100 greater than Satt 636 greater than Sat_287 greater than Sat_238 for high-protein markers. The QTL localization results showed that 9 microeffect QTLs related to protein content and 7 microeffect QTLs related to fat content were detected. Isolation analysis results were generally similar to those of QTL mapping. One stable QTL associated with protein content and two stable QTLs associated with fat content were identified as being of some application value in soybean molecular marker-assisted breeding.