Tanyolac, B. | bioRxiv Science

bioRxiv2020

Genome-wide association links candidate genes to fruit firmness, fruit flesh color, flowering time, and soluble solid content in apricot (Prunus armeniaca)

Apricots originated from China, Central Asia and the Near East and arrived in Anatolia, and particularly in their second homeland of Malatya province in Turkey. Apricots are outstanding summer fruits, with their beautiful attractive colour, delicious sweet taste, aroma and high vitamin and mineral content. In the current study, a total of 259 apricot genotypes from different geographical origins in Turkey were used. Significant variations were detected in fruit firmness (FF), fruit flesh color (FFC), flowering time (FT), and soluble solid content (SSC). A total of 11,532 SNPs based on DArT were developed and used in the analyses of population structure and association mapping (AM). According to the STRUCTURE (v.2.2) analysis, the apricot genotypes were divided into three groups. The mixed linear model with Q and K matrixes were used to detect the associations between the SNPs and four traits. A total of 131 SNPs were associated with FF, FFC, and SSC. The results demonstrated that AM had high potential of revealing the markers associated with economically important traits in apricot.

genomics↗

bioRxiv2018

VIT1-dependent Fe distribution in seeds is conserved in dicots

One third of the people suffer from iron (Fe) Fe deficiency. An underlying factor for this malnutrition is insufficient Fe intake from the diet. A major part of the human diet includes seeds of staple crops, which contain Fe that is poorly bioavailable. One reason for the low bioavailability is these seeds store Fe in cellular compartments that also contain antinutrients, such as phytate. Thus, several studies focused on decreasing phytate concentrations. As an alternative approach to increase bioavailable Fe, Fe reserves might be directed to cellular compartments such as plastids that are free of phytate. Previous studies indicated that Fe reserves can be relocalized inside the seed to the desired compartment by genetic modification, provided that a suitable iron transporter protein is used. However, to the best of our knowledge, a Fe transporter localizing to plastids have not been identified in seeds to date. To discover novel Fe transporters, we screened Fe patterns in seeds of distinct plant lineages, hypothesizing Fe hyperaccumulating sites would indicate Fe transporter presence. To this end, metal localizations in seeds of more than twenty species were investigated using histochemical or X-ray based techniques. Results showed that in Rosids, the largest clade of eudicots, Fe reserves were primarily confined in the embryo part of the seeds. Furthermore, inside the embryos, Fe was enriched in the endodermal cell layer, a well-known feature that is mediated by vacuolar Fe transporter, VIT1 in model plant Arabidopsis thaliana. This enrichment was well conserved in and beyond Rosid species. Finally, a few seeds showed novel Fe patterns, including Carica papaya which concentrated large Fe reserves exclusively in plastids called amyloplasts. Generally, Fe stored in amyloplast is considered bioavailable. Taken together, this study suggests dicot seeds store Fe mainly in the embryo, with a VIT1-dependent enrichment in its endodermal cell layer and indicate Carica papaya possess a strong Fe transporter at the plastid membrane. Once it is identified that might be useful in biofortification, as a novel tool to shift Fe to compartments where it is more bioavailable.

plant biology↗