The genetic architecture of leaf stable carbon isotope composition in Zea mays and the effect of transpiration efficiency on leaf elemental accumulation. Issue 9 (14th July 2021)

• Record Type: Journal Article
• Authors: Sorgini, Crystal A; Roberts, Lucas M; Sullivan, Madsen; Cousins, Asaph B; Baxter, Ivan; Studer, Anthony J
• Editors: Huang, E
• Is Part Of: G3. Volume 11:Issue 9(2021)
• Publication Date: 2021-07-14
• Subjects: Zea mays -- carbon isotopes -- transpiration efficiency -- specific leaf area -- ionomics; Genetics -- Research -- Periodicals; Genomics -- Periodicals; Genetics; Genomics; Genes; Genetics -- Research; Genomics; Electronic journals; Periodical; Periodicals; Fulltext; Internet Resources; Periodicals; 572.8
• DOI: 10.1093/g3journal/jkab222
• Languages: English
• ISSNs: 2160-1836

Abstract

Abstract: With increased demand on freshwater resources for agriculture, it is imperative that more water-use efficient crops are developed. Leaf stable carbon isotope composition, δ 13 C, is a proxy for transpiration efficiency and a possible tool for breeders, but the underlying mechanisms effecting δ 13 C in C4 plants are not known. It has been suggested that differences in specific leaf area (SLA), which potentially reflects variation in internal CO2 diffusion, can impact leaf δ 13 C. Furthermore, although it is known that water movement is important for elemental uptake, it is not clear how manipulation of transpiration for increased water-use efficiency may impact nutrient accumulation. Here, we characterize the genetic architecture of leaf δ 13 C and test its relationship to SLA and the ionome in five populations of maize. Five significant QTL for leaf δ 13 C were identified, including novel QTL as well as some that were identified previously in maize kernels. One of the QTL regions contains an Erecta-like gene, the ortholog of which has been shown to regulate transpiration efficiency and leaf δ 13 C in Arabidopsis . QTL for δ 13 C were located in the same general chromosome region, but slightly shifted, when comparing data from two different years. Our data does not support a relationship between δ 13 C and SLA, and of the 19 elements analyzed, only a weak correlation between molybdenum and δ 13 C was detected. Together these data add to the genetic understanding of leaf δ 13 C in maize and suggest that improvements to plant water use may be possible without significantly influencing elemental homeostasis.