Flowering time and the identification of floral marker genes in Solanum tuberosum ssp. andigena

• Published in: Journal of experimental botany Vol. 71; no. 3; pp. 986 - 996
• Main Authors: Seibert, Tanja, Abel, Christin, Wahl, Vanessa
• Format: Journal Article
• Language: English
• Published: UK Oxford University Press 23-01-2020
• Subjects: Flowers - growth & development; Genes, Plant; Meristem - ultrastructure; Photoperiod; Research Papers; Solanum tuberosum - genetics; Solanum tuberosum - growth & development; Solanum tuberosum - ultrastructure; ssp; Flowering time; marker genes; potato; StMC; StSOC1; StWOX9; Solanum tuberosum ssp. andigena; StFD; StAN; StLFY
• ISSN: 0022-0957; 1460-2431; 1460-2431
• DOI: 10.1093/jxb/erz484

Abstract
Solanaceae is a family of flowering plants that includes agricultural species such as tomato (Solanum lycopersicum), eggplant (S. melongena), pepper (Capsicum annuum), and potato (S. tuberosum). The transition from the vegetative to reproductive stage has been extensively investigated in tomato as it affects fruit yield. While potato has mainly been studied with regards to the formation of storage organs, control of flowering time is a subject of increasing interest as development of true seeds is becoming more important for future breeding strategies. Here, we describe a robust growth regime for synchronized development of S. tuberosum ssp. andigena. Using SEM to analyse the developmental stages of the shoot apical meristem (SAM) throughout the floral transition, we show that andigena is a facultative long-day plant with respect to flowering. In addition, we identify the flower meristem identity gene MACROCALYX (StMC) as a marker to distinguish between the vegetative and reproductive stages. We show that the expression of WUSCHEL HOMEOBOX 9 (StWOX9) and ANANTHA (StAN) are specific to the inflorescence meristem and flower meristems in the cyme, respectively. The expression patterns of homologs of Arabidopsis flowering-time regulators were studied, and indicated that SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (StSOC1) and StFD might regulate flowering similar to other plant species.
MACROCALYX, WUSCHEL HOMEOBOX9, ANANTHA, SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1, and FD are expressed in distinct domains in the shoot apex in Solanum tuberosum ssp. andigena and provide good markers to distinguish developmental stages and organs.