Identification of haploids and diploids in maize using seedling traits and flow cytometry

• Published in: Crop breeding and applied biotechnology Vol. 21; no. 4
• Main Authors: Baleroni, Alessandra Guedes, Pelozo, Andressa, Kamphorst, Samuel Henrique, Carneiro, José Walter Pedroza, Rossi, Robson Marcelo, Scapim, Carlos Alberto
• Format: Journal Article
• Language: English; Portuguese
• Published: Vicosa Crop Breeding and Applied Biotechnology 2021
• Subjects: AGRONOMY; BIOTECHNOLOGY & APPLIED MICROBIOLOGY; Coleoptile; Corn; Diploids; Flow cytometry; Germination; Growth chambers; Haploidy; Methodology; Nondestructive testing; Phenotypes; Seedlings; Seeds; R1-Navajo; haploid inducer; Doubled haploid
• ISSN: 1518-7853; 1984-7033; 1984-7033
• DOI: 10.1590/1984-70332021v21n4a54

The seedling traits is a simple and non-destructive methodology used to identify haploids/diploids in maize. This study aimed at establishing an optimal germination temperature to evaluate this methodology and verify its effectiveness. Haploid and diploid seeds, obtained from crosses with the haploidy inducer TAIL9, were classified using the R1-Navajo marker and placed to germinated in growth chambers maintained at different temperatures. After 96 h, radicle and coleoptile lengths and the number of lateral seminal roots were determined. Cut-off points for these traits were established using Receiver Operating Characteristic curves and a new haploid/diploid classification was performed and compared to the plant phenotype (gold standard) to obtain false discovery rates and false negative rates. The seedling traits methodology successfully differentiated haploids and diploids, proving to be effective in eliminating false positives, selected by the R1-Navajo marker. The temperature of 30 °C was established as the optimal germination temperature for this study.