Mohammad Reza Mirzaei,
Volume 11, Issue 2 ((Autumn & Winter) 2025)
Abstract
Extended abstract
Introduction: One of the most critical factors in achieving optimal sugar beet root performance at harvest time is appropriate plant density, which depends on high seedling emergence rates and subsequent seedling growth facilitated by using seeds with desirable vigor. Various seedling traits are key determinants of seed vigor and quality in sugar beet.
Materials and Methods: To evaluate germination vigor and seedling growth under laboratory conditions, traits such as maximum germination, hypocotyl length, radicle length, and fresh and dry seedling weights were measured in ten single-cross hybrids derived from crosses between ten male-sterile maternal lines and one paternal line, produced in three different seed production environments. Additionally, correlations between these traits and seedling emergence traits in greenhouse conditions, as well as seed chemical properties, were examined.
Results: The results indicated that seedling traits, which reflect seed vigor, are primarily influenced by two factors: the sugar beet seed production environment and genetics. Analysis of correlation coefficients between laboratory seedling traits and greenhouse seedling emergence traits, as well as seed electrical conductivity, revealed that genotypes with low electrical conductivity and low total soluble solids in the seed pericarp germinated faster and emerged more quickly under greenhouse conditions. Thus, high electrical conductivity in the sugar beet seed pericarp was associated with low seed vigor. Furthermore, significant correlations were observed between seedling emergence speed and mean emergence time in the greenhouse and hypocotyl length in the laboratory, showing positive (+0.91**) and negative (−0.82**) relationships, respectively. Therefore, genotypes with longer hypocotyls in the laboratory exhibited faster seedling emergence in the greenhouse. Consequently, single-cross hybrids such as MS KWS × OT 231, which had greater radicle length (8.49 cm), seedling length (14.66 cm), and radicle-to-hypocotyl ratio (1.37) under laboratory conditions, also showed a significant increase in mean dry shoot weight (1.89 mg) and seedling vigor weight index (8.26) in the greenhouse compared to other single-cross hybrid.
Conclusions: Therefore, it appears that seedling traits and chemical characteristics of sugar beet seeds can be used to predict seedling emergence performance in the greenhouse and potentially in the field. However, for validation and precise assessment, it is recommended that this experiment be conducted under field conditions.
Highlights:
- Differences were observed among genotypes in terms of seed characteristics and the maternal environment in which the seeds were produced.
- Poor sugar beet seed vigor can reduce both the potential emergence percentage and the speed and uniformity of seedling emergence compared to high-vigor seeds.
- Seedling traits in sugar beet are indicators of seed vigor and are influenced by both the seed production environment and genetics.