Work

Effect of hormone concentration on callus induction and plant regeneration induced from daylily (Hemerocallis fulva) anther

Year: 2025

Type: article

Abstract: In modern plant breeding, anther culture is an important biotechnological tool that shortens the breeding cycle and improves efficiency, thereby playing a crucial role in genetic improvement and cultivar development. To date, there have been few studies on anther culture in daylily ( Hemerocallis spp.). The present study aimed to investigate the effects of the microspore developmental stage, low-temperature pretreatment duration, and phytohormone combinations on callus induction and plant regeneration from daylily anthers. We first studied the morphological characteristics of flower buds and anthers at different microspore developmental stages, and then used anthers from different developmental stages for callus induction. The results showed that microspores at the late uninucleate stage were optimal for callus induction. Low-temperature pretreatment at 4°C for 24 h could effectively promote the formation of callus tissue in daylily anthers. In the (L9(3 4 )) orthogonal array experiment, the callus induction rate was highest (45.57%) in the medium containing MS (Murashige and Skoog) + 70 g/L sucrose + 2 mg/L Kn (Kinetin) + 2 mg/L 2,4-D (2,4-dichlorophenoxyacetic acid) + 0.1 mg/L NAA (1-naphthaleneacetic acid). Among the nine media for callus bud differentiation, the highest adventitious bud induction rate was achieved with MS + 30 g/L sucrose + 2 mg/L 6-BA (N6-benzyladenine) + 0.1 mg/L NAA (43.33%). The optimal rooting medium was MS + 30 g/L sucrose + 0.05 mg/L NAA + 0.1 mg/L IBA (Indole- 3-butyric acid) (93.33%). Flow cytometry and Simple sequence repeats (SSR) analysis showed that all 55 intact plantlets derived from anthers were diploid. This study optimized the anther culture technique for daylily and proposed a comprehensive anther culture method for callus induction and plant regeneration. For the first time, plant regeneration was achieved via anther culture in daylily, providing relevant theoretical and technical support for genetic research and daylily breeding.

Source: Plant Methods

DOI: 10.1186/s13007-025-01469-3