Seedless watermelons are triploid hybrids (3n) that have been growing in popularity since the 1990s. However, the high production cost and low germination rate of the hybrid seeds pose a major problem in their production. The synseed technology could make a promising alternative for seedless watermelon propagation; however, this alternative has not yet been explored. This study aimed at producing synseeds of seedless watermelon ‘Quality’ using shoot tips as the propagules after which their germination and conversion were evaluated under in vitro and ex vitro conditions. In vitro shoot multiplication with different concentrations of 6-benzylaminopurine (BAP), synseed production from BAP-multiplied shoot tips, synseed sowing in vitro using several substrates and medium supplements, and synseed sowing ex vitro using different antimicrobial agents were investigated. Results indicated that 1.0 mg L⁻¹ BAP resulted in the highest number of shoots per shoot tip explant. Synseeds produced from BAP-multiplied shoot tips achieved faster germination compared to synseeds from non-BAP-derived shoot tips, but there was no difference in terms of conversion and acclimatization survival rates. Agar showed greater conversion and acclimatization survival rates as well as root number, root length, and shoot length than the other substrates especially when indole-3-butyric acid (IBA) at 1.0 mg L⁻¹ was added to the medium. However, this study demonstrated the possibility of using vermiculite as an alternative substrate to agar. PPM at 0.5% was a better microbial agent than 100.0 mg L⁻¹ mancozeb for ex vitro synseed sowing as it achieved zero contamination and maintained the growing potential of synseeds with 65% germination, 85% survival, and 25% rooting rates.

无籽西瓜是三倍体杂交品种 (3n)，自 20 世纪 90 年代以来越来越受欢迎。然而，杂交种子的生产成本高、发芽率低是其生产中的主要问题。合成种子技术可以成为无籽西瓜繁殖的有前景的替代方案；然而，尚未探索这种替代方案。本研究旨在使用茎尖作为繁殖体生产无籽西瓜“品质”的同种种子，然后在体外和离体条件下评估其发芽和转化。研究了使用不同浓度的 6-苄氨基嘌呤 (BAP) 进行的体外芽繁殖、从BAP 倍增的芽尖生产同种种子、使用多种基质和培养基补充剂进行的同种种子体外播种以及使用不同抗菌剂进行的同种种子体外播种。结果表明，1.0 mg L ^-1 BAP 导致每个茎尖外植体的芽数量最高。与非 BAP 衍生的茎尖产生的合成种子相比，由 BAP 倍增的茎尖产生的合成种子具有更快的发芽速度，但在转化和适应存活率方面没有差异。与其他底物相比，琼脂显示出更高的转化率和适应存活率以及根数、根长和芽长，特别是当向培养基中添加1.0 mg L ^-1吲哚-3-丁酸（IBA）时。然而，这项研究证明了使用蛭石作为琼脂替代基质的可能性。对于离体同种种子播种来说，0.5%的PPM是比100.0 mg L ^-1代森锰锌更好的微生物剂，因为它实现了零污染并保持了同种种子的生长潜力，发芽率为65%，成活率为85%，生根率为25%。