Correlation Analysis of Corm Size with Carbohydrate, Hormone, and Flowering Traits of Crocus sativus in Two-Stage Cultivation

Saffron (Crocus sativus L.) is an important medicinal crop with high economic value in the world. Due to its growth patterns and environmental requirements, Chinese enterprises employ two-stage cultivation for saffron. However, the relationship between corm size and flowering characteristics in this cultivation remains understudied. This study investigated the correlation between corm size and flowering characteristics, including flower count, stigma yield, and mass concentration percentage of crocin and picrocrocin, as well as physiological differences in corm of different sizes indoors. Results indicated that there was a significantly positive correlation with corm size and flower number (r = 0.98) and stigma yield (r = 0.98). Additionally, a positive correlation was observed between corm size and mass concentration percentage of crocin (r = 0.54), whereas no correlation existed between corm size and mass concentration percentage of picrocrocin (r = 0.19). Significant variations in soluble protein, soluble sugar, starch, and hormone (ZR, IAA, GA3, ABA) contents were noted in this study. Larger corm sizes had higher contents of soluble protein, soluble sugar, and starch. Meanwhile, starch content mostly had a decreasing trend indoors, which provides sufficient energy and nutrients for flower bud differentiation. ZR and IAA showed greater responsiveness, and increased levels of ZR and IAA potentially promote flower bud differentiation. This study provides theoretical guidance for field management optimization, yield improvement, and quality control of saffron in Chinese two-stage cultivation.